/* ==========================================================================
   快连 KuaiLian · 全局样式
   设计方向：Editorial / 杂志感技术报告
   配色：墨黑 + 米白 + 亮橙 + 藏蓝
   ========================================================================== */

:root {
  --ink: #0E0F12;
  --ink-2: #1A1C1F;
  --paper: #F4F1EA;
  --paper-2: #FFFFFF;
  --paper-3: #EDE8DC;
  --line: #D8D2C4;
  --line-2: #BFB8A6;
  --accent: #FF5A1F;
  --accent-2: #FFB199;
  --link: #1536C5;
  --link-2: #0E2973;
  --good: #1E7E50;
  --muted: #5B5A55;
  --muted-2: #8A8780;

  --container: 1200px;
  --gap: 24px;
  --radius: 2px;

  --shadow-1: 0 1px 0 rgba(14, 15, 18, 0.06);
  --shadow-2: 0 6px 28px -10px rgba(14, 15, 18, 0.18);
  --shadow-3: 0 24px 60px -20px rgba(14, 15, 18, 0.22);

  --font-serif-cn: "Noto Serif SC", "Songti SC", "STSong", serif;
  --font-sans-cn: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", sans-serif;
  --font-serif-en: "Fraunces", "Times New Roman", serif;
  --font-sans-en: "DM Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Menlo, Consolas, monospace;

  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);
}

/* Reset */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans-cn), var(--font-sans-en);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg { max-width: 100%; display: block; }
a { color: var(--link); text-decoration: none; text-underline-offset: 2px; }
a:hover { color: var(--link-2); }
button { font: inherit; }
hr { border: none; border-top: 1px solid var(--line); margin: 32px 0; }

/* Layout */
.container { max-width: var(--container); margin: 0 auto; padding: 0 24px; }

/* Skip link */
.skip-link {
  position: absolute; top: -40px; left: 16px;
  background: var(--ink); color: var(--paper);
  padding: 8px 12px; border-radius: var(--radius);
  z-index: 999; transition: top .2s var(--ease);
}
.skip-link:focus { top: 16px; }

/* --------------------------------------------------------------------------
   Header / Navigation
-------------------------------------------------------------------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(244, 241, 234, 0.86);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .container {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px; gap: 24px;
}
.brand {
  display: inline-flex; align-items: baseline; gap: 8px;
  color: var(--ink); font-weight: 700; letter-spacing: 0;
  text-decoration: none;
  font-family: var(--font-serif-cn);
}
.brand .mark {
  font-size: 22px; line-height: 1;
}
.brand .name-en {
  font-family: var(--font-serif-en);
  font-size: 14px; color: var(--muted);
  letter-spacing: 0.06em; text-transform: uppercase;
}
.nav-toggle, .nav-toggle-label { display: none; }
.nav-links {
  display: flex; gap: 22px; align-items: center;
  list-style: none; padding: 0; margin: 0;
}
.nav-links a {
  color: var(--ink); text-decoration: none; font-size: 14px;
  padding: 6px 4px; border-bottom: 2px solid transparent;
  transition: border-color .15s var(--ease);
}
.nav-links a:hover { border-bottom-color: var(--accent); }
.nav-links a.active { border-bottom-color: var(--accent); }
.nav-links .pill {
  background: var(--ink); color: var(--paper);
  padding: 8px 14px; border-radius: 999px;
  font-weight: 600; font-size: 13px; letter-spacing: 0.04em;
  border: none;
}
.nav-links .pill:hover { background: var(--accent); color: var(--ink); }

/* Status strip (live feel) */
.status-strip {
  background: var(--ink); color: var(--paper);
  font-size: 12px; letter-spacing: 0.04em;
}
.status-strip .container {
  display: flex; gap: 18px; align-items: center; height: 36px;
  flex-wrap: wrap;
}
.status-strip .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: #4ADE80; box-shadow: 0 0 0 4px rgba(74, 222, 128, 0.16);
  display: inline-block; margin-right: 6px; vertical-align: middle;
}
.status-strip .sep { color: rgba(255,255,255,0.25); }
.status-strip time { font-variant-numeric: tabular-nums; }

