* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
}

/* 真实的自然风景背景 */
body {
  min-height: 100vh;
  /* 这里用的是一张经典的湖泊雪山风景图 */
  background-image: url('https://images.unsplash.com/photo-1464822759023-fed622ff2c3b?q=80&w=2070&auto=format&fit=crop');
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  color: #1e293b;
  overflow-x: hidden;
}

/* 主界面居中 */
.hero {
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

/* 液态玻璃卡片 */
.glass-card {
  background: rgba(255, 255, 255, 0.4); /* 白色半透明 */
  backdrop-filter: blur(20px); /* 磨砂玻璃效果 */
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.6); /* 高光边缘 */
  border-radius: 24px;
  padding: 4rem 3rem;
  text-align: center;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
  max-width: 800px;
  width: 100%;
  animation: fadeIn 1s ease-out;
}

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

/* 标题文字 */
.glass-card h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  margin-bottom: 1rem;
  color: #0f172a; /* 深色文字配亮色背景 */
  font-weight: 800;
}

.subtitle {
  color: #475569;
  margin-bottom: 3rem;
  font-size: 1.1rem;
}

/* 链接按钮网格 */
.links-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1.2rem;
  justify-content: center;
}

.link-btn {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding: 0.8rem 1.8rem;
  border-radius: 12px;
  text-decoration: none;
  color: #0f172a;
  font-weight: 600;
  font-size: 1.05rem;
  transition: all 0.3s ease;
  background: rgba(255, 255, 255, 0.5); /* 半透明白 */
  border: 1px solid rgba(255, 255, 255, 0.8);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.link-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
  background: rgba(255, 255, 255, 0.8);
}

/* 各个平台的专属悬停颜色 (文字颜色微调) */
.link-btn.bilibili:hover { color: #fb7299; border-color: #fb7299; }
.link-btn.telegram-channel:hover { color: #0088cc; border-color: #0088cc; }
.link-btn.telegram-group:hover { color: #2aabee; border-color: #2aabee; }

.link-btn i { font-size: 1.4rem; }

/* ================= 侧边栏样式 ================= */
.menu-btn {
  position: fixed;
  top: 20px;
  left: 20px;
  z-index: 100;
  background: rgba(255, 255, 255, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.6);
  color: #0f172a;
  padding: 10px 16px;
  border-radius: 10px;
  cursor: pointer;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  font-size: 1rem;
  font-weight: 600;
  transition: all 0.3s;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.menu-btn:hover { background: rgba(255, 255, 255, 0.8); }

/* 侧边栏 (也是液态玻璃风格) */
.sidebar {
  position: fixed;
  top: 0;
  left: -350px;
  width: 320px;
  height: 100vh;
  background: rgba(255, 255, 255, 0.5);
  backdrop-filter: blur(25px);
  -webkit-backdrop-filter: blur(25px);
  border-right: 1px solid rgba(255, 255, 255, 0.6);
  z-index: 1000;
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  padding: 20px;
  box-shadow: 5px 0 30px rgba(0, 0, 0, 0.1);
}

.sidebar.active {
  transform: translateX(350px);
}

.sidebar-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.close-btn {
  background: none;
  border: none;
  color: #475569;
  font-size: 1.5rem;
  cursor: pointer;
  transition: color 0.3s;
}
.close-btn:hover { color: #0f172a; }

.project-list {
  list-style: none;
  flex: 1;
}

.project-list li { margin-bottom: 1rem; }

.project-list a {
  display: flex;
  align-items: center;
  gap: 15px;
  padding: 12px;
  text-decoration: none;
  color: #0f172a;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.5);
  transition: all 0.3s;
}

.project-list a:hover {
  background: rgba(255, 255, 255, 0.8);
  transform: translateX(5px);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.project-list i {
  font-size: 1.5rem;
  color: #3b82f6; /* 清爽的蓝色图标 */
  width: 30px;
  text-align: center;
}

.project-list h3 {
  font-size: 1rem;
  margin-bottom: 2px;
}

.project-list p {
  font-size: 0.8rem;
  color: #64748b;
}

.sidebar-footer {
  text-align: center;
  color: #64748b;
  font-size: 0.85rem;
  padding-top: 20px;
  border-top: 1px solid rgba(0, 0, 0, 0.05);
}

/* 遮罩层 */
.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.2); /* 淡淡的遮罩 */
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 500;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
}

.overlay.active {
  opacity: 1;
  visibility: visible;
}

/* 手机端适配 */
@media (max-width: 600px) {
  .glass-card { padding: 2.5rem 1.5rem; }
  .links-grid { flex-direction: column; }
  .link-btn { width: 100%; justify-content: center; }
  .sidebar { width: 280px; left: -280px; }
  .sidebar.active { transform: translateX(280px); }
}