/* ============================================
   防震小卫士 — 通用样式表
   暗色主题 · 霓虹科技感 · 响应式
   ============================================ */

/* --- CSS 自定义属性（主题色） --- */
:root {
  --color-bg-start: #0b0e1a;
  --color-bg-end: #1a1040;
  --color-primary: #00d4ff;
  --color-secondary: #ff6b35;
  --color-accent: #a855f7;
  --color-text: #e0e0ff;
  --color-text-muted: #9898c0;
  --color-card-bg: rgba(255, 255, 255, 0.06);
  --color-card-border: rgba(255, 255, 255, 0.1);
  --color-shadow: rgba(0, 212, 255, 0.15);
  --radius: 16px;
  --radius-sm: 10px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- 全局重置 --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Microsoft YaHei", "Helvetica Neue", sans-serif;
  background:
    radial-gradient(ellipse at 15% 40%, rgba(0, 212, 255, 0.15) 0%, transparent 45%),
    radial-gradient(ellipse at 85% 25%, rgba(168, 85, 247, 0.18) 0%, transparent 45%),
    radial-gradient(ellipse at 50% 75%, rgba(255, 107, 53, 0.12) 0%, transparent 45%),
    radial-gradient(ellipse at 50% 50%, rgba(0, 212, 255, 0.04) 0%, transparent 70%),
    linear-gradient(135deg, var(--color-bg-start), var(--color-bg-end));
  color: var(--color-text);
  min-height: 100vh;
  line-height: 1.6;
  padding: 20px;
  position: relative;
  animation: bgBreath 8s ease-in-out infinite alternate;
}

@keyframes bgBreath {
  0%   { background-size: 100% 100%; }
  50%  { background-size: 110% 110%; background-position: 0% 0%; }
  100% { background-size: 100% 100%; background-position: 0% 0%; }
}

/* 星光粒子背景 — 动态星云效果 + 流星划过 */
body::before {
  content: '';
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image:
    /* 大星星（带光晕）— 更亮 */
    radial-gradient(3px 3px at 8% 15%, rgba(255,255,255,1) 0%, transparent 100%),
    radial-gradient(2.5px 2.5px at 22% 72%, rgba(255,255,255,0.95) 0%, transparent 100%),
    radial-gradient(3.5px 3.5px at 48% 8%, rgba(255,255,255,1) 0%, transparent 100%),
    radial-gradient(2.5px 2.5px at 68% 55%, rgba(255,255,255,0.9) 0%, transparent 100%),
    radial-gradient(3px 3px at 88% 82%, rgba(255,255,255,1) 0%, transparent 100%),
    radial-gradient(2.5px 2.5px at 35% 92%, rgba(255,255,255,0.9) 0%, transparent 100%),
    radial-gradient(3.5px 3.5px at 75% 18%, rgba(255,255,255,1) 0%, transparent 100%),
    radial-gradient(2.5px 2.5px at 55% 42%, rgba(255,255,255,0.9) 0%, transparent 100%),
    /* 彩色星星 — 更亮 */
    radial-gradient(2.5px 2.5px at 12% 45%, rgba(0, 212, 255, 0.95) 0%, transparent 100%),
    radial-gradient(3px 3px at 60% 70%, rgba(168, 85, 247, 0.9) 0%, transparent 100%),
    radial-gradient(2.5px 2.5px at 92% 35%, rgba(255, 107, 53, 0.85) 0%, transparent 100%),
    radial-gradient(2.5px 2.5px at 40% 30%, rgba(0, 212, 255, 0.8) 0%, transparent 100%),
    radial-gradient(3px 3px at 78% 90%, rgba(168, 85, 247, 0.85) 0%, transparent 100%),
    /* 小星星（密集）— 更亮 */
    radial-gradient(1.5px 1.5px at 5% 25%, rgba(255,255,255,0.8) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 18% 50%, rgba(255,255,255,0.7) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 28% 10%, rgba(255,255,255,0.75) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 42% 65%, rgba(255,255,255,0.65) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 58% 22%, rgba(255,255,255,0.7) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 72% 45%, rgba(255,255,255,0.65) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 82% 5%, rgba(255,255,255,0.75) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 95% 60%, rgba(255,255,255,0.7) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 15% 85%, rgba(255,255,255,0.65) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 50% 50%, rgba(255,255,255,0.6) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 65% 5%, rgba(255,255,255,0.7) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 33% 78%, rgba(255,255,255,0.65) 0%, transparent 100%),
    radial-gradient(1.5px 1.5px at 90% 48%, rgba(255,255,255,0.6) 0%, transparent 100%);
  background-size: 100% 100%;
  pointer-events: none;
  z-index: 0;
  animation: twinkle 1.5s ease-in-out infinite alternate, starDrift 8s linear infinite;
}

@keyframes twinkle {
  0%   { opacity: 0.2; }
  40%  { opacity: 1; }
  70%  { opacity: 0.6; }
  100% { opacity: 0.3; }
}