/* --------------------------------------------------------------------------
   Hero
-------------------------------------------------------------------------- */
.hero { padding: 80px 0 56px; position: relative; overflow: hidden; }
.hero h1 {
  font-family: var(--font-serif-cn);
  font-weight: 800;
  font-size: clamp(34px, 5.4vw, 68px);
  line-height: 1.08; letter-spacing: -0.01em;
  margin: 0 0 18px;
}
.hero h1 em {
  font-style: normal; background: linear-gradient(180deg, transparent 65%, var(--accent-2) 65%);
  padding: 0 4px;
}
.hero .lede {
  font-size: 18px; color: var(--ink-2); max-width: 680px; margin: 0 0 28px;
}
.hero .meta { color: var(--muted); font-size: 13px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 18px; }
.hero-grid {
  display: grid; grid-template-columns: 1.25fr 0.95fr; gap: 48px; align-items: center;
}
.hero-grid .visual {
  border: 1px solid var(--line); border-radius: 4px;
  background: var(--paper-2); padding: 8px;
  box-shadow: var(--shadow-2);
}

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
}

/* --------------------------------------------------------------------------
   Buttons
-------------------------------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 22px; background: var(--ink); color: var(--paper);
  border: 1px solid var(--ink); border-radius: var(--radius);
  font-weight: 600; font-size: 14px; letter-spacing: 0.02em;
  text-decoration: none; cursor: pointer;
  transition: transform .15s var(--ease), background .15s var(--ease), color .15s var(--ease);
}
.btn:hover { background: var(--accent); color: var(--ink); border-color: var(--accent); }
.btn:active { transform: translateY(1px); }
.btn-outline { background: transparent; color: var(--ink); }
.btn-outline:hover { background: var(--ink); color: var(--paper); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.btn-ghost:hover { background: var(--ink); color: var(--paper); border-color: var(--ink); }

/* --------------------------------------------------------------------------
   Section primitives
-------------------------------------------------------------------------- */
section { padding: 56px 0; }
section + section { border-top: 1px dashed var(--line); }
.section-head {
  display: grid; grid-template-columns: 1.2fr 1fr; gap: 28px; align-items: end;
  margin-bottom: 32px;
}
.section-head .eyebrow {
  font-family: var(--font-mono); font-size: 12px;
  letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--accent); margin-bottom: 8px;
}
.section-head h2 {
  font-family: var(--font-serif-cn);
  font-size: clamp(26px, 3.4vw, 40px); line-height: 1.2;
  margin: 0; letter-spacing: -0.005em;
}
.section-head p { margin: 0; color: var(--muted); }
@media (max-width: 900px) { .section-head { grid-template-columns: 1fr; } }

/* Grid utilities */
.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 700px) {
  .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* --------------------------------------------------------------------------
   Cards
-------------------------------------------------------------------------- */
.card {
  background: var(--paper-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 24px;
  transition: transform .2s var(--ease), box-shadow .2s var(--ease), border-color .2s var(--ease);
}
.card:hover { transform: translateY(-2px); box-shadow: var(--shadow-2); border-color: var(--line-2); }
.card h3 {
  font-family: var(--font-serif-cn); font-weight: 700;
  font-size: 20px; margin: 0 0 8px;
}
.card p { margin: 0; color: var(--ink-2); }
.card .num {
  font-family: var(--font-serif-en); font-style: italic;
  color: var(--accent); font-size: 14px;
  letter-spacing: 0.06em;
}

.feature-card {
  background: var(--paper-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px;
  display: flex; flex-direction: column; gap: 12px; min-height: 220px;
  position: relative;
}
.feature-card .icon {
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--ink); color: var(--accent);
  display: inline-grid; place-items: center;
  font-family: var(--font-serif-en); font-style: italic; font-weight: 700;
}
.feature-card h3 {
  font-family: var(--font-serif-cn); font-size: 18px; margin: 4px 0 4px;
}
.feature-card p { color: var(--ink-2); margin: 0; font-size: 14.5px; }

