/*
  qilaidav.com 全站样式。同源单文件，零外部请求（不引外部字体 / CDN）。
  引用处带 ?v=日期：nginx 对 .css 缓存 7 天，改完必须同步改各页的 v 参数，否则访客拿旧样式。

  视觉主线：「批注」。团队的卖点是替客户挑出系统里会出事的地方，
  所以唯一的强调元素是楷体红笔批注（.note），其余一律克制。
*/
:root {
  --paper:   #EDF0F3;
  --sheet:   #F7F8FA;
  --ink:     #15202B;
  --ink-2:   #4A5663;
  --ink-3:   #6E7A87;
  --rule:    #CBD2DA;
  --red:     #B3223D;
  --red-bg:  rgba(179, 34, 61, .07);
  --blue:    #1F4FB8;

  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
          "Microsoft YaHei", "Noto Sans CJK SC", "Helvetica Neue", Arial, sans-serif;
  --kai:  "Kaiti SC", "STKaiti", "KaiTi", "楷体", "AR PL UKai CN", serif;
  --measure: 680px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper:  #11171E;
    --sheet:  #171F28;
    --ink:    #E3E8EE;
    --ink-2:  #A3AEBA;
    --ink-3:  #7C8895;
    --rule:   #2B3643;
    --red:    #F07A8C;
    --red-bg: rgba(240, 122, 140, .09);
    --blue:   #8CAAF2;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 24px; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--blue); text-underline-offset: 3px; text-decoration-thickness: 1px; }
a:hover { text-decoration-thickness: 2px; }
a:focus-visible { outline: 2px solid var(--blue); outline-offset: 3px; border-radius: 2px; }
p { margin: 0 0 1em; }
h1, h2, h3 { color: var(--ink); margin: 0; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 24px; }
.col  { max-width: var(--measure); }

.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; background: var(--sheet); padding: 6px 10px; z-index: 9; }

/* ---------- 顶栏 ---------- */
.site-head { border-bottom: 1px solid var(--rule); }
.site-head .wrap {
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px; min-height: 60px; flex-wrap: wrap;
}
.brand { color: var(--ink); text-decoration: none; font-weight: 800; font-size: 19px; letter-spacing: -.01em; }
.brand::after { content: "。"; color: var(--red); font-family: var(--kai); }
.site-nav { display: flex; gap: 22px; flex-wrap: wrap; font-size: 15px; }
.site-nav a { color: var(--ink-2); text-decoration: none; }
.site-nav a:hover { color: var(--ink); }

/* ---------- 首屏 ---------- */
.hero { padding: 88px 0 56px; }
.hero h1 {
  font-size: clamp(36px, 6.4vw, 64px);
  line-height: 1.14;
  font-weight: 800;
  letter-spacing: -.02em;
  max-width: 13em;
  margin-bottom: 28px;
}
.lede { font-size: 19px; color: var(--ink-2); max-width: 36em; }
.lede strong { color: var(--ink); font-weight: 650; }

/* ---------- 批注：全站唯一的强调元素 ---------- */
.proof {
  margin: 48px 0 0;
  background: var(--sheet);
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 26px 28px 22px;
  max-width: 860px;
}
.proof-cap { font-size: 14px; color: var(--ink-3); margin: 0 0 14px; }
.proof ol { list-style: none; margin: 0; padding: 0; }
.proof li {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
  gap: 8px 32px;
  padding: 14px 0;
  border-top: 1px dashed var(--rule);
}
.proof li:first-child { border-top: 0; }
.claim { font-size: 15.5px; color: var(--ink-2); }
.claim s { text-decoration-color: var(--red); text-decoration-thickness: 2px; }
.note {
  font-family: var(--kai);
  color: var(--red);
  font-size: 18px;
  line-height: 1.55;
}
.proof-foot { margin: 14px 0 0; font-size: 14px; color: var(--ink-3); }

/* ---------- 通用分节 ---------- */
.section { padding: 72px 0; border-top: 1px solid var(--rule); }
.section > .wrap > h2,
.section-title {
  font-size: clamp(26px, 3.6vw, 34px);
  line-height: 1.25;
  font-weight: 800;
  letter-spacing: -.015em;
  margin-bottom: 14px;
}
.section-intro { color: var(--ink-2); max-width: 36em; margin-bottom: 40px; }

