/* ===== 02_每日大赛24小时挑战赛平台 - 全局样式 ===== */
:root {
  --primary: #FF7A00;
  --secondary: #13294B;
  --bg: #071629;
  --card: #10223F;
  --accent: #00D1FF;
  --text: #F7FBFF;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(0,0,0,0.12);
  --warning: #FF4D4D;
  --success: #00E676;
  --font-title: 'Impact', 'Arial Black', sans-serif;
  --font-mono: 'Courier New', monospace;
  --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.8;
  min-height: 100vh;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--primary);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ===== 布局容器 ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 60px 0;
}

/* ===== 导航栏 ===== */
.nav-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(7, 22, 41, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 122, 0, 0.2);
  padding: 12px 0;
}

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

.nav-logo {
  font-family: var(--font-title);
  font-size: 1.4rem;
  color: var(--primary);
  letter-spacing: 1px;
}

.nav-links {
  display: flex;
  gap: 24px;
  list-style: none;
}

.nav-links a {
  color: var(--text);
  font-size: 0.9rem;
  padding: 6px 12px;
  border-radius: 6px;
  transition: all 0.3s;
}

.nav-links a:hover {
  background: var(--card);
  color: var(--primary);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text);
  transition: 0.3s;
}

/* ===== Hero 挑战舱 ===== */
.hero-challenge {
  padding: 80px 0 60px;
  text-align: center;
  background: linear-gradient(180deg, rgba(255,122,0,0.08) 0%, transparent 60%);
  position: relative;
  overflow: hidden;
}

.hero-challenge::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at center, rgba(255,122,0,0.05) 0%, transparent 50%);
  animation: pulse-bg 8s ease-in-out infinite;
}

@keyframes pulse-bg {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}

.hero-title {
  font-family: var(--font-title);
  font-size: 2.8rem;
  color: var(--primary);
  margin-bottom: 12px;
  position: relative;
  z-index: 1;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text);
  opacity: 0.85;
  margin-bottom: 40px;
  position: relative;
  z-index: 1;
}

/* ===== 倒计时组件 ===== */
.countdown-panel {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin: 30px 0;
  position: relative;
  z-index: 1;
}

.countdown-item {
  background: var(--card);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  padding: 20px 24px;
  min-width: 90px;
  box-shadow: var(--shadow), 0 0 20px rgba(255,122,0,0.15);
}

.countdown-number {
  font-family: var(--font-mono);
  font-size: 2.4rem;
  font-weight: 900;
  color: var(--primary);
  display: block;
  line-height: 1;
}

.countdown-label {
  font-size: 0.75rem;
  color: var(--accent);
  margin-top: 6px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* ===== 阶段进度灯 ===== */
.phase-lights {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin: 30px 0;
  position: relative;
  z-index: 1;
}

.phase-light {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: rgba(247,251,255,0.6);
}

.phase-light.active {
  color: var(--primary);
}

.phase-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--secondary);
  border: 2px solid rgba(255,122,0,0.3);
}

.phase-light.active .phase-dot {
  background: var(--primary);
  border-color: var(--primary);
  box-shadow: 0 0 10px rgba(255,122,0,0.5);
  animation: dot-pulse 2s ease-in-out infinite;
}

@keyframes dot-pulse {
  0%, 100% { box-shadow: 0 0 10px rgba(255,122,0,0.5); }
  50% { box-shadow: 0 0 20px rgba(255,122,0,0.8); }
}

/* ===== 卡片系统 ===== */
.card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,209,255,0.1);
  transition: transform 0.3s, box-shadow 0.3s;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(0,0,0,0.2);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.card-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
}

.card-text {
  font-size: 0.95rem;
  line-height: 1.8;
  color: rgba(247,251,255,0.85);
}

/* ===== 挑战任务卡 ===== */
.challenge-task-card {
  background: linear-gradient(135deg, var(--card) 0%, rgba(255,122,0,0.05) 100%);
  border: 2px solid var(--primary);
  border-radius: var(--radius);
  padding: 32px;
  position: relative;
  overflow: hidden;
}

