/* ============================================================
   历史上的今天 — 专属样式
   ============================================================ */

/* ---------- 页面标题 ---------- */
.tih-hero {
  text-align: center;
  padding: clamp(48px, 8vw, 80px) var(--container-padding) clamp(24px, 4vw, 40px);
  position: relative;
}

.tih-hero-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto 20px;
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, #F59E0B, #D97706);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  color: #fff;
  box-shadow: 0 8px 30px rgba(245, 158, 11, 0.3);
  animation: fadeInScale 0.6s cubic-bezier(0.22, 0.61, 0.36, 1);
}

.tih-title {
  font-family: var(--font-display);
  font-size: var(--fs-hero);
  font-weight: 400;
  font-style: italic;
  color: var(--color-text);
  letter-spacing: -1px;
  margin-bottom: 8px;
  animation: fadeInUp 0.6s cubic-bezier(0.22, 0.61, 0.36, 1) 0.1s both;
}

.tih-date-display {
  font-size: var(--fs-body);
  color: var(--color-text-muted);
  letter-spacing: 0.5px;
  animation: fadeInUp 0.6s cubic-bezier(0.22, 0.61, 0.36, 1) 0.2s both;
}

.tih-date-num {
  color: #F59E0B;
  font-weight: 700;
  font-size: 1.1em;
}

/* ---------- 日期选择器 ---------- */
.tih-date-picker {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 0 var(--container-padding);
  margin-bottom: clamp(24px, 4vw, 40px);
  animation: fadeInUp 0.6s cubic-bezier(0.22, 0.61, 0.36, 1) 0.3s both;
}

.tih-date-input {
  padding: 10px 18px;
  border: 1.5px solid var(--color-border-strong);
  border-radius: var(--radius-full);
  background: var(--color-surface);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: border-color 0.2s, box-shadow 0.2s;
  outline: none;
  -webkit-appearance: none;
}

.tih-date-input:focus {
  border-color: #F59E0B;
  box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.15);
}

.tih-date-btn {
  padding: 10px 20px;
  border: none;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, #F59E0B, #D97706);
  color: #fff;
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 4px 15px rgba(245, 158, 11, 0.3);
}

.tih-date-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(245, 158, 11, 0.4);
}

.tih-date-btn:active {
  transform: scale(0.97);
}

/* ---------- 事件时间轴 ---------- */
.tih-timeline {
  max-width: 780px;
  margin: 0 auto;
  padding: 0 var(--container-padding) clamp(40px, 6vw, 80px);
  position: relative;
}

.tih-timeline::before {
  content: '';
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, transparent, var(--color-border-strong) 5%, var(--color-border-strong) 95%, transparent);
  transform: translateX(-50%);
}

/* ---------- 事件卡片 ---------- */
.tih-event {
  position: relative;
  display: flex;
  align-items: flex-start;
  margin-bottom: 32px;
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.5s ease-out, transform 0.5s ease-out;
}

.tih-event.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 奇数在左，偶数在右 */
.tih-event:nth-child(odd) {
  flex-direction: row;
  padding-right: calc(50% + 28px);
}

.tih-event:nth-child(even) {
  flex-direction: row-reverse;
  padding-left: calc(50% + 28px);
}

/* 时间轴圆点 */
.tih-event-dot {
  position: absolute;
  left: 50%;
  top: 18px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--color-surface);
  border: 3px solid #F59E0B;
  transform: translateX(-50%);
  z-index: 2;
  transition: background 0.3s, transform 0.3s;
}

.tih-event:hover .tih-event-dot {
  background: #F59E0B;
  transform: translateX(-50%) scale(1.3);
}

/* 卡片主体 */
.tih-event-card {
  flex: 1;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 20px 22px;
  border: 1.5px solid var(--color-border);
  box-shadow: 0 2px 12px var(--color-shadow);
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.35s, border-color 0.3s;
  cursor: default;
  position: relative;
  overflow: hidden;
}

.tih-event-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #F59E0B, #7C3AED);
  opacity: 0;
  transition: opacity 0.3s;
}

.tih-event:hover .tih-event-card {
  transform: translateY(-4px);
  box-shadow: 0 12px 36px var(--color-shadow-strong);
  border-color: rgba(245, 158, 11, 0.3);
}

.tih-event:hover .tih-event-card::before {
  opacity: 1;
}

/* 年份标签 */
.tih-event-year {
  display: inline-block;
  padding: 3px 12px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.12), rgba(124, 58, 237, 0.08));
  color: #D97706;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  margin-bottom: 10px;
  letter-spacing: 0.5px;
}

