/* ========================================
   GOM 游戏引擎网站 - 组件样式
   蓝白经典主题
   ======================================== */

/* ==========================================
   1. 按钮组件
   ========================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-xl);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-normal);
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}

/* 主要按钮 */
.btn--primary {
  background: var(--gradient-primary);
  color: var(--white);
  box-shadow: var(--glow-primary);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(66, 133, 244, 0.35);
}

.btn--primary:active {
  transform: translateY(0) scale(0.98);
}

/* 次要按钮 */
.btn--secondary {
  background: transparent;
  color: var(--text-primary);
  border: 2px solid var(--gray-300);
}

.btn--secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(66, 133, 244, 0.08);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(66, 133, 244, 0.15);
}

.btn--secondary:active {
  transform: translateY(0) scale(0.98);
}

/* 幽灵按钮 */
.btn--ghost {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--gray-300);
}

.btn--ghost:hover {
  background: rgba(66, 133, 244, 0.08);
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}

/* 金色按钮 */
.btn--accent {
  background: var(--gradient-accent);
  color: var(--white);
  box-shadow: 0 0 20px rgba(244, 162, 97, 0.4);
}

.btn--accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(244, 162, 97, 0.5);
}

/* 按钮尺寸 */
.btn--sm {
  padding: var(--space-sm) var(--space-md);
  font-size: var(--font-size-sm);
}

.btn--lg {
  padding: var(--space-lg) var(--space-2xl);
  font-size: var(--font-size-lg);
}

.btn--icon {
  width: 44px;
  height: 44px;
  padding: 0;
  border-radius: var(--radius-full);
}

/* ==========================================
   2. 卡片组件
   ========================================== */
.card {
  background: var(--white);
  border: 1px solid rgba(66, 133, 244, 0.1);
  border-radius: var(--radius-xl);
  padding: var(--space-xl);
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-card);
}

.card:hover {
  transform: translateY(-4px);
  border-color: var(--primary);
  box-shadow: var(--glow-primary);
}

.card--flat {
  background: var(--bg-secondary);
  box-shadow: none;
}

.card--bordered {
  background: transparent;
  border: 2px solid var(--primary);
  box-shadow: none;
}

.card--dark {
  background: var(--bg-secondary);
  border-color: rgba(255, 255, 255, 0.08);
  color: var(--text-primary);
}

.card--dark:hover {
  border-color: var(--primary);
}

/* 卡片图标 */
.card__icon {
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-primary);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-lg);
  font-size: var(--font-size-2xl);
  color: var(--white);
  box-shadow: var(--glow-primary);
}

.card__icon--accent {
  background: var(--gradient-accent);
  box-shadow: 0 0 20px rgba(244, 162, 97, 0.4);
}

.card__icon--blue {
  background: linear-gradient(135deg, #3B82F6 0%, #2563EB 100%);
  box-shadow: 0 0 20px rgba(59, 130, 246, 0.4);
}

.card__icon--dark {
  background: var(--bg-tertiary);
}

.card--dark .card__icon {
  color: var(--white);
}

/* 卡片标题 */
.card__title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-sm);
  color: var(--text-primary);
}

.card--dark .card__title {
  color: var(--text-primary);
}

/* 卡片描述 */
.card__desc {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  line-height: var(--line-height-relaxed);
}

.card--dark .card__desc {
  color: var(--text-secondary);
}

/* 卡片底部 */
.card__footer {
  margin-top: var(--space-lg);
  padding-top: var(--space-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.card--dark .card__footer {
  border-top-color: rgba(255, 255, 255, 0.08);
}

/* ==========================================
   3. 导航栏组件
   ========================================== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: var(--z-fixed);
  transition: all var(--transition-normal);
}

.header--transparent {
  background: rgba(32, 33, 36, 0.94);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.header--solid {
  background: var(--text-primary);
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.25);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.header--dark {
  background: var(--text-primary);
  border-bottom-color: rgba(255, 255, 255, 0.08);
}

/* 滚动放大效果 */
.header--scrolled {
  height: calc(var(--header-height) + 8px);
  background: rgba(32, 33, 36, 0.98);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.25);
}

.header--scrolled .header__container {
  transform: scale(1.02);
}

.header--scrolled .logo {
  transform: scale(1.05);
}

.header--scrolled .nav__list {
  transform: scale(1.02);
}

.header__container {
  max-width: var(--container-wide);
  margin: 0 auto;
  padding: 0 var(--space-xl);
  height: 100%;
  display: flex;
  align-items: center;
  transform-origin: center;
  will-change: transform;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  justify-content: space-between;
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--text-primary);
  text-decoration: none;
  will-change: transform;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.header .logo {
  color: var(--white);
}

