/* 导航栏灵动岛设计 - 更现代的外观 */
[data-theme="dark"] .navbar {
  border-bottom-color: var(--nav-border);
  background: var(--nav-bg);
  backdrop-filter: blur(20px);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.6), inset 0 1px 0 rgba(255, 255, 255, 0.03);
}

[data-theme="dark"] .nav-item.active {
  background: linear-gradient(135deg, rgba(var(--accent-rgb), 0.25), rgba(var(--accent-rgb), 0.1));
  border-color: rgba(var(--accent-rgb), 0.5);
}

[data-theme="dark"] .nav-item:hover {
  background: linear-gradient(135deg, rgba(var(--accent-rgb), 0.15), rgba(var(--accent-rgb), 0.05));
}

/* ========== 灵动岛导航栏 - 现代设计 ========== */
.navbar {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%);
  width: fit-content;
  max-width: calc(100% - 40px);
  background: var(--nav-bg);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--nav-border);
  box-shadow: var(--shadow-nav), 0 6px 20px rgba(0,0,0,0.12);
  border-radius: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 24px;
  height: 60px;
  z-index: var(--z-nav);
  transition: all var(--transition-normal);
}

/* 当页面滚动或需要更强分隔时，可由 JS 添加 .scrolled */
.navbar.scrolled {
  box-shadow: 0 8px 30px rgba(0,0,0,0.15), 0 4px 12px rgba(0,0,0,0.08);
  backdrop-filter: blur(32px);
  border-color: rgba(0,0,0,0.08);
  top: 16px;
  height: 56px;
}

.nav-logo {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  padding: 0 16px;
  border-radius: 50px;
  transition: all var(--transition-fast);
}

.logo-text {
  color: var(--accent-color);
  font-weight: 700;
  font-size: 1.4rem;
  letter-spacing: -0.3px;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.logo-text:hover {
  color: var(--accent-light);
  transform: scale(1.05);
}

nav {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  min-height: 52px;
}

.nav-items {
  display: flex;
  align-items: center;
  justify-content: center;
  list-style: none;
  gap: 4px;
  padding: 0 16px;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}

.nav-item {
  color: var(--text-color);
  padding: 12px 20px;
  cursor: pointer;
  transition: all var(--transition-normal);
  font-weight: 500;
  text-decoration: none;
  border-radius: 50px;
  position: relative;
  background: transparent;
  border: 1px solid transparent;
  white-space: nowrap;
  display: flex;
  align-items: center;
  justify-content: center;
}

.nav-item:hover {
  color: var(--accent-color);
  background: rgba(180, 91, 99, 0.08);
  transform: translateY(-1px);
}

.nav-item.active {
  color: var(--accent-color);
  font-weight: 600;
  background: rgba(180, 91, 99, 0.1);
  border-color: rgba(180, 91, 99, 0.2);
  box-shadow: 0 4px 12px rgba(180, 91, 99, 0.1);
}

.nav-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-shrink: 0;
  padding: 0 16px;
  gap: 12px;
}

/* 主题切换开关 - 灵动岛风格 */
.theme-switch {
  position: relative;
  display: inline-flex;
  align-items: center;
  cursor: pointer;
  padding: 6px;
  border-radius: 50px;
  background: var(--surface-color);
  box-shadow: inset 0 1px 3px rgba(0,0,0,0.08), 0 2px 6px rgba(0,0,0,0.05);
}

.theme-switch input {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}

.slider {
  position: relative;
  display: inline-block;
  width: 52px;
  height: 28px;
  background-color: var(--border-color);
  border-radius: var(--radius-full);
  transition: background-color 0.3s var(--transition-bounce);
  cursor: pointer;
  box-shadow: inset 0 1px 2px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.05);
}

.slider:before {
  position: absolute;
  content: "";
  height: 22px;
  width: 22px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  transition: transform 0.3s var(--transition-bounce);
  border-radius: 50%;
  box-shadow: 0 2px 6px rgba(0,0,0,0.2);
}