/* --------------------------------------------------------------------------
   KPI data strip
-------------------------------------------------------------------------- */
.kpis {
  display: grid; grid-template-columns: repeat(6, 1fr);
  border-top: 1px solid var(--ink); border-bottom: 1px solid var(--ink);
  background: var(--paper-2);
}
.kpis .kpi {
  padding: 22px 18px;
  border-right: 1px solid var(--line);
}
.kpis .kpi:last-child { border-right: none; }
.kpis .kpi .val {
  font-family: var(--font-serif-en); font-style: italic;
  font-size: 32px; font-weight: 700; letter-spacing: -0.01em;
  display: block; line-height: 1.1;
}
.kpis .kpi .lab {
  display: block; margin-top: 6px;
  font-size: 12px; color: var(--muted); letter-spacing: 0.04em;
  text-transform: uppercase;
}
@media (max-width: 1024px) {
  .kpis { grid-template-columns: repeat(3, 1fr); }
  .kpis .kpi { border-right: none; border-bottom: 1px solid var(--line); }
}
@media (max-width: 520px) {
  .kpis { grid-template-columns: repeat(2, 1fr); }
}

/* --------------------------------------------------------------------------
   Steps (numbered, used multiple places)
-------------------------------------------------------------------------- */
.steps { counter-reset: step; padding: 0; margin: 0; list-style: none; }
.steps li {
  counter-increment: step;
  background: var(--paper-2); border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 24px 24px 88px; position: relative;
  margin-bottom: 12px;
}
.steps li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute; left: 24px; top: 24px;
  font-family: var(--font-serif-en); font-style: italic;
  font-weight: 700; font-size: 30px; color: var(--accent);
  background: var(--paper-3); width: 48px; height: 48px;
  border-radius: 50%; display: inline-grid; place-items: center;
}
.steps li h3 {
  font-family: var(--font-serif-cn); margin: 0 0 6px; font-size: 17px;
}
.steps li p { margin: 0; color: var(--ink-2); font-size: 14.5px; }

/* --------------------------------------------------------------------------
   Accordion (FAQ step-form)
-------------------------------------------------------------------------- */
.faq-group { border-top: 1px solid var(--ink); }
.faq details {
  border-bottom: 1px solid var(--line);
  padding: 18px 0;
}
.faq summary {
  cursor: pointer; list-style: none;
  display: flex; justify-content: space-between; align-items: center; gap: 16px;
  font-family: var(--font-serif-cn); font-weight: 600; font-size: 18px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; font-family: var(--font-serif-en);
  font-size: 24px; color: var(--accent); transition: transform .2s var(--ease);
}
.faq details[open] summary::after { content: "−"; }
.faq .faq-body {
  margin-top: 12px; color: var(--ink-2);
  background: var(--paper-2); border: 1px solid var(--line);
  padding: 18px 22px; border-radius: var(--radius);
}
.faq .faq-body ol { margin: 0; padding-left: 20px; }
.faq .faq-body ol li { margin: 6px 0; }
.faq .faq-body ol li strong { color: var(--accent); }

/* --------------------------------------------------------------------------
   Comparison table
-------------------------------------------------------------------------- */
.compare {
  width: 100%; border-collapse: collapse; background: var(--paper-2);
  border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden;
}
.compare th, .compare td {
  text-align: left; padding: 14px 16px;
  border-bottom: 1px solid var(--line); font-size: 14.5px;
}
.compare thead th {
  background: var(--ink); color: var(--paper); font-weight: 600;
  font-family: var(--font-sans-cn); letter-spacing: 0.02em;
  border-bottom-color: var(--ink);
}
.compare tbody tr:last-child td { border-bottom: none; }
.compare .yes { color: var(--good); font-weight: 600; }
.compare .no { color: var(--accent); font-weight: 600; }

/* --------------------------------------------------------------------------
   CTA band
-------------------------------------------------------------------------- */
.cta-band {
  background: var(--ink); color: var(--paper);
  padding: 64px 0;
}
.cta-band h2 {
  font-family: var(--font-serif-cn); font-size: clamp(24px, 3vw, 36px);
  margin: 0 0 8px;
}
.cta-band p { color: rgba(244,241,234,0.74); margin: 0 0 18px; }
.cta-band .btn { background: var(--accent); color: var(--ink); border-color: var(--accent); }
.cta-band .btn:hover { background: var(--paper); border-color: var(--paper); color: var(--ink); }

