/* ============================================================
   老蔡个人品牌官网 · 腾讯官网风格 v2.0
   视觉体系：白底 + 腾讯蓝 #0052D9 + 灰阶文字 + 卡片化 + 大留白
   ============================================================ */

:root {
  --blue: #0052D9;
  --blue-deep: #003CBE;
  --red: #D54941;
  --blue-light: #ECF2FF;
  --blue-bg: #F0F5FF;
  --ink: #1D2129;
  --ink-2: #4E5969;
  --ink-3: #86909C;
  --line: #E5E6EB;
  --bg: #FFFFFF;
  --bg-gray: #F7F8FA;
  --radius: 8px;
  --shadow: 0 8px 24px rgba(29, 33, 41, 0.08);
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.container { max-width: 1160px; margin: 0 auto; padding: 0 32px; }

/* ---------- 通用组件 ---------- */

.tag {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--blue);
  letter-spacing: 0.12em;
  margin-bottom: 16px;
}

.btn {
  display: inline-block;
  padding: 13px 32px;
  border-radius: 6px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid transparent;
}
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: var(--blue-deep); transform: translateY(-1px); }
.btn-ghost { background: #fff; color: var(--blue); border-color: var(--blue); }
.btn-ghost:hover { background: var(--blue-light); }
.btn-sm { display: inline-block; padding: 9px 24px; border-radius: 6px; font-size: 14px; font-weight: 600; background: var(--blue); color: #fff; transition: all 0.2s; }
.btn-sm:hover { background: var(--blue-deep); }

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
  height: 64px;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.logo { display: flex; align-items: baseline; gap: 10px; }
.logo-name { font-size: 22px; font-weight: 700; color: var(--ink); }
.logo-name::after { content: ""; display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--blue); margin-left: 5px; vertical-align: middle; }
.logo-sub { font-size: 12px; color: var(--ink-3); letter-spacing: 0.06em; }
.main-nav { display: flex; align-items: center; gap: 36px; }
.main-nav a { font-size: 15px; color: var(--ink-2); transition: color 0.2s; }
.main-nav a:hover { color: var(--blue); }
.nav-cta {
  padding: 8px 20px;
  border-radius: 6px;
  background: var(--blue);
  color: #fff !important;
  font-weight: 600;
  transition: background 0.2s;
}
.nav-cta:hover { background: var(--blue-deep); }

/* ---------- Hero ---------- */

.hero {
  background: linear-gradient(180deg, #F0F5FF 0%, #FFFFFF 100%);
  padding: 104px 0 96px;
}
.hero-title {
  font-size: 60px;
  line-height: 1.22;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 24px;
}
.hero-title em { font-style: normal; color: var(--blue); }
.hero-sub {
  font-size: 18px;
  color: var(--ink-2);
  max-width: 640px;
  margin-bottom: 40px;
}
.hero-ctas { display: flex; gap: 16px; margin-bottom: 64px; }
.hero-stats { display: flex; gap: 72px; border-top: 1px solid var(--line); padding-top: 36px; max-width: 720px; }
.stat-num { font-size: 44px; font-weight: 700; color: var(--blue); line-height: 1.2; }
.stat-label { font-size: 14px; color: var(--ink-3); margin-top: 4px; }

/* ---------- Section 通用 ---------- */

.section { padding: 88px 0; }
.section.gray { background: var(--bg-gray); }
.sec-head { margin-bottom: 48px; }
.sec-eyebrow { font-size: 13px; font-weight: 600; color: var(--blue); letter-spacing: 0.12em; margin-bottom: 12px; }
.sec-title { font-size: 40px; font-weight: 700; line-height: 1.3; margin-bottom: 12px; }
.sec-desc { font-size: 16px; color: var(--ink-2); max-width: 620px; }

