body {
  margin: 0;
  padding: 0;
  background-color: #1e1f20;
  color: #e3e3e3;
}

.root {
  display: flex;
  height: 100vh;
  width: 100vw;
}

nav {
  flex: 1;
  background-color: #131314;
  padding: 20px;
  border-right: 1px solid #333;
}

nav ul {
  list-style: none;
  padding: 0;
}

nav li {
  margin-bottom: 10px;
}

nav a {
  color: #e3e3e3;
  text-decoration: none;
  display: block;
  padding: 12px 16px;
  border-radius: 8px;
  transition: background-color 0.2s;
}

nav a:hover {
  background-color: #333;
}

main {
  flex: 8;
}

.loader {
  width: 50px;
  height: 50px;
  border: 5px solid #f3f3f3;
  border-top: 5px solid #333; /* 로딩 바 색상 */
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

.btn {
  border-radius: 10px;
  padding: 10px;
  text-decoration: none;
}

.back-btn {
  background-color: red;
  color: white;
}

.return-btn {
  background-color: green;
  color: white;
}