/* 做法：两列短论点 */
.tenets { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 36px 56px; }
.tenets h3 { font-size: 19px; font-weight: 700; margin-bottom: 8px; }
.tenets p { color: var(--ink-2); margin: 0; font-size: 16px; }

/* 旗舰系统：整行可点的条目，不做成卡片 */
.flagships { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--rule); }
.flagships li { border-bottom: 1px solid var(--rule); }
.flagships a {
  display: grid;
  grid-template-columns: minmax(0, 15em) minmax(0, 1fr) auto;
  gap: 8px 40px;
  align-items: baseline;
  padding: 28px 0;
  color: inherit;
  text-decoration: none;
}
.flagships h3 { font-size: 22px; font-weight: 750; line-height: 1.35; }
.flagships .kind { display: block; font-size: 14px; font-weight: 400; color: var(--ink-3); margin-top: 4px; }
.flagships p { margin: 0; color: var(--ink-2); font-size: 16px; }
.flagships .go { color: var(--blue); font-size: 15px; white-space: nowrap; }
.flagships a:hover h3,
.flagships a:hover .go { color: var(--blue); }
.flagships a:hover .go { text-decoration: underline; }
.flagships a:focus-visible { outline: 2px solid var(--blue); outline-offset: 4px; }

/* 更多系统：分组的紧凑清单 */
.catalog { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 44px 56px; }
.catalog h3 { font-size: 16px; font-weight: 700; color: var(--ink-3); margin-bottom: 12px; }
.catalog dl { margin: 0; }
.catalog dt { font-weight: 650; font-size: 17px; }
.catalog dd { margin: 2px 0 16px; color: var(--ink-2); font-size: 15.5px; line-height: 1.65; }

/* 合作方式 */
.modes { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 0; border-top: 2px solid var(--ink); }
.modes > div { padding: 22px 22px 6px 0; }
.modes > div + div { padding-left: 22px; border-left: 1px solid var(--rule); }
.modes h3 { font-size: 18px; font-weight: 700; margin-bottom: 6px; }
.modes p { color: var(--ink-2); font-size: 15.5px; }

/* 步骤（仅用于真有先后顺序的内容） */
.steps { counter-reset: s; list-style: none; margin: 0; padding: 0; max-width: 760px; }
.steps li { counter-increment: s; position: relative; padding: 0 0 26px 52px; }
.steps li::before {
  content: counter(s);
  position: absolute; left: 0; top: 0;
  width: 32px; height: 32px; border-radius: 50%;
  border: 1.5px solid var(--ink);
  display: grid; place-items: center;
  font-weight: 700; font-size: 15px;
}
.steps h3 { font-size: 18px; font-weight: 700; line-height: 32px; }
.steps p { color: var(--ink-2); margin: 2px 0 0; font-size: 16px; }

/* 产品页：能力清单 */
.features { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px 56px; }
.features h3 { font-size: 18px; font-weight: 700; margin-bottom: 6px; }
.features p { color: var(--ink-2); font-size: 16px; margin: 0; }
.features .note { display: block; font-size: 16px; margin-top: 8px; }

/* 联系 */
.contact { padding: 80px 0 88px; border-top: 1px solid var(--rule); }
.contact h2 { font-size: clamp(28px, 4.4vw, 42px); font-weight: 800; letter-spacing: -.02em; line-height: 1.2; margin-bottom: 16px; }
.contact p { color: var(--ink-2); max-width: 34em; }
.mail {
  display: inline-block;
  margin-top: 12px;
  font-size: clamp(20px, 3vw, 26px);
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 2px solid var(--red);
  padding-bottom: 2px;
}
.mail:hover { color: var(--red); }
.contact .hint { font-size: 15px; color: var(--ink-3); margin-top: 22px; }

/* 面包屑 */
.crumbs { font-size: 14px; color: var(--ink-3); padding-top: 28px; }
.crumbs a { color: var(--ink-3); }
.crumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; margin: 0; padding: 0; }
.crumbs li + li::before { content: "/"; margin-right: 6px; color: var(--rule); }
.page-hero { padding: 40px 0 56px; }
.page-hero h1 { font-size: clamp(32px, 5.2vw, 52px); line-height: 1.18; font-weight: 800; letter-spacing: -.02em; max-width: 15em; margin-bottom: 24px; }

