/* ===== 善智导航 全局样式 V3.0 · 智慧轻盈版 ===== */
/* 设计理念：毛玻璃、柔和渐变、秩序感、呼吸感 */

/* ----- 基础重置与变量 ----- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #4f46e5;
  --primary-light: #818cf8;
  --primary-dark: #3730a3;
  --bg-gradient-start: #f8fafc;
  --bg-gradient-end: #eef2ff;
  --card-bg: rgba(255, 255, 255, 0.75);
  --card-border: rgba(255, 255, 255, 0.9);
  --text-main: #1e293b;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --shadow-sm: 0 8px 20px -6px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 20px 35px -8px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 28px 45px -12px rgba(79, 70, 229, 0.12);
  --border-light: 1px solid rgba(255, 255, 255, 0.7);
  --radius-card: 28px;
  --radius-sm: 16px;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.6;
  color: var(--text-main);
  background: linear-gradient(145deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 100%);
  padding: 0 20px;
  max-width: 1400px;
  margin: 0 auto;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

html {
  scroll-behavior: smooth;
}

::selection {
  background: #a5b4fc;
  color: #1e1b4b;
}

/* ----- 版式 ----- */
h1 {
  margin: 40px 0 8px;
  font-size: 3rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #1e1b4b 0%, #3730a3 60%, #6366f1 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 4px 20px rgba(99, 102, 241, 0.15);
}

h2 {
  font-size: 2rem;
  font-weight: 700;
  margin: 48px 0 24px;
  color: #0f172a;
  letter-spacing: -0.01em;
  display: flex;
  align-items: center;
}

h2::after {
  content: "";
  flex: 1;
  height: 2px;
  background: linear-gradient(90deg, #cbd5e1, transparent);
  margin-left: 24px;
}

h3 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 16px 0 12px;
  color: #0f172a;
}

.subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 32px;
  font-weight: 400;
  border-left: 4px solid var(--primary-light);
  padding-left: 20px;
}

/* ----- 面包屑导航 ----- */
.breadcrumb {
  flex-wrap: wrap;
  font-size: 14px;
  padding: 20px 0 8px;
  color: var(--text-muted);
}

.breadcrumb a {
  color: var(--primary);
  text-decoration: none;
  padding: 4px 0;
  display: inline-block;
  font-weight: 500;
  transition: color 0.2s;
}

.breadcrumb a:hover {
  color: var(--primary-dark);
  text-decoration: underline;
}

.breadcrumb span {
  color: var(--text-main);
  font-weight: 500;
}

/* ----- 卡片系统（毛玻璃核心）----- */
.card,
.card-grid .card,
.category-card {
  background: var(--card-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-radius: var(--radius-card);
  padding: 24px 26px;
  box-shadow: var(--shadow-md), 0 0 0 1px rgba(255, 255, 255, 0.6) inset;
  border: var(--border-light);
  transition: all 0.25s cubic-bezier(0.2, 0, 0, 1);
  text-decoration: none;
  color: inherit;
  display: block;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: #cbd5e1;
  background: rgba(255, 255, 255, 0.9);
}

.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  margin: 24px 0 40px;
}

/* 卡片内链接样式 */
.card a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 500;
  margin-right: 8px;
  line-height: 1.8;
  transition: color 0.2s;
}

.card a:hover {
  color: var(--primary-dark);
  text-decoration: underline;
}

.card h3 {
  margin-top: 0;
  display: flex;
  align-items: center;
  gap: 8px;
}

.card h3 a {
  color: var(--text-main);
  text-decoration: none;
  font-weight: 700;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 8px;
}

.card-icon {
  font-size: 2.2rem;
  line-height: 1;
  margin-bottom: 8px;
}

/* 分类卡片个性化顶部边框（首页专用，全局无影响） */
.category-card {
  border-top-width: 4px;
  border-top-style: solid;
}

/* ----- 标签系统（六色胶囊等）----- */
.tag {
  display: inline-block;
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(4px);
  padding: 4px 14px;
  border-radius: 40px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-main);
  margin-right: 8px;
  margin-bottom: 8px;
  border: 1px solid rgba(255, 255, 255, 0.8);
  box-shadow: var(--shadow-sm);
}

