blog/src/styles/_mixins.scss

@import 'variables';

// Centering Blocks
/////////////////////////////////////

@mixin aligncenter() {
    display: block;
    margin-left: auto;
    margin-right: auto;
}

// Toggling content
/////////////////////////////////////

// Hide from both screenreaders and browsers: h5bp.com/u
@mixin hide() {
    display: none !important;
    visibility: hidden;
}

@mixin show() {
    display: block;
    visibility: visible;
}

// Hide only visually, but have it available for screenreaders: h5bp.com/v
@mixin visuallyhidden() {
    border: 0;
    clip: rect(0 0 0 0);
    height: 1px;
    margin: -1px;
    overflow: hidden;
    padding: 0;
    position: absolute;
    width: 1px;

    // Extends the .visuallyhidden class to allow the
    // element to be focusable when navigated to via the keyboard: h5bp.com/p
    &.focusable:active,
    &.focusable:focus {
        clip: auto;
        height: auto;
        margin: 0;
        overflow: visible;
        position: static;
        width: auto;
    }
}

// Hide visually and from screenreaders, but maintain layout
@mixin invisible() {
    visibility: hidden;
}

// CSS image replacement
/////////////////////////////////////

@mixin hide-text() {
    font: 0/0 a; // stylelint-disable font-family-no-missing-generic-family-keyword
    color: transparent;
    text-shadow: none;
    background-color: transparent;
    border: 0;
}

// Text overflow
/////////////////////////////////////

@mixin ellipsis() {
    text-overflow: ellipsis;
    overflow: hidden;
    white-space: nowrap;
}

// Default transition
/////////////////////////////////////

@mixin transition() {
    transition: all ease-in-out .15s;
}

// Dashed Dividers
/////////////////////////////////////

@mixin divider() {
    position: relative;
    border-bottom: 1px dashed lighten($brand-grey-light, 20%);
    margin-top: $spacer * $line-height;
    margin-bottom: $spacer * $line-height;

    &::before {
        content: '';
        position: absolute;
        left: 0;
        height: 1px;
        bottom: -2px;
        width: 100%;
        border-bottom: 1px dashed #fff;
    }
}

@mixin divider-top() {
    position: relative;
    border-top: 1px dashed lighten($brand-grey-light, 20%);
    margin-top: $spacer * $line-height;
    margin-bottom: $spacer * $line-height;

    &::after {
        content: '';
        position: absolute;
        left: 0;
        height: 1px;
        top: 0;
        width: 100%;
        border-bottom: 1px dashed #fff;
    }
}

// Heading band
/////////////////////////////////////

@mixin heading-band() {
    display: inline-block;
    background: rgba(255, 255, 255, .5);
    padding: ($spacer/2) $spacer ($spacer/2) 100%;
    margin-left: -100%;
}

// Layout breakout
/////////////////////////////////////

@mixin breakoutviewport() {
    margin-left: calc(-50vw + 50%);
    margin-right: calc(-50vw + 50%);

    @media (min-width: $screen-md) {
        @include breakoutviewport--base();
    }
}

@mixin breakoutviewport--base() {
    margin-left: -($spacer * 4);
    margin-right: -($spacer * 4);
}

@mixin breakoutviewport--full() {
    margin-left: calc(-50vw + 50%);
    margin-right: calc(-50vw + 50%);
}

// Button sizing
/////////////////////////////////////

@mixin button-size(
    $padding-vertical,
    $padding-horizontal,
    $font-size,
    $line-height,
    $border-radius
) {
    padding: $padding-vertical $padding-horizontal;
    font-size: $font-size;
    line-height: $line-height;
    border-radius: $border-radius;
}

// Form control sizing
/////////////////////////////////////

@mixin input-size(
    $padding-vertical,
    $padding-horizontal,
    $font-size,
    $line-height,
    $border-radius
) {
    padding: $padding-vertical $padding-horizontal;
    font-size: $font-size;
    line-height: $line-height;
    border-radius: $border-radius;

    &input[type='search'] {
        background-size: $font-size;
        background-position: $padding-vertical center;
        padding-left: ($padding-vertical * 4);
    }

    &select {
        line-height: $input-height;
    }

    &textarea,
    &select[multiple] {
        height: auto;
    }
}

// Placeholder text
/////////////////////////////////////

@mixin placeholder($color: $input-color-placeholder) {
    &::-moz-placeholder {
        color: $color;
        opacity: 1; // Override Firefox's unusual default opacity; See https//github.com/twbs/bootstrap/pull/11526
    }

    &::-webkit-input-placeholder {
        color: $color;
    }

    &:-ms-input-placeholder {
        color: $color;
    }
}

// Image frame style
/////////////////////////////////////

@mixin media-frame() {
    @include transition();

    border-top: 2px solid transparent;
    border-bottom: 2px solid transparent;
    border-radius: $border-radius;
    box-shadow: 0 1px 3px rgba($brand-grey, .2);

    @media (min-width: $screen-sm) {
        border: 2px solid transparent;
    }
}