:root {
  --bg: #f7f8f3;
  --surface: #ffffff;
  --surface-2: #f0f3ea;
  --text: #17352a;
  --muted: #65736b;
  --line: #dfe6dc;
  --green: #174d35;
  --green-2: #226b49;
  --lemon: #dff34d;
  --lemon-2: #cde633;
  --danger: #8a4b2c;
  --shadow: 0 14px 45px rgba(23, 53, 42, .08);
  --radius: 20px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
}
button, input { font: inherit; }
button { cursor: pointer; }
a { color: inherit; text-decoration: none; }
::selection { background: var(--lemon); color: var(--green); }

.container { width: min(1160px, calc(100% - 36px)); margin: 0 auto; }

.demo-bar {
  background: var(--green);
  color: #fff;
  text-align: center;
  padding: 8px 16px;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .08em;
}

.nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(247,248,243,.9);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(223,230,220,.8);
}
.nav-inner {
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.logo { display:flex; align-items:center; gap:10px; font-weight:900; font-size:21px; letter-spacing:-.04em; }
.logo-mark {
  width: 34px; height: 34px; border-radius: 11px;
  background: var(--lemon); display:grid; place-items:center;
  color: var(--green); box-shadow: inset 0 -2px 0 rgba(0,0,0,.08);
}
.nav-links { display:flex; align-items:center; gap: 4px; }
.nav-links a {
  padding: 9px 12px; border-radius: 10px; color: var(--muted); font-weight: 700; font-size: 14px;
}
.nav-links a:hover, .nav-links a.active { color: var(--green); background: var(--surface-2); }
.nav-actions { display:flex; align-items:center; gap: 8px; }

.btn {
  border: 0; border-radius: 12px; padding: 11px 16px; font-weight: 800;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--green); color: white; box-shadow: 0 8px 20px rgba(23,77,53,.18); }
.btn-primary:hover { background: var(--green-2); }
.btn-lemon { background: var(--lemon); color: var(--green); }
.btn-ghost { background: transparent; color: var(--green); border: 1px solid var(--line); }

.hero { padding: 84px 0 55px; overflow:hidden; }
.hero-grid { display:grid; grid-template-columns: 1.12fr .88fr; gap: 55px; align-items:center; }
.eyebrow {
  display:inline-flex; align-items:center; gap:8px; padding:6px 10px; border-radius:999px;
  background: #eef5c8; color: var(--green); font-size:12px; font-weight:900; text-transform:uppercase; letter-spacing:.07em;
}
.eyebrow-dot { width:7px; height:7px; border-radius:50%; background:var(--green-2); }
h1 { font-size: clamp(44px, 6vw, 76px); line-height:.98; letter-spacing:-.065em; margin:18px 0 22px; max-width:800px; }
.hero p { color:var(--muted); font-size:18px; max-width:650px; }
.actions { display:flex; gap:10px; flex-wrap:wrap; margin-top:28px; }

.hero-card {
  min-height: 390px; background: var(--green); color:#fff; border-radius:32px; padding:24px;
  box-shadow: var(--shadow); position:relative; overflow:hidden;
}
.hero-card:before, .hero-card:after {
  content:""; position:absolute; border-radius:50%; background:rgba(223,243,77,.12);
}
.hero-card:before { width:240px; height:240px; right:-75px; top:-75px; }
.hero-card:after { width:180px; height:180px; left:-80px; bottom:-90px; }
.mock-window { position:relative; z-index:1; background:#f8faf5; color:var(--text); border-radius:20px; padding:17px; margin-top:45px; }
.mock-top { display:flex; justify-content:space-between; align-items:center; margin-bottom:18px; }
.pills { display:flex; gap:5px; }
.pill { width:8px; height:8px; border-radius:50%; background:#ccd4ca; }
.mini-grid { display:grid; grid-template-columns: 1fr 1fr; gap:10px; }
.mini-card { background:white; border:1px solid var(--line); border-radius:14px; padding:14px; }
.mini-card strong { display:block; font-size:14px; }
.progress { height:8px; border-radius:99px; background:#e8ede4; overflow:hidden; }
.progress > span { display:block; height:100%; background:var(--green-2); border-radius:inherit; }

.announcement {
  margin: 10px 0 20px; border:1px solid #e7dccd; background:#fffaf2; color:#634b35;
  border-radius:16px; padding:14px 16px; display:flex; gap:12px; align-items:flex-start;
}
.announcement b { color:#4b3827; }

.section { padding: 55px 0; }
.section-head { display:flex; align-items:end; justify-content:space-between; gap:20px; margin-bottom:22px; }
.section-head h2 { margin:0; font-size:32px; letter-spacing:-.04em; }
.section-head p { margin:0; color:var(--muted); max-width:560px; }

