Elements are the most basic building blocks. They have been organized in 4 main categories. We placed the most frequently used elements, Text and then Images at the top of the pane. Further down there’s a collection of ‘common’ elements (we could not agree on better wording indeed…) to add, for example,  videos or custom HTML snippets.

Elements like buttons and social media icons are grouped as Interaction elements. The last category consists of elements that can help to create sophisticated responsive Layout constructs. Each of these categories is addressed in a bit more detail below.

The placeholder texts can be replaced by typing or pasting text blocks in Text Edit mode. Tripple clicking a text element will start the text editor. Alternatively you can use the edit button on the Design pane or use the right-click menu.

The Text Editor can also be used to add inline links and formatting. The link below provides more information.

Additional resources

• Working with the Text Editor

Using an online image.

You will notice that a newly added image will not be wider than 200px. This can be changed on the Design pane with the max-width control.

Bootstrap Builder uses the brandnew <picture> element. This allows you to change the image at breakpoints, serving smaller images to mobile devices for better performance. Our very own Suzanne wrote an excellent article about this, please check it out!

Additional resources

• Working with the < PICTURE > element
  
• Tip: Working with pictures in the CoffeeCup responsive apps.

Well, maybe not all that common… The horizontal rule certainly is, but we need to talk a bit more about the HTML en Video elements.

The HTML Element can be used to add custom code snippets or exports from other apps. This can be CoffeeCup apps like Web Form Builder, Responsive Content Slider or 3rd party apps. To not interfer with the other elements on the page currently a placeholder visual is displayed. We expect to update this in a next version of BB in the near future.

The Video Element allows for embedding responsive videos in the page. Indeed, responsive because most other video embeds are not automatically adjust to different screen widths!

Currently you can embed videos from the most important video services. If there’s one you think we should add please use the ‘Rate this app’ function under help and let us know in the comments what we can do for you.

Additional resources

• Working with the HTML Element.
  
• Adding a custom build slide show.

The elements in the group generally perform and action following interaction with the visitor or user. A Button Link can open a menu, reveal a hidden element or show modal dialog. It can also take the user to a different location, on the page, site or to an entirely different site. Component (see below) often include this interactive behavior.

The Form Container, together with the Submit Button can, for example, be used to build custom HTML Paypal payment buttons. It can also can include other form elements found under the Input dropdown. Please note that the form (elements) can be hooked up — inputs for this are provided on the Design pane. However, form scripts or creating a fully functional form are beyond the scope of this app. For that we refer to Web Form Builder (with exciting news there coming soon…).

The Social Icons can both be used to build a following on the social networks and allow vistors to share information. Select the Follow or Share option on the Design pane (for networks that support these), then fill out the various options.

Additional resources

• Creating a custom Paypal payment button.
  

Layout elements offer more granular control over the page layout. They are also be used to build logical groups of elements or groups with a specific role of function such as a footer or card component.

The Subgrid Element gives the exact same control as the overall Bootstrap grid, but within a subset of the page. This element can be added to a column (or even container) to create custom layouts within that section. Just as the main grid subgrids can be reconfigured, e.g. columns widths can change, at breakpoint. These changes are also managed on the Layout pane.

List Containers are unordered lists with each list item being it’s own container. They are often used to build navigation components.

Containers often serve as ‘wrappers’ for related elements. When creating a card (component) the container often encapsulates one of more text elements, an image, a button and sometimes sub-container with additional elements. We will look at this in more detail in the Component section.

A link Container functions exactly as a container, but wrapped in an <a> tag, making it one big link element.

Additional resources

• Layout control with subgrids and containers.

In addition, components can come in varying levels of design. Most components are minimally styled so that they can be adjusted to the tone of a theme with minimal effort — without needing to reset or redo too many predefined properties.

However, certain components have more styles applied in order to make more complex designs readily available. The focus will still mainly be on the function, not on the design, like the card overlay below.

Vintage CoffeeCup Shirts

Very limited availability. Tweet about Bootstrap Builder and you might get one free!

Tweet now

Tweet now

In Preview mode (click icon on toolbar) the card will be covered by another container upon hover. The role of the component is to make this overlay functionality readily available — the exact content and style of both containers should be adjusted to fit the specific message and appearance of the page or site it is used in.

The components included in the project can be accessed on the Components sub-pane of the Content pane.

The first part of the pane shows a preview of the component. To improve visibility — a white component does not display that well on a white background — the background color of the previewer can be toggled. The bottom left button can change the setting between white, black and transparant.

The plus and minus buttons next to the background color button can be used to zoom in and out. In case there are similar components in the project, this provides a good level of detail to find the right one.

The preview shows the currently selected component form the list below the preview window. Clicking on a component will expand it so the name can be edited. To add a component to the canvas, click the plus (+) button. It will get inserted below the currently seleted element. If a columns or container is selected, it will be placed below the last element in the parent. If the component itself is a column or row, it will be placed below the currently selected container or row.

The New Component button creates a fresh component based upon the currently selected element (group). This component will be placed at the bottom of the list. Project components can not be reordered, filtered or sorted at this moment.

To remove a component from the list use the delete (X) button. Note this this will not remove the component from the canvas, only from the list.

Currently components reside in projects. The "Blank with Components" theme comes with a handy collection of prebuilt components that can be used as building blocks for new projects.

Most of the components found in the theme are core framework components — they are very similar to the components in the official Bootstrap documentation. Using these ‘base’ components this theme can be used for both for quick functional prototyping and as a solid, proven, foundation for new projects.

In addition we are creating a project that includes all common Bootstrap components. Right, there’s a lot of them so it is a work in progress. But we did not stop there, it includes descriptions of how these components have been constructed as well as improvements and variations.

