/* ============================================
   应用布局 - 头部、侧边栏、内容区、响应式
   ============================================ */

/* ---- 整体布局 ---- */
.app-layout {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ---- 头部导航 ---- */
.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-xl);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border-light);
  backdrop-filter: blur(12px);
  background: rgba(255, 255, 255, 0.85);
}

[data-theme="dark"] .app-header {
  background: rgba(26, 26, 46, 0.85);
}

.header-left {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.header-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--text-xl);
  font-weight: var(--font-bold);
  color: var(--color-text);
  text-decoration: none;
}

.header-logo .logo-icon {
  width: 32px;
  height: 32px;
  background: var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 18px;
}

/* ---- 导航栏 ---- */
.nav-bar {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 8px 16px;
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--color-text-secondary);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  cursor: pointer;
  text-decoration: none;
  position: relative;
}

.nav-item:hover {
  color: var(--color-text);
  background: var(--color-bg-tertiary);
}

.nav-item.active {
  color: var(--color-primary);
  background: var(--color-primary-bg);
}

.nav-item.active::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 16px;
  right: 16px;
  height: 2px;
  background: var(--color-primary);
  border-radius: 1px;
}

/* ---- 头部右侧 ---- */
.header-right {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.theme-toggle {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  font-size: 18px;
  color: var(--color-text-secondary);
  transition: all var(--transition-fast);
  cursor: pointer;
  background: none;
  border: none;
}

.theme-toggle:hover {
  background: var(--color-bg-tertiary);
  color: var(--color-text);
}

/* ---- 主内容区 ---- */
.app-main {
  flex: 1;
  padding: var(--space-xl);
  max-width: var(--max-content-width);
  width: 100%;
  margin: 0 auto;
}

/* ---- 页面视图 ---- */
.page-view {
  display: none;
  animation: fadeInUp var(--transition-slow);
}

.page-view.active {
  display: block;
}

.page-title {
  font-size: var(--text-2xl);
  font-weight: var(--font-bold);
  color: var(--color-text);
  margin-bottom: var(--space-lg);
}

.page-subtitle {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  margin-top: calc(-1 * var(--space-md));
  margin-bottom: var(--space-lg);
}

/* ---- 网格布局 ---- */
.grid-stats {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: var(--space-md);
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-lg);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

/* ---- 移动端底部导航 ---- */
.mobile-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--color-surface);
  border-top: 1px solid var(--color-border-light);
  padding: var(--space-xs) 0;
  padding-bottom: env(safe-area-inset-bottom, 0px);
}

.mobile-nav-items {
  display: flex;
  justify-content: space-around;
}

.mobile-nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  padding: var(--space-sm) var(--space-md);
  min-height: 52px;
  font-size: var(--text-xs);
  color: var(--color-text-tertiary);
  cursor: pointer;
  transition: color var(--transition-fast);
  text-decoration: none;
}

.mobile-nav-item .nav-icon {
  font-size: 22px;
  line-height: 1;
}

.mobile-nav-item.active {
  color: var(--color-primary);
}

/* ---- 响应式 ---- */
@media (max-width: 1024px) {
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .app-header {
    padding: 0 var(--space-md);
  }

  .nav-bar {
    display: none;
  }

  .mobile-nav {
    display: block;
  }

  .app-main {
    padding: var(--space-md);
    padding-bottom: calc(80px + env(safe-area-inset-bottom, 0px));
  }

  .grid-2, .grid-3 {
    grid-template-columns: 1fr;
  }

  .grid-stats {
    grid-template-columns: repeat(2, 1fr);
  }

  .header-logo span {
    display: none;
  }
}

@media (max-width: 480px) {
  .grid-stats {
    grid-template-columns: 1fr;
  }
}