/* ===== Design Tokens ===== */
:root {
  --bg: #FBF7F3;
  --bg-alt: #F4ECE4;
  --ink: #2C2622;
  --ink-soft: #6B5F57;
  --accent: #B07D56;
  --accent-deep: #8A5A3B;
  --line: #E7DCD2;
  --white: #FFFFFF;
  --shadow: 0 18px 50px rgba(60, 40, 25, 0.08);
  --radius: 16px;
  --maxw: 1180px;
  --serif: "Noto Serif SC", "Songti SC", "SimSun", serif;
  --sans: "Noto Sans SC", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
h1, h2, h3 { font-family: var(--serif); font-weight: 600; line-height: 1.3; margin: 0; }
.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(251, 247, 243, 0.86);
  backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-wrap { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; flex-direction: column; line-height: 1; }
.brand-cn { font-family: var(--serif); font-size: 22px; font-weight: 700; letter-spacing: 2px; color: var(--ink); }
.brand-en { font-size: 10px; letter-spacing: 4px; color: var(--accent); margin-top: 3px; }
.nav { display: flex; align-items: center; gap: 30px; }
.nav a { font-size: 15px; color: var(--ink-soft); transition: color .2s; }
.nav a:hover { color: var(--accent-deep); }
.nav-cta {
  background: var(--ink); color: var(--white) !important;
  padding: 9px 20px; border-radius: 999px; font-size: 14px !important;
}
.nav-cta:hover { background: var(--accent-deep); }
.nav-right { display: flex; align-items: center; gap: 14px; }
.lang-toggle {
  border: 1px solid var(--line); background: var(--white);
  color: var(--ink); font-family: var(--sans); font-size: 13px; letter-spacing: 1px;
  padding: 8px 14px; border-radius: 999px; cursor: pointer; transition: all .2s;
}
.lang-toggle:hover { border-color: var(--accent); color: var(--accent-deep); }
.menu-btn { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px; }
.menu-btn span { width: 24px; height: 2px; background: var(--ink); border-radius: 2px; transition: .25s; }

/* ===== Buttons ===== */
.btn {
  display: inline-block; padding: 14px 34px; border-radius: 999px;
  font-size: 15px; font-weight: 500; letter-spacing: 1px; cursor: pointer;
  transition: transform .15s, box-shadow .25s, background .25s; border: 1px solid transparent;
}
.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 10px 26px rgba(176,125,86,.32); }
.btn-primary:hover { background: var(--accent-deep); transform: translateY(-2px); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--ink); }
.btn-ghost:hover { background: var(--ink); color: #fff; }
.btn-block { width: 100%; padding: 16px; font-size: 16px; }

/* ===== Hero ===== */
.hero { position: relative; overflow: hidden; padding: 120px 0 130px; }
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(120% 90% at 80% 0%, rgba(176,125,86,.16), transparent 55%),
    radial-gradient(90% 70% at 10% 100%, rgba(138,90,59,.12), transparent 60%),
    linear-gradient(180deg, #FCF9F5 0%, #F6EEE6 100%);
}
.hero-bg::after {
  content: ""; position: absolute; inset: 0;
  background-image: radial-gradient(rgba(176,125,86,.10) 1px, transparent 1.4px);
  background-size: 26px 26px; opacity: .5;
}
.hero-inner { position: relative; text-align: center; }
.hero-eyebrow { letter-spacing: 4px; font-size: 13px; color: var(--accent-deep); margin: 0 0 18px; text-transform: uppercase; }
.hero-title { font-size: clamp(32px, 5vw, 52px); letter-spacing: 1px; max-width: 16em; margin: 0 auto; }
.hero-subtitle { font-size: clamp(16px, 2.2vw, 20px); color: var(--ink-soft); margin: 22px auto 38px; max-width: 32em; }
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-note { margin-top: 26px; font-size: 13px; color: #A99A8C; }

/* ===== Section ===== */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { max-width: 720px; margin: 0 auto 56px; text-align: center; }
.section-kicker { display: inline-block; font-size: 13px; letter-spacing: 3px; color: var(--accent-deep); text-transform: uppercase; margin-bottom: 14px; }
.section-title { font-size: clamp(26px, 3.4vw, 36px); }
.section-lead { margin-top: 16px; color: var(--ink-soft); font-size: 16px; }