Bootstrap components generally consist of a number of nested elements combined with predefined classes. The image below shows the classes for the navigation bar.

The bootstrap classes for the nav bar component above.

The image shows that the original Bootstrap classes have been disabled. This makes sure that the ‘extra’ styles are only tied to the -cstm class. Removing that class will remove these additional styles with it. We will talk more about the use and de-selecting of classes in the Design pane section.

As mentioned in the alert box in section 2 overview, sometimes tweaks have been made to these framework specific components. To not change any of the stye rules of the original classes, normally a class with the extension -cstm has been added. In the image below this is the navbar-cstm class.

Disabling classes for proper style organization

Themes will also have a selection of prebuilt components. This project, for example, includes the CoffeeCup Alert component, making it easy to insert the alert when needed.

Themes will also have a selection of prebuilt components. This project, for example, includes the CoffeeCup Alert component, making it easy to insert the alert when needed.

Currently components are project specific. Being able to use prebuilt components in any project in any state of progress would be a big time saver. The same holds true for custom build components, they really could help kick-off a new project as well. So here’s what we plan to do...

The component library is envisioned as a service that will allow you to collect, organize, tweak and share components. It will be rolled out in phases and the development direction will be heavily influenced by customer feedback.

Part of the service will be free when used with a paid version of our responsive apps. There will also be a premium extension which…will be even better! We will add details on this later.

In phase 1 the service will be integrated into our responsive apps. In this phase you will be able to browse the CoffeeCup Component Collection when working on a project and include the ones you need. You will also be able to export project components to the library and select them for usage in different projects.

For the sharing of components between customers there likely will be a CoffeeCup Certified Components service.

Components can be given a description and organized in folders.

We have drafts for Phase 2 of the component library but will let the final specification be influenced by the user experience and input.

Adding a Symbol to the Canvas works the same as for components. However, any changes to a Symbol will update all of the ‘instances’ — wherever they are located in the project Bootstrap Builder will keep them all exactly the same everywhere.

Creating a New Symbol also works in the exact same way as creating a new Component. When a symbol is deleted, it will be removed from the list, but all instances will still be in the project. From that moment they will behave as normal element groups, any changes will no longer trigger updates anywhere else.

When looking at the image below, you will also note a few differences. For starters, the name of the Symbol is followed by an instances count. This tells you how many times the Symbol is used in the project.

Managing Symbols

The name of a symbol can be change using the Name input. With the See on function you either can circle through the pages where an instance of the symbol is located, or directly jump to a specific page with the dropdown. Using this function the canvas is automatically scrolled to the place on the page where the Symbol is located. 

The Bootstrap grid uses a 12 column system — basically that means that each row can hold up to 12 columns. With each column spanning ¹/₁₂ of the row, the 12 columns will fit. However, columns can also be instructed to take up — 'span' — a larger part the row. This is done with the span-width dropdown.

A span of 6 means a column takes up half (⁶/₁₂) of the row. That leaves room for another column with a span of 6 next to it (or 2 columns with span 3 etc). If the total span exceeds 12, the columns that don’t fit will be placed below the proceeding columns. This way content can be placed next to each other on wide screens, and appear stacked on mobile devices.

The span-width control is the most important tool for building the layout and for subsequently adjusting the layout for different screen widths. Layout changes at breakpoints will be addressed later in this document.

The Offset and Push/Pull controls can be used to create advanced layouts. The layout of this document provides a good example.

At small and medium widths — everything on the left of the second (768px) Bootstrap breakpoint — all columns span the full width of 12 columns. However, this changes on the right of the breakpoint — there the main columns use a span of 9 and are being offset by a span of 3 to create room for an occasional column on the left.

On the right of the third breakpoint another layout change is made. The main columns get a span of 5 and are being offset by 2.

Layout adjustments like this are super easy to create with Bootstrap Builder. How this exactly works will be explained further down below. First, let’s get to work with the great Design pane!

Additional resources

• Building a custom responsive layout in 9 steps
• Grids for bullet-proof responsive design

The length of the Element section varies per Element Type. The image shows what the section will look like when an element of Type Picture is selected. The element type here is purely informative, this can not be edited (right now).

The ability to add CSS selectors — Classes and ID — to an element  is an important part of this section. A selector ‘binds’ an element or group of elements to design rules defined in the Style section on the second half of the Design pane.

The Predefined dropdown can be used to search and add classes for which the design rules have been pre-specified in the Bootstrap framework. For example, the img-cirlce class that can be seen in the screenshot adds a large border-radius value to an image, making it appear as a circle.

Clearly this can also be done manually with the Border tool in Bootstrap Builder. There is no requirement to use these predefined classes, but sometimes they come handy, especially when creating components such as a navigation. In addition, the design rules associated with a predefined class can be fully customized using the CSS tools in the Style section.

The Picture dropdown we discussed before and is specific to this element, as is the input for the Alt text.

The buttons below the Alt input can be used to duplicate or delete the element. In case a text element is selected there will be a third button — this edit button can be used to start the text editor.

The data attributes play an important part in adding interactivity to a design. See them as ‘hooks’ that tie and element to Javascript. and clarifying can be used to as and to specify additional information about the element.

For those that have been working with selectors before, the workflow in Bootstrap Builder will feel intuitive and powerful. It will still help to give this section a quick read and, for example, familiarize yourself with the color coding system for the different selector types.

If you never heard about or worked with selectors before, no worries. Our responsive apps can also automatically create selectors. However, to get the most out of our apps — to speed up the design workflow and make it easy to maintain any projects — we do recommend to slowly start accustoming yourself with the apps selector system and predefined Bootstrap classes. This section will serve as your guide.