.challenge-task-card::after {
  content: '⚡';
  position: absolute;
  top: 16px;
  right: 20px;
  font-size: 2rem;
  opacity: 0.3;
}

.task-badge {
  display: inline-block;
  background: var(--primary);
  color: var(--bg);
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 700;
  margin-bottom: 16px;
}

/* ===== 进度条 ===== */
.progress-bar-wrap {
  background: var(--secondary);
  border-radius: 20px;
  height: 12px;
  overflow: hidden;
  margin: 16px 0;
}

.progress-bar-fill {
  height: 100%;
  border-radius: 20px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transition: width 1s ease;
}

/* ===== 截止提醒条 ===== */
.deadline-bar {
  padding: 12px 20px;
  border-radius: var(--radius);
  text-align: center;
  font-weight: 700;
  font-size: 0.9rem;
  transition: all 0.5s;
}

.deadline-bar.status-blue {
  background: rgba(0,209,255,0.15);
  border: 1px solid var(--accent);
  color: var(--accent);
}

.deadline-bar.status-orange {
  background: rgba(255,122,0,0.15);
  border: 1px solid var(--primary);
  color: var(--primary);
  animation: blink-soft 2s ease-in-out infinite;
}

.deadline-bar.status-red {
  background: rgba(255,77,77,0.15);
  border: 1px solid var(--warning);
  color: var(--warning);
  animation: blink-soft 1s ease-in-out infinite;
}

@keyframes blink-soft {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.7; }
}

/* ===== 投稿区 ===== */
.upload-zone {
  border: 2px dashed rgba(0,209,255,0.4);
  border-radius: var(--radius);
  padding: 40px;
  text-align: center;
  background: rgba(16,34,63,0.5);
  transition: all 0.3s;
  cursor: pointer;
}

.upload-zone:hover {
  border-color: var(--primary);
  background: rgba(255,122,0,0.05);
}

.upload-icon {
  font-size: 3rem;
  margin-bottom: 12px;
}

/* ===== 表格 ===== */
.data-table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
}

.data-table th,
.data-table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid rgba(0,209,255,0.1);
}

.data-table th {
  background: var(--card);
  color: var(--primary);
  font-weight: 700;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.data-table tr:hover td {
  background: rgba(255,122,0,0.03);
}

/* ===== FAQ ===== */
.faq-item {
  background: var(--card);
  border-radius: var(--radius);
  margin-bottom: 12px;
  border: 1px solid rgba(0,209,255,0.08);
  overflow: hidden;
}

.faq-question {
  padding: 18px 24px;
  font-weight: 700;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background 0.3s;
}

.faq-question:hover {
  background: rgba(255,122,0,0.05);
}

.faq-question::after {
  content: '▼';
  font-size: 0.7rem;
  color: var(--accent);
  transition: transform 0.3s;
}

.faq-item.open .faq-question::after {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 24px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.4s ease;
  color: rgba(247,251,255,0.8);
  line-height: 1.8;
}

.faq-item.open .faq-answer {
  padding: 0 24px 18px;
  max-height: 500px;
}

/* ===== 面包屑 ===== */
.breadcrumb {
  padding: 16px 0;
  font-size: 0.85rem;
  color: rgba(247,251,255,0.6);
}

.breadcrumb a {
  color: var(--accent);
}

.breadcrumb span {
  margin: 0 8px;
  color: rgba(247,251,255,0.3);
}

/* ===== 页脚 ===== */
.site-footer {
  background: var(--secondary);
  padding: 50px 0 30px;
  border-top: 2px solid var(--primary);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 30px;
  margin-bottom: 30px;
}

.footer-col h4 {
  color: var(--primary);
  font-size: 1rem;
  margin-bottom: 16px;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 8px;
}

.footer-col a {
  color: rgba(247,251,255,0.7);
  font-size: 0.9rem;
}

.footer-col a:hover {
  color: var(--primary);
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid rgba(255,122,0,0.2);
  font-size: 0.8rem;
  color: rgba(247,251,255,0.5);
}