/* --------------------------------------------------------------------------
   Footer
-------------------------------------------------------------------------- */
.site-footer {
  background: var(--paper-3); padding: 56px 0 24px;
  border-top: 1px solid var(--line);
}
.footer-grid {
  display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 32px;
  margin-bottom: 32px;
}
.footer-grid h4 {
  font-family: var(--font-sans-cn); font-size: 13px;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--ink); margin: 0 0 14px;
}
.footer-grid ul { list-style: none; padding: 0; margin: 0; }
.footer-grid li { margin: 6px 0; }
.footer-grid a { color: var(--ink-2); font-size: 14px; }
.footer-grid a:hover { color: var(--accent); }
.footer-grid p { margin: 0; color: var(--muted); font-size: 13.5px; }
.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 16px;
  display: flex; justify-content: space-between; gap: 16px;
  font-size: 12px; color: var(--muted);
  flex-wrap: wrap;
}
@media (max-width: 800px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

/* --------------------------------------------------------------------------
   Breadcrumb
-------------------------------------------------------------------------- */
.breadcrumb {
  background: var(--paper-3); padding: 12px 0;
  border-bottom: 1px solid var(--line); font-size: 13px;
}
.breadcrumb .sep { margin: 0 8px; color: var(--muted-2); }
.breadcrumb .current { color: var(--muted); }

/* --------------------------------------------------------------------------
   Platform cards (download page)
-------------------------------------------------------------------------- */
.platforms { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.platform {
  background: var(--paper-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 24px;
  display: flex; flex-direction: column; gap: 12px;
}
.platform .pl-head {
  display: flex; align-items: baseline; justify-content: space-between;
}
.platform h2 {
  font-family: var(--font-serif-cn); margin: 0; font-size: 24px;
}
.platform .ver {
  font-family: var(--font-mono); font-size: 12px;
  background: var(--paper-3); padding: 2px 8px; border-radius: 999px; color: var(--muted);
}
.platform .size { color: var(--muted); margin: 0; font-size: 14px; }
.platform .sha {
  font-family: var(--font-mono); font-size: 12px;
  background: var(--ink); color: var(--paper);
  padding: 10px 12px; border-radius: var(--radius);
  word-break: break-all; line-height: 1.5;
}
@media (max-width: 700px) { .platforms { grid-template-columns: 1fr; } }

/* --------------------------------------------------------------------------
   Article / blog
-------------------------------------------------------------------------- */
.article {
  max-width: 760px; margin: 0 auto;
  font-size: 16.5px; line-height: 1.85;
}
.article h2 { font-family: var(--font-serif-cn); font-size: 28px; }
.article h3 { font-family: var(--font-serif-cn); font-size: 22px; margin-top: 28px; }
.article p { margin: 14px 0; }
.article blockquote {
  margin: 20px 0; padding: 14px 18px;
  background: var(--paper-3); border-left: 3px solid var(--accent);
  color: var(--ink-2); font-style: normal;
}
.article ul, .article ol { padding-left: 22px; }
.article .meta {
  color: var(--muted); font-size: 13px;
  display: flex; gap: 14px; flex-wrap: wrap;
  border-bottom: 1px solid var(--line); padding-bottom: 14px; margin-bottom: 22px;
}

.post-card {
  background: var(--paper-2); border: 1px solid var(--line);
  padding: 22px; border-radius: var(--radius);
  display: flex; flex-direction: column; gap: 10px;
}
.post-card .tag {
  font-family: var(--font-mono); font-size: 11px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent);
}
.post-card h3 {
  font-family: var(--font-serif-cn); margin: 0; font-size: 20px;
}
.post-card p { color: var(--ink-2); margin: 0; font-size: 14.5px; }
.post-card .foot {
  display: flex; justify-content: space-between; font-size: 12px; color: var(--muted);
  border-top: 1px dashed var(--line); padding-top: 10px; margin-top: 6px;
}

