/* ==========================================================================
   DeepSeek 徽派马头墙风说明书视觉系统
   设计隐喻：马头墙层层跌落，"DeepSeek官网"为最高墙头，功能为瓦当，骨架为阶梯跌落轮廓，黛瓦配粉墙
   ========================================================================== */

:root {
  /* 粉墙白与宣纸基底 */
  --wall-bg: #f7f8f9;
  --wall-surface: #ffffff;
  --wall-subtle: #edf0f3;
  --wall-border: #d7dde3;
  --wall-slate: #475569;
  --wall-deep: #1e293b;
  
  /* 黛瓦墨灰主色与最高墙头 */
  --brick-dai: #2d3748;
  --brick-dai-hover: #1a202c;
  --brick-dai-light: #f1f5f9;
  --brick-crest: #1a202c;

  /* 瓦当印章朱砂强调色 */
  --crest-cinnabar: #b91c1c;
  --crest-cinnabar-light: #fef2f2;
  --crest-cinnabar-border: #fecaca;
  --crest-cinnabar-hover: #991b1b;
  --crest-glow: rgba(185, 28, 28, 0.18);
  
  /* 阶梯跌落轮廓与卡片圆角阴影 */
  --shadow-sm: 0 2px 6px rgba(45, 55, 72, 0.04);
  --shadow-md: 0 8px 24px rgba(45, 55, 72, 0.08);
  --shadow-lg: 0 16px 36px rgba(26, 32, 44, 0.12);
  --radius-stepped: 16px 4px 16px 4px;
  --radius-smooth: 10px;
  --radius-pill: 9999px;
  
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
  --font-mono: "SF Mono", Consolas, "Liberation Mono", Menlo, Courier, monospace;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--wall-bg);
  color: var(--wall-slate);
}

body {
  font-family: var(--font-sans);
  line-height: 1.68;
  background: 
    radial-gradient(circle at 10% 12%, rgba(185, 28, 28, 0.03) 0%, transparent 40%),
    radial-gradient(circle at 90% 88%, rgba(45, 55, 72, 0.04) 0%, transparent 40%),
    linear-gradient(180deg, #fbfcfd 0%, #f1f4f7 100%);
  color: var(--wall-slate);
  overflow-x: hidden;
  min-height: 100vh;
}

/* 阶梯马头墙跌落轮廓肌理 */
.huizhou-stepped-bg {
  background-image: repeating-linear-gradient(
    180deg,
    transparent,
    transparent 48px,
    rgba(215, 221, 227, 0.3) 48px,
    rgba(215, 221, 227, 0.3) 49px
  );
}

/* 居中版心：1100px 左右留白 */
.container {
  width: 100%;
  max-width: 1100px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* 顶栏 Sticky Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 2px solid var(--brick-crest);
  box-shadow: 0 1px 6px rgba(45, 55, 72, 0.04);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.brand-area {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand-logo {
  width: 34px;
  height: 34px;
  object-fit: contain;
  border-radius: 8px;
  border: 1px solid var(--wall-border);
  background: #ffffff;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--brick-crest);
  letter-spacing: -0.02em;
}

.brand-subtitle {
  font-size: 0.72rem;
  color: var(--crest-cinnabar);
  font-weight: 600;
  letter-spacing: 0.04em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  list-style: none;
}

.nav-link {
  color: var(--wall-slate);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  transition: all 0.2s ease;
  padding: 6px 10px;
  border-radius: 6px;
}

.nav-link:hover {
  color: var(--crest-cinnabar);
  background-color: var(--crest-cinnabar-light);
}

.nav-btn {
  background: var(--brick-crest);
  color: #ffffff !important;
  font-weight: 600;
  padding: 8px 18px !important;
  border-radius: var(--radius-smooth) !important;
  box-shadow: 0 2px 10px rgba(26, 32, 44, 0.2);
}

.nav-btn:hover {
  background: var(--crest-cinnabar) !important;
  box-shadow: 0 4px 14px rgba(185, 28, 28, 0.3);
}

/* 说明白卡片通用风格 */
.white-card {
  background: var(--wall-surface);
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-stepped);
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
  position: relative;
  overflow: hidden;
}

