:root {
  --primary-color: #333;
  --background-color: #fff;
  --card-color: #efebeb;
  --text-color: #333;
  --clock-bg-color: #1e272e;
  --clock-text-color: #0be881;
  --date-text-color: #a4b0be;
}

[data-theme="dark"] {
  --primary-color: #fff;
  --background-color: #333;
  --card-color: #302d2d;
  --text-color: #fff;
  --clock-bg-color: #1a1a1a;
  --date-text-color: #cccccc;
}

body {
  margin: 0;
  padding: 0;
  font-family: "Segoe UI", sans-serif;
  background-color: var(--background-color);
  color: var(--text-color);
}

header {
  background-color: var(--background-color);
  padding: 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo img {
  height: 50px;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 2rem;
}

nav a {
  color: var(--text-color);
  text-decoration: none;
  font-weight: bold;
}

.main {
  min-height: calc(100vh - 82px); /* header 높이를 고려하여 조정 */
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--background-color);
  transition: background-color 0.3s ease;
}

.clock-container {
  background: var(--clock-bg-color);
  padding: 40px;
  border-radius: 20px;
  box-shadow: 0 0 30px rgba(0, 0, 0, 0.4);
  color: var(--clock-text-color);
  transition: all 0.3s ease;
}

.clock {
  font-size: 80px;
  font-weight: 600;
  text-align: center;
  letter-spacing: 3px;
}

.date {
  font-size: 24px;
  text-align: center;
  letter-spacing: 2px;
  color: var(--date-text-color);
  margin-top: 10px;
  transition: color 0.3s ease;
}

.day {
  font-size: 20px;
  text-align: center;
  color: var(--date-text-color);
  margin-top: 5px;
  transition: color 0.3s ease;
}

.seconds {
  font-size: 40px;
  color: #05c46b;
}

.colon {
  animation: blink 1s infinite;
}

@keyframes blink {
  0% {
    opacity: 1;
  }
  50% {
    opacity: 0;
  }
  100% {
    opacity: 1;
  }
}

.meridiem {
  font-size: 30px;
  color: #05c46b;
}