/* 导航栏（独立样式） */
:root {
  --primary-dark: #1a1f3a;
  --gradient-start: #ff6b35;
  --gradient-end: #8b5cf6;
  --text-white: #ffffff;
}

.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: rgba(26, 31, 58, 0.95);
  backdrop-filter: blur(10px);
  z-index: 1000;
  transition: all 0.3s ease;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-icon {
  width: 280px;
  position: relative;
}

.logo {
  width: 200px;
  position: relative;
  margin-right: 10px;
}

.logo-text {
  color: var(--text-white);
  font-weight: 700;
  font-size: 24px;
  letter-spacing: 1px;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 30px;
  align-items: center;
}

.nav-tickets {
  color: var(--text-white);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: var(--text-white);
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
  white-space: nowrap;
}

.nav-link {
  color: var(--text-white);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
}

.nav-link:hover {
  color: var(--gradient-start);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  transition: width 0.3s ease;
}

.nav-link:hover::after {
  width: 100%;
}

/* 汉堡菜单（如后续启用） */
.hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
  gap: 4px;
}

.hamburger span {
  width: 25px;
  height: 3px;
  background: var(--text-white);
  transition: all 0.3s ease;
}

/* 移动端适配（<=768px） */
@media (max-width: 768px) {
  .nav-container {
    justify-content: space-between;
    flex-direction: row;
    height: auto;
    padding: 15px 20px;
    gap: 10px;
    align-items: center;
  }

  .nav-logo {
    justify-content: flex-start;
  }

  .nav-menu {
    display: flex;
    flex-direction: row;
    justify-content: flex-end;
    align-items: center;
    position: static;
    width: auto;
    height: auto;
    background: transparent;
    padding: 0;
    transition: none;
    gap: 15px;
  }

  .nav-menu.active {
    display: flex;
  }

  .hamburger {
    display: none;
  }

  .logo-icon {
    display: block;
    margin: 0;
  }
}

/* 超小屏（<=480px） */
@media (max-width: 480px) {
  .nav-container {
    padding: 12px 15px;
    gap: 8px;
  }

  .logo-icon {
    width: 160px;
  }

  .nav-menu {
    gap: 10px;
  }
}

/* === 统一购票按钮与菜单基础样式（作用域限定在 .navbar 内） === */
.navbar .nav-menu,
.navbar .nav-menu li {
  list-style: none;
  margin: 0;
  padding: 0;
}

.navbar .nav-menu a {
  color: #fff;
  text-decoration: none;
}

.navbar .nav-tickets,
.navbar a.nav-tickets,
.navbar .btn.nav-tickets {
  display: inline-block;
  padding: 6px 12px;
  font-size: 14px;
  line-height: 1.2;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: #fff !important;
  text-decoration: none !important;
  border: none;
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
  vertical-align: middle;
  white-space: nowrap;
}

.navbar .nav-tickets:hover,
.navbar a.nav-tickets:hover,
.navbar .btn.nav-tickets:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

.navbar .nav-tickets:focus-visible,
.navbar a.nav-tickets:focus-visible,
.navbar .btn.nav-tickets:focus-visible {
  outline: 2px solid rgba(255,255,255,0.8);
  outline-offset: 2px;
}

/* 避免页面私有 ul/a 通用规则影响间距 */
.navbar .nav-menu {
  gap: 30px;
  align-items: center;
}

/* 避免页面内对 img/ul/a 的全局规则影响 Logo 与菜单布局 */
.navbar .logo-icon {
  max-width: none;
  height: auto;
  width: 280px;
}

/* 统一“购票”按钮尺寸与对齐，避免被页面私有CSS覆盖 */
.navbar .nav-tickets,
.navbar a.nav-tickets,
.navbar .btn.nav-tickets {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 36px;
  padding: 8px 16px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  line-height: 1;
  cursor: pointer;
  text-decoration: none !important;
  color: #fff !important;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  border: none;
  box-shadow: 0 6px 18px rgba(0,0,0,0.15);
}

/* 悬浮态保持一致的上浮与阴影 */
.navbar .nav-tickets:hover,
.navbar a.nav-tickets:hover,
.navbar .btn.nav-tickets:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(0,0,0,0.18);
}

/* 对齐优化：菜单项垂直居中、间距统一 */
.navbar .nav-menu {
  align-items: center;
  gap: 30px;
}