.logo__image {
  /* height: 42px; */
  width: auto;
  object-fit: contain;
}

.logo--light {
  color: var(--text-primary);
}

/* 科技感Logo */
.logo--tech {
  position: relative;
  transition: all 0.3s ease;
}

.logo--tech:hover {
  transform: scale(1.02);
}

.logo__icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, #2563eb 0%, #06b6d4 50%, #3b82f6 100%);
  background-size: 200% 200%;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-xl);
  position: relative;
  overflow: hidden;
  box-shadow: 
    0 4px 15px rgba(37, 99, 235, 0.4),
    0 0 20px rgba(6, 182, 212, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
  animation: logo-gradient 4s ease infinite;
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.logo__icon svg {
  color: #fff;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
  position: relative;
  z-index: 2;
}

.logo__icon-glow {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 100%;
  height: 100%;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, rgba(6, 182, 212, 0.4) 0%, transparent 70%);
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: 1;
}

.logo--tech:hover .logo__icon-glow {
  opacity: 1;
}

.logo--tech:hover .logo__icon {
  box-shadow: 
    0 6px 25px rgba(37, 99, 235, 0.5),
    0 0 30px rgba(6, 182, 212, 0.4),
    inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

@keyframes logo-gradient {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.logo--light .logo__icon {
  background: var(--white);
}

.logo__text {
  display: flex;
  align-items: baseline;
  gap: 2px;
}

.logo__text-main {
  font-size: 1.25rem;
  font-weight: 800;
  background: linear-gradient(135deg, #ffffff 0%, #e0e7ff 50%, #ffffff 100%);
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: text-shine 3s linear infinite;
  letter-spacing: 1px;
  text-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
}

.logo__text-sub {
  font-size: 1.25rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.85);
  letter-spacing: 2px;
}

@keyframes text-shine {
  0% { background-position: 0% center; }
  100% { background-position: 200% center; }
}

.header .logo__text {
  color: var(--white);
  background: none;
  -webkit-text-fill-color: var(--white);
}

.logo--light .logo__text{
  color: var(--white);
  background: none;
  -webkit-text-fill-color: var(--white);
}

/* 导航菜单 */
.nav {
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 24px);
  height: 100%;
}

.nav__list {
  display: flex;
  align-items: center;
  gap: clamp(4px, 1.5vw, 16px);
  height: 100%;
  will-change: transform;
  transform-origin: center;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.nav__item {
  position: relative;
  height: 100%;
  display: flex;
  align-items: center;
}

.nav__item--has-submenu > .nav__link {
  padding-right: var(--space-sm);
}

.nav__caret {
  transition: transform var(--transition-fast);
}

.nav__submenu {
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 180px;
  padding: 8px;
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.12), 0 2px 8px rgba(0, 0, 0, 0.08);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity var(--transition-fast), visibility var(--transition-fast);
  z-index: var(--z-dropdown);
}

.nav__submenu::before {
  content: '';
  position: absolute;
  top: -8px;
  left: 0;
  right: 0;
  height: 8px;
}

.nav__submenu-item + .nav__submenu-item {
  margin-top: 2px;
}

.nav__submenu-link {
  display: block;
  padding: 10px 16px;
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  white-space: nowrap;
  transition: all var(--transition-fast);
  position: relative;
}

.nav__submenu-link:hover {
  color: var(--primary);
  background: rgba(66, 133, 244, 0.08);
}

.nav__item--has-submenu:hover .nav__submenu,
.nav__item--has-submenu:focus-within .nav__submenu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.nav__link {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm) clamp(8px, 1vw, 12px);
  color: var(--text-secondary);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  transition: all var(--transition-fast);
  border-radius: var(--radius-md);
  white-space: nowrap;
}

.header .nav__link {
  color: rgba(255, 255, 255, 0.85);
  background: transparent;
  padding: var(--space-sm) clamp(10px, 1.2vw, 16px);
}

.nav__link:hover,
.nav__link--active {
  color: var(--primary);
  background: rgba(66, 133, 244, 0.06);
}

.header .nav__link:hover,
.header .nav__link--active {
  color: var(--white);
  background: transparent;
}

.nav__link--active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 24px;
  height: 3px;
  background: #3b82f6;
  border-radius: var(--radius-full);
}

.header .nav__link--active::after {
  background: #3b82f6;
}

.nav--light .nav__link {
  color: rgba(255, 255, 255, 0.7);
}

.nav--light .nav__link:hover,
.nav--light .nav__link--active {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.1);
}

/* ========== 头部操作按钮区域 ========== */
.header__actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* ========== 用户菜单下拉 ========== */
.header__user {
  position: relative;
}

.header__user-trigger {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all 0.2s ease;
  color: var(--white);
}