[data-theme="dark"] .tih-event-year {
  color: #FBBF24;
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.15), rgba(124, 58, 237, 0.1));
}

/* 事件描述 */
.tih-event-text {
  font-size: 0.92rem;
  color: var(--color-text);
  line-height: 1.7;
}

/* 分类标签 */
.tih-event-tag {
  display: inline-block;
  margin-top: 10px;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  --tag-opacity: 0.1;
}

[data-theme="dark"] .tih-event-tag { --tag-opacity: 0.15; }

.tih-event-tag.politics  { background: rgba(239, 68, 68, var(--tag-opacity)); color: #EF4444; }
.tih-event-tag.science   { background: rgba(59, 130, 246, var(--tag-opacity)); color: #3B82F6; }
.tih-event-tag.culture   { background: rgba(168, 85, 247, var(--tag-opacity)); color: #A855F7; }
.tih-event-tag.sports    { background: rgba(34, 197, 94, var(--tag-opacity)); color: #22C55E; }
.tih-event-tag.war       { background: rgba(239, 68, 68, var(--tag-opacity)); color: #DC2626; }
.tih-event-tag.tech      { background: rgba(6, 182, 212, var(--tag-opacity)); color: #0891B2; }
.tih-event-tag.people    { background: rgba(245, 158, 11, var(--tag-opacity)); color: #D97706; }

/* ---------- 底部返回按钮 ---------- */
.tih-back {
  text-align: center;
  padding: clamp(24px, 4vw, 48px) var(--container-padding) clamp(40px, 6vw, 80px);
}

.tih-back .btn-primary {
  background: linear-gradient(135deg, #F59E0B, #D97706);
  box-shadow: 0 4px 20px rgba(245, 158, 11, 0.35);
}

.tih-back .btn-primary:hover {
  box-shadow: 0 8px 30px rgba(245, 158, 11, 0.45);
}

/* ---------- 空状态 / 加载 ---------- */
.tih-empty,
.tih-loading {
  text-align: center;
  padding: clamp(40px, 8vw, 80px) var(--container-padding);
}

.tih-empty-icon {
  font-size: 3rem;
  color: var(--color-text-muted);
  margin-bottom: 16px;
}

.tih-empty-text {
  font-size: 0.95rem;
  color: var(--color-text-muted);
}

.tih-loading-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--color-border);
  border-top-color: #F59E0B;
  border-radius: 50%;
  margin: 0 auto 16px;
  animation: spin 0.8s linear infinite;
}

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

/* ---------- 更多事件按钮 ---------- */
.tih-more-btn {
  text-align: center;
  padding: 20px 0 10px;
}

.tih-more-btn-inner {
  padding: 10px 32px;
  border: 1.5px solid var(--color-border-strong);
  border-radius: var(--radius-full);
  background: var(--color-surface);
  color: var(--color-text-secondary);
  font-family: var(--font-body);
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s, background 0.2s, transform 0.2s;
}

.tih-more-btn-inner:hover {
  border-color: #F59E0B;
  color: #F59E0B;
  background: rgba(245, 158, 11, 0.05);
  transform: translateY(-2px);
}

/* ---------- 返回顶部按钮 ---------- */
.back-to-top {
  position: fixed;
  bottom: 130px;
  right: 32px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-surface);
  border: 1.5px solid var(--color-border);
  box-shadow: 0 4px 16px var(--color-shadow);
  color: var(--color-text-secondary);
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s, background 0.2s, color 0.2s;
  z-index: 999;
}

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

.back-to-top:hover {
  background: var(--color-primary-hex);
  color: #fff;
  border-color: var(--color-primary-hex);
}

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
  .tih-timeline::before {
    left: 20px;
  }

  .tih-event,
  .tih-event:nth-child(odd),
  .tih-event:nth-child(even) {
    flex-direction: row;
    padding-left: 48px;
    padding-right: 0;
  }

  .tih-event-dot {
    left: 20px;
  }

  .tih-date-picker {
    flex-direction: column;
    gap: 10px;
  }

  .tih-date-input,
  .tih-date-btn {
    width: 100%;
    max-width: 280px;
    text-align: center;
  }

  .tih-event-card {
    padding: 16px 18px;
  }
}

@media (max-width: 576px) {
  .tih-hero-icon {
    width: 56px;
    height: 56px;
    font-size: 1.6rem;
  }

  .tih-event-text {
    font-size: 0.85rem;
  }

  .tih-event-year {
    font-size: 0.75rem;
  }
}