body {
  color: #5b595b;
  margin: 0;
}

/* reset */
button {
  border: none;
  padding: 15px 20px;
  background-color: #dddbdd;
  font-size: 16px;
  letter-spacing: 0.25px;
  position: relative;
  outline: none;
}

.container {
  max-width: 1000px;
  margin: auto;
  padding: 1em;
}

.top-space {
  margin-top: 2em;
}

/* underline animation */
.underline:before {
  position: absolute;
  content: '';
  width: 0%;
  height: 4px;
  background-color: #1d8bc9;
  bottom: 0;
  left: 50%;
  transition: all 0.3s;
}

.underline:hover:before {
  left: 0;
  width: 100%;
}

/* bounce animation*/
.bounce span {
  position: absolute;
  width: 0%;
  height: 100%;
  left: 0;
  top: 0;
  transition-property: all;
  transition-delay: 0.3;
  transition-duration: 0.3s;
  background-color: #1d8bc9;
}

.bounce:hover span {
  width: 100%;
}

.bounce div {
  position: relative;
  transition: color 0.3s ease-in-out;
}

.bounce:hover div {
  color: #fff;
}

/* buzz animation */
.buzz:hover {
  animation: buzz 0.5s;
}

@keyframes buzz {
  0% {
    transform: rotate(-2deg);
  }
  50% {
    transform: rotate(2deg);
  }
  75% {
    transform: rotate(-4deg);
  }
  100% {
    transform: rotate(4deg);
  }
}

/* bounce in */
.bounce-in:hover {
  animation-name: bounce;
  animation-duration: 0.75s;
  animation-timing-function: ease-in-out;
  animation-fill-mode: backwards;
}

@keyframes bounce {
  0% {
    transform: scale(1.3);
  }

  70% {
    transform: scale(1.25);
  }

  100% {
    transform: scale(1.3);
  }
}