/* ============================================================
   儒钧科技 官网样式
   设计方向：Structured Confidence（结构化信赖感）× 教育科技绿
   ============================================================ */

/* ---------- 品牌色 tokens ---------- */
:root {
  --brand-50:  #ecfdf3;
  --brand-100: #d1fae5;
  --brand-200: #a7f3d0;
  --brand-300: #6ee7b7;
  --brand-400: #34d399;
  --brand-500: #10b981;
  --brand-600: #059669;
  --brand-700: #047857;
  --brand-800: #065f46;
  --brand-900: #064e3b;
  --brand-950: #022c22;

  --ink:    #0b1f18;
  --ink-2:  #22332c;
  --muted:  #576a61;
  --line:   #dde8e2;
  --surface:  #f5faf7;
  --surface-2:#eaf3ee;
  --white:  #ffffff;

  /* 语义层 */
  --c-primary:       var(--brand-700);
  --c-primary-hover: var(--brand-800);
  --c-on-primary:    #ffffff;
  --c-bg-dark:       var(--brand-950);
  --c-heading:       var(--ink);
  --c-body:          var(--ink-2);
  --c-muted:         var(--muted);
  --c-line:          var(--line);

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
               "Noto Sans SC", -apple-system, BlinkMacSystemFont,
               "Segoe UI", "Helvetica Neue", Arial, sans-serif;

  --container: 1160px;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 2px rgba(2, 44, 34, 0.06), 0 4px 16px rgba(2, 44, 34, 0.06);
  --shadow-md: 0 6px 24px rgba(2, 44, 34, 0.10);
  --shadow-lg: 0 18px 48px rgba(2, 44, 34, 0.16);

  --header-h: 72px;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  color: var(--c-body);
  background: var(--white);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; }
input, textarea { font-family: inherit; }
ul { list-style: none; padding: 0; }

:focus-visible {
  outline: 3px solid var(--brand-500);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- 通用布局 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

.section { padding: 100px 0; }
section[id] { scroll-margin-top: calc(var(--header-h) + 8px); }

.section-head {
  max-width: 720px;
  margin-bottom: 56px;
}
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }

.section-kicker {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--brand-700);
  background: var(--brand-50);
  border: 1px solid var(--brand-200);
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 18px;
}
h1, h2, h3 { color: var(--c-heading); line-height: 1.2; font-weight: 700; letter-spacing: 0.01em; }
.section-head h2 { font-size: clamp(28px, 4vw, 40px); margin-bottom: 16px; }
.section-sub { font-size: 17px; color: var(--c-muted); max-width: 60ch; }
.section-head.center .section-sub { margin: 0 auto; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 600;
  font-size: 15px;
  line-height: 1.2;
  transition: transform 0.18s ease, background-color 0.18s ease,
              color 0.18s ease, border-color 0.18s ease, box-shadow 0.18s ease;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: var(--c-primary);
  color: var(--c-on-primary);
}
.btn-primary:hover {
  background: var(--c-primary-hover);
  box-shadow: 0 8px 20px rgba(4, 120, 87, 0.28);
  transform: translateY(-1px);
}
.btn-ghost {
  background: transparent;
  color: inherit;
  border-color: rgba(11, 31, 24, 0.22);
}
.btn-ghost:hover { border-color: var(--c-heading); }
.btn-lg { padding: 15px 32px; font-size: 16px; }
.btn-block { width: 100%; }

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--header-h);
  z-index: 50;
  display: flex;
  align-items: center;
  transition: background-color 0.25s ease, box-shadow 0.25s ease;
  --nav-fg: #ffffff;
}
.site-header.is-scrolled {
  --nav-fg: var(--ink);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  box-shadow: 0 1px 0 var(--line);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand { display: flex; align-items: center; gap: 11px; color: var(--nav-fg); }
.brand-mark { border-radius: 9px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-text strong { font-size: 17px; font-weight: 700; }
.brand-text em {
  font-style: normal;
  font-size: 10px;
  letter-spacing: 0.16em;
  opacity: 0.66;
  font-weight: 600;
}

