:root {
  --primary-color: #3498db;
  --secondary-color: #2c3e50;
  --accent-color: #e74c3c;
  --success-color: #2ecc71;
  --bg-color: #f5f5f5;
  --text-color: #333;
  --border-color: #ddd;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background: var(--bg-color);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.3s;
}

a:hover {
  color: var(--primary-color);
}

header {
  background: var(--secondary-color);
  color: #fff;
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.logo {
  font-size: 1.5rem;
  font-weight: bold;
}

.logo a {
  color: #fff;
}

nav ul {
  display: flex;
  flex-wrap: nowrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
}

nav li {
  flex: 1 1 0;
  min-width: 0;
}

nav a {
  display: block;
  padding: 0.5rem 1rem;
  color: #fff;
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  border-radius: 4px;
  transition: background 0.3s;
}

nav a:hover {
  background: rgba(255,255,255,0.1);
  color: #fff;
}

main {
  min-height: calc(100vh - 200px);
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.video-card {
  background: #fff;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

footer {
  background: var(--secondary-color);
  color: #fff;
  padding: 2rem 0;
  margin-top: 3rem;
  text-align: center;
}

@media (max-width: 767px) {
  .header-content {
    flex-direction: column;
    gap: 0.8rem;
  }

  nav ul {
    width: 100%;
    gap: 0.25rem;
  }

  nav a {
    padding: 0.4rem 0.25rem;
    font-size: 0.85rem;
  }

  .logo {
    font-size: 1.3rem;
  }

  h1 {
    font-size: 1.5rem !important;
  }

  .video-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  nav a {
    padding: 0.35rem 0.15rem;
    font-size: 0.75rem;
  }
}