:root {
  --bg: #ffffff;
  --ink: #1f2230;
  --ink-soft: #4a4f63;
  --line: #e6e8f0;
  --indigo: #3949ab;
  --indigo-deep: #283593;
  --indigo-soft: #eef0fb;
  --warn-bg: #fff7e6;
  --warn-ink: #8a5a00;
  --ok: #1f8a54;
  --radius: 12px;
  --maxw: 1180px;
  font-synthesis: none;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--indigo); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255,255,255,0.92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--line);
}
.site-header .bar {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 14px 22px;
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
}
.brand {
  font-weight: 800;
  font-size: 19px;
  color: var(--indigo-deep);
  letter-spacing: .3px;
  white-space: nowrap;
}
.brand small {
  display: block;
  font-weight: 500;
  font-size: 12px;
  color: var(--ink-soft);
  letter-spacing: 0;
}
.topnav {
  display: flex;
  gap: 4px;
  margin-left: auto;
  flex-wrap: wrap;
}
.topnav a, .topnav span {
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 13.5px;
  color: var(--ink-soft);
}
.topnav a:hover { background: var(--indigo-soft); text-decoration: none; }
.topnav .active { background: var(--indigo); color: #fff; }
.topnav .coming { color: #b6bacb; cursor: default; }

/* ---------- layout ---------- */
.layout {
  max-width: var(--maxw);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 270px 1fr;
  gap: 34px;
  padding: 26px 22px 80px;
}

/* ---------- sidebar ---------- */
.sidebar {
  position: sticky;
  top: 78px;
  align-self: start;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 14px;
  background: #fcfcff;
  max-height: calc(100vh - 100px);
  overflow: auto;
}
.sidebar .sb-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--indigo-deep);
  padding: 4px 10px 10px;
  border-bottom: 1px dashed var(--line);
  margin-bottom: 8px;
}
.sidebar ol {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: ch;
}
.sidebar li a {
  display: block;
  padding: 8px 10px;
  border-radius: 8px;
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.45;
}
.sidebar li a:hover { background: var(--indigo-soft); text-decoration: none; }
.sidebar li a.active {
  background: var(--indigo);
  color: #fff;
  font-weight: 600;
}
.sidebar li a.active::before { content: ""; }
.sidebar .sb-note {
  margin-top: 12px;
  padding: 10px;
  font-size: 12px;
  color: #9aa0b5;
  border-top: 1px dashed var(--line);
}

/* ---------- content ---------- */
.content { min-width: 0; }
.article { max-width: 820px; }

h1 {
  font-size: 27px;
  line-height: 1.35;
  margin: 4px 0 18px;
  color: var(--indigo-deep);
}
h2 {
  font-size: 20px;
  margin: 34px 0 12px;
  padding-left: 11px;
  border-left: 4px solid var(--indigo);
}
h3 { font-size: 16.5px; margin: 24px 0 8px; color: var(--ink); }
p { margin: 12px 0; }
ul, ol { padding-left: 1.4em; }
li { margin: 6px 0; }
code {
  background: #f1f2f8;
  border-radius: 5px;
  padding: 1px 6px;
  font-size: 13.5px;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}
pre {
  background: #1f2230;
  color: #eef0fb;
  border-radius: 10px;
  padding: 14px 16px;
  overflow: auto;
  font-size: 13.5px;
  line-height: 1.6;
}
pre code { background: none; color: inherit; padding: 0; }
blockquote {
  border-left: 4px solid #c9cdf0;
  background: #f7f8ff;
  margin: 14px 0;
  padding: 10px 16px;
  color: var(--ink-soft);
}

table {
  border-collapse: collapse;
  width: 100%;
  margin: 16px 0;
  font-size: 14.5px;
}
th, td {
  border: 1px solid var(--line);
  padding: 9px 12px;
  text-align: left;
  vertical-align: top;
}
th { background: var(--indigo-soft); color: var(--indigo-deep); font-weight: 700; }

/* result card */
.result-card {
  background: linear-gradient(180deg, #f3f4ff, #eef0fb);
  border: 1px solid #d7dbf2;
  border-radius: var(--radius);
  padding: 18px 20px;
  margin: 0 0 18px;
}
.result-card .rc-label {
  display: inline-block;
  background: var(--indigo);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  padding: 3px 12px;
  border-radius: 999px;
}
.result-card p { margin: 8px 0 0; font-size: 16px; color: var(--indigo-deep); font-weight: 600; }
.badge-warn {
  display: inline-block;
  margin-top: 10px;
  background: var(--warn-bg);
  color: var(--warn-ink);
  font-size: 12.5px;
  padding: 5px 12px;
  border-radius: 999px;
  border: 1px solid #f3e0b0;
}

.screenshot-placeholder {
  border: 1.5px dashed #b9bee0;
  background: #fafbff;
  color: var(--ink-soft);
  border-radius: 10px;
  padding: 14px 16px;
  margin: 16px 0;
  font-size: 13.5px;
}