/* ---------- 关于（首页） ---------- */

.about-wrap { display: flex; gap: 72px; align-items: center; }
.portrait-wrap {
  flex: 0 0 400px;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.about-body { flex: 1; }
.about-title { font-size: 38px; font-weight: 700; line-height: 1.3; margin-bottom: 20px; }
.about-text { font-size: 16px; color: var(--ink-2); margin-bottom: 32px; }
.timeline { display: flex; flex-direction: column; gap: 20px; }
.tl-row { display: flex; gap: 20px; align-items: baseline; padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.tl-row:last-child { border-bottom: none; padding-bottom: 0; }
.tl-year { flex: 0 0 64px; font-size: 20px; font-weight: 700; color: var(--blue); }
.tl-text { font-size: 15px; color: var(--ink-2); }

/* ---------- 卡片（我做什么） ---------- */

.cards-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 32px;
  transition: all 0.25s ease;
  display: flex;
  flex-direction: column;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: var(--blue);
}
.card-num { font-size: 14px; font-weight: 700; color: var(--blue); margin-bottom: 20px; letter-spacing: 0.1em; }
.card-title { font-size: 22px; font-weight: 700; margin-bottom: 12px; }
.card-desc { font-size: 15px; color: var(--ink-2); margin-bottom: 24px; flex: 1; }
.card-link { font-size: 14px; font-weight: 600; color: var(--blue); }
.card-link:hover { color: var(--blue-deep); }

/* ---------- 方法论（浅蓝大区块 · 对标腾讯官网） ---------- */

.method-band {
  background: linear-gradient(180deg, #F0F5FF 0%, #EAF1FF 100%);
  color: var(--ink);
  padding: 96px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.method-band .sec-eyebrow { color: var(--blue); }
.method-band .sec-title { color: var(--ink); }
.method-band .sec-desc { color: var(--ink-2); }
.method-band .tl-year { color: var(--blue); }
.method-band .tl-text { color: var(--ink-2); }
.method-band .tl-row { border-bottom-color: var(--line); }
.method-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 48px; }
.method-col {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 32px;
  box-shadow: 0 2px 8px rgba(29, 33, 41, 0.04);
  transition: all 0.25s ease;
}
.method-col:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-2px); }
.m-num { font-size: 13px; font-weight: 700; color: var(--blue); letter-spacing: 0.1em; margin-bottom: 16px; }
.m-title { font-size: 22px; font-weight: 700; color: var(--ink); margin-bottom: 12px; }
.m-desc { font-size: 15px; color: var(--ink-2); line-height: 1.8; }
.method-foot {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  gap: 14px;
}
.foot-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--blue); flex: 0 0 auto; }
.foot-text { font-size: 16px; color: var(--ink-2); }

/* ---------- 文章列表 ---------- */

.writing-head { display: flex; justify-content: space-between; align-items: flex-end; margin-bottom: 40px; }
.writing-all { font-size: 15px; font-weight: 600; color: var(--blue); }
.writing-all:hover { color: var(--blue-deep); }

.article-row {
  display: flex;
  align-items: center;
  gap: 36px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 32px;
  margin-bottom: 16px;
  transition: all 0.25s ease;
}
.article-row:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
  border-color: var(--blue);
}
.a-date { flex: 0 0 72px; font-size: 15px; font-weight: 600; color: var(--ink-3); }
.a-body { flex: 1; }
.a-title { display: block; font-size: 19px; font-weight: 700; margin-bottom: 6px; }
.a-desc { display: block; font-size: 14px; color: var(--ink-2); }
.a-tag {
  flex: 0 0 auto;
  font-size: 13px;
  font-weight: 600;
  color: var(--blue);
  background: var(--blue-light);
  border-radius: 4px;
  padding: 5px 12px;
}