A selector defines — ’selects’ — the elements to which a set of CSS rules applies. This is incredibly powerful because it makes it fast and easy to give multiple elements the same appearance. Or to apply the design rules to a newly added element without having to redefine all these rules. Let’s quickly go over an example using the class selector.

In Bootstrap a button is created by adding the class btn to an element. The class (name) is the carrier of a set of styles such centered text, padding around the text and so on, that this way get applied to the element.

Other styles can be added by extending the rules set for the same class, or by adding another class with new rules. Bootstrap uses the second approach — by defining all base button styles on the btn class and applying additional rules through new classes, contextual variations are created.

In the example below all three button elements use the btn class. Then, the primary button is created through the btn-primary class, the success button uses btn-success and the information button btn-info.

The additional class names create the background color and make the text white. Now you can make changes to all buttons by working with the btn class, to all primary buttons using the btn-primary class and so.

If you prefer a different type of base button set in your project, for example buttons that are the same width and don’t have rounded corners, simply define these styles (in the style section that we will look at in a bit) on the btn class and all buttons will take on that appearance.

Please note that I had to add one more class to make these changes, if I had done that one the btn class itself it would also have affected the previous example.

With this explanation and example under our belt, we should be ready for some more selector goodness. We will do that when discussing the style section next.

As explained above, style definitions are related to selectors and the top part of the style section is used to manage exactly that.

The Apply To dropdown is used to select the type of selector the style rules will be associated with. The choices are between Element Type, Class and ID.

The State dropdown can be used to specify a special state of the element targetted by a selector. For example :hover will apply a style when the user hovers over the element associated with the selector.

The Reset function helps to keep the project code lean and clean. The dropdown gives an overview of the styles that have been applied. Styles can be removed by clicking on them. 

Each of these three functions is explained in more detail below.

The Style controls are organized in logical sub-sections such as Dimensions and Typography, on the second part of the Style section. They are discussed in part 3 below.

The selector options in the Apply To dropdown start with the broadest selection of elements, followed by a subset, and ends with the selection of a single element:

1. The Type selector is used to define styles for all elements of the same type.
2. When styles are associated with a Class selector, all elements (of the same type) that have that class will get them.
3. Each ID is unique, the style definitions will only apply to the currently seleected element.

The three selector types.

The most efficient workflow is to first define styles for element types. This way a common ‘starting style' for all elements of that type can be defined.

For example, when Type is selected in the dropdown, further down on the pane in the Typography section Roboto can be set as the default font-family for all paragraphs.

The Type selector in action.

As can be seen from the above image, styles applied to the type have a pink indicator.

This way the font-familiy and font-size for all paragraph can be updated with one single edit. Also, whenever a new paragraph is added, these styles will already be present. 

Additional resources

• Selectors for an efficient design workflow

With all default styles for the elements in place, Classes can be added to create design variations. For example, certain paragraphs that perform a different role can be given a different font family, size and/or color using a class selector.

To apply styles to a Class simply enter a class name in the Classes box (in the Element section of the Design pane). Also make sure to select Class in the Apply To dropdown. Now all style adjustments with the design controls below —yes, we will get to work with them real soon! — will be tied to that class.

Any control used for applying a style to a class uses a blue indicator, like the font color thumbnail of the image in the previous section.

So what happens when different styles are assigned to different selectos? Some selectors are more powerful than others, their styles will prevail. In CSS this is called specificity, the styles from a more specific selector will take precedence over styles from less specific selectors.

A Class selector is more specific than a style applied to a Type and will therefore prevail. On its turn, an ID is more specific than a class and will prevail. Styles applied to an ID have an orange indicator.

Styles attached to a class selector are intended to be used by multiple element. To add the class to another element simply type the class name in the Class input box. The image below shows that the auto-complete can be a great help!

Adding and deselecting classes.

An element can be targetted by up to 5 different classes. Styles can be applied to a specific class selector by deselecting other classes. Deselected classes are gray (see ’step-p' above), any style updates will not apply to them, only to the class or class combination currently selected.

Styles can also be applied to class combinations. They are more specific than a single class and therefore these styles will take precedence.

One of the criticisms on (the use of) Bootstrap is that it leads to sameness — many sites created with Bootstrap look and feel the same and lack authenticity. Too many things have been predefined in too much detail.

In comparison, a framework like Foundation 6 (used by Foundation Framer) is less ‘opinionated’. With fewer framework styles to override and having a more neutral canvas to start with, designs are more unique.

There is something to say about both approaches and depending on the situation a specific approach or framework might be better suited.

Nevertheless we feel the ‘sameness effect’ is muted by Bootstrap Builder — the visual controls make it super easy and fast to assign different styles to the Bootstrap classes and to give the elements and components a totally different appearance.

In addition, new custom classes can be added that bring their own style rules to the table — creating some unique is totally up to the designer!

As we saw in Section 1.1 with the button examples, Bootstrap has done a great job in modularizing the styles. These modular classes are designed to be used depending on the role and context of an element.

For example, this paragraph uses the class lead which makes it stand out 

Using the modular class structure can be a great help in the initial phases of the project and help to think about the role of the content element. Updating the appearance by editing the styles associated with the classes, or adding new classes with different style rules is a cinch.

In this paragraph the lead-brd class is used to make it appear different.

The Predefined dropdown facilites the use of the framework classes and prevent typos. Simply start typing what you are looking for and the list will show an increasingly precise list of matching classes.

We already saw that pink is associated with style definitions for an element type and that a blue indicator tells us the style was set on a class. An orange indicator would correspond with a style coming from an ID. This covers most of the situations, but there’s a few additional cases we need to iron out.

