/* ==========================================================
   特教AI助手 官网 · 浅蓝主题
   ========================================================== */

:root {
  --blue-900: #0a3357;
  --blue-800: #0f4573;
  --blue-700: #1565a8;
  --blue-600: #1b7ac9;
  --blue-500: #3d9ae4;
  --blue-400: #6fbcf4;
  --blue-300: #a4d7f8;
  --blue-200: #cbe7fb;
  --blue-100: #e3f1fd;
  --blue-50: #f2f8fe;
  --ice: #f7fbff;

  --ink: #12324f;
  --ink-2: #3f5c76;
  --ink-3: #728ea6;

  --white: #ffffff;
  --line: #dcebf8;

  --radius-l: 22px;
  --radius: 16px;
  --radius-s: 10px;

  --shadow-s: 0 2px 10px rgba(21, 101, 168, 0.06);
  --shadow: 0 10px 30px rgba(21, 101, 168, 0.09);
  --shadow-l: 0 22px 50px rgba(21, 101, 168, 0.14);

  --max: 1160px;
  --nav-h: 68px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 88px; }

body {
  margin: 0;
  font-family: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei",
    "Hiragino Sans GB", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--white);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  font-size: 16px;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }

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

/* ---------------- Header ---------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  height: var(--nav-h);
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s ease, box-shadow 0.25s ease, background 0.25s ease;
}
.site-header.scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 6px 22px rgba(21, 101, 168, 0.08);
}
.header-inner {
  height: var(--nav-h);
  display: flex;
  align-items: center;
  gap: 28px;
}
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; letter-spacing: 0.2px; }
.logo-mark {
  width: 34px; height: 34px; border-radius: 11px; flex: 0 0 auto;
  background: linear-gradient(140deg, var(--blue-500), var(--blue-700));
  display: grid; place-items: center;
  box-shadow: 0 6px 16px rgba(21, 101, 168, 0.28);
}
.logo-mark svg { width: 19px; height: 19px; }
.logo-text { color: var(--blue-900); }
.logo-text span { color: var(--blue-500); }

.nav { margin-left: auto; display: flex; align-items: center; gap: 6px; }
.nav a {
  padding: 8px 15px; border-radius: 999px;
  font-size: 15px; color: var(--ink-2);
  transition: color 0.2s, background 0.2s;
}
.nav a:hover { color: var(--blue-700); background: var(--blue-50); }
.nav a.active { color: var(--blue-700); background: var(--blue-100); font-weight: 600; }

.header-cta { display: flex; align-items: center; gap: 10px; }

.nav-toggle {
  display: none; margin-left: auto;
  width: 42px; height: 42px; border: 1px solid var(--line); background: var(--white);
  border-radius: 12px; cursor: pointer; padding: 0; place-items: center;
}
.nav-toggle span { display: block; width: 18px; height: 2px; background: var(--blue-700); border-radius: 2px; }
.nav-toggle span + span { margin-top: 4px; }

/* ---------------- Buttons ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 46px; padding: 0 24px; border-radius: 999px;
  font-size: 15px; font-weight: 600; cursor: pointer;
  border: 1px solid transparent; white-space: nowrap;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease, color 0.18s ease;
}
.btn-primary {
  background: linear-gradient(135deg, var(--blue-500), var(--blue-700));
  color: #fff; box-shadow: 0 10px 24px rgba(21, 101, 168, 0.26);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 30px rgba(21, 101, 168, 0.32); }
.btn-ghost { background: var(--white); color: var(--blue-700); border-color: var(--blue-200); }
.btn-ghost:hover { background: var(--blue-50); border-color: var(--blue-300); transform: translateY(-2px); }
.btn-sm { height: 40px; padding: 0 18px; font-size: 14px; }

/* ---------------- Hero ---------------- */
.hero {
  position: relative; overflow: hidden;
  background: linear-gradient(180deg, #e9f4fe 0%, #f4faff 46%, #ffffff 100%);
  padding: 74px 0 66px;
}
.hero::before, .hero::after {
  content: ""; position: absolute; border-radius: 50%; filter: blur(6px); pointer-events: none;
}
.hero::before {
  width: 460px; height: 460px; top: -190px; right: -120px;
  background: radial-gradient(circle at 30% 30%, rgba(111, 188, 244, 0.42), rgba(111, 188, 244, 0) 70%);
}
.hero::after {
  width: 380px; height: 380px; bottom: -180px; left: -140px;
  background: radial-gradient(circle at 60% 40%, rgba(61, 154, 228, 0.26), rgba(61, 154, 228, 0) 70%);
}
.hero-inner { position: relative; display: grid; grid-template-columns: 1.08fr 0.92fr; gap: 54px; align-items: center; }