#page-tags {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 16px;
  margin: 16px 0 24px;
}

/* 六色胶囊容器 */
.color-dots {
  display: flex;
  align-items: center;
  gap: 4px;
  background: rgba(255, 255, 255, 0.5);
  padding: 6px 18px;
  border-radius: 40px;
  backdrop-filter: blur(4px);
  border: 1px solid rgba(255, 255, 255, 0.8);
}

.dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  margin-right: 2px;
}

.dot-label {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-main);
  margin-right: 14px;
}

/* ----- 知识点关系网络（二级页面智慧模块）----- */
.kp-network {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 12px 20px;
  margin: 24px 0;
  padding: 20px 16px;
  background: rgba(255, 255, 255, 0.4);
  backdrop-filter: blur(4px);
  border-radius: var(--radius-sm);
  border: 1px dashed #cbd5e1;
}

.kp-node {
  background: rgba(255, 255, 255, 0.9);
  padding: 10px 20px;
  border-radius: 40px;
  box-shadow: var(--shadow-sm);
  font-weight: 500;
  color: var(--text-main);
  border: 1px solid #e2e8f0;
  font-size: 0.95rem;
  text-align: center;
  line-height: 1.4;
  backdrop-filter: blur(4px);
}

.kp-node small {
  font-size: 0.8rem;
  color: var(--text-muted);
  display: block;
}

.kp-arrow {
  color: #94a3b8;
  font-size: 20px;
  font-weight: 300;
}

/* ----- 学习建议卡片（智慧模块）----- */
.app-card {
  background: rgba(240, 249, 255, 0.7);
  backdrop-filter: blur(4px);
  border-left: 6px solid var(--primary);
  padding: 16px 20px;
  border-radius: 20px;
  margin: 24px 0;
  box-shadow: var(--shadow-sm);
}

.insight-badge {
  background: #eef2ff;
  color: var(--primary);
  font-size: 0.8rem;
  padding: 2px 10px;
  border-radius: 30px;
  margin-left: 10px;
  font-weight: 600;
}

/* ----- 生活应用场景网格（二级页面）----- */
.scene-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin: 20px 0;
}

.scene-card {
  background: rgba(250, 249, 254, 0.7);
  backdrop-filter: blur(4px);
  padding: 18px;
  border-radius: 20px;
  border: 1px solid rgba(255, 255, 255, 0.6);
  box-shadow: var(--shadow-sm);
}

.scene-card h3 {
  margin-top: 0;
  font-size: 1.2rem;
}

/* ----- 核心知识点列表（三色状态）----- */
.status-legend {
  display: flex;
  gap: 24px;
  margin: 20px 0 10px;
  font-size: 0.9rem;
}

.status-built { color: #2563eb; font-weight: 500; }
.status-building { color: #ea580c; }
.status-research { color: #7c3aed; }

.kp-list {
  list-style: none;
  padding: 0;
  margin: 16px 0;
}

.kp-list li {
  padding: 10px 0;
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.kp-list li a {
  font-weight: 600;
  text-decoration: none;
}

.left-quote {
  text-align: left;
  margin-top: 20px;
  color: var(--text-muted);
  font-style: italic;
  font-size: 1rem;
}

/* ----- 内部导航、资源区块 ----- */
.internal-nav,
.subject-resources,
.ai-prompts {
  margin-top: 40px;
  padding: 24px 28px;
  background: rgba(244, 247, 251, 0.6);
  backdrop-filter: blur(4px);
  border-radius: 24px;
  border: 1px solid rgba(255, 255, 255, 0.5);
}

/* ----- 页脚统一 ----- */
footer,
#site-footer {
  margin: 60px 0 30px;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.95rem;
  border-top: 1px solid rgba(0, 0, 0, 0.05);
  padding-top: 30px;
}