.header__user-trigger:hover {
  background: rgba(255, 255, 255, 0.18);
  border-color: rgba(255, 255, 255, 0.35);
}

.header__user-trigger .icon {
  color: rgba(255, 255, 255, 0.9);
}

.header__user-name {
  font-size: 14px;
  font-weight: 500;
  max-width: 100px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.header__user-arrow {
  transition: transform 0.2s ease;
  opacity: 0.7;
}

.header__user:hover .header__user-arrow {
  transform: rotate(180deg);
}

.header__user-dropdown {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  min-width: 180px;
  background: var(--white);
  border-radius: var(--radius-lg);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15), 0 0 1px rgba(0, 0, 0, 0.1);
  padding: 8px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 1000;
}

.header__user-dropdown::before {
  content: '';
  position: absolute;
  top: -6px;
  right: 20px;
  width: 12px;
  height: 12px;
  background: var(--white);
  transform: rotate(45deg);
  border-radius: 2px;
}

.header__user:hover .header__user-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.header__user-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 500;
  border-radius: var(--radius-md);
  transition: all 0.15s ease;
  text-decoration: none;
}

.header__user-item .icon {
  color: var(--text-secondary);
  transition: color 0.15s ease;
}

.header__user-item:hover {
  background: var(--bg-secondary);
  color: var(--primary);
}

.header__user-item:hover .icon {
  color: var(--primary);
}

.header__user-divider {
  height: 1px;
  background: var(--border-light);
  margin: 6px 0;
}

.header__user-item--logout {
  color: var(--error);
}

.header__user-item--logout .icon {
  color: var(--error);
}

.header__user-item--logout:hover {
  background: rgba(234, 67, 53, 0.08);
  color: var(--error);
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
}

.menu-toggle__line {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: var(--radius-full);
  transition: all var(--transition-fast);
}

.header .menu-toggle__line {
  background: var(--white);
}

.header .btn--secondary {
  background: rgba(255, 255, 255, 0.08);
  color: var(--white);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.header .btn--secondary:hover {
  background: rgba(255, 255, 255, 0.16);
  border-color: rgba(255, 255, 255, 0.5);
  color: var(--white);
}

.menu-toggle--light .menu-toggle__line {
  background: var(--white);
}

.menu-toggle.active .menu-toggle__line:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active .menu-toggle__line:nth-child(2) {
  opacity: 0;
}

.menu-toggle.active .menu-toggle__line:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ==========================================
   4. 页脚组件
   ========================================== */
.footer {
  background: var(--bg-secondary);
  padding: var(--space-3xl) 0 var(--space-xl);
  margin-top: 0;
  color: var(--text-primary);
  border-top: 1px solid rgba(0, 180, 255, 0.1);
  flex-shrink: 0;
}

.footer--white {
  background: var(--text-primary);
  border-top: 1px solid rgba(0, 180, 255, 0.1);
  color: var(--text-primary);
}

.footer__top {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: var(--space-2xl);
  padding-bottom: var(--space-2xl);
  /*border-bottom: 1px solid rgba(255, 255, 255, 0.08);*/
}

.footer--white .footer__top {
  border-bottom-color: rgba(255, 255, 255, 0.08);
}

.footer__brand {
  max-width: 300px;
}

.footer__brand .logo {
  margin-bottom: var(--space-md);
}

/* Footer科技感Logo适配 */
.logo--footer .logo__text-main {
  background: linear-gradient(135deg, #2563eb 0%, #06b6d4 50%, #3b82f6 100%);
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.logo--footer .logo__text-sub {
  color: var(--text-secondary);
}

.footer__desc {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  line-height: var(--line-height-relaxed);
}

.footer--white .footer__desc {
  color: var(--text-secondary);
}

.footer__title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-lg);
  color: var(--text-primary);
}

.footer--white .footer__title {
  color: var(--text-primary);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer__link {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.footer--white .footer__link {
  color: var(--text-secondary);
}

.footer__link:hover {
  color: var(--primary);
  padding-left: var(--space-sm);
}

.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-lg);
  padding-bottom: var(--space-sm);
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

.footer__divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.08) 20%, rgba(255,255,255,0.08) 80%, transparent);
  margin-top: var(--space-xl);
}

.footer--white .footer__divider {
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.08) 20%, rgba(255,255,255,0.08) 80%, transparent);
}

.footer__copyright {
  line-height: 1.8;
  letter-spacing: 0.02em;
}

.footer--white .footer__bottom {
  color: var(--text-secondary);
}

.footer__social {
  display: flex;
  gap: var(--space-md);
}

.footer__social-link {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-full);
  color: var(--text-primary);
  transition: all var(--transition-fast);
}

.footer--white .footer__social-link {
  background: var(--bg-card);
  color: var(--text-primary);
}

