// BASIC MIXINS
// --------------------------------------------------------------------
// Horizontal centering
@mixin center-horizontal($width) {
    margin-left: auto;
    margin-right: auto;
    width: $width;
}

// Vertical centering
// zerosixthree.se/vertical-align-anything-with-just-3-lines-of-css/
// parent element needs a defined height; use w/ .csstransforms
@mixin center-vertical() {
    position: relative;
    top: 50%;
    transform: translateY(-50%);
}

// BASIC MIXINS
// --------------------------------------------------------------------
// Horizontal centering
@mixin center-horizontal($width: 100%) {
    margin-left: auto;
    margin-right: auto;
    width: $width;
}

// Vertical centering
// zerosixthree.se/vertical-align-anything-with-just-3-lines-of-css/
// parent element needs a defined height; use w/ .csstransforms
@mixin center-vertical() {
    position: relative;
    top: 50%;
    transform: translateY(-50%);
}

Add fallback for center-horizontal mixin.
Add fallback for center-horizontal mixin.
