/* ========== 设计系统（三页共用） ========== */
:root {
  --paper: #FAF9F7;        /* 纸白页面底 */
  --card: #FFFFFF;
  --ink: #20262B;          /* 墨色正文 */
  --ink-2: #5B6670;        /* 次级文字 */
  --line: #E6E2DB;         /* 分隔线 */
  --up: #C63A22;           /* 涨红：强调色 */
  --up-deep: #A82E19;
  --up-soft: #FBEFEC;
  --down: #1E7F5C;         /* 跌绿：成功/对照色 */
  --term: #101C24;         /* 终端盘面：代码块底 */
  --term-line: #22323D;
  --term-head: #8FA3AE;
  --cd-text: #D5DEE4;      /* 代码正文 */
  --cd-k: #66C7A9;         /* 关键字 */
  --cd-s: #E2A65E;         /* 字符串 */
  --cd-c: #64788A;         /* 注释 */
  --cd-f: #8FBFEA;         /* 函数/接口名 */
  --radius: 12px;
  --shadow: 0 1px 2px rgba(32,38,43,.05), 0 8px 24px -12px rgba(32,38,43,.18);
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
          "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
}
.wrap { max-width: 1060px; margin: 0 auto; padding: 0 24px; }
a { color: var(--up); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
:focus-visible { outline: 2px solid var(--up); outline-offset: 2px; border-radius: 2px; }
.mono { font-family: var(--mono); }

/* ========== 顶部导航 ========== */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: rgba(250,249,247,.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav-in { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.brand { display: flex; align-items: baseline; gap: 10px; color: var(--ink); font-weight: 600; }
.brand:hover { text-decoration: none; }
.brand-mark {
  font-family: var(--mono); font-size: 13px; font-weight: 700;
  color: #fff; background: var(--up);
  padding: 2px 7px; border-radius: 6px; letter-spacing: .5px;
  transform: translateY(-1px);
}
.brand-tag { font-family: var(--mono); font-size: 12px; color: var(--ink-2); letter-spacing: 1px; }
.anchors { display: flex; gap: 26px; }
.anchors a { color: var(--ink-2); font-size: 14.5px; }
.anchors a:hover { color: var(--up); text-decoration: none; }
.anchors a.on { color: var(--up); font-weight: 600; }

/* ========== Hero ========== */
.hero { border-bottom: 1px solid var(--line); background: linear-gradient(180deg, #FFFFFF 0%, var(--paper) 100%); }
.hero-in {
  display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px;
  align-items: center; padding-top: 72px; padding-bottom: 76px;
}
.hero h1 {
  font-size: 44px; line-height: 1.28; letter-spacing: .01em;
  font-weight: 700; margin: 0 0 18px;
}
.lede { color: var(--ink-2); font-size: 17px; margin: 0 0 26px; max-width: 30em; }
.gw-pill {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--mono); font-size: 14px;
  background: var(--up-soft); color: var(--up-deep);
  border: 1px solid #F0D8D2;
  padding: 8px 14px; border-radius: 999px;
}
.gw-pill .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--up); flex: none;
}

/* 教程页：本页内容跳转按钮 */
.toc { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 24px; }
.toc a {
  display: inline-flex; align-items: center; gap: 9px;
  font-size: 14.5px; font-weight: 600; color: var(--ink);
  background: var(--card); border: 1px solid var(--line);
  border-radius: 999px; padding: 7px 18px 7px 12px;
  box-shadow: var(--shadow);
  transition: color .15s, border-color .15s;
}
.toc a:hover { text-decoration: none; color: var(--up); border-color: var(--up); }
.toc .n {
  /* 与 .sec-idx「第 N 节」徽标同风格，区别于章节内步骤的实心圆序号 */
  flex: none; font-family: var(--mono); font-size: 12px; font-weight: 700;
  color: var(--up); border: 1px solid var(--up); border-radius: 6px;
  padding: 0 7px; line-height: 1.6;
}