/* pager */
.pager {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-top: 46px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.pager a {
  flex: 1;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px 16px;
  font-size: 14px;
  color: var(--indigo-deep);
  background: #fff;
}
.pager a:hover { background: var(--indigo-soft); text-decoration: none; }
.pager .next { text-align: right; }
.pager .disabled {
  color: #b6bacb;
  border-style: dashed;
  pointer-events: none;
}

/* ---------- home ---------- */
.hero {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 46px 22px 10px;
}
.hero h1 {
  font-size: 34px;
  margin-bottom: 10px;
}
.hero .lead {
  font-size: 17px;
  color: var(--ink-soft);
  max-width: 720px;
}
.path-grid {
  max-width: var(--maxw);
  margin: 22px auto 0;
  padding: 0 22px 60px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
}
.path-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  background: #fff;
}
.path-card h3 { margin-top: 0; color: var(--indigo-deep); }
.path-card .tag {
  font-size: 12px;
  color: var(--ink-soft);
  background: var(--indigo-soft);
  padding: 3px 10px;
  border-radius: 999px;
}
.path-card.active { border-color: var(--indigo); box-shadow: 0 6px 22px rgba(57,73,171,.12); }
.path-card.coming { opacity: .62; }
.path-card ol { padding-left: 1.2em; margin: 12px 0 0; font-size: 14.5px; }
.path-card li { margin: 7px 0; }

.read-flow {
  max-width: 820px;
  margin: 10px auto 0;
  padding: 0 22px 70px;
}
.read-flow h2 { border: none; padding: 0; }
.flow-step {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: 14px 0;
  border-bottom: 1px dashed var(--line);
}
.flow-step .num {
  flex: none;
  width: 30px; height: 30px;
  border-radius: 50%;
  background: var(--indigo);
  color: #fff;
  font-weight: 700;
  display: grid; place-items: center;
  font-size: 14px;
}
.flow-step .body { flex: 1; }
.flow-step .body a { font-weight: 600; font-size: 15.5px; }

.note {
  max-width: 820px;
  margin: 0 auto 40px;
  padding: 14px 18px;
  background: #f7f8ff;
  border: 1px solid #d7dbf2;
  border-radius: 10px;
  font-size: 14px;
  color: var(--ink-soft);
}

@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; }
  .sidebar { position: static; max-height: none; }
}

/* ============ v2：循序渐进“带人”元素 ============ */

/* 痛点钩子卡 */
.pain-card {
  border-left: 4px solid var(--indigo);
  background: linear-gradient(180deg, #f5f6ff, #eef0fb);
  border-radius: 0 12px 12px 0;
  padding: 16px 20px;
  margin: 0 0 22px;
}
.pain-card .pc-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: var(--indigo-deep);
  background: #fff;
  border: 1px solid #c9cdf0;
  padding: 2px 10px;
  border-radius: 999px;
  margin-bottom: 8px;
}
.pain-card p { margin: 6px 0 0; color: var(--ink); }

/* 章节小节标签 */
.sect-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: #fff;
  background: var(--indigo);
  padding: 2px 10px;
  border-radius: 6px;
  margin-right: 8px;
  vertical-align: middle;
}

/* 可视化流程条 */
.flow {
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  gap: 6px;
  margin: 18px 0 22px;
}
.flow-seg {
  flex: 1 1 140px;
  background: var(--indigo-soft);
  border: 1px solid #c9cdf0;
  color: var(--indigo-deep);
  padding: 10px 12px;
  border-radius: 10px;
  font-size: 13.5px;
  line-height: 1.4;
  position: relative;
  text-align: center;
}
.flow-seg:not(:last-child)::after {
  content: "→";
  position: absolute;
  right: -10px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--indigo);
  font-weight: 800;
}
@media (max-width: 620px) {
  .flow-seg:not(:last-child)::after { content: "↓"; right: 50%; top: auto; bottom: -12px; transform: translateX(50%); }
}

/* 代码块标签 */
.code-cap {
  font-size: 12px;
  color: var(--ink-soft);
  background: #e9ebf7;
  border: 1px solid var(--line);
  border-bottom: none;
  display: inline-block;
  padding: 4px 12px;
  border-radius: 8px 8px 0 0;
  margin-top: 16px;
  margin-bottom: 0;
}
pre { margin-top: 0; border-top-left-radius: 0; }

/* 彩色提示卡：note / tip / warning / danger */
.callout {
  border-radius: 10px;
  padding: 12px 16px 12px 44px;
  margin: 16px 0;
  position: relative;
  font-size: 14.5px;
  line-height: 1.7;
}
.callout::before {
  position: absolute;
  left: 14px; top: 12px;
  font-size: 18px;
}
.callout.note { background: #eef4ff; border: 1px solid #cfe0ff; }
.callout.note::before { content: "💡"; }
.callout.tip { background: #eafaf1; border: 1px solid #bfe9cf; }
.callout.tip::before { content: "✅"; }
.callout.warning { background: var(--warn-bg); border: 1px solid #f3e0b0; }
.callout.warning::before { content: "⚠️"; }
.callout.danger { background: #fdecec; border: 1px solid #f4c4c4; }
.callout.danger::before { content: "⛔"; }

