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// scss-lint:disable QualifyingElement, DuplicateProperty
// Reboot
//
// Global resets to common HTML elements and more for easier usage by Bootstrap.
// Adds additional rules on top of Normalize.css, including several overrides.
// Reset the box-sizing
//
// Change from `box-sizing: content-box` to `border-box` so that when you add
// `padding` or `border`s to an element, the overall declared `width` does not
// change. For example, `width: 100px;` will always be `100px` despite the
// `border: 10px solid red;` and `padding: 20px;`.
//
// Heads up! This reset may cause conflicts with some third-party widgets. For
// recommendations on resolving such conflicts, see
// https://getbootstrap.com/getting-started/#third-box-sizing.
//
// Credit: https://css-tricks.com/inheriting-box-sizing-probably-slightly-better-best-practice/
html {
box-sizing: border-box;
}
*,
*::before,
*::after {
box-sizing: inherit;
}
// Make viewport responsive
//
// @viewport is needed because IE 10+ doesn't honor <meta name="viewport"> in
// some cases. See https://timkadlec.com/2012/10/ie10-snap-mode-and-responsive-design/.
// Eventually @viewport will replace <meta name="viewport">.
//
// However, `device-width` is broken on IE 10 on Windows (Phone) 8,
// (see https://timkadlec.com/2013/01/windows-phone-8-and-device-width/ and https://github.com/twbs/bootstrap/issues/10497)
// and the fix for that involves a snippet of JavaScript to sniff the user agent
// and apply some conditional CSS.
//
// See https://getbootstrap.com/getting-started/#support-ie10-width for the relevant hack.
//
// Wrap `@viewport` with `@at-root` for when folks do a nested import (e.g.,
// `.class-name { @import "bootstrap"; }`).
@at-root {
@-ms-viewport { width: device-width; }
}
//
// Reset HTML, body, and more
//
html {
// We assume no initial pixel `font-size` for accessibility reasons. This
// allows web visitors to customize their browser default font-size, making
// your project more inclusive and accessible to everyone.
// As a side-effect of setting the @viewport above,
// IE11 & Edge make the scrollbar overlap the content and automatically hide itself when not in use.
// Unfortunately, the auto-showing of the scrollbar is sometimes too sensitive,
// thus making it hard to click on stuff near the right edge of the page.
// So we add this style to force IE11 & Edge to use a "normal", non-overlapping, non-auto-hiding scrollbar.
// See https://github.com/twbs/bootstrap/issues/18543
// and https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/7165383/
-ms-overflow-style: scrollbar;
// Changes the default tap highlight to be completely transparent in iOS.
-webkit-tap-highlight-color: rgba(0,0,0,0);
}
body {
font-family: $font-family-base;
font-size: $font-size-base;
font-weight: $font-weight-base;
line-height: $line-height-base;
// Go easy on the eyes and use something other than `#000` for text
color: $body-color;
// By default, `<body>` has no `background-color` so we set one as a best practice.
background-color: $body-bg;
}
// Suppress the focus outline on elements that cannot be accessed via keyboard.
// This prevents an unwanted focus outline from appearing around elements that
// might still respond to pointer events.
//
// Credit: https://github.com/suitcss/base
[tabindex="-1"]:focus {
outline: none !important;
}
//
// Typography
//
// Remove top margins from headings
//
// By default, `<h1>`-`<h6>` all receive top and bottom margins. We nuke the top
// margin for easier control within type scales as it avoids margin collapsing.
h1, h2, h3, h4, h5, h6 {
margin-top: 0;
margin-bottom: .5rem;
}
// Reset margins on paragraphs
//
// Similarly, the top margin on `<p>`s get reset. However, we also reset the
// bottom margin to use `rem` units instead of `em`.
p {
margin-top: 0;
margin-bottom: 1rem;
}
// Abbreviations
abbr[title],
// Add data-* attribute to help out our tooltip plugin, per https://github.com/twbs/bootstrap/issues/5257
abbr[data-original-title] {
cursor: help;
}
address {
margin-bottom: 1rem;
font-style: normal;
line-height: inherit;
}
ol,
ul,
dl {
margin-top: 0;
margin-bottom: 1rem;
}
ol ol,
ul ul,
ol ul,
ul ol {
margin-bottom: 0;
}
dt {
font-weight: $dt-font-weight;
}
dd {
margin-bottom: .5rem;
margin-left: 0; // Undo browser default
}
blockquote {
margin: 0 0 1rem;
}
//
// Links
//
a {
color: $link-color;
text-decoration: $link-decoration;
@include hover-focus {
color: $link-hover-color;
text-decoration: $link-hover-decoration;
}
}
// And undo these styles for placeholder links/named anchors (without href)
// which have not been made explicitly keyboard-focusable (without tabindex).
// It would be more straightforward to just use a[href] in previous block, but that
// causes specificity issues in many other styles that are too complex to fix.