First of all, we learned that classes can be deselected so style can be assigned to specific individual classes or class combinations. When a style applies to such a deselected a class (or class combination), the style control has a  gray  indicator.

In the image, the class side-heading is deslected. On the Typography section the indicators for the font-size, line-height and text-align controls are gray. This means that these styles belong to the side-heading class.

Here’s one more situation where the color coding can come in really handy. When styles are applied to multiple selectors, e.g. a class and an ID, the style controls show the values of the styles associated with the selector type we are currently working with. This is the selector — Type, Class or ID — visible in the State dropdown. This sounds more complicated than it is really, a quick example will make that clear.

In the image the font-weight control shows a value of 400 - normal with an orange indicator. However, the Apply To dropdown shows we are currently working with class selectors. That means that the visible value — 400 - normal — belongs to a class. The orange indicator however tells us that a font-weight value has been specified for the ID as well. To view this value simply switch the Apply To dropdown to ID and the value associated with the ID will show up in the control.

The indicator will take the color of the strongest selector, because that is the style value that in the end will be visible in the browser. So in our case, if a different font-weight has been set for the ID that is what will show on the canvas.

Selector color coding.

Selectors and selector specificity in CSS can take a little to get used to, but with this color coding system you will be an expert before you know it!

Selectors can be combined with a specific state of the element. For example, a class can style an element differently when the mouse cursor is positioned above the element.

In the image example an image overlay and button are made visible when hovered. To do this simply set the State dropdown to hover (this is also shown in the image in the next section).

Now it is just a matter of adjusting the style using the visual controls in the Style section (that we are now really really close to discussing…) to create the desired result. This can 'change’ be used in combination with CSS transitions for a really smooth effect.

The Reset function helps to keep the project code lean and clean. Wheter you applied styles to the wrong selector, accidentally designed for a different state, on the wrong breakpoint, or if you simply want to chance your approach, simply remove the styles you don’t need.

The dropdown gives a contextual overview of the all styles that have been applied. When class is selected from the Apply To dropdown, the associated class styles will be shown and can be removed. The hover styles are there in the hover state, breakpoint specific style when the breakpoint is active and so on.

Specific styles can be removed by clicking on them, or all styles can be whiped out at once. Whatever you do, don’t created a bloated style sheet with confliciting rules, clean up where needed!

The tool collections on the design pane have been organized in groups of related controls. Each of the groups (sections) can be collapsed an expanded when needed. When all the sections are expanded the scroll to the lower sections can be getting rather long...

Transitions — from one appearance to another — can only be created after the design is in place. So we skip those for now and go over the design tools found in each of the Style Control sections, starting with Typography.

The right choice of font, colors, and spacing greatly help to communicate the message of a website and contribute to the brand recognition. Bootstrap Builder features a big selection of font choices as well as a large set of typographic controls.

The Font drop down gives access to all the 808 font families in the Google font collection. A web safe (system) font can be selected just in case the primary selected font fails to load with the Fallback Font control.

The third dropdown can be used to select the font-weight. Some font famillies do not provide all options — in those cases the closest available option will be applied.

The next controls can be used to change the font-size and line-height for the active selector. These two properties can be specified in different units of measurement such as pixels (currently selected in the image) ems and rems. Clicking on the active unit will bring up a dropdown with other available options. 

The color of the font can be changed by clicking on the little color tile — white in the image — next to the drop. The text element can als be set to be displayed in italic and small caps.

The first set of Typography controls.

The last control visibile in the above image can be used to align the text. Left, right, center and justify are the available options.

Additional resources

• Editing, in-line formatting and linking text

There are a couple more typographical controls available. The text-transform control can be used to specify the capitalization of an element's text. It can be used to make text appear in all-uppercase, all-lowercase or with each word capitalized.

Text-decoration sets the text formatting for the selector to underline, overline, or line-through. Underline and overline decorations are positioned under the text, line-through over it.

The wrapping control is for handling the white-space inside the text element which has a big effect on how the text wraps.

The three different Spacing icons show the effect of each of the controls on the text. The text-indent controls the indentation of the first formatted line of the block. The second control adds space between all the letters of the text element. Space can be added between words with the word-spacing control.

More design possibilities for text elements.

The last control for styling text elements is for adding shadow effects.

The ability to add multiple font-shadows, and the ability to control the exact settings for each of them, allows for really cool effects.

The above effect is created using three text-shadows with slightly different settings for the blur and distance values. Higher values for Blur make the shadow wider and longer.

The offset-x and offset-y values specify the horizontal (X) and vertical (Y) distance the shadow is placed from the text. Negative values are allowed — a negative X value places the shadow to the left of the text, and negative Y value above the text.

The exact number of controls on the dimensions pane depends on the Element Type. On the right the controls for the image element are shown. Containers, for example, have a larger selection of dimension controls. Together with the ability to use a specific unit of measurement for each control, amazing layouts and effects can be created.

The width and height controls, including the minimum and maximum, work on the content area of an element. The content area is the part inside the padding, border, and margin of the element.

The Max-width tells the browser that an element can never become wider than the specified value. The Min-width does the contrary (and will override the Max-width setting) — it specifies a minimum for the width of an element. The height controls do the same for the height of an element.

The Padding controls the space between the content area of the element and the border. The space the padding takes up is part of the element and, for example, gets the same background color. The arrows denote where the padding will be applied, on the top, right, border or left side of the content area respectively.

Margin is the space between element. If an element is placed inside another element, the margin will push the (child) element away from the border of the parent element. A margin can also be a negative value.

