/* 高级样式增强 */

.ui-style-0 { --primary: #c62828; --secondary: #f44336; }
.ui-style-1 { --primary: #ad1457; --secondary: #e91e63; }
.ui-style-2 { --primary: #6a1b9a; --secondary: #9c27b0; }
.ui-style-3 { --primary: #4527a0; --secondary: #673ab7; }
.ui-style-4 { --primary: #283593; --secondary: #3f51b5; }
.ui-style-5 { --primary: #1565c0; --secondary: #2196f3; }
.ui-style-6 { --primary: #0277bd; --secondary: #03a9f4; }
.ui-style-7 { --primary: #00838f; --secondary: #00bcd4; }
.ui-style-8 { --primary: #00695c; --secondary: #009688; }
.ui-style-9 { --primary: #2e7d32; --secondary: #4caf50; }
.ui-style-10 { --primary: #558b2f; --secondary: #8bc34a; }
.ui-style-11 { --primary: #9e9d24; --secondary: #cddc39; }
.ui-style-12 { --primary: #f9a825; --secondary: #ffeb3b; }
.ui-style-13 { --primary: #ff8f00; --secondary: #ffc107; }
.ui-style-14 { --primary: #ef6c00; --secondary: #ff9800; }
.ui-style-15 { --primary: #d84315; --secondary: #ff5722; }

body {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  background-attachment: fixed;
}

header {
  backdrop-filter: blur(10px);
  background: rgba(255, 255, 255, 0.95);
}

.logo {
  background: linear-gradient(135deg, var(--primary, #d32f2f), var(--secondary, #f44336));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 800;
  letter-spacing: 1px;
}

nav a {
  position: relative;
  font-weight: 500;
  transition: all 0.3s ease;
}

nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--primary, #d32f2f);
  transition: all 0.3s ease;
  transform: translateX(-50%);
}

nav a:hover::after {
  width: 80%;
}

main {
  animation: fadeIn 0.6s ease-in-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.intro,
section {
  animation: slideUp 0.6s ease-out;
  transition: all 0.3s ease;
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

h1 {
  background: linear-gradient(135deg, var(--primary, #d32f2f), var(--secondary, #f44336));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 800;
  text-align: center;
  margin-bottom: 30px;
  animation: titleFade 1s ease-in-out;
}

@keyframes titleFade {
  from { opacity: 0; transform: scale(0.9); }
  to { opacity: 1; transform: scale(1); }
}

h2 {
  position: relative;
  font-weight: 700;
}

h2::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  width: 4px;
  height: 60%;
  background: linear-gradient(180deg, var(--primary, #d32f2f), var(--secondary, #f44336));
  transform: translateY(-50%);
  border-radius: 2px;
}

.video-card {
  position: relative;
  overflow: hidden;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  border: 1px solid rgba(0,0,0,0.05);
}

.video-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.4), transparent);
  transition: left 0.5s;
}

.video-card:hover::before {
  left: 100%;
}

.video-card:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: 0 12px 24px rgba(0,0,0,0.2);
  border-color: var(--primary, #d32f2f);
}

.video-title {
  position: relative;
  transition: color 0.3s;
}

.video-card:hover .video-title {
  color: var(--primary, #d32f2f);
}

.video-link {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--primary, #d32f2f), var(--secondary, #f44336));
  box-shadow: 0 4px 12px rgba(211, 47, 47, 0.3);
}

.video-link::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255,255,255,0.3);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}

.video-link:hover::before {
  width: 300px;
  height: 300px;
}

.video-link:active {
  transform: scale(0.95);
}

footer {
  background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
  position: relative;
  overflow: hidden;
}

footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.5), transparent);
}

@media (max-width: 768px) {
  nav a {
    font-size: 13px;
    padding: 8px 4px;
  }

  nav a::after {
    display: none;
  }

  .video-card:hover {
    transform: translateY(-4px) scale(1.01);
  }
}

.intro p {
  text-align: justify;
  color: #555;
  font-size: 15px;
}

article section {
  margin-bottom: 25px;
}

article h2 {
  font-size: 20px;
  margin-bottom: 15px;
}

article p {
  text-indent: 2em;
}

article p strong {
  color: var(--primary, #d32f2f);
  font-weight: 600;
}

section:hover {
  box-shadow: 0 4px 16px rgba(0,0,0,0.1);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}