html {
  box-sizing: border-box;
  font-family: 'Arial Rounded MT Bold', 'Helvetica Rounded', Arial, sans-serif;
}

*,
*:before,
*:after {
  box-sizing: inherit;
}

h2 {
  text-align: center;
}

body {
  margin: 0;
  min-height: 100vh;
  background: linear-gradient(
      45deg,
      hsla(340, 100%, 55%, 1) 0%,
      hsla(340, 100%, 55%, 0) 70%
    ),
    linear-gradient(
      135deg,
      hsla(225, 95%, 50%, 1) 10%,
      hsla(225, 95%, 50%, 0) 80%
    ),
    linear-gradient(
      225deg,
      hsla(140, 90%, 50%, 1) 10%,
      hsla(140, 90%, 50%, 0) 80%
    ),
    linear-gradient(
      315deg,
      hsla(35, 95%, 55%, 1) 100%,
      hsla(35, 95%, 55%, 0) 70%
    );
}

h2 {
  margin-top: 0;
  padding-top: 0.8em;
}

nav {
  position: relative;
  perspective: 600px;
}

.cool > li > a {
  color: yellow;
  text-decoration: none;
  font-size: 20px;
  background: rgba(0, 0, 0, 0.2);
  padding: 10px 20px;
  display: inline-block;
  margin: 20px;
  border-radius: 5px;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: center;
}

.cool > li {
  position: relative;
  display: flex;
  justify-content: center;
}

.dropdown {
  opacity: 0;
  position: absolute;
  overflow: hidden;
  padding: 20px;
  top: -20px;
  border-radius: 2px;
  transition: all 0.5s;
  transform: translateY(100px);
  will-change: opacity;
  display: none;
}
/* pod spodem dodane */
.trigger-enter .dropdown {
  display: block;
}
.trigger-enter-active .dropdown {
  opacity: 1;
}
/* dotąd */

.dropdownBackground {
  width: 100px;
  height: 100px;
  position: absolute;
  background: #fff;
  border-radius: 4px;
  box-shadow: 0 50px 100px rgba(50, 50, 93, 0.1),
    0 15px 35px rgba(50, 50, 93, 0.15), 0 5px 15px rgba(0, 0, 0, 0.1);
  transition: all 0.3s, opacity 0.1s, transform 0.2s;
  transform-origin: 50% 0;
  display: flex;
  justify-content: center;
  opacity: 0;
}

/* pod spodem dodane */
.dropdownBackground.open {
  opacity: 1;
}
/* dotąd */

.arrow {
  position: absolute;
  width: 20px;
  height: 20px;
  display: block;
  background: white;
  transform: translateY(-50%) rotate(45deg);
}

.bio {
  min-width: 500px;
  display: flex;
  justify-content: center;
  align-items: center;
  line-height: 1.7;
}

.bio img {
  float: left;
  margin-right: 20px;
}

.courses {
  min-width: 300px;
}

.courses li {
  padding: 10px 0;
  display: block;
  border-bottom: 1px solid rgba(0, 0, 0, 0.2);
}

.dropdown a {
  text-decoration: none;
  color: #ffc600;
}

a.button {
  background: black;
  display: block;
  padding: 10px;
  color: white;
  margin-bottom: 10px;
}

/* Matches Twitter, TWITTER, twitter, tWitter, TWiTTeR... */
.button[href*='twitter'] {
  background: #019fe9;
}
.button[href*='io'] {
  background: #ffc600;
}