/* ============================================================
   Launchlet — Landing Page
   Minimal SaaS design system (see landing/design-system.md)
   ============================================================ */

:root{
  --bg:     #ffffff;
  --ink:    #111315;
  --mut:    #8a8f94;
  --line:   #ececec;
  --accent: #3a5bff;

  --canvas: #fafafa;
  --ph-1:   #d7d7d7;
  --ph-2:   #dadada;
  --ph-3:   #e2e2e2;
  --ph-4:   #e4e4e4;

  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  --maxw: 1000px;
  --pad-x: 32px;
}

*{ box-sizing:border-box; }

html{ scroll-behavior:smooth; }

body{
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.6;
  letter-spacing:-.01em;
  -webkit-font-smoothing:antialiased;
}

a{ color:inherit; text-decoration:none; }

.wrap{
  max-width:var(--maxw);
  margin-inline:auto;
  padding-inline:var(--pad-x);
}

/* ---------- Typography helpers ---------- */
.eyebrow{
  font-size:13px;
  font-weight:400;
  letter-spacing:.04em;
  text-transform:uppercase;
  color:var(--mut);
  margin:0 0 18px;
}

/* ============ NAV ============ */
nav{
  position:sticky;
  top:0;
  z-index:50;
  background:rgba(255,255,255,.8);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  border-bottom:1px solid var(--line);
}
.navin{
  display:flex;
  align-items:center;
  gap:28px;
  height:64px;
}
.brand{
  display:flex;
  align-items:center;
  gap:9px;
}
.brand-icon{
  width:24px;
  height:24px;
  border-radius:6px;
  display:block;
}
.brand-name{
  font-size:17px;
  font-weight:600;
  letter-spacing:-.02em;
}
.navlinks{
  margin-left:auto;
  display:flex;
  gap:28px;
}
.navlinks a{
  font-size:14px;
  color:var(--mut);
  transition:color .2s;
}
.navlinks a:hover{ color:var(--ink); }

.lang{
  display:flex;
  align-items:center;
  gap:6px;
  font-size:13px;
}
.lang button{
  background:none;
  border:none;
  padding:0;
  cursor:pointer;
  color:var(--mut);
  font:inherit;
  transition:color .2s;
}
.lang button:hover{ color:var(--ink); }
.lang button.on{ color:var(--ink); font-weight:600; }
.lang .sep{ color:var(--line); }

/* ============ BUTTONS ============ */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  border-radius:8px;
  font-weight:500;
  transition:.2s;
  cursor:pointer;
  white-space:nowrap;
}
.btn-primary{ background:var(--ink); color:#fff; border:1px solid var(--ink); }
.btn-primary:hover{ opacity:.85; }
.btn-ghost{ background:transparent; color:var(--ink); border:1px solid var(--line); }
.btn-ghost:hover{ border-color:var(--ink); }

.btn-nav{ padding:8px 16px; font-size:14px; }
.btn-hero{ padding:11px 22px; font-size:15px; }
.btn-final{ padding:13px 28px; font-size:15px; }

/* ============ HERO ============ */
.hero{
  padding-top:clamp(90px,18vw,180px);
  padding-bottom:clamp(70px,12vw,120px);
  text-align:center;
}
.hero h1{
  font-size:clamp(40px,8vw,76px);
  font-weight:600;
  letter-spacing:-.035em;
  line-height:1.02;
  max-width:18ch;
  margin:0 auto 24px;
  white-space:pre-line;
}
html[lang="zh-CN"] .hero h1{
  letter-spacing:0;
  max-width:24ch;
}
.lede{
  font-size:clamp(17px,2.2vw,20px);
  color:var(--mut);
  max-width:46ch;
  margin:0 auto 36px;
}
.cta-row{
  display:flex;
  gap:12px;
  flex-wrap:wrap;
}
.hero .cta-row{ justify-content:center; }
.cta-row.center{ justify-content:center; }

/* ============ SHOT / PLACEHOLDER ============ */
.shot{ margin:0; }
.hero .shot{ margin-top:clamp(56px,9vw,90px); }

/* Placeholder mockup — swap the .ph div for an <img> when screenshots arrive */
.ph{
  position:relative;
  width:100%;
  aspect-ratio:640 / 400;
  border:1px solid var(--line);
  border-radius:14px;
  background:var(--canvas);
  overflow:hidden;
}
.ph-wide{ aspect-ratio:16 / 9; }
.ph-bar{
  position:absolute;
  top:0; left:0; right:0;
  height:34px;
  display:flex;
  align-items:center;
  gap:7px;
  padding-inline:16px;
  border-bottom:1px solid var(--line);
}
.ph-bar i{
  width:8px; height:8px;
  border-radius:50%;
  background:var(--ph-3);
  display:block;
}
.ph-label{
  position:absolute;
  inset:34px 0 0 0;
  display:flex;
  align-items:center;
  justify-content:center;
  color:var(--mut);
  font-size:13px;
  letter-spacing:-.005em;
}
/* Screenshot drop-in (when you replace .ph with <img class="shot-img">) */
.shot-img{
  display:block;
  width:100%;
  height:auto;
  border:1px solid var(--line);
  border-radius:14px;
  background:var(--canvas);
}
.cap{
  margin-top:14px;
  font-size:12px;
  color:var(--mut);
  text-align:center;
}