.pill {
  display: inline-flex; align-items: center; gap: 8px;
  height: 32px; padding: 0 14px; border-radius: 999px;
  background: rgba(255, 255, 255, 0.86); border: 1px solid var(--blue-200);
  color: var(--blue-700); font-size: 13px; font-weight: 600;
  box-shadow: var(--shadow-s);
}
.pill .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--blue-500); box-shadow: 0 0 0 4px rgba(61, 154, 228, 0.18); }

.hero h1 {
  margin: 22px 0 0;
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1.28; letter-spacing: -0.5px;
  color: var(--blue-900); font-weight: 800;
}
.hero h1 em { font-style: normal; color: var(--blue-600); }
.hero .lead {
  margin: 20px 0 0; max-width: 540px;
  font-size: 17px; color: var(--ink-2);
}
.hero-actions { margin-top: 32px; display: flex; gap: 14px; flex-wrap: wrap; }

.hero-figure { position: relative; }
.hero-card {
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid var(--blue-100);
  border-radius: var(--radius-l);
  box-shadow: var(--shadow-l);
  padding: 22px;
}
.hero-card .hc-head { display: flex; align-items: center; gap: 10px; padding-bottom: 14px; border-bottom: 1px dashed var(--blue-200); }
.hero-card .hc-head .avatar {
  width: 34px; height: 34px; border-radius: 11px; display: grid; place-items: center;
  background: var(--blue-100); color: var(--blue-700); font-weight: 700; font-size: 13px;
}
.hero-card .hc-head b { font-size: 14px; color: var(--blue-900); }
.hero-card .hc-head small { display: block; font-size: 12px; color: var(--ink-3); font-weight: 400; }
.hc-row {
  display: flex; gap: 12px; align-items: flex-start;
  padding: 13px 0; border-bottom: 1px solid var(--blue-50);
}
.hc-row:last-child { border-bottom: 0; padding-bottom: 2px; }
.hc-ico {
  width: 30px; height: 30px; flex: 0 0 auto; border-radius: 9px;
  display: grid; place-items: center; background: var(--blue-50); color: var(--blue-600);
}
.hc-ico svg { width: 16px; height: 16px; }
.hc-row p { margin: 0; font-size: 14px; color: var(--ink-2); line-height: 1.6; }
.hc-row p b { color: var(--blue-900); font-weight: 600; }

/* ---------------- Stats ---------------- */
.stats {
  position: relative; z-index: 2;
  margin-top: -6px; padding-bottom: 8px;
}
.stats-band {
  display: grid; grid-template-columns: repeat(3, 1fr);
  background: var(--white);
  border: 1px solid var(--blue-100);
  border-radius: var(--radius-l);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.stat { padding: 30px 26px; text-align: center; position: relative; }
.stat + .stat::before {
  content: ""; position: absolute; left: 0; top: 26px; bottom: 26px; width: 1px;
  background: linear-gradient(180deg, rgba(203, 231, 251, 0), var(--blue-200), rgba(203, 231, 251, 0));
}
.stat .num {
  font-size: clamp(30px, 3.6vw, 40px); font-weight: 800; letter-spacing: -1px;
  background: linear-gradient(135deg, var(--blue-500), var(--blue-700));
  -webkit-background-clip: text; background-clip: text; color: transparent;
  font-variant-numeric: tabular-nums;
}
.stat .num small {
  font-size: 0.6em;
  font-weight: 800;
  margin-left: 3px;
  /* 父级用了 background-clip:text + 透明字色，这里显式上色，确保 "+" 一定可见 */
  color: var(--blue-600);
  -webkit-text-fill-color: var(--blue-600);
}
.stat .lab { margin-top: 4px; font-size: 14px; color: var(--ink-3); }

/* ---------------- Sections ---------------- */
.section { padding: 84px 0; }
.section.tint { background: linear-gradient(180deg, var(--ice), var(--blue-50)); }
.section.dark {
  background: linear-gradient(135deg, var(--blue-800), var(--blue-900));
  color: #fff;
}