/* ---------- FAQ ---------- */

.faq-list { max-width: 860px; margin: 0 auto; }
.faq-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 14px;
  overflow: hidden;
  transition: border-color 0.2s;
}
.faq-item:hover { border-color: var(--blue); }
.faq-item details summary {
  list-style: none;
  cursor: pointer;
  padding: 22px 28px;
  font-size: 17px;
  font-weight: 600;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.faq-item details summary::-webkit-details-marker { display: none; }
.faq-item details summary::after {
  content: "+";
  font-size: 22px;
  color: var(--blue);
  font-weight: 400;
  transition: transform 0.2s;
}
.faq-item details[open] summary::after { transform: rotate(45deg); }
.faq-a {
  padding: 0 28px 24px;
  font-size: 15px;
  color: var(--ink-2);
  line-height: 1.9;
  border-top: 1px solid var(--line);
  padding-top: 18px;
  margin: 0 0 0 0;
}
.faq-a strong { color: var(--ink); }

.faq-preview-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.faq-preview-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 26px;
  font-size: 16px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 14px;
  transition: all 0.2s;
}
.faq-preview-item:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-2px); }
.faq-preview-item .q-mark {
  flex: 0 0 28px;
  width: 28px;
  height: 28px;
  border-radius: 6px;
  background: var(--blue-light);
  color: var(--blue);
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
}

/* ---------- 联系 ---------- */

.contact-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: var(--shadow);
  display: flex;
  padding: 56px 64px;
  gap: 64px;
  align-items: center;
}
.contact-left { flex: 1; }
.contact-title { font-size: 36px; font-weight: 700; margin-bottom: 12px; }
.contact-sub { font-size: 16px; color: var(--ink-2); margin-bottom: 36px; }
.c-item { padding: 18px 0; border-bottom: 1px solid var(--line); }
.c-item:last-child { border-bottom: none; }
.c-label { display: block; font-size: 13px; color: var(--ink-3); margin-bottom: 4px; }
.c-value { display: block; font-size: 17px; font-weight: 600; }
.c-value small { display: block; font-size: 13px; font-weight: 400; color: var(--ink-3); margin-top: 2px; }
.qr-wrap { flex: 0 0 224px; text-align: center; }
.qr-box {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 12px;
  display: inline-block;
}
.qr-box img { width: 184px; height: 184px; object-fit: cover; border-radius: 4px; }
.qr-caption { font-size: 13px; color: var(--ink-3); margin-top: 12px; }

/* ---------- Footer ---------- */

.site-footer { background: #1D2129; color: rgba(255, 255, 255, 0.75); padding: 48px 0; font-size: 14px; }
.footer-slogan { font-size: 20px; font-weight: 600; color: #fff; margin-bottom: 24px; }
.footer-hairline { border: none; border-top: 1px solid rgba(255, 255, 255, 0.12); margin-bottom: 20px; }
.footer-bottom { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; }

/* ---------- 子页面 Hero ---------- */

.page-hero {
  background: linear-gradient(180deg, #F0F5FF 0%, #FFFFFF 100%);
  padding: 72px 0 56px;
}
.page-hero .tag { margin-bottom: 12px; }
.page-hero h1 { font-size: 44px; font-weight: 700; line-height: 1.3; margin-bottom: 14px; }
.page-hero p { font-size: 17px; color: var(--ink-2); max-width: 680px; }

/* ---------- 文章详情页 ---------- */

.article-head { padding: 72px 0 48px; border-bottom: 1px solid var(--line); }
.head-col { max-width: 800px; }
.head-meta { display: flex; gap: 16px; align-items: center; margin-bottom: 20px; }
.head-meta .tag { margin-bottom: 0; background: var(--blue-light); border-radius: 4px; padding: 4px 12px; }
.head-read { font-size: 13px; color: var(--ink-3); }
.head-title { font-size: 42px; font-weight: 700; line-height: 1.35; margin-bottom: 16px; }
.head-sub { font-size: 17px; color: var(--ink-2); margin-bottom: 28px; }
.head-author { display: flex; gap: 10px; align-items: center; font-size: 14px; color: var(--ink-3); }
.head-author .name { font-weight: 700; color: var(--ink); }

