body {
  font-family: sans-serif;
}

.container {
  display: flex;
  align-items: center;
  flex-direction: column;
  gap: 10px;
}

.header {
  width: 750px;
  padding: 30px 10px;
}

.border {
  border: 2px solid black;
}

.nav {
  width: 750px;
  padding: 10px;
}

.thumb-content {
  display: flex;
  gap: 10px;
}

.content {
  position: relative;
  width: 500px;
  height: 300px;
  padding: 50px 1px;
}

.sidebar {
  width: 250px;
  height: 300px;
  padding: 50px 1px;
}

.footer {
  width: 750px;
  padding: 20px 10px;
}

.text {
  margin: 0;
  text-transform: uppercase;
  font-size: 20px;
  font-weight: 700;
  text-align: center;
}

.square {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 100px;
  height: 100px;

  background-color: red;

  transform: translate(-50%, -50%);
  animation: rotateColor 5s linear infinite;
}

@keyframes rotateColor {
  0% {
    background-color: red;
    transform: translate(-50%, -50%) rotate(0deg);
  }
  50% {
    background-color: orange;
    transform: translate(-50%, -50%) rotate(180deg);
  }
  100% {
    background-color: green;
    transform: translate(-50%, -50%) rotate(360deg);
  }
}