/* ============================================
   安全小卫士 — 共享样式表
   暗色渐变主题 · 毛玻璃卡片 · 霓虹动效
   ============================================ */

/* --- CSS 自定义属性（主题色） --- */
:root {
  --color-primary: #00d4ff;
  --color-secondary: #7c3aed;
  --color-accent: #f59e0b;
  --color-danger: #ef4444;
  --color-success: #10b981;
  --color-bg-start: #0a0e27;
  --color-bg-end: #1a1040;
  --color-card-bg: rgba(255, 255, 255, 0.06);
  --color-card-border: rgba(255, 255, 255, 0.1);
  --color-text: #e0e0e0;
  --color-text-dim: #9ca3af;
  --color-text-bright: #ffffff;
  --color-glow: rgba(0, 212, 255, 0.3);
  --radius: 16px;
  --radius-sm: 10px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC",
               "Microsoft YaHei", "Helvetica Neue", sans-serif;
  background: linear-gradient(135deg, var(--color-bg-start), var(--color-bg-end));
  color: var(--color-text);
  min-height: 100vh;
  line-height: 1.6;
  padding: 20px;
}

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

.gradient-subtitle {
  font-size: 1.1rem;
  color: var(--color-text-dim);
  text-align: center;
  margin-bottom: 2rem;
}

/* --- 导航栏 --- */
.nav-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto 2rem;
  padding: 12px 24px;
  background: var(--color-card-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
}

.nav-bar .logo {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--color-text-bright);
  text-decoration: none;
}

.nav-bar .logo span {
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  gap: 16px;
  list-style: none;
}

.nav-links a {
  color: var(--color-text-dim);
  text-decoration: none;
  font-size: 0.9rem;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.nav-links a:hover {
  color: var(--color-text-bright);
  background: rgba(255, 255, 255, 0.08);
}

/* --- 卡片容器 --- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
  max-width: 1200px;
  margin: 0 auto;
}

/* --- 卡片 --- */
.card {
  background: var(--color-card-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
  padding: 24px;
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  right: -2px;
  bottom: -2px;
  border-radius: calc(var(--radius) + 2px);
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  opacity: 0;
  z-index: -1;
  transition: var(--transition);
}

.card:hover {
  transform: translateY(-6px);
  border-color: transparent;
}

.card:hover::before {
  opacity: 1;
}

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

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

.card h3 {
  font-size: 1.15rem;
  color: var(--color-text-bright);
  margin-bottom: 8px;
}

.card p {
  font-size: 0.85rem;
  color: var(--color-text-dim);
  line-height: 1.5;
}

/* --- 按钮 --- */
.btn {
  display: inline-block;
  padding: 12px 28px;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  color: var(--color-text-bright);
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  position: relative;
  overflow: hidden;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--color-glow);
}

.btn:active {
  transform: scale(0.96);
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.85rem;
}

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

.btn-outline:hover {
  background: var(--color-primary);
  color: #fff;
}

.btn-back {
  background: rgba(255, 255, 255, 0.08);
  color: var(--color-text-dim);
  margin-bottom: 1rem;
}

.btn-back:hover {
  background: rgba(255, 255, 255, 0.15);
  color: var(--color-text-bright);
}

/* --- 内容区域（图文讲解页用） --- */
.content-page {
  max-width: 900px;
  margin: 0 auto;
}

.content-section {
  background: var(--color-card-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 24px;
}

.content-section h2 {
  font-size: 1.6rem;
  color: var(--color-text-bright);
  margin-bottom: 16px;
}

.content-section .big-icon {
  font-size: 4rem;
  text-align: center;
  display: block;
  margin-bottom: 16px;
}

.content-section p {
  margin-bottom: 12px;
  line-height: 1.8;
}

.content-section ul {
  padding-left: 24px;
  margin-bottom: 12px;
}

.content-section li {
  margin-bottom: 8px;
  line-height: 1.6;
}

/* --- 动画容器（模拟视频） --- */
.animation-box {
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius);
  padding: 40px 20px;
  text-align: center;
  margin: 20px 0;
  border: 1px dashed var(--color-card-border);
  position: relative;
  overflow: hidden;
  min-height: 180px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.animation-box .anim-icon {
  font-size: 4rem;
  animation: float 2s ease-in-out infinite;
}

.animation-box .anim-label {
  color: var(--color-text-dim);
  font-size: 0.9rem;
  margin-top: 12px;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

/* --- 游戏/模拟场景弹窗 --- */
.modal-overlay {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal-overlay.active {
  display: flex;
}