One additional thing to know about Margin is that is can also be used to center elements within the parent container. Giving both the left and right margins the auto value will do the trick. This value is available by clicking on the unit switch dropdown.

Dimension controls and lenght units.

The same dropdown can be used to change the value type the dimension is specified in. Dimensions can be set in absolute pixel (px) values, or in relative values such as a percentage. Let’s look at that — how lenght can be defined in CSS — in a little more detail.

Pixels used to be a value that is normalized (the same) across devices and displays, but with the different new high resolutions screens that increasingly isn't true anymore. A pixel defined in CSS is now not necessarily the same as the pixels used by a device. Although an interesting topic, this is beyond the scope of this document.

Pixels used to be a value that is normalized (the same) across devices and displays, but with the different new high resolutions screens that increasingly isn't true anymore. A pixel defined in CSS is now not necessarily the same as the pixels used by a device. Although an interesting topic, this is beyond the scope of this document.

In a responsive design pixel values are mainly used for minimum and maxium width settings (if any) and for defining margins and paddings. For the default Width specification the auto and percentage values are most common.

When a dimension is specified in a percentage, the allotted space is calculated relative to the value of the parent element. This can be seen in the example below, the percentage bar will under all circumstances take up half of the grey column.

The vh and vw are two interesting units that are relatively new to the table in terms of good browser support. The first unit stands for Viewport Height and assign space relative to the height of the browser window. It can, for example, be used to create a cool effect with a background that takes up the full screen. This approach has been used in the Wave Weapons theme.

In the example below the width of the Viewport height bar is set relative to the height — when changing the height of the app (or browser window) you will see the width of the bar change accordingly.

The vw unit works the same, but is based upon the width of the viewport. The main use case is viewport based typography — the font can grow or shrink depending on the available space. The Wave Weapons theme showcases this as well. For dimensions this unit can be used to, for example, split screen design.

The  em and rem units allocate space relative to font size. In Bootstrap Builder this is (almost) always 16px for both units. However, a website visitor could set his default font size at a higher (or lower) value, causing the em and rem based dimensions to change with it.

The vmin and vmax values are whichever is smaller respectively larger of either the vh or vw values. This can come in handy but is currently not supported by all browsers.

Additional resources

• How CSS pixel size is calculated

This section is used to manage the elements placement on the canvas. Flex, floats, blocks, absolute overlays…the possibilities are endless! It is also why this might take a little to get used to, but with this write up, some additional info links and a tad of practice, you will soon be positioning elements like a boss.

The Float was originally intended for text wrapping around other elements such as pictures. Simply set Float to right for the image and the paragraph will wrap around it. When the image is increased in size or replaced by a larger one, the text automatically adjusts and reflows around it.

By default elements are not floating and behave as blocks. Adding a float will place these blocks next to eachother, if space permits.

The Clear is used in conjunction with floats. It can used be to move down (clear) the element following a floating element. Below you find a little example of the described behavior.

Floats work really well for many other layout constructs as well, including building an entire responsive grid system. However, they also come with a few peculiarities related. One of them can be seen at viewports widths below 440px — the Float C box will ‘float’ under B instaed of A.

The new CSS Flexbox Module provides a superior method for aligning, ordering, sizing and positioning elements. Yup, it can do all of that and therefore is increasingly being used instead of floats. Setting the Display control to Flex for a Column or Container will make all elements inside flex-children. These children will then listen to the flex settings of the parent, but can also get some individual flex styles. 

Let’s look at the other Display values in the next section before we start flexing things up.

Dimension controls and lenght units.

Additional resources

• Floats 101 on A List apart
• All about floats on CSS-Tricks

Most elements in Bootstrap Builder are displayed as block by default. This means that they will stack. In addition to floating, Display inline or inline-block can be used to place them next to each other. Another possibility would be to use flex for the parent. We will come back to using Flexbox in the next section.

Buttons and text-links are displayed as inline-blocks by default. Inline-blocks can not be centered using auto value for the margins. This can be done by setting the text-align property of the parent column or container to center. The example below shows this for the two inline-blocks. Again, using Flexbox would be another option, but we will get back to that… I promises!

The inline value works similar to inline-blocks but the element looses its height and width. This is not recommended for elements that contain other elements.

The Display none value is used to hide or show element under specific circumstances. One example would be to not show an illustrative element on small screens. Another example are elements that only appear following user interaction — modal dialogs and larger mobile navigations are usually only visible following the click of a button.

The elements of (un) ordered lists are displayed as list items. The remainder of the possible values relates to the use of tables. Because of their ‘width requirements’ tables can be a bit of an issue in a responsive design. One of the approaches would be to build a Flexbox Table — detailed guide can be found here.

Additional resources

• Design responsive tables with flexbox
  
• Aligning and centering block, inline-block and inline elements

A flex layout is created by setting the display property of a container element to flex. This can be any element that contains other elements, from a simple column or container, to a list element. The parent container becomes a flex-container, and all immediate children become flex-items.

The main characteristic of the flex container is the ability to modify the order, position, alignment, width or height of its children.

The Direction is used to define the direction the flex-items follow in the flex container. By default the flex-items will be positioned as (horizontal) Row. Changing the dropdown to Column will stack them.

The Wrap can be used to position a series of items on a single, or on multiple lines. If there is not enough space available, setting this property to wrap will place items that do not fit on the next line.

The Justify control determines how the elements are spaced out horizontally.

When there is more than a single line — more than a single column or row — of items, (align) Content can be used to distribute the space between the lines.

Using (align) Items the position of the elements on the cross axis of the defined direction can be managed.

Dimension controls and lenght units.