.sec-head { max-width: 720px; margin: 0 auto 52px; text-align: center; }
.sec-head.left { margin-left: 0; text-align: left; }
.eyebrow {
  display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 2px;
  color: var(--blue-500); text-transform: uppercase; margin-bottom: 12px;
}
.sec-head h2 {
  margin: 0; font-size: clamp(24px, 3vw, 34px); line-height: 1.35;
  color: var(--blue-900); font-weight: 800; letter-spacing: -0.4px;
}
.section.dark .sec-head h2, .section.dark .sec-head p { color: #fff; }
.sec-head p { margin: 16px 0 0; color: var(--ink-3); font-size: 16px; }
.section.dark .sec-head p { color: rgba(255, 255, 255, 0.76); }

/* ---------------- Cards ---------------- */
.grid { display: grid; gap: 22px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: var(--white);
  border: 1px solid var(--blue-100);
  border-radius: var(--radius);
  padding: 28px 26px;
  box-shadow: var(--shadow-s);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
  height: 100%;
}
.card:hover { transform: translateY(-5px); box-shadow: var(--shadow); border-color: var(--blue-200); }
.card h3 { margin: 16px 0 8px; font-size: 17px; color: var(--blue-900); font-weight: 700; }
.card p { margin: 0; font-size: 14.5px; color: var(--ink-3); line-height: 1.75; }
.card .idx { font-size: 12px; font-weight: 700; color: var(--blue-300); letter-spacing: 1px; }

.ico {
  width: 46px; height: 46px; border-radius: 14px;
  display: grid; place-items: center;
  background: linear-gradient(140deg, var(--blue-100), var(--blue-50));
  color: var(--blue-600);
  border: 1px solid var(--blue-100);
}
.ico svg { width: 23px; height: 23px; }
.ico.solid { background: linear-gradient(140deg, var(--blue-500), var(--blue-700)); color: #fff; border-color: transparent; box-shadow: 0 10px 22px rgba(21,101,168,.24); }

/* ---------------- Compare (痛点/对比) ---------------- */
.compare { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.panel { border-radius: var(--radius); padding: 30px 28px; border: 1px solid var(--line); background: var(--white); }
.panel.before { background: #fbfcfe; border-color: #e6edf4; }
.panel.after {
  background: linear-gradient(160deg, var(--blue-50), #eaf5ff);
  border-color: var(--blue-200);
  box-shadow: var(--shadow);
}
.panel .tag {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 13px; font-weight: 700; padding: 5px 12px; border-radius: 999px;
}
.panel.before .tag { background: #eef2f6; color: #7b8fa3; }
.panel.after .tag { background: var(--white); color: var(--blue-700); border: 1px solid var(--blue-200); }
.panel ul { margin-top: 18px; }
.panel li { position: relative; padding-left: 22px; margin-bottom: 12px; font-size: 15px; color: var(--ink-2); }
.panel li:last-child { margin-bottom: 0; }
.panel.before li::before {
  content: ""; position: absolute; left: 4px; top: 12px; width: 6px; height: 6px;
  border-radius: 50%; background: #c3cfda;
}
.panel.after li::before {
  content: "✓"; position: absolute; left: 0; top: 0;
  color: var(--blue-600); font-weight: 800; font-size: 14px;
}

/* ---------------- Steps ---------------- */
.steps { display: grid; grid-template-columns: repeat(6, 1fr); gap: 14px; }
.step {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: var(--radius);
  padding: 22px 18px; text-align: center;
  transition: transform 0.22s ease, background 0.22s ease;
}
.step:hover { transform: translateY(-5px); background: rgba(255, 255, 255, 0.14); }
.step .n {
  width: 38px; height: 38px; margin: 0 auto 12px; border-radius: 12px;
  display: grid; place-items: center; font-weight: 800; font-size: 14px;
  background: rgba(255, 255, 255, 0.16); color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.24);
}
.step h4 { margin: 0 0 6px; font-size: 16px; font-weight: 700; color: #fff; }
.step p { margin: 0; font-size: 13px; color: rgba(255, 255, 255, 0.72); line-height: 1.6; }