.white-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--crest-cinnabar);
}

/* 黛瓦马头墙顶饰条 */
.white-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--brick-crest), var(--crest-cinnabar), transparent);
  opacity: 0.7;
}

/* Hero 左右栏 */
.hero-section {
  padding: 56px 0 44px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 36px;
  align-items: center;
}

.hero-content {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.hero-meta-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.pill-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--crest-cinnabar-light);
  border: 1px solid var(--crest-cinnabar-border);
  color: var(--crest-cinnabar);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
}

.pill-date {
  font-size: 0.82rem;
  color: #64748b;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.hero-h1 {
  font-size: 2.25rem;
  line-height: 1.25;
  font-weight: 800;
  color: var(--brick-crest);
  letter-spacing: -0.03em;
}

.hero-h1 .h1-sub {
  display: block;
  font-size: 1.25rem;
  color: var(--crest-cinnabar);
  font-weight: 600;
  margin-top: 8px;
  letter-spacing: 0;
}

.hero-intro {
  font-size: 1.05rem;
  color: #334155;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 8px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--brick-crest);
  color: #ffffff;
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  padding: 13px 28px;
  border-radius: var(--radius-smooth);
  border: 1px solid rgba(255,255,255,0.1);
  box-shadow: 0 4px 14px rgba(26, 32, 44, 0.25);
  transition: all 0.2s ease;
  cursor: pointer;
}

.btn-primary:hover {
  background: var(--brick-dai-hover);
  box-shadow: 0 6px 18px rgba(26, 32, 44, 0.35);
  transform: translateY(-1px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: #ffffff;
  color: var(--wall-slate);
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  padding: 13px 24px;
  border-radius: var(--radius-smooth);
  border: 1px solid var(--wall-border);
  box-shadow: var(--shadow-sm);
  transition: all 0.2s ease;
  cursor: pointer;
}

.btn-secondary:hover {
  border-color: var(--crest-cinnabar);
  color: var(--crest-cinnabar);
  background: var(--crest-cinnabar-light);
}

/* Hero 右侧拟真展示区（假界面/假对话/马头墙跌落轮廓） */
.hero-visual {
  background: linear-gradient(145deg, #ffffff 0%, #edf2f7 100%);
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-stepped);
  padding: 20px;
  box-shadow: var(--shadow-md);
  position: relative;
}

.visual-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--wall-border);
  margin-bottom: 14px;
}

.dot-group {
  display: flex;
  gap: 6px;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #cbd5e1;
}

.dot.active {
  background: var(--crest-cinnabar);
}

.visual-title {
  font-size: 0.78rem;
  font-family: var(--font-mono);
  color: #64748b;
}

.mock-dialog {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.dialog-msg {
  padding: 12px 16px;
  border-radius: 12px;
  font-size: 0.88rem;
  line-height: 1.5;
}

.dialog-user {
  align-self: flex-end;
  background: var(--crest-cinnabar-light);
  border: 1px solid var(--crest-cinnabar-border);
  color: var(--brick-crest);
  max-width: 88%;
}

.dialog-ai {
  align-self: flex-start;
  background: #ffffff;
  border: 1px solid var(--wall-border);
  color: var(--wall-slate);
  max-width: 95%;
  box-shadow: 0 2px 6px rgba(0,0,0,0.03);
}

.ai-crest-label {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--crest-cinnabar);
  margin-bottom: 4px;
}

.visual-img-wrap {
  margin-top: 12px;
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid var(--wall-border);
}

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

/* 章节通用标题规范 */
.section-wrap {
  padding: 48px 0;
}

.section-head {
  text-align: center;
  margin-bottom: 36px;
}

.section-h2 {
  font-size: 1.85rem;
  font-weight: 800;
  color: var(--brick-crest);
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.section-desc {
  font-size: 0.98rem;
  color: #64748b;
  max-width: 680px;
  margin: 0 auto;
}

/* 3. 特色区块：H2 + 横条 + 补充卡 */
.features-grid {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.feature-bar {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 24px;
  padding: 22px 28px;
  background: #ffffff;
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-smooth);
  box-shadow: var(--shadow-sm);
  align-items: center;
  transition: border-color 0.2s ease;
}

.feature-bar:hover {
  border-color: var(--crest-cinnabar);
}

.bar-title-area {
  display: flex;
  align-items: center;
  gap: 12px;
}

.bar-icon-badge {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  background: var(--crest-cinnabar-light);
  color: var(--crest-cinnabar);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
}

