/* ============================================================
   沙尘暴3D科普网站 — 共享样式表
   暗色科技风 · 沙尘色系点缀 · 微动效 · 响应式
   ============================================================ */

/* ----- CSS 自定义属性（主题色）----- */
:root {
  --color-bg-start: #1a1d2e;
  --color-bg-mid: #1e2235;
  --color-bg-end: #252a3e;
  --color-surface: #2a2f45;
  --color-surface-hover: #323852;
  --color-border: #3a3f58;
  --color-text: #d0d3e0;
  --color-text-muted: #8b8fa8;
  --color-text-bright: #f0f2f8;
  --color-gold: #e8b86d;
  --color-sand: #c49a6c;
  --color-warm-sand: #d4a574;
  --color-accent: #e8b86d;
  --color-danger: #e05555;
  --color-success: #5cb878;
  --color-info: #5b9bd5;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.35);
  --shadow-hover: 0 8px 32px rgba(0, 0, 0, 0.5);
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --font-stack: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
}

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

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

body {
  font-family: var(--font-stack);
  background: linear-gradient(160deg, var(--color-bg-start) 0%, var(--color-bg-mid) 40%, var(--color-bg-end) 100%);
  color: var(--color-text);
  line-height: 1.7;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* ----- 链接 ----- */
a {
  color: var(--color-gold);
  text-decoration: none;
  transition: color var(--transition-fast);
}
a:hover {
  color: var(--color-warm-sand);
}

/* ----- 语义化布局 ----- */
header, nav, main, article, section, footer {
  display: block;
}

/* ----- 导航栏 ----- */
.navbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  padding: 16px 24px;
  background: rgba(42, 47, 69, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.navbar .logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-gold);
  letter-spacing: 0.5px;
}
.navbar .nav-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  list-style: none;
}
.navbar .nav-links a {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}
.navbar .nav-links a:hover,
.navbar .nav-links a.active {
  color: var(--color-gold);
  border-bottom-color: var(--color-gold);
}

/* ----- 页面容器 ----- */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 32px 20px 60px;
}

/* ----- 标题 ----- */
.page-title {
  font-size: 2.2rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: 12px;
  background: linear-gradient(135deg, var(--color-gold) 0%, var(--color-warm-sand) 50%, #f0d78c 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.page-subtitle {
  text-align: center;
  color: var(--color-text-muted);
  font-size: 1.05rem;
  margin-bottom: 36px;
}

/* ----- 卡片 ----- */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-card);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}
.card-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-gold);
  margin-bottom: 10px;
}
.card-text {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* ----- 按钮 ----- */
.btn {
  display: inline-block;
  padding: 10px 22px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all var(--transition-fast);
  font-family: var(--font-stack);
  text-align: center;
}
.btn-primary {
  background: linear-gradient(135deg, var(--color-gold), var(--color-sand));
  color: #1a1d2e;
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(232, 184, 109, 0.35);
}
.btn-outline {
  background: transparent;
  border: 2px solid var(--color-gold);
  color: var(--color-gold);
}
.btn-outline:hover {
  background: var(--color-gold);
  color: #1a1d2e;
}
.btn-danger {
  background: var(--color-danger);
  color: #fff;
}
.btn-sm {
  padding: 6px 14px;
  font-size: 0.85rem;
}

/* ----- 表单 ----- */
.input, .textarea {
  width: 100%;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  background: var(--color-bg-end);
  color: var(--color-text);
  font-family: var(--font-stack);
  font-size: 0.95rem;
  transition: border-color var(--transition-fast);
}
.input:focus, .textarea:focus {
  outline: none;
  border-color: var(--color-gold);
}
.textarea {
  resize: vertical;
  min-height: 100px;
}

/* ----- 网格布局 ----- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 18px;
}

/* ----- 标签 / 徽章 ----- */
.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 20px;
  font-size: 0.78rem;
  font-weight: 600;
}
.badge-gold {
  background: rgba(232, 184, 109, 0.2);
  color: var(--color-gold);
}
.badge-danger {
  background: rgba(224, 85, 85, 0.2);
  color: var(--color-danger);
}
.badge-info {
  background: rgba(91, 155, 213, 0.2);
  color: var(--color-info);
}

/* ----- 分割线 ----- */
.divider {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: 32px 0;
}

/* ----- Toast 提示 ----- */
.toast {
  position: fixed;
  top: 20px;
  right: 20px;
  background: var(--color-surface);
  border: 1px solid var(--color-gold);
  border-radius: var(--radius-sm);
  padding: 12px 20px;
  color: var(--color-text-bright);
  font-size: 0.9rem;
  z-index: 999;
  opacity: 0;
  transform: translateX(40px);
  transition: all var(--transition-normal);
  pointer-events: none;
}
.toast.show {
  opacity: 1;
  transform: translateX(0);
}