/* ===== 按钮 ===== */
.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: 30px;
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  transition: all 0.3s;
  border: none;
  text-align: center;
}

.btn-primary {
  background: var(--primary);
  color: var(--bg);
}

.btn-primary:hover {
  background: #e86e00;
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(255,122,0,0.3);
  color: var(--bg);
}

.btn-accent {
  background: transparent;
  border: 2px solid var(--accent);
  color: var(--accent);
}

.btn-accent:hover {
  background: var(--accent);
  color: var(--bg);
}

/* ===== 标签 ===== */
.tag {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 0.75rem;
  background: rgba(0,209,255,0.1);
  color: var(--accent);
  margin: 2px 4px;
}

/* ===== 时间线 ===== */
.timeline {
  position: relative;
  padding-left: 30px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 8px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--primary), var(--accent));
}

.timeline-item {
  position: relative;
  margin-bottom: 24px;
  padding-left: 20px;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -26px;
  top: 8px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--primary);
  border: 2px solid var(--accent);
}

/* ===== 搜索框 ===== */
.search-box {
  display: flex;
  gap: 12px;
  max-width: 600px;
  margin: 0 auto;
}

.search-input {
  flex: 1;
  padding: 14px 20px;
  border-radius: 30px;
  border: 2px solid rgba(0,209,255,0.3);
  background: var(--card);
  color: var(--text);
  font-size: 1rem;
  outline: none;
  transition: border-color 0.3s;
}

.search-input:focus {
  border-color: var(--primary);
}

/* ===== 横向滑动 ===== */
.scroll-row {
  display: flex;
  gap: 20px;
  overflow-x: auto;
  padding: 10px 0 20px;
  scroll-snap-type: x mandatory;
}

.scroll-row::-webkit-scrollbar {
  height: 6px;
}

.scroll-row::-webkit-scrollbar-thumb {
  background: var(--primary);
  border-radius: 3px;
}

.scroll-card {
  min-width: 280px;
  scroll-snap-align: start;
  flex-shrink: 0;
}

/* ===== 统计数字 ===== */
.stats-row {
  display: flex;
  justify-content: center;
  gap: 40px;
  flex-wrap: wrap;
  margin: 30px 0;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 900;
  color: var(--primary);
}

.stat-label {
  font-size: 0.8rem;
  color: rgba(247,251,255,0.6);
  margin-top: 4px;
}

/* ===== 页面标题区 ===== */
.page-header {
  padding: 60px 0 30px;
  text-align: center;
  background: linear-gradient(180deg, rgba(255,122,0,0.06) 0%, transparent 100%);
}

.page-header h1 {
  font-family: var(--font-title);
  font-size: 2.2rem;
  color: var(--primary);
  margin-bottom: 12px;
}

.page-header p {
  font-size: 1rem;
  color: rgba(247,251,255,0.75);
  max-width: 700px;
  margin: 0 auto;
}

/* ===== 响应式断点 ===== */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background: var(--bg);
    flex-direction: column;
    padding: 20px;
    border-bottom: 2px solid var(--primary);
  }

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

  .nav-toggle {
    display: flex;
  }

  .hero-title {
    font-size: 1.8rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .countdown-panel {
    flex-wrap: wrap;
    gap: 10px;
  }

  .countdown-item {
    min-width: 70px;
    padding: 14px 16px;
  }

  .countdown-number {
    font-size: 1.8rem;
  }

  .phase-lights {
    flex-wrap: wrap;
    gap: 12px;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }

  .stats-row {
    gap: 20px;
  }

  .section {
    padding: 40px 0;
  }

  .page-header {
    padding: 40px 0 20px;
  }

  .page-header h1 {
    font-size: 1.6rem;
  }
}

@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .hero-title {
    font-size: 1.5rem;
  }

  .countdown-item {
    min-width: 60px;
    padding: 10px 12px;
  }

  .countdown-number {
    font-size: 1.4rem;
  }
}