If you are reading this guide in Bootstrap Builder, you can play with these settings in the example below and get hands on experience in how they work. The container has a class of flex-parent with initial settings of Direction row to place them next to eachother and Justify flex-start to align them to the left. The Item center value perfectly centers them vertically

The flex-items also use the flex display property. This allows us to easily vertically center the text using the column Direction now with center for the Justify control.

The flex-items can also take on individual flexbox rules. The example below is an extension from the previous example, but now each of the containers have one additional class — fi-1 to fi-4 — so individual rules can be applied. Please make sure to deselect the other classes before doing so!

It will be immedialty clear that the blue box — item #4 — is now first in line. This is done with the Order control. Negative values can be used here as well, for fi-4 the -1 value puts it visually first in line.

The alignment specified by align-items on the parent container can be changed for individual flex items with the Align Self control. The black box has been pulled up by assigning the flex-start value to the fi-2 class. This overrides the center value specified on the parent.

The size of flex-items can be controlled with the Flex control. The Flex Basis specifies the initial size of a flex-item. This can be an absolute pixel value or a relative value like, for example, a percentage of the width of the parent.

The Flex Grow and  Flex Shrink controls are powerful tools that can be used to control the growth or reduction of the element based upon the available display space.

These controls can be used for additional control over the flex-items.

The image above shows the settings for the black box (flex-item #2). The initial width is not changed, the Flex Basis remains on auto. However, the Flex Grow setting tells the browser that the black box can take up 3 times as much of the remaining empty space as the other items.

Each of the items above has a different grow value, ranging from 1 to 4, causing the differences in width.

With the combination of Flex Basis and the unit switcher plus the Flex Grow control magical things can be achieved. In the example below the target (initial) value for each of the cards is set to 300px. When there is not enough room to get to that width, the item(s) will wrap.

They all have a Flex Grow value of 1 , so any remaining empty space will be distributed to them equally.

The result is that the sizing and positioning of the cards automagically adjusts to the available width and the height is maintained dynamically. Flexbox is an exteremely powerful layout tool. Therefore we created a comprehensive interactive guide with real world design examples of how to use Flexbox (in Bootstrap 4). We highly recommend checking it out!

Additional resources

• Design responsive tables with flexbox
  
• Add link to flexbox design guide

As discussed earlier, elements stack and float to the top right of the parent container most of the times. This behavior can be changed using floats, displaying the elment inline(-block) or using flexbox. The Position control can be used to define alternative rules for the positioning of an element.

Static — the first button — is the position value applied by the browser if no other value has been specified. These elements behave exactly as you would expect, according to the rules defined by the other controls. In the first row of the example below this is illustrated — four blocks, each 22% wide and 1% margin on the left and right are placed next to eachother using flex-direction: row.

Relative positioned elements behave very similar to static elements with two exceptions. Firstly , they can be moved around using offset values. The big difference with using margins for this is that other elements are displayed as if the element were in its normal position and taking up its normal space. The second row shows this — despite the dark block being visually out of position, the other blocks display exactly as in the row above.

Dimension controls and lenght units.

An absolute element can be positioned anywhere in the design using the same offset properties as relatively positioned elements. To do this inside of the current container or column, this parent container can not be positioned static.

Element that are positioned absolutely are taken out of the flow, taking up no space and not influencing the position of the other elements. Usually the z-index property is increased to make sure the element is visible on top of the other element. This is how dropdown menus are frequently created and illustrated in the third row. All types of cool stuff can be created with absolute positioned  elements.

An element with a fixed position uses the viewport (browser window) as its coordinate system. This means it always stays at the exact same position, also when the page is scrolled.

Additional resources

• Positioning: the icing on the CSS cake
  

When elements overlap, the Z-index determines which one covers the other. An element with a higher z-index covers an element with a lower one.

When a container has a specific height, there might not always be enough room for all the content to be displayed. With Overflow you can specify what needs to happen in that case. The content can be clipped or be allowed to overflow, which might impact elements below the container. The parent container can also be instructed to render scrollbars.

Vertical-align controls how inline elements are lined up vertically. The default value is baseline, which aligns the baseline of the element with the baseline of its parent.

The most common custom values are top, middle and bottom. The effect is shown in the examples below.

Stellar designs. Visually. CoffeeCup.

Stellar designs. Visually. CoffeeCup.

Stellar designs. Visually. CoffeeCup.

Please note that this CSS control does not allow you to vertically center an element within another element. Flexbox would be the tool of choice for that.

Additional resources

• What is Vertical Align?

The CSS multi-column layout is mostly thought of as a way to create print-inspired text columns. However, it's a very versatile tool that extends to other bigger and smaller areas of layout creation — it can be applied to containers as well as single text elements.

As an example, this is a single paragraph using the multi-column settings. Whenever there's enough room to divide the text over two columns that are (at least) 220px wide, the browser will do so.
If this paragraph shows as a single column, it means that there was not enough room for two 220px columns. The cool thing is that the text automatically flows between the columns ‚ when text is added or text flows due to width changes — to create (approximatly) the same height columns.

Count and Width are the most powerful tools. They control whether and how many columns will appear. Obviously, the Count sets the number of columns to a specific number. 

 The Width determines the minimum desired column width. If column-count is not also set, then the browser will automatically make as many columns as fit in the available width. Otherwise the browser will make columns of the specified width, with a maximum as defined by the Count.

The other controls enhance this core feature. The Gap let's you specifiy the space between the columns. A line can be drawn between the columns with the Rule control. The width, style and color can be specified as well.

When the multi-column is used on a container, elements inside can be instructed to span across all columns of the layout. Content before and after the element is still automatically balanced across columns before and after the element appears.