/* 星星漂移 — 像在太空中流动，幅度更大 */
@keyframes starDrift {
  0%   { background-position: 0% 0%; }
  20%  { background-position: 4% 6%; }
  40%  { background-position: -3% 10%; }
  60%  { background-position: 5% 4%; }
  80%  { background-position: -2% 8%; }
  100% { background-position: 0% 0%; }
}

/* 流星划过效果 — 更频繁 */
body::after {
  content: '';
  position: fixed;
  top: -100px;
  left: -100px;
  width: 200px;
  height: 2px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.9), transparent);
  border-radius: 50%;
  filter: blur(1px);
  pointer-events: none;
  z-index: 1;
  animation: meteor 3s ease-in-out infinite;
}

@keyframes meteor {
  0%   { transform: translate(0, 0) rotate(-30deg); opacity: 0; }
  4%   { opacity: 1; }
  12%  { transform: translate(500px, 350px) rotate(-30deg); opacity: 0; }
  100% { transform: translate(500px, 350px) rotate(-30deg); opacity: 0; }
}

/* --- 渐变标题 --- */
.gradient-title {
  font-size: 2.2rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 0.5rem;
}

/* --- 导航栏 --- */
.nav-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
  margin-bottom: 32px;
  padding: 12px 0;
}

.nav-bar a {
  color: var(--color-text-muted);
  text-decoration: none;
  padding: 8px 18px;
  border-radius: var(--radius-sm);
  background: var(--color-card-bg);
  border: 1px solid var(--color-card-border);
  font-size: 0.95rem;
  transition: var(--transition);
}

.nav-bar a:hover {
  color: var(--color-primary);
  border-color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 20px var(--color-shadow);
}

.nav-bar a.active {
  color: var(--color-primary);
  border-color: var(--color-primary);
  background: rgba(0, 212, 255, 0.1);
}

/* --- 卡片网格 --- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  max-width: 1100px;
  margin: 0 auto;
}

.card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
  padding: 28px 22px;
  text-align: center;
  backdrop-filter: blur(4px);
  transition: var(--transition);
  cursor: default;
}

.card:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: 0 8px 30px var(--color-shadow);
  border-color: var(--color-primary);
}

.card .icon {
  font-size: 3rem;
  display: block;
  margin-bottom: 12px;
}

.card h3 {
  font-size: 1.3rem;
  margin-bottom: 8px;
  color: var(--color-primary);
}

.card p {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  margin-bottom: 16px;
}

/* --- 卡片插图（首页） --- */
.card-illust {
  padding-top: 0;
  overflow: hidden;
}

.card-illust-bg {
  position: relative;
  height: 120px;
  margin: 0 -22px 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.card-illust-icon {
  font-size: 3.2rem;
  z-index: 2;
  filter: drop-shadow(0 0 12px rgba(0, 212, 255, 0.4));
  animation: illustFloat 3s ease-in-out infinite;
}

@keyframes illustFloat {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-6px); }
}

/* 知识卡片 — 书本小点阵 */
.card-knowledge .card-illust-bg {
  background: linear-gradient(135deg, rgba(0, 212, 255, 0.12), rgba(168, 85, 247, 0.08));
}
.card-illust-dots {
  position: absolute;
  width: 80px; height: 80px;
  background-image: radial-gradient(circle, var(--color-primary) 1.5px, transparent 1.5px);
  background-size: 12px 12px;
  opacity: 0.25;
  right: 10px; bottom: 5px;
  border-radius: 8px;
}

/* 模拟器卡片 — 波浪线 */
.card-simulator .card-illust-bg {
  background: linear-gradient(135deg, rgba(255, 107, 53, 0.12), rgba(0, 212, 255, 0.08));
}
.card-illust-waves {
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 30px;
  background: repeating-linear-gradient(
    -45deg,
    transparent,
    transparent 6px,
    rgba(0, 212, 255, 0.15) 6px,
    rgba(0, 212, 255, 0.15) 12px
  );
}

/* 清单卡片 — 对勾装饰 */
.card-checklist .card-illust-bg {
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.12), rgba(0, 212, 255, 0.08));
}
.card-illust-check {
  position: absolute;
  width: 50px; height: 50px;
  right: 15px; bottom: 10px;
  opacity: 0.15;
  font-size: 2.5rem;
}
.card-illust-check::after {
  content: '✓✓';
  color: var(--color-primary);
}

/* 故事卡片 — 翻页效果 */
.card-story .card-illust-bg {
  background: linear-gradient(135deg, rgba(0, 212, 255, 0.12), rgba(255, 107, 53, 0.08));
}
.card-illust-pages {
  position: absolute;
  width: 40px; height: 50px;
  right: 18px; bottom: 8px;
  border: 2px solid rgba(0, 212, 255, 0.2);
  border-radius: 3px;
  transform: rotate(8deg);
}
.card-illust-pages::before {
  content: '';
  position: absolute;
  top: 2px; left: 2px; right: 2px; bottom: 2px;
  background: repeating-linear-gradient(
    to bottom,
    rgba(0, 212, 255, 0.1) 0px,
    rgba(0, 212, 255, 0.1) 2px,
    transparent 2px,
    transparent 6px
  );
}