.bar-h3 {
  font-size: 1.08rem;
  font-weight: 700;
  color: var(--brick-crest);
}

.bar-desc {
  font-size: 0.93rem;
  color: #475569;
  line-height: 1.6;
}

.feature-cards-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-top: 12px;
}

.extra-card {
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.card-img-holder {
  width: 100%;
  height: 170px;
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid var(--wall-border);
  background: #edf2f7;
}

.card-img-holder img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* 4. 步骤区块：4步序号卡片 */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.step-card {
  padding: 26px 20px;
  background: #ffffff;
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-smooth);
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.step-num {
  font-family: var(--font-mono);
  font-size: 1.8rem;
  font-weight: 900;
  color: var(--crest-cinnabar);
  line-height: 1;
}

.step-h3 {
  font-size: 1.08rem;
  font-weight: 700;
  color: var(--brick-crest);
}

.step-desc {
  font-size: 0.88rem;
  color: #556975;
  line-height: 1.6;
}

/* 5. 对照清单：深色大卡（黛瓦沉木大卡） */
.dark-checklist-card {
  background: linear-gradient(145deg, #1a202c 0%, #0f172a 100%);
  border: 1px solid #334155;
  border-radius: var(--radius-stepped);
  padding: 38px 34px;
  color: #cbd5e1;
  box-shadow: var(--shadow-lg);
  margin-top: 10px;
}

.checklist-h3 {
  color: #ffffff;
  font-size: 1.45rem;
  font-weight: 700;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.checklist-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}

.check-column h4 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.check-column.wrong h4 {
  color: #f87171;
}

.check-column.correct h4 {
  color: #38bdf8;
}

.check-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.check-item {
  font-size: 0.92rem;
  line-height: 1.55;
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.check-item::before {
  content: "•";
  font-weight: bold;
}

.wrong .check-item::before {
  color: #f87171;
}

.correct .check-item::before {
  color: #38bdf8;
}

/* 6. 场景：4个具体岗位气泡卡 */
.personas-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.persona-card {
  padding: 22px 18px;
  background: #ffffff;
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-stepped);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.persona-badge {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--crest-cinnabar);
  background: var(--crest-cinnabar-light);
  border: 1px solid var(--crest-cinnabar-border);
  padding: 3px 8px;
  border-radius: 6px;
  align-self: flex-start;
}

.persona-role {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--brick-crest);
}

.persona-quote {
  font-size: 0.88rem;
  color: #475569;
  line-height: 1.6;
  font-style: normal;
  background: #f8fafc;
  padding: 10px 12px;
  border-left: 3px solid var(--crest-cinnabar);
  border-radius: 0 6px 6px 0;
}

.persona-action {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--wall-slate);
  margin-top: auto;
  padding-top: 8px;
  border-top: 1px dashed var(--wall-border);
}

/* 7. 小技巧：3列短卡 */
.tips-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.tip-card {
  padding: 24px;
  background: #ffffff;
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-smooth);
}

.tip-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--brick-crest);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.tip-card p {
  font-size: 0.9rem;
  color: #556975;
  line-height: 1.65;
}

/* 8. 卡点笔记：失败现象 + 处理顺序 */
.trouble-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.trouble-card {
  padding: 24px;
  background: #ffffff;
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-smooth);
  box-shadow: var(--shadow-sm);
}

.trouble-issue {
  background: #fef2f2;
  border: 1px solid #fee2e2;
  padding: 12px 14px;
  border-radius: 8px;
  margin-bottom: 14px;
}

.trouble-issue-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #991b1b;
  display: flex;
  align-items: center;
  gap: 6px;
}

.trouble-issue-desc {
  font-size: 0.85rem;
  color: #7f1d1d;
  margin-top: 4px;
}

.trouble-steps-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--brick-crest);
  margin-bottom: 8px;
}

.trouble-steps-list {
  padding-left: 20px;
  font-size: 0.88rem;
  color: #475569;
  line-height: 1.6;
}

.trouble-steps-list li {
  margin-bottom: 4px;
}

/* 9. FAQ：8条手风琴 */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: #ffffff;
  border: 1px solid var(--wall-border);
  border-radius: var(--radius-smooth);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item[open] {
  border-color: var(--crest-cinnabar-border);
  box-shadow: var(--shadow-sm);
}