.article-body { padding: 56px 0 32px; }
.body-col { max-width: 800px; }
.article-text { font-size: 17px; line-height: 2; color: var(--ink-2); margin-bottom: 28px; }
.article-end-strong { font-size: 17px; font-weight: 600; color: var(--ink); margin-bottom: 28px; }

.section-head { display: flex; align-items: center; gap: 16px; margin: 48px 0 24px; }
.section-head .num { font-size: 15px; font-weight: 700; color: var(--blue); letter-spacing: 0.08em; }
.section-head .title { font-size: 24px; font-weight: 700; }

.quote-block {
  display: flex;
  gap: 18px;
  align-items: center;
  background: var(--blue-light);
  border-left: 4px solid var(--blue);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 22px 28px;
  margin: 32px 0;
}
.quote-text { font-size: 18px; font-weight: 600; color: var(--ink); }

.blue-band {
  background: linear-gradient(180deg, #F0F5FF 0%, #EAF1FF 100%);
  padding: 72px 0;
  text-align: center;
}
.blue-band .tag { color: var(--blue); }
.gold-band-title { font-size: 36px; font-weight: 700; margin-bottom: 12px; color: var(--ink); }
.gold-band-sub { font-size: 16px; color: var(--ink-2); }

.author-section { padding: 72px 0; background: var(--bg-gray); }
.author-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 40px 48px;
  display: flex;
  gap: 32px;
  align-items: center;
  box-shadow: var(--shadow);
}
.author-avatar { flex: 0 0 96px; }
.author-avatar img { width: 96px; height: 96px; border-radius: 50%; object-fit: cover; }
.author-info { flex: 1; }
.author-name-row { display: flex; align-items: baseline; gap: 14px; margin-bottom: 8px; flex-wrap: wrap; }
.author-name { font-size: 24px; font-weight: 700; }
.author-role { font-size: 14px; color: var(--blue); font-weight: 600; }
.author-bio { font-size: 15px; color: var(--ink-2); margin-bottom: 18px; max-width: 560px; }

.more-section { padding: 72px 0; }
.more-col { max-width: 860px; }
.more-tag { font-size: 13px; font-weight: 600; color: var(--blue); letter-spacing: 0.12em; margin-bottom: 10px; }
.more-title { font-size: 30px; font-weight: 700; margin-bottom: 32px; }
.more-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 14px;
  transition: all 0.2s;
  background: #fff;
}
.more-row:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-2px); }
.more-row .m-date { font-size: 13px; color: var(--ink-3); margin-bottom: 4px; }
.more-row .m-title { font-size: 18px; font-weight: 700; margin-bottom: 4px; }
.more-row .m-desc { font-size: 14px; color: var(--ink-2); }
.m-arrow { font-size: 20px; color: var(--blue); }

.cta-band {
  background: var(--bg-gray);
  padding: 72px 0;
}
.cta-band .container {
  display: flex;
  gap: 64px;
  align-items: center;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 48px 56px;
}
.cta-left { flex: 1; }
.cta-title { font-size: 30px; font-weight: 700; margin-bottom: 10px; }
.cta-sub { font-size: 15px; color: var(--ink-2); margin-bottom: 28px; }
.cta-contacts { display: flex; gap: 48px; flex-wrap: wrap; }
.cc-label { font-size: 13px; color: var(--ink-3); margin-bottom: 4px; }
.cc-value { font-size: 15px; font-weight: 600; }
.cta-qr { flex: 0 0 200px; text-align: center; }
.cta-qr .qr-box img { width: 160px; height: 160px; }

/* ---------- 内容页（关于/方法论） ---------- */

.prose { max-width: 800px; }
.prose h2 { font-size: 30px; font-weight: 700; margin: 56px 0 20px; }
.prose p { font-size: 16.5px; color: var(--ink-2); line-height: 2; margin-bottom: 24px; }
.prose .lead { font-size: 18px; color: var(--ink); font-weight: 500; }