.feature-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:14px; }
.feature, .card { background:var(--surface); border:1px solid var(--line); border-radius:var(--radius); box-shadow:var(--shadow); }
.feature { padding:22px; }
.feature-icon { width:42px;height:42px;border-radius:13px;background:#eef5c8;display:grid;place-items:center;font-size:20px;margin-bottom:18px; }
.feature h3 { margin:0 0 6px; font-size:18px; }
.feature p { color:var(--muted); margin:0; font-size:14px; }

.social-proof { background:var(--green); color:#fff; border-radius:28px; padding:34px; margin:35px 0 65px; display:flex; align-items:center; justify-content:space-between; gap:25px; }
.social-proof p { color:#c9d9d0; margin:6px 0 0; }
.demo-tag { color:var(--lemon); font-weight:900; font-size:12px; letter-spacing:.08em; }

.page { padding:50px 0 80px; }
.page-title { margin-bottom:30px; }
.page-title h1 { font-size:52px; margin:0 0 10px; }
.page-title p { margin:0; color:var(--muted); max-width:680px; }

.course-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:18px; }
.course-card { overflow:hidden; }
.course-cover { min-height:145px; padding:20px; background:linear-gradient(135deg,#edf5bf,#d9e7cf); display:flex; justify-content:space-between; align-items:flex-start; }
.course-cover .subject { font-weight:900; font-size:13px; color:var(--green); }
.course-emoji { font-size:40px; }
.course-body { padding:20px; }
.course-body h3 { margin:0 0 7px; font-size:21px; }
.course-body p { color:var(--muted); font-size:14px; margin:0 0 15px; }
.meta { display:flex; justify-content:space-between; gap:8px; color:var(--muted); font-size:12px; font-weight:700; margin-bottom:12px; }
.instructor { font-size:13px; margin:14px 0; }
.course-body .btn { width:100%; }

.detail-layout { display:grid; grid-template-columns:1fr 350px; gap:22px; align-items:start; }
.detail-main, .side-card { padding:28px; }
.detail-main h2 { margin-top:0; }
.lesson { display:flex; align-items:center; gap:14px; padding:15px 0; border-top:1px solid var(--line); }
.lesson-number { width:34px;height:34px;border-radius:10px;background:var(--surface-2);display:grid;place-items:center;font-weight:900; }
.lesson-main { flex:1; }
.lesson-main strong { display:block; }
.lesson-main span { color:var(--muted); font-size:12px; }
.side-card { position:sticky; top:95px; }
.big-progress { height:11px; margin:13px 0 18px; }
.demo-toast {
  position:fixed; right:20px; bottom:20px; z-index:100; max-width:350px;
  background:var(--green); color:white; padding:14px 17px; border-radius:14px;
  box-shadow:0 15px 40px rgba(0,0,0,.2); animation:toastIn .25s ease;
}
@keyframes toastIn { from { transform:translateY(12px); opacity:0; } to { transform:none; opacity:1; } }

.dashboard-grid { display:grid; grid-template-columns: 1.15fr .85fr; gap:18px; }
.profile-card { padding:25px; display:flex; align-items:center; gap:16px; }
.avatar { width:58px;height:58px;border-radius:18px;background:var(--lemon);display:grid;place-items:center;font-size:21px;font-weight:900;color:var(--green); }
.stat-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:12px; margin-top:15px; }
.stat { padding:18px; background:var(--surface-2); border-radius:16px; }
.stat strong { display:block; font-size:25px; }
.stat span { color:var(--muted); font-size:12px; }
.assignment { padding:17px 0; border-bottom:1px solid var(--line); }
.assignment:last-child { border-bottom:0; }
.assignment-top { display:flex; justify-content:space-between; gap:10px; }
.assignment small { color:var(--muted); }

.login-wrap { min-height:calc(100vh - 190px); display:grid; place-items:center; padding:55px 0; }
.login-card { width:min(450px,100%); padding:32px; }
.login-card h1 { font-size:40px; margin:12px 0 8px; }
.login-card > p { color:var(--muted); }
.demo-notice { background:#eef5c8; color:var(--green); border-radius:13px; padding:12px; font-size:13px; font-weight:800; margin:20px 0; }
.field { margin:15px 0; }
.field label { display:block; font-size:13px; font-weight:800; margin-bottom:7px; }
.field input { width:100%; border:1px solid var(--line); border-radius:12px; padding:12px 13px; outline:none; background:#fff; color:var(--text); }
.field input:focus { border-color:var(--green-2); box-shadow:0 0 0 3px rgba(34,107,73,.1); }
.login-card .btn { width:100%; margin-top:7px; }

.about-grid { display:grid; grid-template-columns:1fr 1fr; gap:18px; }
.about-card { padding:28px; }
.about-card p { color:var(--muted); }
.quote { background:var(--green); color:white; padding:25px; border-radius:20px; margin-top:20px; }
.quote p { color:#d4e1db; }