.faq-summary {
  padding: 16px 20px;
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--brick-crest);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

.faq-summary::-webkit-details-marker {
  display: none;
}

.faq-summary::after {
  content: "+";
  font-size: 1.4rem;
  font-weight: 400;
  color: var(--crest-cinnabar);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-summary::after {
  content: "−";
  transform: rotate(180deg);
}

.faq-content {
  padding: 0 20px 18px;
  font-size: 0.92rem;
  color: #475569;
  line-height: 1.7;
  border-top: 1px dashed var(--wall-subtle);
  padding-top: 14px;
}

/* 10. 资讯：8条带日期标题 + 底部新鲜度 */
.news-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.news-item {
  padding: 14px 18px;
  background: #ffffff;
  border: 1px solid var(--wall-border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  text-decoration: none;
  transition: all 0.2s ease;
}

.news-item:hover {
  border-color: var(--crest-cinnabar);
  background: var(--crest-cinnabar-light);
  transform: translateX(3px);
}

.news-title {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--brick-crest);
}

.news-date {
  font-size: 0.8rem;
  color: #64748b;
  font-family: var(--font-mono);
  white-space: nowrap;
  margin-left: 12px;
}

.news-footer-time {
  margin-top: 20px;
  text-align: center;
  font-size: 0.85rem;
  color: #64748b;
}

/* 11. 收尾 CTA */
.cta-wrap {
  padding: 40px 0;
}

.cta-box {
  background: linear-gradient(135deg, #ffffff 0%, #edf2f7 100%);
  border: 1px solid var(--crest-cinnabar-border);
  border-radius: var(--radius-stepped);
  padding: 40px 32px;
  text-align: center;
  box-shadow: var(--shadow-md);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

.cta-h2 {
  font-size: 1.7rem;
  font-weight: 800;
  color: var(--brick-crest);
}

.cta-p {
  font-size: 1rem;
  color: #556975;
  max-width: 600px;
}

/* 12. Footer */
.site-footer {
  background: #0f172a;
  color: #94a3b8;
  padding: 56px 0 32px;
  border-top: 2px solid var(--crest-cinnabar);
  font-size: 0.88rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 36px;
  margin-bottom: 40px;
}

.footer-brand h3 {
  color: #ffffff;
  font-size: 1.2rem;
  margin-bottom: 10px;
}

.footer-brand p {
  line-height: 1.6;
  color: #94a3b8;
}

.footer-col h4 {
  color: #ffffff;
  font-size: 0.98rem;
  margin-bottom: 14px;
  font-weight: 700;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer-links a {
  color: #94a3b8;
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: #ffffff;
}

.footer-bottom {
  border-top: 1px solid #1e293b;
  padding-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: #64748b;
  flex-wrap: wrap;
  gap: 12px;
}

/* 响应式断点规范 */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }
  .feature-bar {
    grid-template-columns: 1fr;
    gap: 10px;
  }
  .feature-cards-row {
    grid-template-columns: 1fr;
  }
  .steps-grid {
    grid-template-columns: 1fr 1fr;
  }
  .checklist-grid {
    grid-template-columns: 1fr;
  }
  .personas-grid {
    grid-template-columns: 1fr 1fr;
  }
  .tips-grid {
    grid-template-columns: 1fr;
  }
  .trouble-grid {
    grid-template-columns: 1fr;
  }
  .news-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 640px) {
  .hero-h1 {
    font-size: 1.8rem;
  }
  .hero-h1 .h1-sub {
    font-size: 1.1rem;
  }
  .section-h2 {
    font-size: 1.5rem;
  }
  .steps-grid {
    grid-template-columns: 1fr;
  }
  .personas-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .nav-links {
    display: none;
  }
}

/* PERF-PATCH-20260928 */
img { max-width: 100%; }
@media (max-width: 900px) {
  header, .header, .site-header {
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
  }
}
@media (max-width: 900px), (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-iteration-count: 1 !important;
    animation-duration: 0.6s !important;
  }
}
main section:not(#hero):not(.hero) {
  content-visibility: auto;
  contain-intrinsic-size: auto 420px;
}