.slider:after {
  position: absolute;
  content: "☀️";
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 13px;
  transition: opacity 0.2s;
  opacity: 0.7;
  pointer-events: none;
}

input:checked + .slider {
  background: linear-gradient(135deg, var(--accent-color), var(--accent-dark));
}

input:checked + .slider:before {
  transform: translateX(24px);
}

input:checked + .slider:after {
  content: "🌙";
  right: auto;
  left: 6px;
}

/* 移动端菜单按钮 - 灵动岛风格 */
.mobile-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 36px;
  height: 36px;
  cursor: pointer;
  border-radius: 50%;
  transition: all var(--transition-fast);
  background: var(--surface-color);
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
}

.mobile-toggle:hover {
  background: var(--accent-color);
  transform: scale(1.05);
}

.mobile-toggle:hover span {
  background: white;
}

.mobile-toggle span {
  width: 20px;
  height: 2px;
  background: var(--accent-color);
  margin: 3px 0;
  transition: all var(--transition-normal);
  border-radius: 2px;
}

/* ========== 标题替换功能 - 重叠布局（宽度不变） ========== */
/* 标题占位元素样式 - 绝对定位覆盖，不改变父容器宽度 */
.nav-title-placeholder {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-color);
  font-weight: 500;
  font-size: 1rem;
  white-space: nowrap;
  padding: 0 16px;
  border-radius: 50px;
  background: transparent;
  pointer-events: auto;
  z-index: 2;
  overflow: hidden;
}

/* 滚动文本容器 */
.nav-title-placeholder .title-scroll-container {
  display: inline-block;
  white-space: nowrap;
  will-change: transform;
}

/* 滚动动画 */
.nav-title-placeholder.scrolling .title-scroll-container {
  animation: scrollText linear infinite;
}

/* 鼠标悬浮时暂停滚动 */
.nav-title-placeholder.scrolling:hover .title-scroll-container {
  animation-play-state: paused;
}

@keyframes scrollText {
  0% {
    transform: translateX(0);
  }
  100% {
    transform: translateX(var(--scroll-distance, -50%));
  }
}

/* 标题模式下隐藏导航按钮（保持占位） */
.nav-items.title-mode-hidden {
  opacity: 0 !important;
  visibility: visible !important;
  pointer-events: none !important;
  transition: opacity 0.2s ease;
}

/* 禁用移动端标题替换功能（保持原有布局） */
@media (max-width: 768px) {
  :root {
    --nav-height: var(--nav-height-mobile);
  }

  .navbar {
    width: calc(100% - 40px);
    padding: 6px 16px;
    height: 52px;
    top: 12px;
  }

  .logo-text {
    font-size: 1.2rem;
  }

  .nav-items {
    display: flex;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    flex-direction: column;
    background: var(--nav-bg);
    backdrop-filter: blur(24px);
    padding: 20px 0;
    border-radius: 24px;
    box-shadow: var(--shadow-md);
    border-top: 1px solid var(--border-color);

    /* 动画相关 */
    opacity: 0;
    visibility: hidden;
    transform: translateY(-15px);
    transition: opacity 0.3s cubic-bezier(0.2, 0.9, 0.4, 1.1),
                visibility 0.3s cubic-bezier(0.2, 0.9, 0.4, 1.1),
                transform 0.3s cubic-bezier(0.2, 0.9, 0.4, 1.1);
    pointer-events: none;
  }

  .nav-items.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
  }

  .nav-item {
    margin: 4px 16px;
    padding: 12px 20px;
    text-align: center;
    width: auto;
  }

  .mobile-toggle {
    display: flex;
  }

  .mobile-toggle.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .mobile-toggle.active span:nth-child(2) {
    opacity: 0;
  }

  .mobile-toggle.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .nav-actions {
    min-width: auto;
  }

  /* 移动端禁用标题替换功能相关样式 */
  .nav-title-placeholder {
    display: none !important;
  }
  
  .nav-items.title-mode-hidden {
    opacity: 1 !important;
    pointer-events: auto !important;
  }
}

@media (max-width: 480px) {
  .navbar {
    width: calc(100% - 24px);
    padding: 6px 12px;
    height: 48px;
  }

  .logo-text {
    font-size: 1.1rem;
  }

  .slider {
    width: 44px;
    height: 24px;
  }

  .slider:before {
    width: 18px;
    height: 18px;
  }

  input:checked + .slider:before {
    transform: translateX(20px);
  }
  
  .nav-item {
    padding: 10px 16px;
    font-size: 0.9rem;
  }
}