Helpers
/scss/main/_variables.scss
/scss/main/_dimentions.scss
/scss/main/_helpers.scss
/scss/components/_media.scss

Special classes for adaptive markup

.hide-md-under {display: none; } for window width <= md
.hide-md-over {display: none; } for window width > md
.show-md-under {display: block; } for window width <= md
.show-md-over {display: block; } for window width > md
.right-md {float: right; } for window width > md
.center-md {display: table; margin-left: auto; margin-right: auto; } for window width<= md
.text-md-right {text-align: right; } for window width > md
.text-md-center {text-align: center; } for window width <= md

General classes

Size and space
.full Set up with=100%
.nm No margin
.np No padding
.m{...8} Margin {number} * 16px
.ml{...8} .mr{...8}
.mt{...8} .mb{...8}
Margin left, right, top, bottom
additionally: .ml => margin-left: 8px; etc.
.p{...8} Padding {number} * 16px
.pl{...8} .pr{...8}
.pt{...8} .pb{...8}
Padding left, right, top, bottom
additionally: .pr => padding-right: 8px; etc.
.box0 Box0 (padding: 8px)
.box Box (padding: 16px)
.box2 Box2 (padding: 32px)
.square > .inner Square responsive block
.flex-middle Align content to center using flex
.flex-valign Vertical and left align using flex
.flex-valign-end Vertical and right align using flex
.flex-bottom Align content to bottom and left using flex
.flex-bottom-right Align content to bottom and right using flex
Position
.fixed Fixed
.absolute Absolute
.relative Relative
.fill .top-left .top-right .bottom-left .bottom-right Positions for .fixed and .absolute
.z0 .z1 .z100 .z1000 .z9999 Z-index for .fixed and .absolute
Edges
.rounded-{1...10} Border radius, PX
.shadow-{1...5} Shadow
.border .border-right .border-left .border-top .border-bottom Border (default -> width: 1px, color: light)
.nb .nb-l
.nb-r .nb-t .nb-b
No border on all, left, right, top, bottom
.circle Circle (always is an inline-block)
Images / Video
.background Background (center, no-repeat)
.background.bg-left Background (left, no-repeat)
.background.bg-right Background (right, no-repeat)
.cover Background (cover)
.image Wrapper for img tag
.hover-scale Scale effect fot img (wrapper)
.video.ratio-16-9 .video.ratio-4-3 Responsive wrapper for iframe tag