/* 验收清单 */
.checklist { list-style: none; padding-left: 0; margin: 14px 0; }
.checklist li {
  background: #f7f8ff;
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 10px 14px 10px 40px;
  margin: 8px 0;
  position: relative;
  font-size: 14.5px;
}
.checklist li::before {
  content: "☐";
  position: absolute;
  left: 14px; top: 9px;
  font-size: 17px;
  color: var(--indigo);
}

/* 误区块 */
.pitfall { border: 1px dashed #e0a3a3; background: #fdf3f3; border-radius: 10px; padding: 12px 16px; margin: 16px 0; }
.pitfall .pf-tag { font-size: 12px; font-weight: 700; color: #b3403f; }

/* 普通引用块（注意/提示等）基础样式 */
blockquote {
  margin: 16px 0;
  padding: 12px 16px;
  border-left: 4px solid var(--indigo, #5b5bf0);
  background: #f7f8ff;
  border-radius: 0 10px 10px 0;
  color: #444;
  font-size: 14.5px;
}
blockquote p { margin: 0; }

/* 截图占位 */
.screenshot-placeholder {
  margin: 18px 0;
  padding: 28px 18px;
  border: 2px dashed #b9bce8;
  border-radius: 12px;
  background: #fafaff;
  color: #6b6ea8;
  text-align: center;
  font-size: 14px;
}

/* ===== 蓝皮书富组件（IMA 白皮书扩展） ===== */
/* 心理旁白 */
.callout.psy { background:#eef4ff; border:1px solid #cfe0ff; color:#26324f; padding-left:44px; }
.callout.psy::before { content:"🤝"; }
/* 坑位提醒 */
.callout.pit { background:var(--warn-bg); border:1px solid #f3e0b0; color:var(--warn-ink); padding-left:44px; }
.callout.pit::before { content:"🕳️"; }
/* 真实案例 */
.callout.case { background:#eefaf1; border:1px solid #bfe9cc; color:#1f3d2b; padding-left:44px; }
.callout.case::before { content:"📌"; }
/* 编号步骤卡 */
.body ol.steps { list-style:none; counter-reset:step; padding-left:0; margin:18px 0; }
.body ol.steps > li {
  counter-increment:step; position:relative; padding:14px 16px 14px 56px;
  margin:10px 0; background:#fbfbff; border:1px solid var(--line);
  border-radius:12px; line-height:1.75; color:var(--ink);
}
.body ol.steps > li::before {
  content:counter(step); position:absolute; left:14px; top:13px;
  width:28px; height:28px; border-radius:50%; background:var(--indigo);
  color:#fff; font-weight:700; font-size:14px; display:flex;
  align-items:center; justify-content:center;
}
.body ol.steps > li strong { color:var(--indigo-deep); }
/* 规格表 */
.spec-wrap { margin:18px 0; overflow:hidden; border:1px solid var(--line); border-radius:12px; }
table.spec { border-collapse:collapse; width:100%; font-size:14.5px; background:#fff; }
table.spec th, table.spec td { border-bottom:1px solid var(--line); padding:11px 16px; text-align:left; vertical-align:top; }
table.spec thead th { background:var(--indigo-soft); color:var(--indigo-deep); font-weight:700; }
table.spec tbody tr td:first-child { background:#f7f8ff; font-weight:700; color:var(--indigo-deep); width:132px; white-space:nowrap; }
table.spec tbody tr:last-child td { border-bottom:none; }
/* 截图框 / 界面示意图 */
figure.shot { margin:20px 0; border:1px solid var(--line); border-radius:14px; overflow:hidden; background:#fff; box-shadow:0 6px 22px rgba(40,53,147,.07); }
figure.shot img { display:block; width:100%; height:auto; background:#f4f5fb; }
figure.shot figcaption { font-size:13px; color:var(--ink-soft); padding:10px 16px; background:#f7f8ff; border-top:1px solid var(--line); }
figure.shot figcaption b { color:var(--indigo-deep); }
figure.shot .shot-note { float:right; font-size:12px; color:#9aa0c0; }

/* 章节标题模块（对齐蓝皮书：篇标签眉标 + 第N章编号） */
.title-block { margin: 2px 0 18px; }
.title-series {
  font-size: 12.5px; font-weight: 700; letter-spacing: .04em;
  color: var(--indigo); background: var(--indigo-soft);
  display: inline-block; padding: 4px 10px; border-radius: 999px;
  margin-bottom: 12px;
}
.title-block h1 {
  font-size: 30px; line-height: 1.3; margin: 0; color: var(--indigo-deep);
  letter-spacing: -.01em; font-weight: 700;
}