/* 预警卡片 — 脉冲波纹 */
.card-alert .card-illust-bg {
  background: linear-gradient(135deg, rgba(255, 68, 68, 0.12), rgba(0, 212, 255, 0.08));
}
.card-illust-alert {
  position: absolute;
  width: 40px; height: 40px;
  right: 15px; bottom: 10px;
  border-radius: 50%;
  border: 2px solid rgba(255, 68, 68, 0.3);
  animation: alertRing 1.5s ease-in-out infinite;
}
.card-illust-alert::before {
  content: '';
  position: absolute;
  top: -8px; left: -8px; right: -8px; bottom: -8px;
  border-radius: 50%;
  border: 1px solid rgba(255, 68, 68, 0.15);
  animation: alertRing 1.5s ease-in-out infinite 0.4s;
}
.card-illust-alert::after {
  content: '';
  position: absolute;
  top: -16px; left: -16px; right: -16px; bottom: -16px;
  border-radius: 50%;
  border: 1px solid rgba(255, 68, 68, 0.08);
  animation: alertRing 1.5s ease-in-out infinite 0.8s;
}
@keyframes alertRing {
  0%, 100% { transform: scale(1); opacity: 0.5; }
  50% { transform: scale(1.3); opacity: 0; }
}

/* 测验卡片 — 大脑波纹 */
.card-quiz .card-illust-bg {
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.12), rgba(0, 212, 255, 0.08));
}
.card-illust-brain {
  position: absolute;
  width: 50px; height: 50px;
  right: 12px; bottom: 8px;
  border-radius: 50%;
  border: 2px solid rgba(168, 85, 247, 0.2);
  animation: brainPulse 2s ease-in-out infinite;
}
.card-illust-brain::before {
  content: '';
  position: absolute;
  top: -6px; left: -6px; right: -6px; bottom: -6px;
  border-radius: 50%;
  border: 1px solid rgba(0, 212, 255, 0.15);
  animation: brainPulse 2s ease-in-out infinite 0.5s;
}
@keyframes brainPulse {
  0%, 100% { transform: scale(1); opacity: 0.4; }
  50% { transform: scale(1.2); opacity: 0.8; }
}

/* --- 按钮 --- */
.btn {
  display: inline-block;
  padding: 10px 24px;
  border-radius: var(--radius-sm);
  border: none;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: var(--transition);
  background: linear-gradient(135deg, var(--color-primary), #0090b0);
  color: #0b0e1a;
}

.btn:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 20px var(--color-shadow);
}

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

.btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}

.btn-secondary:hover {
  background: rgba(0, 212, 255, 0.1);
}

/* --- 页面容器 --- */
.page-container {
  max-width: 900px;
  margin: 0 auto;
  padding: 20px 0;
}

.page-container.wide {
  max-width: 1100px;
}

/* --- 返回首页链接 --- */
.back-home {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  margin-bottom: 20px;
  transition: var(--transition);
}

.back-home:hover {
  color: var(--color-primary);
  transform: translateX(-4px);
}

/* --- 内容卡片（内页） --- */
.content-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
  padding: 28px 24px;
  margin-bottom: 20px;
  backdrop-filter: blur(4px);
}

.content-card h2 {
  font-size: 1.5rem;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.content-card p, .content-card li {
  color: var(--color-text);
  font-size: 0.95rem;
  line-height: 1.8;
}

/* --- 列表样式 --- */
.emoji-list {
  list-style: none;
  padding: 0;
}

.emoji-list li {
  padding: 8px 0;
  border-bottom: 1px solid rgba(255,255,255,0.05);
}

.emoji-list li:last-child {
  border-bottom: none;
}

/* --- 动画: 渐入 --- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

.fade-in {
  animation: fadeInUp 0.5s ease forwards;
}

.fade-in-delay-1 { animation-delay: 0.1s; }
.fade-in-delay-2 { animation-delay: 0.2s; }
.fade-in-delay-3 { animation-delay: 0.3s; }
.fade-in-delay-4 { animation-delay: 0.4s; }

/* --- 脉冲动画（用于模拟器） --- */
@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50%      { transform: scale(1.08); opacity: 0.7; }
}

.pulse {
  animation: pulse 1.2s ease-in-out infinite;
}

/* --- 响应式 --- */
@media (max-width: 600px) {
  body { padding: 12px; }
  .gradient-title { font-size: 1.6rem; }
  .card-grid { grid-template-columns: 1fr; }
  .card { padding: 20px 16px; }
  .nav-bar a { font-size: 0.85rem; padding: 6px 14px; }
  .content-card { padding: 20px 16px; }
}