.site-nav { display: flex; gap: 34px; align-items: center; }
.site-nav a {
  font-size: 15px;
  font-weight: 500;
  color: var(--nav-fg);
  opacity: 0.88;
  padding: 8px 0;
  position: relative;
}
.site-nav a::after {
  content: "";
  position: absolute;
  left: 0; bottom: 2px;
  width: 100%; height: 2px;
  background: currentColor;
  border-radius: 2px;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.22s ease;
}
.site-nav a:hover { opacity: 1; }
.site-nav a:hover::after { transform: scaleX(1); }

.nav-actions { display: flex; align-items: center; gap: 14px; }
.nav-actions .btn-primary { background: var(--c-primary); }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px; height: 44px;
  padding: 10px;
  background: transparent;
  border: none;
  color: var(--nav-fg);
}
.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: currentColor;
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.2s ease;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-menu {
  display: none;
  position: absolute;
  top: var(--header-h);
  left: 0; right: 0;
  background: #fff;
  border-bottom: 1px solid var(--line);
  box-shadow: var(--shadow-md);
  padding: 16px 24px 24px;
  flex-direction: column;
  gap: 4px;
}
.mobile-menu.open { display: flex; }
.mobile-menu a {
  padding: 14px 8px;
  font-size: 16px;
  font-weight: 500;
  color: var(--ink);
  border-bottom: 1px solid var(--surface-2);
}
.mobile-menu a.btn { margin-top: 12px; justify-content: center; border: none; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: calc(var(--header-h) + 72px) 0 96px;
  background:
    radial-gradient(1200px 600px at 85% -10%, rgba(16, 185, 129, 0.28), transparent 60%),
    radial-gradient(900px 500px at -10% 110%, rgba(52, 211, 153, 0.18), transparent 55%),
    linear-gradient(180deg, var(--brand-950), #04372b);
  color: #e8f4ee;
  overflow: hidden;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(75% 70% at 50% 30%, #000 20%, transparent 100%);
  pointer-events: none;
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
}

.eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: #a7f3d0;
  border: 1px solid rgba(167, 243, 208, 0.35);
  background: rgba(6, 78, 59, 0.35);
  padding: 7px 15px;
  border-radius: 999px;
  margin-bottom: 24px;
}
.hero-title {
  font-size: clamp(36px, 5.4vw, 60px);
  color: #ffffff;
  letter-spacing: 0.01em;
  margin-bottom: 24px;
}
.hero-title span {
  background: linear-gradient(100deg, #6ee7b7, #34d399);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-lead {
  font-size: 18px;
  color: #cfe9dd;
  max-width: 52ch;
  margin-bottom: 34px;
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 44px; }
.hero-actions .btn-primary { background: var(--brand-500); }
.hero-actions .btn-primary:hover { background: var(--brand-400); }
.hero-actions .btn-ghost { color: #eafff5; border-color: rgba(234, 255, 245, 0.4); }
.hero-actions .btn-ghost:hover { border-color: #fff; background: rgba(255,255,255,0.06); }

.hero-stats { display: flex; gap: 40px; flex-wrap: wrap; }
.hero-stats div { display: flex; flex-direction: column; }
.hero-stats dt { order: 2; font-size: 13px; color: #93cdb6; letter-spacing: 0.04em; }
.hero-stats dd { order: 1; font-size: 30px; font-weight: 700; color: #fff; font-variant-numeric: tabular-nums; }

