/* ============================================
   星际玻璃 (Stellar Glass) 样式指南
   核心变量定义
============================================ */
:root {
  /* 色彩调色板 */
  --color-space: #0a0e17;
  --color-surface: rgba(16, 22, 36, 0.7);
  --color-primary: #00d4ff;
  --color-secondary: #9d4edd;
  --color-accent: #00ff9d;
  --color-text: #e0e0ff;
  --color-border: rgba(0, 212, 255, 0.3);
  --color-glow: rgba(0, 212, 255, 0.5);

  /* 字体 */
  --font-heading: 'Orbitron', sans-serif;
  --font-body: 'Exo 2', sans-serif;
  --font-mono: 'Rajdhani', sans-serif;

  /* 尺寸 */
  --radius-md: 12px;
  --radius-lg: 20px;
  --border-width: 1px;
  --blur-amount: 12px;

  /* 阴影 */
  --shadow-glow: 0 0 20px var(--color-glow);
  --shadow-card: 0 8px 32px rgba(0, 212, 255, 0.1);
  --shadow-hover: 0 12px 48px rgba(0, 212, 255, 0.2);

  /* 过渡 */
  --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================
   重置与基础样式
============================================ */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background-color: var(--color-space);
  color: var(--color-text);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
  line-height: 1.6;
}

/* 噪点纹理覆盖 */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: -1;
}

/* ============================================
   背景层：星空与行星
============================================ */
#starfield {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
}

.planet-container {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 80vmin;
  height: 80vmin;
  z-index: -1;
  opacity: 0.4;
  pointer-events: none;
}

.planet {
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 30% 30%, 
    var(--color-primary) 0%, 
    transparent 60%),
    radial-gradient(circle at 70% 70%, 
    var(--color-secondary) 0%, 
    transparent 60%);
  border-radius: 50%;
  animation: rotatePlanet 120s linear infinite;
  filter: blur(1px);
}

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

/* ============================================
   玻璃拟态通用类
============================================ */
.glass {
  background: var(--color-surface);
  backdrop-filter: blur(var(--blur-amount));
  -webkit-backdrop-filter: blur(var(--blur-amount));
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  transition: var(--transition-smooth);
}

.glass:hover {
  box-shadow: var(--shadow-hover);
  border-color: var(--color-primary);
}

/* ============================================
   头部导航栏
============================================ */
.glass-header {
  position: sticky;
  top: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  margin: 1rem;
  z-index: 1000;
  composes: glass;
}

.logo-container {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.site-title {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: 1px;
}

.digital-clock {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  color: var(--color-accent);
  padding: 0.5rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: rgba(0, 0, 0, 0.3);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.search-container {
  display: flex;
  align-items: center;
}

.search-input {
  font-family: var(--font-body);
  font-size: 1rem;
  padding: 0.75rem 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
  background: rgba(255, 255, 255, 0.05);
  color: var(--color-text);
  width: 300px;
  transition: var(--transition-smooth);
}

.search-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: var(--shadow-glow);
}

.search-btn {
  padding: 0.75rem 1.5rem;
  border: 1px solid var(--color-border);
  border-left: none;
  border-radius: 0 var(--radius-lg) var(--radius-lg) 0;
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  color: white;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.search-btn:hover {
  background: linear-gradient(135deg, var(--color-secondary), var(--color-primary));
  box-shadow: var(--shadow-glow);
}

.controls {
  display: flex;
  gap: 1rem;
}

.theme-toggle-btn {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.05);
  color: var(--color-primary);
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition-smooth);
}

.theme-toggle-btn:hover {
  background: var(--color-primary);
  color: var(--color-space);
  transform: rotate(15deg);
}

/* ============================================
   主内容区
============================================ */
main {
  max-width: 1400px;
  margin: 2rem auto;
  padding: 0 2rem;
}

.section-title {
  font-family: var(--font-heading);
  font-size: 2.2rem;
  margin: 3rem 0 2rem;
  padding-left: 1rem;
  border-left: 4px solid var(--color-primary);
  color: var(--color-text);
}

.grid-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 2rem;
}

/* ============================================
   链接卡片
============================================ */
.link-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-decoration: none;
  color: inherit;
  padding: 1.5rem;
  composes: glass;
  position: relative;
  overflow: hidden;
}

.link-item::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, var(--color-glow) 0%, transparent 70%);
  opacity: 0;
  transition: opacity 0.5s;
}

.link-item:hover::before {
  opacity: 0.3;
}

.planet-preview {
  width: 100px;
  height: 100px;
  margin-bottom: 1rem;
  position: relative;
}

.planet-icon {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  color: white;
  transition: var(--transition-smooth);
  animation: float 6s ease-in-out infinite;
}

.link-item:hover .planet-icon {
  transform: scale(1.1);
  box-shadow: 0 0 30px var(--color-glow);
}

.link-item span {
  font-family: var(--font-mono);
  font-size: 1.2rem;
  font-weight: 600;
  margin-top: 0.5rem;
  text-align: center;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* ============================================
   响应式设计
============================================ */
@media (max-width: 1024px) {
  .grid-container {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 1.5rem;
  }
  .search-input {
    width: 250px;
  }
}

@media (max-width: 768px) {
  .glass-header {
    flex-direction: column;
    gap: 1rem;
    padding: 1rem;
  }
  .header-controls {
    width: 100%;
    justify-content: space-between;
  }
  .search-input {
    width: 200px;
  }
  .section-title {
    font-size: 1.8rem;
  }
  .planet-preview {
    width: 80px;
    height: 80px;
  }
}

@media (max-width: 480px) {
  .grid-container {
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  }
  .search-input {
    width: 150px;
  }
}