.footer { border-top:1px solid var(--line); padding:28px 0; color:var(--muted); font-size:13px; }
.footer-inner { display:flex; justify-content:space-between; gap:20px; flex-wrap:wrap; }
.footer strong { color:var(--green); }
.footer-demo { font-weight:900; color:#9a4e2e; letter-spacing:.05em; }

.mobile-menu { display:none; }

@media (max-width: 900px) {
  .hero-grid, .detail-layout, .dashboard-grid, .about-grid { grid-template-columns:1fr; }
  .course-grid { grid-template-columns:repeat(2,1fr); }
  .feature-grid { grid-template-columns:repeat(2,1fr); }
  .side-card { position:static; }
  .nav-links { display:none; }
  .mobile-menu { display:block; }
}
@media (max-width: 620px) {
  .container { width:min(100% - 24px, 1160px); }
  .nav-actions .btn-ghost { display:none; }
  .hero { padding-top:50px; }
  h1, .page-title h1 { font-size:42px; }
  .course-grid, .feature-grid, .stat-grid { grid-template-columns:1fr; }
  .social-proof { display:block; }
  .hero-card { min-height:330px; }
  .mini-grid { grid-template-columns:1fr; }
}

/* whiter gradient + polish */
body { background: linear-gradient(180deg, #fff 0%, #fdfefb 40%, #f5f8ef 100%) fixed; min-height: 100vh; }
.nav { background: rgba(255,255,255,.88); }
.hero { background: radial-gradient(900px 420px at 75% -10%, #fff 0%, rgba(255,255,255,0) 70%); }
.demo-bar { font-weight: 600; letter-spacing: .02em; font-size: 13px; }
.hero-photo { border-radius: 32px; overflow: hidden; box-shadow: var(--shadow); border: 1px solid var(--line); background: #fff; }
.scene { display: block; width: 100%; height: 100%; }
.hero-photo .scene { aspect-ratio: 400 / 260; }
.trust { background: #fff; border-block: 1px solid var(--line); }
.trust-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 26px 0; flex-wrap: wrap; }
.trust-inner > div:first-child strong { display: block; font-size: 22px; letter-spacing: -.03em; }
.trust-inner span { color: var(--muted); font-size: 14px; }
.trust-stats { display: flex; gap: 40px; }
.trust-stats b { display: block; font-size: 26px; letter-spacing: -.04em; color: var(--green); }
.learners { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-top: 32px; }
.learners figure { margin: 0; border-radius: 22px; overflow: hidden; border: 1px solid var(--line); aspect-ratio: 4 / 3; }
.review-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.review { margin: 0; padding: 26px; display: flex; flex-direction: column; gap: 16px; }
.review blockquote { margin: 0; flex: 1; font-size: 16px; line-height: 1.6; }
.stars { color: #d4a514; letter-spacing: 2px; }
.review figcaption { display: flex; gap: 12px; align-items: center; }
.review figcaption strong, .review figcaption small { display: block; }
.review small { color: var(--muted); font-size: 12px; }
.avatar.sm { width: 40px; height: 40px; border-radius: 12px; font-size: 14px; flex: none; }
.about-card.hero-photo { padding: 0; }
.btn:focus-visible, a:focus-visible { outline: 3px solid var(--green-2); outline-offset: 2px; }
@media (max-width: 900px) { .review-grid { grid-template-columns: 1fr; } .learners { grid-template-columns: 1fr; } }
@media (prefers-reduced-motion: reduce) { .btn { transition: none; } }

.face-card { border-radius: 32px; background: linear-gradient(160deg, #f3fbc4, var(--lemon) 70%); box-shadow: var(--shadow); border: 1px solid #d5e35a; padding: 26px; aspect-ratio: 400 / 300; display: grid; place-items: center; }
.face-card svg { width: 100%; height: 100%; overflow: visible; }
.face-card .pupil, .face-card .glint { transition: transform .12s ease-out; }
.face-card .mouth { transition: d .15s ease-out; }
.face-card .lid { transform-box: fill-box; transform-origin: center; animation: blink 5s infinite; }
@keyframes blink { 0%, 94%, 100% { transform: scaleY(1); } 97% { transform: scaleY(.08); } }
@media (prefers-reduced-motion: reduce) { .face-card .lid { animation: none; } }
.login-card input:disabled, .login-card .btn:disabled { opacity: .55; cursor: not-allowed; transform: none; }

.logo-mark { width: 44px; height: 34px; background: none; box-shadow: none; border-radius: 0; display: block; }
.face-card { background: none; border: 0; box-shadow: none; padding: 0; }
.face-card .lemon-body { filter: drop-shadow(0 22px 22px rgba(120, 100, 10, .22)); }