/* ==========================================================================
   现代化增强样式 - 添加到现有style.css
   ========================================================================== */

/* CSS变量系统 - 统一红色色调主题 */
:root {
  --primary-color: #e80000;        /* 主红色 */
  --primary-hover: #cc0000;        /* 深红色 - 悬停 */
  --primary-light: rgba(232, 0, 0, 0.1);
  --secondary-color: #ff4444;      /* 浅红色 - 次要元素 */
  --secondary-hover: #ff3333;      /* 深一点的红 - 悬停 */
  --success-color: #28a745;        /* 保持绿色用于成功状态 */
  --warning-color: #ffc107;        /* 保持黄色用于警告 */
  --error-color: #dc3545;          /* 保持深红用于错误 */
  
  /* 中性色 */
  --text-primary: #2b2929;
  --text-secondary: #666;
  --text-muted: #999;
  --border-light: #eee;
  --border-medium: #ddd;
  --bg-white: #fff;
  --bg-light: #f6f8fb;
  --bg-section: #f8f9fa;
  
  /* 字体 */
  --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --font-family-mono: "Microsoft Yahei", monospace;
  --font-size-xs: 12px;
  --font-size-sm: 13px;
  --font-size-base: 14px;
  --font-size-lg: 16px;
  --font-size-xl: 18px;
  --font-size-2xl: 20px;
  --font-size-3xl: 24px;
  
  /* 间距 */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-2xl: 48px;
  
  /* 阴影 */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
  --shadow-md: 0 3px 6px rgba(0, 0, 0, 0.16), 0 3px 6px rgba(0, 0, 0, 0.23);
  --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.19), 0 6px 6px rgba(0, 0, 0, 0.23);
  
  /* 边框半径 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  
  /* 过渡 */
  --transition-fast: 0.15s ease-in-out;
  --transition-base: 0.3s ease-out;
  --transition-slow: 0.5s ease-out;
  
  /* 断点 */
  --breakpoint-sm: 480px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 992px;
  --breakpoint-xl: 1200px;
}

/* ==========================================================================
   增强的导航样式
   ========================================================================== */

/* 导航栏滚动效果 */
.hua-navbar.scrolled {
  background: rgba(255, 255, 255, 0.95) !important;
  backdrop-filter: blur(10px) !important;
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.15) !important;
  transition: all var(--transition-base) !important;
}

/* 导航链接增强 */
.nav-list > li > a {
  position: relative;
  transition: all var(--transition-base) !important;
}

.nav-list > li > a::after {
  content: '';
  position: absolute;
  bottom: 20px;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--primary-color);
  transition: all var(--transition-base);
  transform: translateX(-50%);
}

.nav-list > li > a:hover::after,
.nav-list > li.current > a::after {
  width: 80%;
}

/* 下拉菜单增强 */
.dropdown-menu {
  background: var(--bg-white) !important;
  border: 1px solid var(--border-light) !important;
  border-radius: var(--radius-md) !important;
  box-shadow: var(--shadow-lg) !important;
  transition: all var(--transition-base) !important;
  opacity: 0 !important;
  visibility: hidden !important;
  transform: translateY(10px) !important;
}

.nav-item:hover .dropdown-menu {
  opacity: 1 !important;
  visibility: visible !important;
  transform: translateY(0) !important;
}

.sub-nav li a {
  transition: all var(--transition-fast) !important;
}

.sub-nav li a:hover {
  background: var(--bg-section) !important;
  color: var(--primary-color) !important;
  padding-left: 25px !important;
}

/* ==========================================================================
   搜索框增强
   ========================================================================== */

.search-container {
  position: relative;
}

.search-toggle {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: var(--spacing-sm);
  border-radius: var(--radius-md);
  transition: var(--transition-fast);
}

.search-toggle:hover {
  color: var(--primary-color);
}

.search-toggle:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

.search-form-wrapper {
  position: absolute;
  top: 100%;
  right: 0;
  width: 300px;
  background: var(--bg-white);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all var(--transition-base);
  z-index: 1000;
  padding: var(--spacing-lg);
  margin-top: var(--spacing-sm);
}

.search-container:hover .search-form-wrapper,
.search-container.active .search-form-wrapper {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.search-input {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  outline: none;
  transition: border-color var(--transition-fast);
}

.search-input:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 2px rgba(232, 0, 0, 0.2);
}

.search-submit {
  background: var(--primary-color);
  border: none;
  border-radius: var(--radius-md);
  color: white;
  cursor: pointer;
  padding: var(--spacing-sm) var(--spacing-md);
  transition: background-color var(--transition-fast);
  margin-left: var(--spacing-sm);
}

.search-submit:hover {
  background: var(--primary-hover);
}

/* ==========================================================================
   移动端菜单增强
   ========================================================================== */

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
  position: relative;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  transition: var(--transition-fast);
}

.mobile-menu-toggle:hover {
  background: var(--bg-section);
}

.mobile-menu-toggle:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

.menu-icon {
  display: block;
  position: relative;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: all var(--transition-base);
}

.menu-icon::before,
.menu-icon::after {
  content: '';
  position: absolute;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  left: 0;
  transition: all var(--transition-base);
}