/* ===== About ===== */
.about-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.about-card {
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px 24px; box-shadow: var(--shadow);
}
.about-card h3 { font-size: 19px; margin-bottom: 12px; color: var(--accent-deep); }
.about-card p { margin: 0; font-size: 14.5px; color: var(--ink-soft); }

.timeline { margin-top: 64px; }
.timeline-title { text-align: center; font-size: 24px; margin-bottom: 34px; }
.timeline-list { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; position: relative; }
.timeline-list::before { content: ""; position: absolute; top: 14px; left: 6%; right: 6%; height: 2px; background: linear-gradient(90deg, var(--accent), var(--line)); }
.timeline-list li { text-align: center; position: relative; padding-top: 40px; }
.timeline-list li::before { content: ""; position: absolute; top: 7px; left: 50%; transform: translateX(-50%); width: 16px; height: 16px; border-radius: 50%; background: var(--accent); border: 3px solid var(--bg); box-shadow: 0 0 0 2px var(--accent); }
.tl-year { display: block; font-family: var(--serif); font-size: 20px; color: var(--accent-deep); font-weight: 700; }
.tl-text { display: block; font-size: 14px; color: var(--ink-soft); margin-top: 6px; }
.about-foot { text-align: center; margin-top: 48px; font-size: 15px; color: var(--ink-soft); }

/* ===== Advantages ===== */
.adv-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.adv-card {
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 26px; transition: transform .2s, box-shadow .25s; position: relative; overflow: hidden;
}
.adv-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.adv-no { font-family: var(--serif); font-size: 30px; color: var(--line); font-weight: 700; }
.adv-card h3 { font-size: 18px; margin: 10px 0 10px; }
.adv-card p { margin: 0; font-size: 14px; color: var(--ink-soft); }

/* ===== Models ===== */
.model-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.model-card {
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px 30px; box-shadow: var(--shadow); display: flex; flex-direction: column;
}
.model-tag { font-size: 12px; letter-spacing: 2px; color: var(--accent); text-transform: uppercase; }
.model-card h3 { font-size: 23px; margin: 12px 0 14px; }
.model-card > p { color: var(--ink-soft); font-size: 14.5px; margin: 0 0 18px; }
.model-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.model-list li { padding: 12px 0; font-size: 14px; color: var(--ink); border-bottom: 1px solid var(--line); }
.model-list li::before { content: "—"; color: var(--accent); margin-right: 10px; }

/* ===== Process ===== */
.process-list { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(6, 1fr); gap: 18px; counter-reset: step; }
.process-list li { text-align: center; position: relative; padding-top: 8px; }
.step-no {
  display: flex; align-items: center; justify-content: center; width: 52px; height: 52px;
  margin: 0 auto 16px; border-radius: 50%; background: var(--white); border: 2px solid var(--accent);
  color: var(--accent-deep); font-family: var(--serif); font-size: 22px; font-weight: 700; box-shadow: var(--shadow);
}
.process-list li:not(:last-child)::after {
  content: ""; position: absolute; top: 34px; left: 56%; right: -10%; height: 2px;
  background: repeating-linear-gradient(90deg, var(--accent) 0 6px, transparent 6px 12px); opacity: .5;
}
.process-list h3 { font-size: 17px; margin-bottom: 8px; }
.process-list p { font-size: 13px; color: var(--ink-soft); margin: 0; }

/* ===== News ===== */
.news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.news-card { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 30px 28px; box-shadow: var(--shadow); display: flex; flex-direction: column; }
.news-cat { font-size: 12px; letter-spacing: 1px; color: var(--accent); text-transform: uppercase; }
.news-card h3 { font-size: 19px; margin: 12px 0 12px; line-height: 1.45; }
.news-card p { font-size: 14px; color: var(--ink-soft); margin: 0 0 18px; flex: 1; }
.news-date { font-size: 12px; color: #A99A8C; letter-spacing: 1px; }