/* 签名元素：仿终端 DataFrame 会话 */
.terminal {
  margin: 0; background: var(--term); border-radius: 14px;
  box-shadow: 0 24px 48px -24px rgba(16,28,36,.55);
  overflow: hidden; font-family: var(--mono); font-size: 13.5px;
}
.term-bar {
  display: flex; align-items: center; gap: 6px;
  padding: 11px 16px; border-bottom: 1px solid var(--term-line);
}
.term-bar i { width: 11px; height: 11px; border-radius: 50%; display: block; }
.term-bar i:nth-child(1) { background: #E5564A; }
.term-bar i:nth-child(2) { background: #E2A93C; }
.term-bar i:nth-child(3) { background: #57B45F; }
.term-bar span { margin-left: 8px; color: var(--term-head); font-size: 12px; letter-spacing: .5px; }
.terminal pre {
  margin: 0; padding: 18px 20px 22px; overflow-x: auto;
  color: var(--cd-text); line-height: 1.85;
}
.terminal .p { color: var(--cd-c); }            /* >>> 提示符 */
.terminal .hd { color: var(--term-head); }      /* 表头 */
.terminal .r { color: #F2846F; }                /* 涨 */
.terminal .g { color: #6FC79B; }                /* 跌 */

/* ========== 功能页页头带 ========== */
.page-head {
  background: linear-gradient(180deg, #FFFFFF 0%, var(--paper) 100%);
  border-bottom: 1px solid var(--line);
  padding: 52px 0 44px; text-align: center;
}
.page-head .crumb {
  font-family: var(--mono); font-size: 12.5px; letter-spacing: 3px;
  color: var(--up); margin: 0 0 10px;
}
.page-head h1 { font-size: 34px; line-height: 1.3; letter-spacing: .01em; margin: 0 0 10px; }
.page-head .page-lede { color: var(--ink-2); font-size: 15.5px; margin: 0 auto; max-width: 36em; }

/* ========== 章节 ========== */
main section { padding: 64px 0 8px; }
main section[id] { scroll-margin-top: 76px; }
main.single { min-height: 48vh; }
main.single section { padding-top: 44px; }
.page-narrow { max-width: 760px; margin-left: auto; margin-right: auto; }
.sec-head { display: flex; align-items: baseline; gap: 16px; margin-bottom: 26px; }
.sec-idx {
  font-family: var(--mono); font-size: 13px; color: var(--up);
  border: 1px solid var(--up); border-radius: 6px;
  padding: 1px 8px; letter-spacing: 1px; flex: none;
}
.sec-head h2 { font-size: 27px; margin: 0; letter-spacing: .01em; }
.sec-note { color: var(--ink-2); max-width: 44em; margin: 0 0 24px; }
.notice {
  display: block; max-width: 44em; margin: 0 0 26px;
  background: var(--up-soft); border: 1px solid #F0D8D2;
  border-left: 3px solid var(--up); border-radius: 8px;
  padding: 12px 16px; font-size: 14.5px; color: var(--ink);
}
.notice strong { color: var(--up-deep); margin-right: 6px; }
.notice code { white-space: nowrap; }
.hl {
  color: var(--up-deep); font-weight: 700;
  background: linear-gradient(transparent 62%, var(--up-soft) 62%);
  padding: 0 2px;
}
.step-h {
  display: flex; align-items: center; gap: 10px;
  font-size: 17.5px; font-weight: 700; margin: 38px 0 12px;
}
.sec-head + .step-h { margin-top: 0; }
.step-h .n {
  flex: none; width: 24px; height: 24px; border-radius: 50%;
  background: var(--up); color: #fff;
  font-family: var(--mono); font-size: 12.5px; font-weight: 700;
  display: inline-flex; align-items: center; justify-content: center;
}
.sec-note code, p code, li code, summary code {
  font-family: var(--mono); font-size: .92em;
  background: #F1EEE8; border: 1px solid var(--line);
  border-radius: 5px; padding: 1px 6px;
}