/* ---------------- Feature rows (产品页) ---------------- */
.feature {
  display: grid; grid-template-columns: 1fr 1fr; gap: 46px; align-items: center;
  padding: 34px 0;
}
.feature:nth-child(even) .feature-media { order: -1; }
.feature-body h3 { margin: 14px 0 10px; font-size: 22px; color: var(--blue-900); font-weight: 800; }
.feature-body p { margin: 0 0 16px; color: var(--ink-3); font-size: 15.5px; }
.checks { display: grid; gap: 10px; }
.checks li { position: relative; padding-left: 26px; font-size: 15px; color: var(--ink-2); }
.checks li::before {
  content: "✓"; position: absolute; left: 0; top: 0; width: 18px; height: 18px;
  margin-top: 5px; border-radius: 50%; background: var(--blue-100); color: var(--blue-700);
  font-size: 11px; font-weight: 800; display: grid; place-items: center;
}
.checks li b { color: var(--blue-700); font-weight: 700; }
.feature-media {
  background: linear-gradient(150deg, var(--blue-50), #e8f4fe);
  border: 1px solid var(--blue-100);
  border-radius: var(--radius-l);
  padding: 26px; box-shadow: var(--shadow);
}
.mock { background: var(--white); border-radius: var(--radius); border: 1px solid var(--blue-100); overflow: hidden; box-shadow: var(--shadow-s); }
.mock-bar { display: flex; align-items: center; gap: 6px; padding: 11px 14px; background: var(--blue-50); border-bottom: 1px solid var(--blue-100); }
.mock-bar i { width: 9px; height: 9px; border-radius: 50%; background: var(--blue-200); display: block; }
.mock-bar span { margin-left: 8px; font-size: 12px; color: var(--blue-700); font-weight: 600; }
.mock-body { padding: 16px; display: grid; gap: 10px; }
.mock-chips { display: flex; flex-wrap: wrap; gap: 8px; }
.mock-line { height: 9px; border-radius: 6px; background: var(--blue-100); }
.mock-line.w80 { width: 80%; } .mock-line.w60 { width: 60%; } .mock-line.w92 { width: 92%; }
.mock-chip { display: inline-flex; align-items: center; gap: 6px; height: 26px; padding: 0 11px; border-radius: 8px; background: var(--blue-50); border: 1px solid var(--blue-100); color: var(--blue-700); font-size: 12px; font-weight: 600; }
.tagrow { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }

/* ---------------- CTA band ---------------- */
.cta-band {
  border-radius: 26px; padding: 52px 44px; text-align: center;
  background: linear-gradient(135deg, var(--blue-500), var(--blue-700));
  color: #fff; box-shadow: 0 24px 54px rgba(21, 101, 168, 0.28);
  position: relative; overflow: hidden;
}
.cta-band::after {
  content: ""; position: absolute; width: 340px; height: 340px; border-radius: 50%;
  right: -110px; top: -140px; background: rgba(255, 255, 255, 0.12);
}
.cta-band h2 { margin: 0 0 12px; font-size: clamp(22px, 2.8vw, 30px); font-weight: 800; position: relative; }
.cta-band p { margin: 0 auto 26px; max-width: 540px; color: rgba(255, 255, 255, 0.85); position: relative; }
.cta-band .btn { position: relative; }
.cta-band .btn-white { background: #fff; color: var(--blue-700); box-shadow: 0 10px 26px rgba(11, 58, 99, 0.2); }
.cta-band .btn-white:hover { transform: translateY(-2px); }
.cta-band .btn-outline { background: transparent; color: #fff; border-color: rgba(255, 255, 255, 0.6); }
.cta-band .btn-outline:hover { background: rgba(255, 255, 255, 0.14); }

