style.css

@import url(https://fonts.googleapis.com/css?family=Open+Sans+Condensed:300,300italic,700);
:root {
  --primary: hsl(1275, 100%, 50%);
  --complimentary: hsl(149, 100%, 50%);
  --degs: 0.25turn;
}

body {
  margin: 0;
  height: 100vh;
  display: grid;
  grid-template-rows: auto 1fr;
  font-family: 'Open Sans Condensed', sans-serif;
}

.gradient {
  height: 100%;
  width: 100%;
  grid-column: 1 / -1;
  background: -webkit-gradient(linear, left top, left bottom, from(var(--degs)), color-stop(var(--primary)), to(var(--complimentary)));
  background: linear-gradient(var(--degs), var(--primary), var(--complimentary));
  display: grid;
  grid-template-rows: 1fr 1fr;
  grid-template-columns: repeat(5, auto);
  justify-items: center;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: end;
}

header {
  grid-row: 1;
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: auto 1fr;
  width: 100%;
  height: 70px;
  justify-items: end;
  align-items: center;
  background: #ededed;
}

header * {
  margin: 0 10px 0 10px;
}

.gradient:active > * {
  display: none;
}

button {
  position: absolute;
  border: none;
  height: 50px;
  width: 100px;
}

#pastel {
  bottom: 20%;
  right: 20%;
}

#normal {
  bottom: 20%;
  left: 20%;
}

#modal {
  position: absolute;
  left: 15%;
  top: 35%;
  display: grid;
  height: 45%;
  width: 70%;
  background: #ebebeb;
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  -ms-flex-line-pack: center;
  align-content: center;
  z-index: 1;
}

@media screen and (max-width: 800px) {
  h1 {
    font-size: 1rem;
  }
  h2 {
    font-size: 0.8rem;
  }
}