.menu-icon::before {
  top: -8px;
}

.menu-icon::after {
  top: 8px;
}

.mobile-menu-toggle.active .menu-icon {
  background: transparent;
}

.mobile-menu-toggle.active .menu-icon::before {
  transform: rotate(45deg);
  top: 0;
}

.mobile-menu-toggle.active .menu-icon::after {
  transform: rotate(-45deg);
  top: 0;
}

/* ==========================================================================
   文章列表增强
   ========================================================================== */

.article-item {
  transition: all var(--transition-base) !important;
  border-radius: var(--radius-sm) !important;
}

.article-item:hover {
  background: var(--primary-light) !important;
  margin: 0 -10px !important;
  padding: 12px 10px !important;
  box-shadow: var(--shadow-sm) !important;
}

.article-item a {
  transition: var(--transition-fast) !important;
}

.article-item a:hover .article-title {
  color: var(--primary-color) !important;
}

/* ==========================================================================
   侧边栏增强
   ========================================================================== */

.sidebar-section {
  transition: var(--transition-base) !important;
}

.sidebar-section:hover {
  box-shadow: var(--shadow-md) !important;
  transform: translateY(-2px);
}

.rank-item {
  transition: var(--transition-base) !important;
}

.rank-item:hover {
  background: var(--bg-section) !important;
  margin: 0 -10px !important;
  padding: 12px 10px !important;
  border-radius: var(--radius-sm) !important;
}

.rank-content a {
  transition: var(--transition-fast) !important;
}

.rank-content a:hover {
  color: var(--primary-color) !important;
}

/* ==========================================================================
   返回顶部按钮增强
   ========================================================================== */

.rollbar {
  position: fixed;
  right: 20px;
  bottom: 30%;
  z-index: 99;
  display: block;
}

#go-to-top {
  transition: all var(--transition-base) !important;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
}

#go-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

#go-to-top:hover {
  background: var(--primary-color) !important;
  color: white !important;
  transform: translateY(-2px) !important;
  box-shadow: var(--shadow-lg) !important;
}

/* ==========================================================================
   加载动画
   ========================================================================== */

.loading {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.loaded {
  opacity: 1;
  transform: translateY(0);
}

/* 渐入动画 */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

/* ==========================================================================
   响应式增强
   ========================================================================== */

@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: block;
  }
  
  .main-nav {
    position: fixed;
    top: 80px;
    left: 0;
    right: 0;
    background: var(--bg-white);
    border-top: 1px solid var(--border-light);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-20px);
    transition: all var(--transition-base);
    max-height: calc(100vh - 80px);
    overflow-y: auto;
    z-index: 999;
  }
  
  .main-nav.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
  
  .nav-list {
    flex-direction: column;
    gap: 0;
    padding: var(--spacing-lg);
  }
  
  .nav-list > li {
    width: 100%;
    margin-bottom: var(--spacing-sm);
  }
  
  .nav-list > li > a {
    display: block;
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--border-light);
  }
  
  .dropdown-menu {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    padding: var(--spacing-sm);
    background: var(--bg-section);
    border-radius: var(--radius-sm);
    margin-top: var(--spacing-xs);
    display: none;
  }
  
  .nav-item:hover .dropdown-menu,
  .nav-item.active .dropdown-menu {
    display: block;
  }
  
  .search-form-wrapper {
    position: fixed;
    top: 80px;
    left: var(--spacing-sm);
    right: var(--spacing-sm);
    width: auto;
    max-width: none;
    z-index: 1000;
  }
}

@media (max-width: 480px) {
  .hua-navbar {
    height: 60px !important;
  }
  
  .main-nav {
    top: 60px;
    max-height: calc(100vh - 60px);
  }
  
  .search-form-wrapper {
    top: 60px;
  }
  
  .nav-list > li > a {
    padding: var(--spacing-sm) 0;
    font-size: var(--font-size-sm);
  }
  
  .rollbar {
    right: var(--spacing-sm);
    bottom: var(--spacing-sm);
  }
}

/* ==========================================================================
   无障碍增强
   ========================================================================== */

/* 焦点可见性 */
.nav-link:focus,
.search-input:focus,
.search-submit:focus,
.mobile-menu-toggle:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* 减少动画的用户偏好 */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* 高对比度模式支持 */
@media (prefers-contrast: high) {
  :root {
    --border-light: #000;
    --border-medium: #000;
    --text-secondary: #000;
    --text-muted: #333;
  }
}

/* ==========================================================================
   性能优化
   ========================================================================== */

/* GPU加速 */
.nav-list > li > a,
.search-toggle,
.mobile-menu-toggle,
.article-item,
.rank-item,
.sidebar-section {
  will-change: transform;
}

/* 避免重绘 */
.list-image:hover img,
.item-img:hover img {
  transform: scale(1.03);
  transition: transform 0.3s ease-out;
}

/* ==========================================================================
   打印样式
   ========================================================================== */

@media print {
  .mobile-menu-toggle,
  .search-container,
  .rollbar,
  .hua-navbar {
    display: none !important;
  }
  
  .main-nav {
    display: none !important;
  }
  
  .article-item,
  .sidebar-section {
    box-shadow: none !important;
    border: 1px solid #ccc !important;
  }
  
  a {
    color: #000 !important;
    text-decoration: underline !important;
  }
}