/* ---------------- Contact ---------------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.field { margin-bottom: 16px; }
.field label { display: block; font-size: 13.5px; font-weight: 600; color: var(--ink-2); margin-bottom: 7px; }
.field input, .field textarea, .field select {
  width: 100%; padding: 12px 14px; font-size: 15px; font-family: inherit; color: var(--ink);
  border: 1px solid var(--line); border-radius: var(--radius-s); background: var(--white);
  transition: border-color 0.2s, box-shadow 0.2s;
}
.field textarea { min-height: 120px; resize: vertical; }
.field input:focus, .field textarea:focus, .field select:focus {
  outline: none; border-color: var(--blue-400); box-shadow: 0 0 0 4px rgba(61, 154, 228, 0.14);
}
.form-note { font-size: 13px; color: var(--ink-3); margin-top: 12px; }
.contact-action {
  display: flex; align-items: center; gap: 14px;
  padding: 14px 16px; margin-top: 12px;
  border-radius: var(--radius-s);
  background: var(--blue-50); border: 1px solid var(--blue-100);
  transition: background .2s, border-color .2s, transform .2s;
}
.contact-action:hover { background: #e8f4fe; border-color: var(--blue-200); transform: translateY(-1px); }
.contact-action .ico { width: 42px; height: 42px; border-radius: 12px; flex: none; }
.contact-action .ca-body { min-width: 0; }
.contact-action b { display: block; font-size: 16px; color: var(--blue-900); }
.contact-action em { display: block; font-style: normal; font-size: 13px; color: var(--ink-3); margin-top: 3px; }
.contact-list { display: grid; gap: 18px; }
.contact-item { display: flex; gap: 14px; align-items: flex-start; }
.contact-item .ico { width: 42px; height: 42px; border-radius: 12px; }
.contact-item b { display: block; font-size: 15px; color: var(--blue-900); }
.contact-item span { font-size: 14px; color: var(--ink-3); }

/* ---------------- Footer ---------------- */
.site-footer { background: #f2f8fe; border-top: 1px solid var(--line); padding: 52px 0 26px; }
.footer-top { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 34px; }
.footer-brand p { margin: 14px 0 0; font-size: 14px; color: var(--ink-3); max-width: 300px; }
.footer-col h4 { margin: 0 0 14px; font-size: 14px; color: var(--blue-900); font-weight: 700; }
.footer-col a { display: block; font-size: 14px; color: var(--ink-3); padding: 5px 0; transition: color 0.18s; }
.footer-col a:hover { color: var(--blue-600); }
.footer-bottom {
  margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--line);
  display: flex; justify-content: space-between; gap: 14px; flex-wrap: wrap;
  font-size: 13px; color: var(--ink-3);
}
.footer-bottom a { color: inherit; transition: color 0.18s; }
.footer-bottom a:hover { color: var(--blue-600); }

/* ---------------- Page hero (内页) ---------------- */
.page-hero {
  background: linear-gradient(180deg, #e9f4fe, #f6fbff);
  padding: 62px 0 56px; position: relative; overflow: hidden;
  border-bottom: 1px solid var(--blue-100);
}
.page-hero::after {
  content: ""; position: absolute; width: 420px; height: 420px; border-radius: 50%;
  right: -140px; top: -200px;
  background: radial-gradient(circle, rgba(111, 188, 244, 0.35), rgba(111, 188, 244, 0) 70%);
}
.page-hero .container { position: relative; }
.page-hero h1 { margin: 14px 0 0; font-size: clamp(26px, 3.4vw, 38px); color: var(--blue-900); font-weight: 800; letter-spacing: -0.4px; }
.page-hero p { margin: 14px 0 0; max-width: 640px; color: var(--ink-2); font-size: 16px; }
.crumb { font-size: 13px; color: var(--ink-3); }
.crumb a:hover { color: var(--blue-600); }

/* ---------------- Reveal animation ---------------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.6s ease, transform 0.6s cubic-bezier(0.22, 1, 0.36, 1); }
.reveal.in { opacity: 1; transform: none; }

/* ---------------- Responsive ---------------- */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero .lead { max-width: none; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(3, 1fr); }
  .footer-top { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 860px) {
  .nav-toggle { display: grid; }
  .header-cta { display: none; }
  .nav {
    position: absolute; left: 0; right: 0; top: var(--nav-h);
    flex-direction: column; align-items: stretch; gap: 2px;
    background: #fff; padding: 12px 24px 20px;
    border-bottom: 1px solid var(--line); box-shadow: 0 18px 30px rgba(21, 101, 168, 0.1);
    display: none;
  }
  .nav.open { display: flex; }
  .nav a { padding: 12px 6px; border-radius: 10px; }
  .header-inner { position: relative; }
  .grid-3, .grid-2, .compare, .contact-grid, .feature { grid-template-columns: 1fr; }
  .feature:nth-child(even) .feature-media { order: 0; }
  .stats-band { grid-template-columns: 1fr; }
  .stat + .stat::before { display: none; }
  .stat + .stat { border-top: 1px solid var(--blue-100); }
  .section { padding: 62px 0; }
  .cta-band { padding: 40px 24px; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .footer-top { grid-template-columns: 1fr; gap: 26px; }
}