Туры выходного дня
по ЮГУ России

html * {
box-sizing: border-box;
}

body {
font-size: 16px;
padding: 10px;
background: #333333;
color: #ffffff;
text-align: center;
height: 100vh;
margin: 0;
display: flex;
align-items: center;
height: 100vh;
}

.container {
width: 100%;
}

.border-animation {
--border-width: 0.1em;
--animation-speed: 0.5s;
--color: #ffffff;
color: var(--color);
position: relative;
display: inline-block;
font-size: 4em;
line-height: 1em;
transform: scale(1, 0.8);
border: var(--border-width) solid transparent;

.border-animation__inner {
position: relative;
display: inline-block;
width: 100%;
font-family: 'Six Caps', sans-serif;
font-weight: 300;
text-transform: uppercase;
letter-spacing: 0.05em;
cursor: pointer;
padding: 0.2em;
// background: rgba(50, 50, 50, 0.5);
background: #333;
z-index: 1;
border: solid var(--border-width) transparent;
}

&:before,
&:after {
content: '';
position: absolute;
background: var(--color);
}

&:focus:before,
&:hover:before {
animation: beforeBorders var(--animation-speed) forwards ease-in-out;
}

&:focus:after,
&:hover:after {
animation: afterBorders var(--animation-speed) forwards ease-in-out;
}

&:focus,
&:hover {
animation: borderColors var(--animation-speed) steps(1) forwards;
outline: none;

.border-animation__inner {
animation: background calc(var(--animation-speed) / 5 * 3) forwards ease-in-out;
animation-delay: calc(var(--animation-speed) / 5 * 2);
}
}
}

@keyframes beforeBorders {
0% {
top: calc(var(--border-width) * -1);
left: 50%;
bottom: auto;
right: auto;
width: 0;
height: var(--border-width);
}
33% {
top: calc(var(--border-width) * -1);
left: calc(var(--border-width) * -1);
bottom: auto;
right: auto;
width: calc(var(--border-width) + 50%);
height: var(--border-width);
}
66% {
top: calc(var(--border-width) * -1);
left: calc(var(--border-width) * -1);
bottom: auto;
right: auto;
width: var(--border-width);
height: calc((var(--border-width) * 2) + 100%);
}
100% {
top: auto;
left: calc(var(--border-width) * -1);
bottom: calc(var(--border-width) * -1);
right: auto;
width: calc(var(--border-width) + 50%);
height: calc((var(--border-width) * 2) + 100%);
}
}

@keyframes afterBorders {
0% {
top: calc(var(--border-width) * -1);
left: auto;
bottom: auto;
right: 50%;
width: 0;
height: var(--border-width);
}
33% {
top: calc(var(--border-width) * -1);
left: auto;
bottom: auto;
right: calc(var(--border-width) * -1);
width: calc(var(--border-width) + 50%);
height: var(--border-width);
}
66% {
top: calc(var(--border-width) * -1);
left: auto;
bottom: auto;
right: calc(var(--border-width) * -1);
width: var(--border-width);
height: calc((var(--border-width) * 2) + 100%);
}
100% {
top: auto;
left: auto;
bottom: calc(var(--border-width) * -1);
right: calc(var(--border-width) * -1);
width: calc(var(--border-width) + 50%);
height: calc((var(--border-width) * 2) + 100%);
}
}

@keyframes borderColors {
0% {
border-top-color: transparent;
border-right-color: transparent;
border-bottom-color: transparent;
border-left-color: transparent;
}
33% {
border-top-color: var(--color);
border-right-color: transparent;
border-bottom-color: transparent;
border-left-color: transparent;

}
66% {
border-top-color: var(--color);
border-right-color: var(--color);
border-bottom-color: transparent;
border-left-color: var(--color);
}
100% {
border-top-color: var(--color);
border-right-color: var(--color);
border-bottom-color: var(--color);
border-left-color: var(--color);
}
}

@keyframes background {
to {
background: #555;
text-shadow: 0 0.1em 0.1em #111;
}
}

@media (min-width: 850px) {
body {
justify-content: center;
}
}

@media (min-width: 1200px) {
.border-animation {
font-size: 6em;
line-height: 1em;
}
}