// See https://github.com/twbs/bootstrap/issues/19402
a:not([href]):not([tabindex]) {
color: inherit;
text-decoration: none;
@include hover-focus {
color: inherit;
text-decoration: none;
}
&:focus {
outline: 0;
}
}
//
// Code
//
pre {
// Remove browser default top margin
margin-top: 0;
// Reset browser default of `1em` to use `rem`s
margin-bottom: 1rem;
// Normalize v4 removed this property, causing `<pre>` content to break out of wrapping code snippets
overflow: auto;
}
//
// Figures
//
figure {
// Normalize adds `margin` to `figure`s as browsers apply it inconsistently.
// We reset that to create a better flow in-page.
margin: 0 0 1rem;
}
//
// Images
//
img {
// By default, `<img>`s are `inline-block`. This assumes that, and vertically
// centers them. This won't apply should you reset them to `block` level.
vertical-align: middle;
// Note: `<img>`s are deliberately not made responsive by default.
// For the rationale behind this, see the comments on the `.img-fluid` class.
}
// iOS "clickable elements" fix for role="button"
//
// Fixes "clickability" issue (and more generally, the firing of events such as focus as well)
// for traditionally non-focusable elements with role="button"
// see https://developer.mozilla.org/en-US/docs/Web/Events/click#Safari_Mobile
[role="button"] {
cursor: pointer;
}
// Avoid 300ms click delay on touch devices that support the `touch-action` CSS property.
//
// In particular, unlike most other browsers, IE11+Edge on Windows 10 on touch devices and IE Mobile 10-11
// DON'T remove the click delay when `<meta name="viewport" content="width=device-width">` is present.
// However, they DO support removing the click delay via `touch-action: manipulation`.
// See:
// * https://v4-alpha.getbootstrap.com/content/reboot/#click-delay-optimization-for-touch
// * http://caniuse.com/#feat=css-touch-action
// * https://patrickhlauke.github.io/touch/tests/results/#suppressing-300ms-delay
a,
area,
button,
[role="button"],
input,
label,
select,
summary,
textarea {
touch-action: manipulation;
}
//
// Tables
//
table {
// No longer part of Normalize since v4
border-collapse: collapse;
// Reset for nesting within parents with `background-color`.
background-color: $table-bg;
}
caption {
padding-top: $table-cell-padding;
padding-bottom: $table-cell-padding;
color: $text-muted;
text-align: left;
caption-side: bottom;
}
th {
// Centered by default, but left-align-ed to match the `td`s below.
text-align: left;
}
//
// Forms
//
label {
// Allow labels to use `margin` for spacing.
display: inline-block;
margin-bottom: .5rem;
}
// Work around a Firefox/IE bug where the transparent `button` background
// results in a loss of the default `button` focus styles.
//
// Credit: https://github.com/suitcss/base/
button:focus {
outline: 1px dotted;
outline: 5px auto -webkit-focus-ring-color;
}
input,
button,
select,
textarea {
// Normalize includes `font: inherit;`, so `font-family`. `font-size`, etc are
// properly inherited. However, `line-height` isn't inherited there.
line-height: inherit;
}
input[type="radio"],
input[type="checkbox"] {
// Apply a disabled cursor for radios and checkboxes.
//
// Note: Neither radios nor checkboxes can be readonly.
&:disabled {
cursor: $cursor-disabled;
}
}
input[type="date"],
input[type="time"],
input[type="datetime-local"],
input[type="month"] {
// Remove the default appearance of temporal inputs to avoid a Mobile Safari
// bug where setting a custom line-height prevents text from being vertically
// centered within the input.
// See https://bugs.webkit.org/show_bug.cgi?id=139848
// and https://github.com/twbs/bootstrap/issues/11266
-webkit-appearance: listbox;
}
textarea {
// Textareas should really only resize vertically so they don't break their (horizontal) containers.
resize: vertical;
}
fieldset {
// Browsers set a default `min-width: min-content;` on fieldsets,
// unlike e.g. `<div>`s, which have `min-width: 0;` by default.
// So we reset that to ensure fieldsets behave more like a standard block element.
// See https://github.com/twbs/bootstrap/issues/12359
// and https://html.spec.whatwg.org/multipage/#the-fieldset-and-legend-elements
min-width: 0;
// Reset the default outline behavior of fieldsets so they don't affect page layout.
padding: 0;
margin: 0;
border: 0;
}
legend {
// Reset the entire legend element to match the `fieldset`
display: block;
width: 100%;
padding: 0;
margin-bottom: .5rem;
font-size: 1.5rem;
line-height: inherit;
}
input[type="search"] {
// This overrides the extra rounded corners on search inputs in iOS so that our
// `.form-control` class can properly style them. Note that this cannot simply
// be added to `.form-control` as it's not specific enough. For details, see
// https://github.com/twbs/bootstrap/issues/11586.
-webkit-appearance: none;
}
// todo: needed?
output {
display: inline-block;
// font-size: $font-size-base;
// line-height: $line-height;
// color: $input-color;
}
// Always hide an element with the `hidden` HTML attribute (from PureCSS).
[hidden] {
display: none !important;
}
|