/* ----- 模态弹层 ----- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}
.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}
.modal-box {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 28px;
  max-width: 500px;
  width: 90%;
  box-shadow: var(--shadow-hover);
}

/* ----- 页脚 ----- */
.footer {
  text-align: center;
  padding: 24px;
  color: var(--color-text-muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--color-border);
  margin-top: 40px;
}

/* ----- 响应式 ----- */
@media (max-width: 768px) {
  .navbar {
    flex-direction: column;
    align-items: flex-start;
  }
  .page-title {
    font-size: 1.6rem;
  }
  .container {
    padding: 20px 14px 40px;
  }
  .grid-2, .grid-3 {
    grid-template-columns: 1fr;
  }
}

/* ----- 3D 画布容器 ----- */
.canvas-container {
  position: relative;
  width: 100%;
  height: 500px;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border);
  background: #0d0f18;
}
.canvas-container canvas {
  display: block;
}
.canvas-container .overlay-controls {
  position: absolute;
  bottom: 16px;
  left: 16px;
  right: 16px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  z-index: 10;
}

/* ----- 3D 模拟可折叠面板 ----- */
.panel-toggle {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 20px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  margin-bottom: 0;
  transition: all var(--transition-fast);
  user-select: none;
}
.panel-toggle:hover {
  border-color: var(--color-gold);
}
.panel-toggle-icon {
  font-size: 1.3rem;
}
.panel-toggle-arrow {
  margin-left: auto;
  transition: transform var(--transition-normal);
  font-size: 0.8rem;
  color: var(--color-text-muted);
}
.panel-toggle.collapsed .panel-toggle-arrow {
  transform: rotate(-90deg);
}
.canvas-panel {
  overflow: hidden;
  transition: max-height 0.4s ease, opacity 0.3s ease, margin 0.3s ease;
  max-height: 600px;
  opacity: 1;
  margin-bottom: 32px;
}
.canvas-panel.collapsed {
  max-height: 0;
  opacity: 0;
  margin-bottom: 0;
}

/* ----- 新手指引弹窗 ----- */
.guide-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.75);
  z-index: 300;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}
.guide-overlay.active {
  opacity: 1;
  pointer-events: auto;
}
.guide-box {
  background: var(--color-surface);
  border: 1px solid var(--color-gold);
  border-radius: var(--radius-lg);
  padding: 0;
  max-width: 520px;
  width: 90%;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: var(--shadow-hover);
}
.guide-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 22px;
  border-bottom: 1px solid var(--color-border);
  font-weight: 700;
  color: var(--color-gold);
  font-size: 1.1rem;
}
.guide-close {
  background: none;
  border: none;
  color: var(--color-text-muted);
  font-size: 1.3rem;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: 4px;
  transition: color var(--transition-fast);
}
.guide-close:hover {
  color: var(--color-text-bright);
}
.guide-body {
  padding: 20px 22px;
}
.guide-step {
  display: flex;
  gap: 14px;
  margin-bottom: 16px;
  align-items: flex-start;
}
.guide-step:last-child {
  margin-bottom: 0;
}
.guide-num {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-gold);
  color: #1a1d2e;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.85rem;
  flex-shrink: 0;
}
.guide-step div {
  font-size: 0.9rem;
  color: var(--color-text);
  line-height: 1.55;
}
.guide-step div strong {
  color: var(--color-gold);
}

/* ----- 文章内容样式 ----- */
.article-body h2 {
  font-size: 1.5rem;
  color: var(--color-gold);
  margin: 36px 0 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-border);
}
.article-body h3 {
  font-size: 1.15rem;
  color: var(--color-warm-sand);
  margin: 24px 0 10px;
}
.article-body p {
  margin-bottom: 14px;
  color: var(--color-text);
  text-align: justify;
}
.article-body strong {
  color: var(--color-gold);
  font-weight: 700;
}
.article-body .easter-egg {
  display: inline-block;
  cursor: pointer;
  border-bottom: 2px dashed var(--color-gold);
  color: var(--color-gold);
  transition: color var(--transition-fast);
}
.article-body .easter-egg:hover {
  color: var(--color-warm-sand);
}

/* ----- 风险等级色标 ----- */
.level-safe { color: #5cb878; }
.level-moderate { color: #e8b86d; }
.level-unhealthy { color: #e8a040; }
.level-hazardous { color: #e05555; }

/* ----- 留言墙 ----- */
.message-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin-bottom: 12px;
  transition: transform var(--transition-fast);
}
.message-item:hover {
  transform: translateX(4px);
}
.message-item .msg-meta {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-bottom: 6px;
}
.message-item .msg-body {
  color: var(--color-text-bright);
  font-size: 0.95rem;
}