/* --------------------------------------------------------------------------
   Pricing
-------------------------------------------------------------------------- */
.tier {
  background: var(--paper-2); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px;
  display: flex; flex-direction: column; gap: 14px;
}
.tier.featured {
  background: var(--ink); color: var(--paper);
  border-color: var(--ink);
}
.tier.featured h3, .tier.featured .price { color: var(--paper); }
.tier h3 { font-family: var(--font-serif-cn); margin: 0; font-size: 22px; }
.tier .price {
  font-family: var(--font-serif-en); font-size: 36px; font-weight: 700;
}
.tier .price small { font-size: 14px; color: var(--muted); font-weight: 400; margin-left: 4px; }
.tier.featured .price small { color: rgba(244,241,234,0.6); }
.tier ul { padding-left: 18px; margin: 0; }
.tier li { margin: 6px 0; font-size: 14.5px; }
.tier .btn { margin-top: auto; }

/* --------------------------------------------------------------------------
   Node map
-------------------------------------------------------------------------- */
.node-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px;
}
.node-card {
  border: 1px solid var(--line); background: var(--paper-2);
  padding: 14px; border-radius: var(--radius); display: flex; flex-direction: column; gap: 6px;
}
.node-card .city { font-family: var(--font-serif-cn); font-weight: 600; }
.node-card .ms { font-family: var(--font-mono); font-size: 18px; }
.node-card .ms.good { color: var(--good); }
.node-card .ms.warn { color: #B45A00; }
.node-card .ms.bad { color: var(--accent); }
.node-card .flag { font-size: 13px; color: var(--muted); }
@media (max-width: 1024px) { .node-grid { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 700px) { .node-grid { grid-template-columns: repeat(2, 1fr); } }

/* --------------------------------------------------------------------------
   Forms
-------------------------------------------------------------------------- */
form .row { margin-bottom: 16px; display: flex; flex-direction: column; gap: 6px; }
form label { font-size: 13px; color: var(--muted); }
form input, form textarea, form select {
  font: inherit; padding: 12px 14px;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: var(--paper-2); color: var(--ink);
}
form textarea { min-height: 140px; resize: vertical; }
form input:focus, form textarea:focus, form select:focus {
  outline: 2px solid var(--accent); outline-offset: 0;
}

/* --------------------------------------------------------------------------
   Reveal animation
-------------------------------------------------------------------------- */
.reveal { opacity: 0; transform: translateY(12px); transition: opacity .5s var(--ease), transform .5s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* --------------------------------------------------------------------------
   Mobile nav
-------------------------------------------------------------------------- */
@media (max-width: 820px) {
  .nav-toggle-label {
    display: block; width: 28px; height: 24px; position: relative; cursor: pointer;
  }
  .nav-toggle-label span,
  .nav-toggle-label span::before,
  .nav-toggle-label span::after {
    content: ""; position: absolute; left: 0; right: 0; height: 2px; background: var(--ink);
    transition: transform .2s var(--ease);
  }
  .nav-toggle-label span { top: 11px; }
  .nav-toggle-label span::before { top: -8px; }
  .nav-toggle-label span::after { top: 8px; }
  .nav-toggle:checked ~ .nav-toggle-label span { background: transparent; }
  .nav-toggle:checked ~ .nav-toggle-label span::before { transform: translateY(8px) rotate(45deg); }
  .nav-toggle:checked ~ .nav-toggle-label span::after { transform: translateY(-8px) rotate(-45deg); }
  .nav-links {
    display: none; position: absolute; top: 64px; left: 0; right: 0;
    background: var(--paper); border-bottom: 1px solid var(--line);
    padding: 18px 24px; flex-direction: column; align-items: stretch; gap: 12px;
  }
  .nav-toggle:checked ~ .nav-links { display: flex; }
  .nav-links .pill { text-align: center; }
}

/* --------------------------------------------------------------------------
   Print
-------------------------------------------------------------------------- */
@media print {
  .site-header, .status-strip, .cta-band { display: none; }
  body { background: white; color: black; }
}