/* Hero 卡片视觉 */
.hero-visual { position: relative; }
.hero-card {
  background: #fff;
  color: var(--ink);
  border-radius: 18px;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  padding: 0;
}
.hc-head {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 15px 20px;
  border-bottom: 1px solid var(--surface-2);
  font-size: 14px;
  font-weight: 600;
}
.hc-dot { width: 9px; height: 9px; border-radius: 50%; background: var(--brand-500); }
.hc-tag {
  margin-left: auto;
  font-size: 12px;
  font-weight: 600;
  color: var(--brand-700);
  background: var(--brand-50);
  border: 1px solid var(--brand-200);
  padding: 3px 10px;
  border-radius: 999px;
}
.hc-body { padding: 20px; }
.hc-q { font-size: 15px; font-weight: 600; margin-bottom: 14px; }
.hc-answer { font-size: 15px; line-height: 1.9; margin-bottom: 14px; }
.hc-answer s { color: #c0392b; text-decoration-color: #e74c3c; }
.hc-result { font-weight: 700; color: var(--brand-700); }
.hc-check {
  display: inline-grid;
  place-items: center;
  width: 20px; height: 20px;
  background: var(--brand-500);
  color: #fff;
  border-radius: 50%;
  font-size: 12px;
  margin-left: 4px;
}
.hc-feedback {
  background: var(--brand-50);
  border: 1px solid var(--brand-100);
  border-radius: 12px;
  padding: 12px 14px;
  font-size: 13.5px;
  color: var(--ink-2);
}
.fb-label {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: var(--brand-700);
  letter-spacing: 0.06em;
  margin-bottom: 4px;
}
.hc-foot {
  display: flex;
  justify-content: space-between;
  padding: 12px 20px;
  background: var(--surface);
  border-top: 1px solid var(--surface-2);
  font-size: 12.5px;
  color: var(--muted);
  font-weight: 500;
}

.hero-chip {
  position: absolute;
  background: #fff;
  color: var(--ink);
  border-radius: 999px;
  padding: 9px 16px;
  font-size: 13px;
  font-weight: 600;
  box-shadow: var(--shadow-md);
}
.chip-a { top: -18px; right: 8%; }
.chip-b { bottom: -16px; left: 4%; }

/* ---------- About / 双轮卡片 ---------- */
.business-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}
.biz-card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 32px;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
  overflow: hidden;
}
.biz-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--brand-200);
}
.biz-icon {
  width: 54px; height: 54px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: var(--brand-600);
  color: #fff;
  margin-bottom: 22px;
}
.biz-no {
  position: absolute;
  top: 28px; right: 30px;
  font-size: 44px;
  font-weight: 800;
  color: var(--surface-2);
  line-height: 1;
}
.biz-card h3 { font-size: 22px; margin-bottom: 12px; }
.biz-card p { color: var(--c-muted); margin-bottom: 22px; }
.biz-link { font-weight: 600; color: var(--brand-700); }
.biz-link:hover { text-decoration: underline; }

/* ---------- 业务 section 背景差异 ---------- */
.business-edu { background: var(--surface); }
.business-emp { background: var(--white); }

/* 能力高亮：K12 全科 + 中英文作文 */
.cap-highlight {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin-bottom: 32px;
}
.cap-item {
  background: var(--white);
  border: 1px solid var(--line);
  border-left: 4px solid var(--brand-500);
  border-radius: var(--radius);
  padding: 20px 22px;
}
.cap-item h3 { font-size: 16px; margin-bottom: 6px; }
.cap-item p { font-size: 14px; color: var(--muted); }

/* 三大工作台 */
.workbench-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}
.workbench {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 26px;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}
.workbench:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--brand-300);
}
.wb-head {
  display: flex;
  align-items: center;
  gap: 14px;
  padding-bottom: 18px;
  margin-bottom: 4px;
  border-bottom: 1px solid var(--surface-2);
}
.wb-icon {
  width: 48px; height: 48px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  background: var(--brand-600);
  color: #fff;
  flex: none;
}
.wb-icon svg { width: 24px; height: 24px; }
.wb-title h3 { font-size: 19px; margin-bottom: 2px; }
.wb-tag { font-size: 12px; color: var(--muted); font-weight: 500; }
.wb-list li {
  position: relative;
  padding: 11px 0 11px 20px;
  font-size: 14.5px;
  color: var(--ink-2);
}
.wb-list li + li { border-top: 1px dashed var(--line); }
.wb-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 18px;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--brand-400);
}

