arkadylukashov/Fixed footer

## Fixed footer
<body>
    <header>...</header>
    <main>...</main>
    <footer>...</footer>
</body>

## Fixed footer styles
body {
    display: flex;
    min-height: 100vh;
    flex-direction: column;
}

main {
    flex: 1;
}
@media screen and (-ms-high-contrast: active), (-ms-high-contrast: none) {
	main {
	  flex: none !important;
	  -ms-flex: none !important;
	}
}