/* 页脚 */
.site-foot { border-top: 1px solid var(--rule); padding: 28px 0 44px; font-size: 14px; color: var(--ink-3); }
.site-foot .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 10px 24px; }
.site-foot nav { display: flex; flex-wrap: wrap; gap: 8px 20px; }
.site-foot a { color: var(--ink-3); }

/* 唯一一段编排过的动效：首屏批注逐条落笔 */
@media (prefers-reduced-motion: no-preference) {
  .proof li .note { animation: ink .5s ease-out backwards; }
  .proof li:nth-child(1) .note { animation-delay: .35s; }
  .proof li:nth-child(2) .note { animation-delay: .75s; }
  .proof li:nth-child(3) .note { animation-delay: 1.15s; }
  .proof li .claim s { animation: strike .45s ease-out backwards; }
  .proof li:nth-child(1) .claim s { animation-delay: .2s; }
  .proof li:nth-child(2) .claim s { animation-delay: .6s; }
  .proof li:nth-child(3) .claim s { animation-delay: 1s; }
}
@keyframes ink { from { opacity: 0; transform: translateX(-6px); } to { opacity: 1; transform: none; } }
@keyframes strike { from { text-decoration-color: transparent; } }

@media (max-width: 860px) {
  .flagships a { grid-template-columns: 1fr; gap: 6px; padding: 24px 0; }
  .modes { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .modes > div:nth-child(3) { padding-left: 0; border-left: 0; }
  .modes > div:nth-child(n+3) { border-top: 1px solid var(--rule); }
}
@media (max-width: 640px) {
  body { font-size: 16px; }
  .wrap { padding: 0 16px; }
  .hero { padding: 52px 0 36px; }
  .lede { font-size: 17px; }
  .proof { padding: 18px 16px 16px; margin-top: 36px; }
  .proof li { grid-template-columns: 1fr; gap: 4px; }
  .section { padding: 52px 0; }
  .tenets, .catalog, .features { grid-template-columns: 1fr; gap: 28px; }
  .modes { grid-template-columns: 1fr; }
  .modes > div, .modes > div + div { padding: 18px 0 4px; border-left: 0; }
  .modes > div + div { border-top: 1px solid var(--rule); }
  .site-nav { gap: 16px; font-size: 14px; }
}

/* 标题下没有导语时，与正文网格拉开距离 */
.section-title + .features,
.section-title + .steps,
.section-title + .tenets,
.section-title + .modes { margin-top: 30px; }

/* 适合 / 不接：两列对照。不接那一列用批注红的细线标出——它是取舍，不是装饰 */
.fit { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 40px 56px; }
.fit h3 { font-size: 18px; font-weight: 700; margin-bottom: 10px; }
.fit ul { margin: 0; padding: 0 0 0 1.1em; color: var(--ink-2); font-size: 16px; }
.fit li { margin-bottom: 6px; }
.fit .no { border-left: 2px solid var(--red); padding-left: 20px; }
.fit .no h3 { color: var(--red); }

/* 常见问题：静态展开，问答全文都在 HTML 里，不依赖交互 */
.faq { margin: 0; max-width: 760px; }
.faq dt { font-weight: 700; font-size: 17.5px; margin-top: 26px; }
.faq dt:first-child { margin-top: 0; }
.faq dd { margin: 6px 0 0; color: var(--ink-2); font-size: 16px; }

/* 纯文字页（关于、隐私）：单栏阅读 */
/* .prose 与 .wrap 常在同一元素上：限宽只作用于子元素，容器本身保持 .wrap 的宽度与左边线 */
.prose > * { max-width: var(--measure); }
.prose h2 { font-size: 22px; font-weight: 750; margin: 40px 0 10px; }
.prose p, .prose li { color: var(--ink-2); }
.prose ul { padding-left: 1.2em; }

.updated { color: var(--ink-3); }

@media (max-width: 640px) {
  .fit { grid-template-columns: 1fr; gap: 28px; }
}