Multi-column layout settings are not limited to text and can be applied on parent containers as well. In the example below there's a bunch of cards that are flowing between different columns and for which the column count changes depending on the display width.

Dimension controls and lenght units.

Please note that in some browsers a tiny overflow effect can be vissible at certain widths.

Additional resources

• Using CSS multi-column layouts
  

The background of an element is the total size of the element, that includes padding and border. The margin is the space between elements and not included.

The web got a whole lot more interesting and beautifull with the new background properties introduced in CSS3. In addition to a simple solid backgrounds, beautiful full-size background-images can be applied. Background gradients can be declared in directly CSS. This offers better control over how the gradient is displayed as well as increased performance compared to using in image file.

Then there's the ability to use multiple-backgrounds. Combining images with overlaying semi-transparant gradients for example, can create really stunning effects.

The order in which these backgrounds are being applied is important for the desired effect. Generally speaking a gradient will need to be on top of an image, a small image on top of a larger image, etc.

The different background options.

The background up top in the control, will be visually on top in the canvas. To reorder the background layering you can grab one at the arrow icon, and drag it up or down to a different position. Clicking on a background will open it up to tweak the settings. Let's look at the gradient settings first.

A gradient is made of a progressive transition between two or more colors. A linear gradient follows a line on which the colors fade from one color into the next. A radial gradient starts at a center and changes colors going to the outside of the cirle (or ellipse) type of shape.

For a linear gradient the angle can be changed by specifying a specific Degree. For example, changing the value from 180 to 90 would make the gradient run from left to right instead if top to bottom. Any value inbetween is possible as well!

A gradient can consist of up to 4 colors. A Color can be added into the mix by clicking the checkbox. The Stop defines where the color starts. As can be seen in the example below, the colors don't have to transition, a 'hard-stop' can be created by giving two color stops the same value.

Please note that the color defaults to the color of the first stop, which is needed for the effect above.

The different background options.

Linear and radial gradients work in very similar ways, except the degree control is not available for radials.

Images can be added to the project or linked in from any online source. The Resource control provides these options. In the example below a local background image is used. To change it for an online image choose URL from the dropdown instead of Local Image, then paste the link to the image in the box that appears below. 

To change the image for a different project image, click on the edit icon. A dialog will come up from which a choice can be made between the various images in the existing collection in the project. New images can be added to the collection as well.

Images can also be changed at breakpoints, this way smaller and lighter images can be served to smaller devices (which frequently use less bandwidth).

The Position control can be used to move the image around. The default values are Left and Top. Custom values can be used as well — in the example the image has been moved so the surfer takes up a central position in the container.

The Attachment control specifies if the image's position is fixed within the viewport, or can scroll along with its containing block. The local setting means that if the element has a scrolling mechanism, the background scrolls with the element's contents.

The fixed setting works well for large background images on rows or wide columns as the Coast theme shows. Please note that mobile devices offer limited support for fixed backgrounds as it is (said to be) resource intensive and negatively impacts battery life. A good practice is to change from scroll to fixed for desktop devices, more or less on the right of the second Bootstrap breakpoint.

Small image patterns are frequently used to create a full background pattern. This is done using Repeat. In the example below a tiny thumbnail is instructed to repeat along both the x and y-axis. Alternavitely the image can be only repeated along the x or y-axis, or not at all.

The different background options.

The Size control offers many options for specifying the size of the background-image. Images can be scaled up or down, made to cover the entire background or be instructed to display entirely. It's a very useful control so let's have a more detailed look.

The default is Auto, which tells the browser to calculate the size based on the actual size of the image and its aspect ratio.

Frequently used for full-background sections, Cover tells the browser to make the image covers the entire container. Even if the images needs to be stretched or cut a little bit off (on the edges). This is especially handy in a responsive design where the size of the element or container with the background usually has a variable width (and/or lenght).

The Contain setting on the other hand, gives the instruction to always show the whole image, even if that leaves a little space to the sides or bottom.

A Custom size can be specified for the width, height or both. By unchecking either or both Auto boxes a value can be specified. Please note that this can easily influence the aspect ratio and cause distortion in the image — use with care!

With backgrounds frequently defined for containing elements, Origin and Clip are probably the least frequently used background controls.

The Origin defines where the top-left corner of the background starts. Starting with the outside part of the element, the background extends to the edge of the border using the border-box value. The padding-box setting makes the background start at the border (underneath the padding) using padding-box. 

When using content-box the background is restricted underneath the content area. Container type of elements don't have a content area and this setting will have no or minimal effect.

Clip works in a similar way, except it clips the background instead of resizing it.

Additional resources

• Scrolling, fixed and local background example
  

• Background patterns (and wave credit)
  

Borders can be added to elements using the Border control. Clicking on the circle in the center of the icon selects (or deselects) all borders. That does not mean that a border is enabled or disabled, it is just a way of selecting the border(s) for applying the style settings with the other controls. 

Multiple borders can be styled at the same time. In the image the top, right and left border have been selected and a border-width or 2px has been applied. The border-style is (a) fixed (line) and the specified color is orange.

The bottom border — deselected in the image — has the same style and color, but has a width of 6px. This can be seen by deselecting the other borders and clicking on the bottom border in the icon to select it. The example below shows the result of the border (and border-radius) definitions.

If borders are selected that have different styles applied, a red line is visible at the bottom of the controls for which the styles differ. If these styles are changed, they will be synchronized over all selected controls and the red line will disappear.

The different background options.

The different background options.

In terms of selecting the border, the Radius control works in the exact same way as the Border control. This control can be used to 'round' the corners of an element. It is not required for an element to have borders to do so, in the absence of a border this will be applied to the background of the element. 