/* ============ STATS ============ */
.stats{
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:32px;
  padding-block:56px;
  border-top:1px solid var(--line);
  border-bottom:1px solid var(--line);
}
.stat .n{
  font-size:clamp(28px,4vw,38px);
  font-weight:600;
  letter-spacing:-.03em;
  line-height:1;
}
.stat .l{
  font-size:13px;
  color:var(--mut);
  margin-top:8px;
  max-width:22ch;
}

/* ============ FEATURES ============ */
.features{ }
.feature{
  display:grid;
  grid-template-columns:1fr 1.15fr;
  gap:clamp(40px,7vw,90px);
  align-items:center;
  padding-block:clamp(70px,12vw,130px);
}
.feature.flip .ftext{ order:2; }
.feature.flip .shot{ order:1; }

.feature h2{
  font-size:clamp(26px,3.6vw,38px);
  font-weight:600;
  letter-spacing:-.03em;
  line-height:1.1;
  margin:0 0 18px;
}
.fbody{
  font-size:clamp(16px,2vw,18px);
  color:var(--mut);
  max-width:42ch;
  margin:0;
}

/* ============ FINAL CTA ============ */
.final{
  padding-block:clamp(90px,16vw,170px);
  text-align:center;
  border-top:1px solid var(--line);
}
.final h2{
  font-size:clamp(32px,6vw,56px);
  font-weight:600;
  letter-spacing:-.035em;
  line-height:1.05;
  margin:0 auto 20px;
  max-width:18ch;
}
.final-sub{
  font-size:clamp(16px,2vw,18px);
  color:var(--mut);
  max-width:44ch;
  margin:0 auto 36px;
}

/* ============ LEGAL ============ */
.legal-main{
  max-width:820px;
  padding-top:clamp(72px,12vw,130px);
  padding-bottom:clamp(72px,12vw,120px);
}
.legal-hero{
  margin-bottom:clamp(42px,7vw,72px);
}
.legal-hero h1{
  font-size:clamp(42px,7vw,70px);
  font-weight:600;
  letter-spacing:-.035em;
  line-height:1.02;
  margin:0 0 22px;
}
.legal-subtitle{
  font-size:clamp(18px,2vw,21px);
  color:var(--mut);
  max-width:54ch;
  margin:0 0 14px;
}
.legal-meta{
  color:var(--mut);
  font-size:13px;
  margin:0;
}
.legal-section{
  padding:30px 0;
  border-top:1px solid var(--line);
}
.legal-section h2{
  font-size:clamp(22px,3vw,30px);
  font-weight:600;
  letter-spacing:-.025em;
  line-height:1.16;
  margin:0 0 12px;
}
.legal-section p{
  color:var(--mut);
  font-size:17px;
  line-height:1.72;
  margin:0;
}

/* ============ FOOTER ============ */
footer{
  border-top:1px solid var(--line);
}
.footin{
  display:flex;
  align-items:center;
  justify-content:space-between;
  flex-wrap:wrap;
  gap:20px;
  padding-top:48px;
  padding-bottom:24px;
}
.footbrand{
  display:flex;
  align-items:center;
  gap:9px;
}
.footbrand .dot{
  width:7px; height:7px;
  border-radius:50%;
  background:var(--accent);
  display:block;
}
.footlinks{
  display:flex;
  gap:24px;
}
.footlinks a{
  font-size:13px;
  color:var(--mut);
  transition:color .2s;
}
.footlinks a:hover{ color:var(--ink); }
.copy{
  font-size:12px;
  color:var(--mut);
  padding-bottom:48px;
}

/* ============ MOTION ============ */
.reveal{
  opacity:0;
  transform:translateY(16px);
  transition:opacity .7s ease, transform .7s ease;
}
.reveal.in{ opacity:1; transform:none; }

@media (prefers-reduced-motion:reduce){
  html{ scroll-behavior:auto; }
  .reveal{ opacity:1; transform:none; transition:none; }
}

/* ============ RESPONSIVE ============ */
@media (max-width:780px){
  :root{ --pad-x:24px; }
  .navin{ gap:16px; }
  .navlinks{ display:none; }
  .btn-nav{ padding:8px 14px; }
  html[lang="zh-CN"] .hero h1{
    font-size:26px;
    line-height:1.08;
    max-width:100%;
  }
  .feature{ grid-template-columns:1fr; gap:36px; }
  .feature.flip .ftext{ order:0; }
  .feature.flip .shot{ order:0; }
  .stats{ grid-template-columns:repeat(2,1fr); gap:28px; }
  .legal-hero h1{ letter-spacing:-.02em; }
}

@media (max-width:380px){
  :root{ --pad-x:16px; }
  .navin{ gap:12px; }
  .btn-nav{ padding:8px 12px; }
  html[lang="zh-CN"] .hero h1{ font-size:23px; }
}