/* ========== 代码块（示例区通用） ========== */
.code {
  margin: 0 0 26px; background: var(--term);
  border-radius: var(--radius); overflow: hidden;
  box-shadow: 0 16px 32px -20px rgba(16,28,36,.5);
}
.code figcaption {
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 16px; border-bottom: 1px solid var(--term-line);
  color: var(--term-head); font-family: var(--mono); font-size: 12.5px;
  letter-spacing: 1px;
}
.code pre {
  margin: 0; padding: 18px 20px; overflow-x: auto;
  font-family: var(--mono); font-size: 13.5px; line-height: 1.85;
  color: var(--cd-text);
}
.code .k { color: var(--cd-k); }
.code .s { color: var(--cd-s); }
.code .c { color: var(--cd-c); }
.code .f { color: var(--cd-f); }
.copy {
  font-family: var(--mono); font-size: 12px;
  color: var(--cd-text); background: transparent;
  border: 1px solid var(--term-line); border-radius: 6px;
  padding: 4px 12px; cursor: pointer;
  transition: color .15s, border-color .15s, background .15s;
}
.copy:hover { color: #fff; border-color: var(--term-head); }
.copy.done { color: #6FC79B; border-color: #2E5C46; background: rgba(111,199,155,.08); }

/* ========== token 有效期查询 ========== */
.expiry-panel {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 28px;
}
.expiry-form { display: flex; gap: 12px; }
.expiry-input {
  flex: 1; min-width: 0;
  font-family: var(--mono); font-size: 14px;
  padding: 10px 14px; border: 1px solid var(--line); border-radius: 8px;
  background: var(--card); color: var(--ink);
}
.expiry-input::placeholder { color: var(--ink-2); opacity: .7; }
.expiry-btn {
  flex: none; font-family: var(--font); font-size: 15px; font-weight: 600;
  color: #fff; background: var(--up); border: none; border-radius: 8px;
  padding: 10px 24px; cursor: pointer;
  transition: background .15s;
}
.expiry-btn:hover { background: var(--up-deep); }
.expiry-btn:disabled { opacity: .55; cursor: wait; }
.expiry-result {
  margin: 18px 0 0;
  background: var(--paper); border: 1px solid var(--line);
  border-radius: 10px;
  padding: 18px 20px;
}
.expiry-result.err {
  background: var(--up-soft); border-color: #F0D8D2; box-shadow: none;
  color: var(--up-deep); font-size: 14.5px;
}
.expiry-rows { display: grid; grid-template-columns: auto 1fr; gap: 8px 20px; font-size: 15px; }
.expiry-rows dt { color: var(--ink-2); margin: 0; }
.expiry-rows dd { margin: 0; font-weight: 600; }
.expiry-pill {
  display: inline-block; font-size: 13px; font-weight: 700;
  padding: 1px 10px; border-radius: 999px;
}
.expiry-pill.ok { color: var(--down); background: #E9F4EF; border: 1px solid #CBE5DA; }
.expiry-pill.bad { color: var(--up-deep); background: var(--up-soft); border: 1px solid #F0D8D2; }
/* 未激活：中性提示色，不是故障 */
.expiry-pill.idle { color: #4A6785; background: #EDF3F9; border: 1px solid #D3E1EE; }

/* ========== 九折续买入口与弹窗 ========== */
.promo-row { text-align: center; margin: 22px 0 0; }
.promo-pill {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--font); font-size: 14.5px; font-weight: 600;
  color: #A85B12; background: #FDF4E8;
  border: 1px solid #F2DCC0; border-radius: 999px;
  padding: 8px 18px; cursor: pointer;
  transition: border-color .15s, box-shadow .15s;
}
.promo-pill:hover {
  border-color: #E8A659;
  box-shadow: 0 4px 14px -6px rgba(232,150,60,.45);
}
.promo-pill .badge {
  flex: none; font-size: 12.5px; font-weight: 700; color: #fff;
  background: linear-gradient(135deg, #FF9A3D, #F0741E);
  border-radius: 999px; padding: 1px 9px;
}
.promo-pill .arrow { font-family: var(--mono); transition: transform .15s; }
.promo-pill:hover .arrow { transform: translateX(3px); }