The higher the value, the more rounded the corners. Setting different values for the horizontal (x) and vertical (y) part of the corner and/or for different corners can be used to create certain shapes.

To create a circle as seen in the flex card example, define an equal width and height, in combination with high radius values.

The effects sections consists of a number of controls that can add a nice touch to the initial appearance of a design. The controls also work great in combination with the hover and out of view states (the latter one coming to a public release soon...).

The below example uses a scale and rotate effect when the images, respectively the buttons, are hovered. To see the effect in Bootstrap Builder hit the Preview icon in the toolbar, then hover the example.

Camping

Sighting

The buttons use a little bit of box-shadow. This control is very similar to the text shadow control but, as the name implies, it works on the (element) box instead of the text.

In addition the shadow can be set on the inner element, inside the border. To do so simply click on the icon with the inward arrows. The Spread will will cause the shadow to expand and grow bigger.

The different background options.

Just like backgrounds and text-shadows, box-shadows can be layered. In combination with the different controls for positioing, sizing and coloring the shadows, this can create some cool effects. One more thing that's good to know: if a border-radius is specified, the box shadow takes on the same rounded corners.

The Scale control is part of the CSS transform toolset. It modifies the size of an element or group of elements, increasing or decreasing it.

The Translate function moves an element sideways, up and down, or a combination. This 'shift' it often used for hover or 'scroll into view' animations. There are two main reasons, firstly moving objects with translate does not affect the position of other objects, the rest of the UI will remain stable. Secondly, moving elements with translate is less CPU intensive and better for overall performance then, let's say, moving aboslutely positioned elements.

The different background options.

Elements can also be rotated. Rotate moves the element clockwise from its original position with positive values — negative values rotate it in the opposite direction.

The Skew transform tool 'tilts' an element one way or the other. It distordes the element by moving each point to the specified coordinates.

The Opacity tool defines the transparency of an element. The lower the value, the more of the background will 'shine through' the element. The value applies to the element as a whole, including the elements it contains.

Additional resources

• A Tale of Animation Performance
  

Elements or element groups are not always visible to the visitor and therefore also not always visible on the canvas. Examples include mobile menus that slide into view, accordions of which only one container is visible at a time, modal dialogs...up to simple dropdows.

The strike though eye icon next to an element in the tree indicates whether it is hidden on the canvas at the current breakpoint or state.

To show a hidden element — so it can be styled — just click on the icon. It will change to an eye and Bootstrap Builder will override the styles that hide the item. You can also do that for all elements on a page by clicking the 'Show x hidden item' toggle at the bottom of the pane.

Please note that under certain circumstances this may currently override applied positioning styles such as flexbox. This happens only when the eye 'forces' the visibility and will not happen for the published or exported site.

The CSS that is applied to the selected element is vissible in the bottom half of the inspector pane. By providing the CSS applied to the selected element at all breakpoints, the inspector gives you a sense of exactly what is going on "under the hood".

Just grab the handle to move the slider left or right and see the viewport and canvas change. You can also click on it and move it left or right pixel by pixel with the keyboard arrow keys.

Breakpoints are the places where layout or design changes are being made. They are represented by the little dots or 'points' above the Slider. The purple dots are the default breakpoints from the Bootstrap framework. The white dot is a custom breakpoint

A breakpoint is active when it lights up — when there's a little dark circle on top of the point. In the image above this is the fourth point from the left. A breakpoint becomes active when the slider is placed on the right of it and until the next breakpoint is reached.

Any layout or design changes they apply only as of that (break) point. They apply for all screens wider than the position of the active breakpoint but can be further changed any of the next breakpoints.

A simple example is provided below. A subgrid element is used to build a product card. The subgrid uses two rows, one for the product name with a single column that stretches the full width of the grid. The second row has two columns. Below the smallest breakpoint they stack and take up the full width, however, on the right of that breakpoint both columns are changed to a span 6.

This places the product image and description areas next to eachother. In Bootstrap Builder, select one of these columns and on the Layout pane see how the span number changes when moving through this breakpoint.

A couple of changes using the Design pane have been made to illustrate theat point as well. The font-size of the elements increases at this breakpoint (as well as at some of the other breakpoints) and some additional explanatory text is brought in when there's ample room on wide screens by changing the Display from none to block. 

There's a few more changes, as we have seen before, all added styles can be found in the CSS preview window on the Inspector pane. Another good method is peaking at the list in the Reset styles drop down. In short, all style rules can be updated at a breakpoint to create the best user experience for every device size.

Custom breakpoints can be added by clicking on the breakpoint line or with the plus icon on the left. They can be removed by selecting one — click on it — and hitting the minus icon. When selected they can also be moved left and right with the keyboard arrow keys. Please note that the default Bootstrap breakpoints can not be moved, nor removed.

The Zoom tool is placed on the left of the breakpoint buttons. Zooming out helps to design for large screens from smaller computers such as laptops and shows breakpoints that otherwise might be hidden behind the panes or even be offscreen.

The current viewport width — the position of the slider handle — is visible below the Zoom tool.

The three device icons on the right of that become brighter when the device type is more common at the current width. As desktop monitors, tablets, and phones all come in a variety of sizes, this is just for reference purposes. There is no specific phone or tablet width, nor is it possible to ‘design for phone’.

Instead, a responsive design has to look good and perform well at every width — the icons are merely an indication of what type of device might be used for viewing the site at the current position of the slider.

Additional resources

• Why you don't need device specific breakpoints
  

These functions are also available under the dropdpown menus and through keyboard shortcuts.

More coming soon

This places the product image and description areas next to eachother. Select one of these columns and on the Layout pane see how the span number changes when moving through this breakpoint.