* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
}

.rainbow {
  min-height: 100vh;
  display: grid;
  grid-template-rows: repeat(7, minmax(70px, 1fr));
}

.color {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: clamp(1rem, 3vw, 1.5rem);
  font-weight: 700;
  color: #fff;
}

.red { background-color: #ff0000; }
.orange { background-color: #ff7f00; }
.yellow { background-color: #ffdd00; color: #1f1f1f; }
.green { background-color: #00a651; }
.blue { background-color: #0072ce; }
.indigo { background-color: #4b0082; }
.violet { background-color: #8f00ff; }