.footer__social-link:hover {
  background: var(--primary);
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: var(--glow-primary);
}

/* ==========================================
   5. 输入框组件
   ========================================== */
.input {
  width: 100%;
  padding: var(--space-md) var(--space-lg);
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  color: var(--text-primary);
  font-size: var(--font-size-base);
  transition: all var(--transition-fast);
}

.input::placeholder {
  color: var(--text-secondary);
}

.input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(0, 180, 255, 0.2);
}

/* ==========================================
   6. 标签组件
   ========================================== */
.tag {
  display: inline-flex;
  align-items: center;
  padding: var(--space-xs) var(--space-md);
  background: rgba(66, 133, 244, 0.08);
  border: 1px solid var(--primary);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  color: var(--primary);
  font-weight: var(--font-weight-medium);
}

.tag--accent {
  background: rgba(244, 162, 97, 0.15);
  border-color: var(--accent);
  color: var(--accent);
}

.tag--success {
  background: rgba(16, 185, 129, 0.15);
  border-color: var(--success);
  color: var(--success);
}

/* ==========================================
   7. 徽章/角标
   ========================================== */
.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 20px;
  height: 20px;
  padding: 0 var(--space-xs);
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  color: var(--white);
}

.badge--dot {
  width: 8px;
  height: 8px;
  min-width: 8px;
  background: var(--success);
  animation: pulse 2s infinite;
}

/* ==========================================
   8. 分页组件
   ========================================== */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
}

.pagination__item {
  min-width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
  transition: all var(--transition-fast);
}

.pagination__item:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.pagination__item--active {
  background: var(--gradient-primary);
  border-color: var(--primary);
  color: var(--white);
  box-shadow: var(--glow-primary);
}

.pagination__item--disabled {
  opacity: 0.5;
  pointer-events: none;
}

/* ==========================================
   9. Tab 组件
   ========================================== */
.tabs {
  display: flex;
  gap: var(--space-sm);
  border-bottom: 2px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 0;
}

.tab {
  padding: var(--space-md) var(--space-xl);
  color: var(--text-secondary);
  font-weight: var(--font-weight-medium);
  border-radius: var(--radius-md) var(--radius-md) 0 0;
  transition: all var(--transition-fast);
  position: relative;
  background: none;
  border: none;
  cursor: pointer;
}

.tab:hover {
  color: var(--text-primary);
  background: var(--bg-card);
}

.tab--active {
  color: var(--primary);
  background: var(--bg-secondary);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: none;
}

.tab--active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--bg-secondary);
}

/* ==========================================
   10. 列表组件
   ========================================== */
.list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.list__item {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md);
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.list__item:hover {
  background: var(--bg-secondary);
  border-color: rgba(255, 255, 255, 0.1);
}

.list__icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(66, 133, 244, 0.08);
  border-radius: var(--radius-md);
  color: var(--primary);
}

.list__content {
  flex: 1;
}

.list__title {
  font-weight: var(--font-weight-medium);
  margin-bottom: var(--space-xs);
  color: var(--text-primary);
}

.list__desc {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

/* ==========================================
   11. 统计数字组件
   ========================================== */
.stat {
  text-align: center;
  padding: var(--space-xl);
}

.stat__number {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-weight-bold);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: var(--space-sm);
}

.stat__label {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* ==========================================
   12. 浮动元素
   ========================================== */
.back-to-top {
  position: fixed;
  bottom: var(--space-xl);
  right: var(--space-xl);
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-secondary);
  border: none;
  border-radius: var(--radius-full);
  color: var(--text-primary);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all var(--transition-normal);
  z-index: var(--z-sticky);
}

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

.back-to-top:hover {
  transform: translateY(-4px);
  background: var(--primary);
  box-shadow: var(--glow-primary);
}

/* ==========================================
   动画定义
   ========================================== */
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

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

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* 响应式 */
@media (max-width: 1200px) {
  .nav__link {
    font-size: var(--font-size-sm);
    padding: var(--space-xs) var(--space-sm);
  }
}

@media (max-width: 1024px) {
  .footer__top {
    grid-template-columns: repeat(2, 1fr);
  }

  .nav__list {
    gap: var(--space-xs);
  }

  .nav__link {
    font-size: var(--font-size-sm);
    padding: var(--space-xs) var(--space-sm);
  }
}

@media (max-width: 768px) {
  .nav__list {
    display: none;
  }

  .nav__submenu {
    display: none;
  }

  .menu-toggle {
    display: flex;
  }

  .footer__top {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .footer__brand {
    max-width: 100%;
  }

  .footer__bottom {
    flex-direction: column;
    gap: var(--space-md);
  }

  .btn--lg {
    padding: var(--space-md) var(--space-xl);
  }
}