<nav>
  <a class="link" href="#">Home</a>
  <a class="link" href="#">About</a>
  <a class="link" href="#">Contact</a>
</nav>

nav {
  padding: 24px;
  text-align: center;
  font-family: Raleway;
  box-shadow: 2px 2px 8px rgba(0, 0, 0, 0.5);
  background: #3fa46a;
}
.link {
  transition: 0.7s ease;
  color: #fff;
  font-size: 20px;
  text-decoration: none;
  border-top: 4px solid #3fa46a;
  border-bottom: 4px solid #3fa46a;
  padding: 20px 0;
  margin: 0 20px;
}
.link:hover {
  border-top: 4px solid #ffffff;
  border-bottom: 4px solid #ffffff;
  padding: 6px 0; 
}

<div class="box">
  <div class="hid-box">
</div>

.box {
  height: 90px;
  width: 100px;
  margin: auto;
  overflow: hidden;
  background: #b6feb4;
  cursor: pointer;
}
.hid-box {
  top: 100%;
  position: relative;
  transition: all .7s ease-out;
  background: #b8dbf1;
  height: 100%;
}
.box:hover > .hid-box{
  top: 0;
}

<div id="outer">
  <div class="slide left">SLIDE INSIDE </div>
  <div class="slide diagonal">SLIDE DIAGONAL </div>
</div>

body {background: #162944;}
.slide {
  font-family: sans-serif;
  color: #FFF;
  border: 2px solid rgb(216, 2, 134);
  padding: 18px 36px;
  font-size: 14px;
  cursor: pointer;
  box-shadow: inset 0 0 0 0 #D80286;
  -webkit-transition: ease-out 1s;
  transition: ease-out 1s;
}
.left:hover {
  box-shadow: inset 0 0 0 50px #D80286;
}
.diagonal:hover {
  box-shadow: inset 400px 50px 0 0 #D80286;
}
#outer {
  display: flex;
  justify-content: space-between;
  width: 400px;
  margin: 100px auto;
}

<h1>Mousemove</h1>

h1{
  font-size:72px;
  font-family:'Verdana';
  text-align:center;
  text-transform:uppercase;
}

jQuery(document).ready(function(){
   $('h1').mousemove(function(e){
     var rXP = (e.pageX - this.offsetLeft-$(this).width()/2);
     var rYP = (e.pageY - this.offsetTop-$(this).height()/2);
     $('h1').css('text-shadow', +rYP/10+'px '+rXP/80+'px rgba(227,6,19,.8), '+rYP/8+'px '+rXP/60+'px rgba(255,237,0,1), '+rXP/70+'px '+rYP/12+'px rgba(0,159,227,.7)');
   });
});

<div class="spinner"></div>

@property --a {
  syntax: '<angle>'; 
  initial-value: 0deg;
  inherits: false
}
body { display: grid;}
.spinner {
  box-sizing: border-box; 
  place-self: center; 
  width: min(100%, 18em); 
  aspect-ratio: 1; 
  padding: 1.25em;
  border-radius: 50%; 
  box-shadow: 2px 2px 17px #000;
  background: url(https://s3-us-west-2.amazonaws.com/s.cdpn.io/2017/17_05_a_amur_leopard_14.jpg) 
      50%/ cover content-box, 
    conic-gradient(in hsl longer hue from var(--a), hsl(0, 100%, 80%) 0 0);
  animation: spin 2s linear infinite;
}
@keyframes spin { to { --a: 1turn } }

<button>Hover Me!</button>

@property --r {
  syntax: '<length-percentage>';
  initial-value: 0px;
  inherits: false
}
button {
  place-self: center;
  border: solid 2px #0001;
  padding: 0 1em;
  display: block;
  margin: 200px auto;
  border-radius: 2em;
  box-shadow: inset 1px 3px 1px #fff4;
  background: radial-gradient(circle at var(--x, 0%) var(--y, 0%), black calc(var(--r) - 1px), darkorange var(--r)) border-box;
  color: white;
  font: 1.5em/ 2.25 ubuntu, sans-serif;
  transition: --r .35s;

  &:hover { --r: 100% }
}

function update_position(e) {
  let _t = e.target;
  if(_t.tagName.match(/^button$/i)) {
    let r = _t.getBoundingClientRect();
    ['x', 'y'].forEach(c => 
      _t.style.setProperty(`--${c}`, `${e[`client${c.toUpperCase()}`] - r[c]}px`))
  }
}
addEventListener('mouseover', update_position);
addEventListener('mouseout', update_position)

<h1><span>Подпишись на телеграмм канал @code_ready</span></h1>

h1 {
  position: relative;
  width: 18em;
  margin: 3em auto;
  padding: .7em 0;
  font: normal 800 1.4em / 1.5 sans-serif;
  text-align: center;
  text-transform: uppercase;
}
span {
  box-shadow: inset 0 0 0 5em white, 0 0 0 .2em white;
}
h1:before {
  content: '';
  position: absolute;
  top: 0;
  right: 11%;
  bottom: 0;
  left: 11%;
  z-index: -1;
  border: 3px solid coral;
}