.modal-box {
  background: linear-gradient(135deg, #1a1040, #0f0a2a);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
  padding: 32px;
  max-width: 600px;
  width: 100%;
  max-height: 80vh;
  overflow-y: auto;
  position: relative;
  animation: modalIn 0.3s ease-out;
}

@keyframes modalIn {
  from { transform: scale(0.9) translateY(20px); opacity: 0; }
  to { transform: scale(1) translateY(0); opacity: 1; }
}

.modal-box h2 {
  color: var(--color-text-bright);
  margin-bottom: 16px;
  text-align: center;
}

.modal-box .question {
  font-size: 1.15rem;
  color: var(--color-text);
  margin-bottom: 20px;
  text-align: center;
  line-height: 1.7;
}

.modal-box .options {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.modal-box .option-btn {
  padding: 14px 20px;
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.05);
  color: var(--color-text);
  font-size: 1rem;
  cursor: pointer;
  transition: var(--transition);
  text-align: left;
}

.modal-box .option-btn:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: var(--color-primary);
  transform: translateX(4px);
}

.modal-box .option-btn.correct {
  background: rgba(16, 185, 129, 0.2);
  border-color: var(--color-success);
  color: var(--color-success);
}

.modal-box .option-btn.wrong {
  background: rgba(239, 68, 68, 0.2);
  border-color: var(--color-danger);
  color: var(--color-danger);
}

.modal-box .feedback {
  margin-top: 16px;
  padding: 16px;
  border-radius: var(--radius-sm);
  text-align: center;
  font-size: 1rem;
  line-height: 1.6;
}

.modal-box .feedback.success {
  background: rgba(16, 185, 129, 0.15);
  color: var(--color-success);
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.modal-box .feedback.fail {
  background: rgba(239, 68, 68, 0.15);
  color: var(--color-danger);
  border: 1px solid rgba(239, 68, 68, 0.3);
}

.modal-box .close-btn {
  position: absolute;
  top: 12px;
  right: 16px;
  background: none;
  border: none;
  color: var(--color-text-dim);
  font-size: 1.5rem;
  cursor: pointer;
  transition: var(--transition);
}

.modal-box .close-btn:hover {
  color: var(--color-text-bright);
  transform: rotate(90deg);
}

/* --- 年龄选择页（首页） --- */
.age-selector {
  display: flex;
  gap: 24px;
  justify-content: center;
  flex-wrap: wrap;
  max-width: 900px;
  margin: 0 auto 3rem;
}

.age-card {
  flex: 1;
  min-width: 200px;
  max-width: 280px;
  background: var(--color-card-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
  padding: 32px 20px;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
}

.age-card:hover {
  transform: translateY(-8px);
  border-color: var(--color-primary);
  box-shadow: 0 12px 40px var(--color-glow);
}

.age-card:active {
  transform: scale(0.96);
}

.age-card .age-icon {
  font-size: 3.5rem;
  margin-bottom: 12px;
}

.age-card h2 {
  font-size: 1.4rem;
  color: var(--color-text-bright);
  margin-bottom: 6px;
}

.age-card p {
  font-size: 0.85rem;
  color: var(--color-text-dim);
}

/* --- 安全分类按钮网格 --- */
.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 16px;
  max-width: 1200px;
  margin: 0 auto;
}

.category-btn {
  padding: 20px 16px;
  background: var(--color-card-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--color-card-border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
  color: var(--color-text);
  font-size: 0.95rem;
}

.category-btn:hover {
  transform: translateY(-4px);
  border-color: var(--color-primary);
  box-shadow: 0 6px 20px var(--color-glow);
}

.category-btn:active {
  transform: scale(0.96);
}

.category-btn .cat-icon {
  font-size: 2.2rem;
  display: block;
  margin-bottom: 8px;
}

/* --- 响应式 --- */
@media (max-width: 768px) {
  body { padding: 12px; }
  .gradient-title { font-size: 1.6rem; }
  .nav-bar { flex-direction: column; gap: 10px; }
  .nav-links { flex-wrap: wrap; justify-content: center; }
  .age-selector { flex-direction: column; align-items: center; }
  .age-card { max-width: 100%; }
  .card-grid { grid-template-columns: 1fr; }
  .category-grid { grid-template-columns: repeat(2, 1fr); }
  .content-section { padding: 20px; }
  .modal-box { padding: 20px; }
}

@media (max-width: 480px) {
  .category-grid { grid-template-columns: 1fr; }
  .gradient-title { font-size: 1.3rem; }
}

/* --- 工具类 --- */
.text-center { text-align: center; }
.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.flex-center { display: flex; align-items: center; justify-content: center; }