.modal-mask {
  position: fixed; inset: 0; z-index: 100;
  background: rgba(32,38,43,.55);
  display: flex; align-items: center; justify-content: center;
  padding: 24px;
}
.modal-mask[hidden] { display: none; }
.modal {
  position: relative; width: 100%; max-width: 400px;
  background: #fff; border-radius: 16px;
  padding: 26px 26px 20px; text-align: center;
  box-shadow: 0 24px 64px -16px rgba(16,28,36,.45);
}
.modal-close {
  position: absolute; top: -14px; right: -14px;
  width: 34px; height: 34px; border-radius: 50%;
  background: #fff; border: none; cursor: pointer;
  font-size: 19px; line-height: 1; color: var(--ink-2);
  box-shadow: 0 4px 12px rgba(32,38,43,.28);
}
.modal-close:hover { color: var(--ink); }
.modal-banner {
  background: linear-gradient(90deg, #FF7A45, #F5222D);
  color: #fff; font-size: 16.5px; font-weight: 700;
  border-radius: 10px; padding: 13px 16px;
}
.modal-sub { color: var(--ink); font-size: 14.5px; margin: 16px 0 12px; }
.modal-qr {
  background: #fff; border: 1px solid var(--line); border-radius: 12px;
  box-shadow: var(--shadow); padding: 18px;
}
.modal-qr img { width: 100%; max-width: 260px; display: block; margin: 0 auto; }
.modal-foot { color: var(--ink-2); font-size: 13.5px; margin: 14px 0 0; }

/* ========== 联系方式 ========== */
.contact-card {
  margin: 0 auto;
  max-width: 380px; text-align: center;
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 28px 28px 22px;
}
.contact-card img {
  width: 100%; max-width: 280px; display: block; margin: 0 auto;
  border-radius: 8px;
}
.contact-card .tip { color: var(--ink-2); font-size: 14.5px; margin: 14px 0 0; }

/* ========== FAQ ========== */
.faq {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); margin-bottom: 12px;
  box-shadow: var(--shadow);
}
.faq summary {
  cursor: pointer; padding: 16px 20px; font-weight: 600; font-size: 15.5px;
  list-style: none; display: flex; align-items: center; gap: 12px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::before {
  content: "问"; flex: none;
  font-family: var(--mono); font-size: 12px;
  color: var(--up); border: 1px solid var(--up);
  border-radius: 6px; padding: 0 6px;
}
.faq[open] summary { border-bottom: 1px dashed var(--line); }
.faq .a { padding: 14px 20px 18px 52px; color: var(--ink-2); font-size: 14.5px; }
.faq .a p { margin: 0 0 8px; }
.faq .a p:last-child { margin-bottom: 0; }

/* ========== 页脚 ========== */
footer {
  margin-top: 72px; border-top: 1px solid var(--line);
  padding: 28px 0 40px; color: var(--ink-2); font-size: 13.5px;
}
footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }

/* ========== 响应式 ========== */
@media (max-width: 900px) {
  .hero-in { grid-template-columns: 1fr; gap: 36px; padding-top: 48px; padding-bottom: 52px; }
  .hero h1 { font-size: 36px; }
}
@media (max-width: 640px) {
  .anchors { gap: 14px; }
  .anchors a { font-size: 13.5px; }
  .hero h1 { font-size: 31px; }
  main section { padding-top: 48px; }
  .sec-head { flex-direction: column; gap: 8px; align-items: flex-start; }
  .page-head { padding: 40px 0 34px; }
  .page-head h1 { font-size: 27px; }
  .expiry-panel { padding: 20px; }
  .expiry-form { flex-direction: column; }
}