/* 指标条 */
.metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--brand-950);
  color: #fff;
  border-radius: var(--radius);
  padding: 36px 28px;
  gap: 24px;
}
.metric { display: flex; flex-direction: column; gap: 6px; }
.metric strong {
  font-size: clamp(28px, 3vw, 38px);
  font-weight: 800;
  color: #6ee7b7;
  font-variant-numeric: tabular-nums;
  line-height: 1;
}
.metric span { font-size: 13px; color: #a9cbbc; line-height: 1.6; }

/* 数字员工 perks */
.emp-perks {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 44px;
}
.emp-perks span {
  font-size: 14px;
  font-weight: 600;
  color: var(--brand-700);
  background: var(--brand-50);
  border: 1px dashed var(--brand-300);
  padding: 10px 20px;
  border-radius: 999px;
}

/* ---------- 适用场景 ---------- */
.scenarios { background: var(--surface); }
.scenario-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 18px;
}
.scenario {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  text-align: center;
  padding: 28px 14px;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}
.scenario svg {
  width: 34px; height: 34px;
  color: var(--brand-600);
  display: inline-block;
}
.scenario:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-sm);
  border-color: var(--brand-300);
}
.scenario:hover svg { color: var(--brand-700); }
.scenario span { display: block; font-size: 15px; font-weight: 600; color: var(--ink); margin-top: 10px; }

/* ---------- 联系 ---------- */
.contact { background: linear-gradient(180deg, #fff, var(--surface)); }
.contact-grid {
  max-width: 640px;
  margin: 0 auto;
  text-align: center;
}
.contact-info h2 { font-size: clamp(28px, 4vw, 40px); margin: 6px 0 18px; }
.contact-info p { color: var(--c-muted); margin-bottom: 28px; }
.contact-list { max-width: 400px; margin: 0 auto; text-align: left; }
.contact-list li {
  display: flex;
  gap: 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
  align-items: baseline;
}
.contact-list li span {
  min-width: 48px;
  font-size: 13px;
  font-weight: 600;
  color: var(--muted);
  letter-spacing: 0.04em;
}
.contact-list a { font-weight: 600; color: var(--ink); }
.contact-list a:hover { color: var(--brand-700); }

.wechat-card {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 26px;
  padding: 15px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  text-align: left;
}
.wechat-qr {
  width: 88px;
  height: auto;
  border-radius: 10px;
  box-shadow: var(--shadow-sm);
  flex: none;
}
.wechat-text strong { display: block; font-size: 15px; color: var(--ink); margin-bottom: 3px; }
.wechat-text span { font-size: 13px; color: var(--muted); }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--brand-950);
  color: #9db8ab;
  padding: 40px 0;
}
.footer-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}
.footer-brand { display: flex; align-items: center; gap: 12px; font-size: 14px; }
.footer-brand img { border-radius: 6px; }
.footer-meta { display: flex; gap: 22px; font-size: 13px; flex-wrap: wrap; }
.footer-meta .icp { opacity: 0.66; }

/* ---------- 滚动 reveal（fail-open） ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.js [data-reveal].is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .js [data-reveal] { opacity: 1; transform: none; transition: none; }
  * { transition-duration: 0.001ms !important; animation-duration: 0.001ms !important; }
}

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .site-nav { display: none; }
  .nav-toggle { display: flex; }
  .nav-actions .btn-primary { display: none; }
  .hero-grid { grid-template-columns: 1fr; gap: 48px; }
  .hero-visual { max-width: 460px; margin: 0 auto; }
  .business-grid { grid-template-columns: 1fr; }
  .workbench-grid { grid-template-columns: 1fr; }
  .metrics { grid-template-columns: repeat(2, 1fr); }
  .scenario-grid { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 560px) {
  .section { padding: 68px 0; }
  .hero { padding-top: calc(var(--header-h) + 48px); padding-bottom: 72px; }
  .hero-stats { gap: 28px; }
  .cap-highlight { grid-template-columns: 1fr; }
  .metrics { grid-template-columns: 1fr 1fr; padding: 28px 22px; }
  .scenario-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-wrap { flex-direction: column; align-items: flex-start; }
}