.value-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin: 40px 0; }

/* ---------- 人系统标注（对齐讲课图 v4 · 功能红只标人系统） ---------- */

.card.card-human { border-color: rgba(213, 73, 65, 0.4); }
.card.card-human:hover { border-color: var(--red); }
.card-human-row { display: flex; align-items: center; gap: 10px; margin-bottom: 20px; }
.card-human-row .card-num { margin-bottom: 0; color: var(--red); }
.card-human-badge {
  font-size: 12px;
  font-weight: 700;
  color: var(--red);
  border: 1px solid rgba(213, 73, 65, 0.35);
  border-radius: 4px;
  padding: 2px 8px;
  letter-spacing: 0.08em;
}

/* 四大系统 pill 行（对齐讲课图 v4 底部） */
.system-pills { display: flex; align-items: center; gap: 12px; margin-top: 32px; flex-wrap: wrap; }
.sp {
  font-size: 13px;
  font-weight: 700;
  color: #fff;
  background: var(--blue);
  border-radius: 4px;
  padding: 4px 12px;
}
.sp.sp-human { background: var(--red); }
.sp-divider { width: 1px; height: 16px; background: var(--line); }
.sp-note { font-size: 14px; color: var(--ink-3); }

/* ---------- 首屏老板问句条 ---------- */
.hero-question {
  margin-top: 28px;
  padding: 18px 24px;
  background: var(--blue-bg);
  border-left: 3px solid var(--blue);
  border-radius: 6px;
  font-size: 15px;
  line-height: 1.8;
  text-align: left;
}
.hero-question .hq-q { color: var(--blue-deep); font-weight: 600; }
.hero-question .hq-a { color: var(--ink-2); margin-top: 4px; }
.hero-question .hq-a strong { color: var(--blue-deep); }

/* ---------- 三种型对比表 ---------- */
.table-wrap { overflow-x: auto; margin-top: 32px; }
.compare-table {
  width: 100%;
  min-width: 760px;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.compare-table th,
.compare-table td {
  padding: 18px 20px;
  text-align: left;
  font-size: 15px;
  line-height: 1.75;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
.compare-table thead th {
  background: var(--blue-bg);
  color: var(--blue-deep);
  font-size: 15px;
  font-weight: 700;
  border-bottom: 2px solid var(--blue);
}
.compare-table tbody tr:last-child td { border-bottom: none; }
.compare-table td.row-head {
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
  background: var(--bg-gray);
}
.compare-table .col-judgement { background: var(--blue-light); }
.compare-table .col-judgement strong { color: var(--blue-deep); }

/* ---------- 响应式 ---------- */

@media (max-width: 960px) {
  .container { padding: 0 20px; }
  .main-nav { display: none; }
  .hero { padding: 64px 0 56px; }
  .hero-title { font-size: 36px; }
  .hero-ctas { flex-direction: column; gap: 12px; margin-bottom: 40px; }
  .hero-stats { gap: 36px; flex-wrap: wrap; }
  .stat-num { font-size: 32px; }
  .section { padding: 56px 0; }
  .sec-title { font-size: 28px; }
  .about-wrap { flex-direction: column; gap: 32px; }
  .portrait-wrap { flex: none; width: 100%; max-width: 420px; }
  .cards-grid, .method-grid, .faq-preview-grid { grid-template-columns: 1fr; }
  .article-row { flex-direction: column; align-items: flex-start; gap: 10px; }
  .contact-card, .cta-band .container { flex-direction: column; padding: 36px 28px; gap: 32px; }
  .contact-title { font-size: 28px; }
  .head-title { font-size: 30px; }
  .article-head { padding: 48px 0 32px; }
  .article-body { padding: 36px 0; }
  .author-card { flex-direction: column; text-align: center; padding: 32px 24px; }
  .author-bio { max-width: none; }
  .more-row { flex-direction: column; align-items: flex-start; gap: 12px; }
  .cta-contacts { gap: 24px; }
  .page-hero h1 { font-size: 30px; }
  .value-grid { grid-template-columns: 1fr; }
}