/* ===== Contact ===== */
.contact-wrap { display: grid; grid-template-columns: 0.85fr 1.15fr; gap: 44px; align-items: start; }
.contact-info { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 36px 32px; box-shadow: var(--shadow); }
.contact-info h3 { font-size: 18px; margin-bottom: 12px; }
.contact-phone { display: inline-block; font-family: var(--serif); font-size: 30px; color: var(--accent-deep); font-weight: 700; letter-spacing: 1px; }
.contact-tip { font-size: 13.5px; color: var(--ink-soft); margin: 10px 0 18px; }
.contact-points { list-style: none; margin: 0; padding: 0; }
.contact-points li { font-size: 14px; color: var(--ink); padding: 10px 0; border-top: 1px solid var(--line); }
.contact-points li::before { content: "✦"; color: var(--accent); margin-right: 10px; }

.contact-form { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 36px 32px; box-shadow: var(--shadow); }
.field { margin-bottom: 18px; display: flex; flex-direction: column; }
.field-full { grid-column: 1 / -1; }
.contact-form .field { display: block; }
.contact-form .field label { display: block; font-size: 14px; margin-bottom: 8px; color: var(--ink); font-weight: 500; }
.contact-form input, .contact-form select, .contact-form textarea {
  width: 100%; padding: 13px 15px; border: 1px solid var(--line); border-radius: 10px;
  font-family: var(--sans); font-size: 15px; color: var(--ink); background: #FCFAF7; transition: border .2s, box-shadow .2s;
}
.contact-form textarea { resize: vertical; }
.contact-form input:focus, .contact-form select:focus, .contact-form textarea:focus {
  outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(176,125,86,.15);
}
.field-error { display: none; color: #C0392B; font-size: 12.5px; margin-top: 6px; }
.field.invalid input, .field.invalid select { border-color: #C0392B; }
.field.invalid .field-error { display: block; }
.privacy { font-size: 12.5px; color: #A99A8C; line-height: 1.7; margin: 6px 0 20px; padding: 14px 16px; background: var(--bg-alt); border-radius: 10px; }
.form-status { font-size: 14px; margin: 14px 0 0; min-height: 20px; }
.form-status.ok { color: #2E7D52; font-weight: 500; }

/* ===== Footer ===== */
.site-footer { background: var(--ink); color: #E9DED4; padding: 48px 0; }
.footer-wrap { text-align: center; max-width: 760px; }
.footer-brand { display: flex; flex-direction: column; align-items: center; margin-bottom: 14px; }
.footer-brand .brand-cn { color: #fff; font-size: 22px; letter-spacing: 2px; }
.footer-brand .brand-en { color: var(--accent); }
.footer-copy { font-size: 13px; color: #B7A99C; margin: 0 0 14px; }
.footer-disclaimer { font-size: 12.5px; color: #9C8E80; line-height: 1.8; margin: 0; }

/* ===== Responsive ===== */
@media (max-width: 980px) {
  .about-grid, .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .timeline-list { grid-template-columns: repeat(2, 1fr); gap: 36px 20px; }
  .timeline-list::before { display: none; }
  .model-grid, .news-grid { grid-template-columns: 1fr; }
  .process-list { grid-template-columns: repeat(2, 1fr); gap: 30px 18px; }
  .process-list li:not(:last-child)::after { display: none; }
  .contact-wrap { grid-template-columns: 1fr; gap: 28px; }
}
@media (max-width: 640px) {
  .nav { position: fixed; top: 72px; left: 0; right: 0; background: var(--bg); flex-direction: column; gap: 0; padding: 10px 24px 22px; border-bottom: 1px solid var(--line); transform: translateY(-130%); transition: transform .3s; box-shadow: var(--shadow); }
  .nav.open { transform: translateY(0); }
  .nav a { padding: 14px 0; width: 100%; border-bottom: 1px solid var(--line); }
  .nav-cta { text-align: center; margin-top: 12px; }
  .menu-btn { display: flex; }
  .about-grid, .adv-grid, .timeline-list { grid-template-columns: 1fr; }
  .section { padding: 64px 0; }
  .hero { padding: 86px 0 92px; }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}