/* ----- 响应式 ----- */
@media (min-width: 640px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .card-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 640px) {
  h1 {
    font-size: 2.2rem;
  }

  h2 {
    font-size: 1.7rem;
  }

  .stage-grid {
    grid-template-columns: 1fr !important;
  }

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

  .breadcrumb {
    font-size: 13px;
  }

  .kp-network {
    gap: 8px;
  }

  .kp-node {
    padding: 6px 14px;
    font-size: 0.85rem;
  }
}

/* 六色学段链接颜色（用于核心分支卡片内的链接） */
.level-primary   { color: #e74c3c !important; }  /* 小学 */
.level-junior    { color: #f39c12 !important; }  /* 初中 */
.level-high      { color: #f1c40f !important; }  /* 高中 */
.level-undergrad { color: #2ecc71 !important; }  /* 本科 */
.level-grad      { color: #3498db !important; }  /* 研究生 */
.level-research  { color: #9b59b6 !important; }  /* 研究级 */

.level-primary:hover, .level-junior:hover, .level-high:hover,
.level-undergrad:hover, .level-grad:hover, .level-research:hover {
  text-decoration: underline;
}

/* 旧版三色样式兼容 */
.link-built { color: #3498db; }
.link-planned { color: #e67e22; border-bottom: 1px dashed #e67e22; cursor: help; }
.link-research { color: #8e44ad; border-bottom: 1px dashed #8e44ad; cursor: help; }
.branches-note {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 20px;
  font-style: italic;
}
/* ===== 底部固定导航 ===== */
.bottom-fixed-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: #fff;
    box-shadow: 0 -2px 12px rgba(0,0,0,0.06);
}
.nav-strip {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 14px;
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
    -webkit-overflow-scrolling: touch;
    white-space: nowrap;
    justify-content: center;
    flex-wrap: nowrap;
}
.nav-strip::-webkit-scrollbar { display: none; }
.nav-strip .nav-label {
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.5px;
    flex-shrink: 0;
    padding: 5px 10px;
    border-radius: 16px;
    white-space: nowrap;
    user-select: none;
}
.nav-strip a {
    text-decoration: none;
    font-size: 0.82rem;
    font-weight: 500;
    padding: 6px 14px;
    border-radius: 18px;
    flex-shrink: 0;
    transition: var(--transition);
    white-space: nowrap;
    display: inline-block;
}
.nav-strip a:hover { transform: translateY(-1px); box-shadow: 0 3px 10px rgba(0,0,0,0.1); }

.nav-layer-1 { background: #fff; border-bottom: 1px solid var(--border); }
.nav-layer-1 .nav-label { background: #1e293b; color: #fff; }
.nav-layer-1 a { color: #fff; }
.nav-layer-1 .subj-01 { background:#6366f1; color:#fff; }
.nav-layer-1 .subj-02 { background:#d97706; color:#fff; }
.nav-layer-1 .subj-03 { background:#a855f7; color:#fff; }
.nav-layer-1 .subj-04 { background:#475569; color:#fff; }
.nav-layer-1 .subj-05 { background:#059669; color:#fff; }
.nav-layer-1 .subj-06 { background:#ec4899; color:#fff; }
.nav-layer-1 .subj-07 { background:#f97316; color:#fff; }
.nav-layer-1 .subj-08 { background:#ef4444; color:#fff; }
.nav-layer-1 .subj-09 { background:#10b981; color:#fff; }
.nav-layer-1 .subj-10 { background:#a16207; color:#fff; }
.nav-layer-1 .subj-11 { background:#06b6d4; color:#fff; }
.nav-layer-1 a:hover { filter: brightness(1.12); }

.nav-layer-2 { background:#f1f5f9; border-top:1px solid #e2e6ed; }
.nav-layer-2 .nav-label { background:#334155; color:#f1f5f9; }
.nav-layer-2 a { background:#fff; color:#334155; border:1px solid #d4d8e0; }
.nav-layer-2 a:hover { background:#334155; color:#fff; border-color:#334155; }

/* ===== 页脚 ===== */
.site-footer {
    margin: 40px 0 30px;
    text-align: center;
    color: #94a3b8;
    font-size: 0.85rem;
    border-top: 1px solid rgba(0,0,0,0.05);
    padding-top: 28px;
    padding-bottom: 120px;
}
.site-footer a { color: var(--theme); text-decoration: none; }
.site-footer .footer-brand { font-size: 1.1rem; font-weight: 600; color: #334155; margin-bottom: 12px; }