/* === 统一导航栏“报名/购票”按钮在所有页面的样式 === */
.navbar .nav-menu .nav-tickets,
.navbar a.nav-tickets,
.navbar .btn.nav-tickets {
  display: inline-flex !important;
  align-items: center !important;
  justify-content: center !important;
  height: 36px !important;
  padding: 8px 16px !important;
  border-radius: 10px !important;
  font-size: 14px !important;
  font-weight: 600 !important;
  line-height: 1 !important;
  white-space: nowrap !important;
  min-width: auto !important;
  margin: 0 !important;
  box-sizing: border-box !important;

  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end)) !important;
  color: #fff !important;
  text-decoration: none !important;
  border: none !important;
  box-shadow: 0 6px 18px rgba(0,0,0,0.15) !important;
  cursor: pointer !important;
}

.navbar .nav-menu .nav-tickets:hover,
.navbar a.nav-tickets:hover,
.navbar .btn.nav-tickets:hover {
  transform: translateY(-2px) !important;
  box-shadow: 0 12px 28px rgba(0,0,0,0.18) !important;
}

/* 移动端保持一致 */
@media (max-width: 480px) {
  .navbar .nav-menu .nav-tickets,
  .navbar a.nav-tickets,
  .navbar .btn.nav-tickets {
    height: 36px !important;
    padding: 8px 16px !important;
    font-size: 14px !important;
    border-radius: 10px !important;
  }
}

/* === 统一全站“返回顶部”按钮样式（index/topic/speaker）=== */
.back-to-top {
  position: fixed !important;
  bottom: 24px !important;
  right: 24px !important;
  width: 48px !important;
  height: 48px !important;
  border: none !important;
  border-radius: 50% !important;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end)) !important;
  color: #fff !important;
  display: flex !important;
  align-items: center !important;
  justify-content: center !important;
  font-size: 18px !important;
  box-shadow: 0 12px 28px rgba(0,0,0,0.18) !important;
  cursor: pointer !important;
  z-index: 1000 !important;
  transition: opacity 0.25s ease, transform 0.25s ease, box-shadow 0.25s ease !important;
  opacity: 0 !important;
  visibility: hidden !important;
  pointer-events: none !important;
  transform: translateY(12px) !important;
}

.back-to-top:hover {
  background: var(--primary-dark) !important;
  box-shadow: 0 16px 36px rgba(0,0,0,0.22) !important;
  transform: translateY(0) !important;
}

/* 兼容不同页面脚本：.show 与 .visible 均显示 */
.back-to-top.show,
.back-to-top.visible {
  opacity: 1 !important;
  visibility: visible !important;
  pointer-events: auto !important;
  transform: translateY(0) !important;
}

/* 统一图标与文本箭头居中显示 */
.back-to-top svg {
  width: 24px !important;
  height: 24px !important;
  stroke: currentColor !important;
  fill: none !important;
}

.back-to-top:has(svg) {
  line-height: 0 !important;
}

.back-to-top:not(:has(svg)) {
  line-height: 1 !important; /* 文本箭头“↑”时居中 */
}

/* 移动端尺寸一致 */
@media (max-width: 480px) {
  .back-to-top {
    bottom: 20px !important;
    right: 20px !important;
    width: 44px !important;
    height: 44px !important;
    font-size: 16px !important;
    box-shadow: 0 10px 24px rgba(0,0,0,0.18) !important;
  }
  .back-to-top svg {
    width: 22px !important;
    height: 22px !important;
  }
}

/* === 移动端优化：Logo 最大占 50%，按钮完整显示 === */
@media (max-width: 768px) {
  .navbar .nav-logo {
    flex: 1 1 50%;
    max-width: 50%;
  }
  .navbar .logo-icon {
    width: 100%;
    height: auto;
  }
  .navbar .nav-menu {
    flex: 0 0 auto;
    flex-shrink: 0;
    gap: 10px;
  }
}

@media (max-width: 480px) {
  .navbar .nav-container {
    gap: 6px;
  }
  .navbar .nav-menu {
    gap: 8px;
  }
  .navbar .nav-tickets,
  .navbar a.nav-tickets,
  .navbar .btn.nav-tickets {
    padding: 8px 14px;
    font-size: 13px;
  }
}