/* XClass — shared public design system
   Used by index.html and dedicated public pages.
   Logo: /images/logo-xclass.png (original, do not modify). */

:root{
  --bg:#FFFFFF;
  --bg-2:#F7F9FC;
  --text:#172033;
  --text-2:#5C667A;
  --primary:#3157D5;
  --primary-hover:#2648BC;
  --accent:#66C3A5;
  --border:#E6EAF0;
  --radius:18px;
  --shadow:0 1px 2px rgba(23,32,51,.04),0 18px 44px rgba(23,32,51,.08);
  --font:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:var(--font);color:var(--text);background:var(--bg);line-height:1.65;-webkit-font-smoothing:antialiased;font-size:18px;overflow-x:hidden}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{max-width:1160px;margin:0 auto;padding:0 28px}

/* Buttons */
.btn{display:inline-flex;align-items:center;gap:8px;font-family:var(--font);font-weight:600;font-size:16px;padding:15px 26px;border-radius:12px;border:1px solid transparent;cursor:pointer;transition:.18s ease}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-hover);transform:translateY(-1px)}
.btn-secondary{background:#fff;color:var(--primary);border-color:var(--border)}
.btn-secondary:hover{border-color:var(--primary);background:var(--bg-2)}
.btn-ghost{background:transparent;color:var(--text);border-color:var(--border)}
.btn-ghost:hover{border-color:var(--primary);color:var(--primary)}

/* Typography helpers */
.eyebrow{display:inline-block;font-size:13px;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:var(--primary);margin-bottom:22px}
.section{padding:128px 0}
.page-section{padding:104px 0}
.section-head{max-width:720px;margin:0 auto 56px;text-align:center}
.section-head h2{font-size:clamp(30px,4.6vw,48px);font-weight:800;letter-spacing:-.025em;line-height:1.12}
.section-head p{margin-top:18px;color:var(--text-2);font-size:19px;line-height:1.6}
.muted{color:var(--text-2)}
.kicker{font-size:14px;font-weight:600;color:var(--text-2)}

/* Header */
header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.88);backdrop-filter:blur(12px);border-bottom:1px solid var(--border)}
.nav{display:flex;align-items:center;justify-content:space-between;height:74px}
.logo{display:flex;align-items:center}
.logo-img{height:32px;width:auto;display:block}
.nav-links{display:flex;gap:34px;font-size:16px;font-weight:500;color:var(--text-2)}
.nav-links a:hover{color:var(--primary)}
.nav-cta{display:flex;align-items:center;gap:20px}
.nav-cta .signin{font-size:16px;font-weight:600;color:var(--text-2)}
.nav-cta .signin:hover{color:var(--primary)}
@media(max-width:980px){.nav-links{display:none}}

/* Footer */
footer{border-top:1px solid var(--border);padding:64px 0 36px;color:var(--text-2);font-size:15px}
.foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:36px;margin-bottom:44px}
@media(max-width:820px){.foot-grid{grid-template-columns:1fr 1fr;gap:32px}}
@media(max-width:480px){.foot-grid{grid-template-columns:1fr}}
.foot-brand .logo-img{height:36px;margin-bottom:16px}
.foot-brand p{max-width:300px;font-size:15px}
.foot-grid h4{font-size:13px;text-transform:uppercase;letter-spacing:.05em;color:var(--text);margin-bottom:16px;font-weight:700}
.foot-grid a{display:block;padding:6px 0;color:var(--text-2);font-size:15px}
.foot-grid a:hover{color:var(--primary)}
.foot-bottom{border-top:1px solid var(--border);padding-top:24px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;font-size:13.5px}

/* Reveal */
.reveal{opacity:0;transform:translateY(20px);transition:opacity .7s ease,transform .7s ease}
.reveal.in{opacity:1;transform:none}
@media(prefers-reduced-motion:reduce){
  .reveal{opacity:1;transform:none;transition:none}
  .btn{transition:none}
}

/* ============ Dedicated-page helpers ============ */

/* Page hero (interior pages) */
.page-hero{padding:96px 0 64px;background:linear-gradient(180deg,#fff 0%,var(--bg-2) 100%)}
.page-hero .eyebrow{margin-bottom:18px}
.page-hero h1{font-size:clamp(34px,5vw,56px);line-height:1.08;font-weight:800;letter-spacing:-.03em;margin-bottom:22px;max-width:14ch}
.page-hero p.lead{font-size:20px;color:var(--text-2);max-width:560px;line-height:1.6}
.page-hero .hero-actions{display:flex;gap:16px;flex-wrap:wrap;margin-top:34px}
@media(max-width:720px){.page-hero{padding:64px 0 48px}.page-hero p.lead{font-size:18px}}

/* Split content row */
.split{display:grid;grid-template-columns:1fr 1.05fr;gap:64px;align-items:center}
@media(max-width:920px){.split{grid-template-columns:1fr;gap:40px}}

/* Minimal feature row (understated, thin top rule) */
.feature-row{display:grid;grid-template-columns:repeat(3,1fr);gap:48px}
.feature{padding-top:26px;border-top:2px solid var(--text)}
.feature .num{font-size:15px;font-weight:700;color:var(--primary);letter-spacing:.05em;margin-bottom:18px}
.feature h3{font-size:23px;font-weight:800;letter-spacing:-.02em;margin-bottom:12px}
.feature p{color:var(--text-2);font-size:17px}
@media(max-width:880px){.feature-row{grid-template-columns:1fr;gap:0}.feature{margin-bottom:40px;padding-top:22px}.feature:last-child{margin-bottom:0}}

/* Large media frame */
.media-frame{border-radius:24px;overflow:hidden;box-shadow:var(--shadow);border:1px solid var(--border);background:var(--bg-2)}
.media-frame img{width:100%;display:block;aspect-ratio:4/3;object-fit:cover}

/* Simple link list (small navigation links) */
.link-list{display:flex;flex-direction:column;margin-top:8px}
.link-list a{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:20px 4px;border-bottom:1px solid var(--border);font-size:20px;font-weight:700;letter-spacing:-.01em;transition:.18s}
.link-list a:first-child{border-top:1px solid var(--border)}
.link-list a svg{color:var(--text-2);flex:0 0 auto;transition:.18s}
.link-list a:hover{color:var(--primary)}
.link-list a:hover svg{color:var(--primary);transform:translateX(4px)}
@media(max-width:620px){.link-list a{font-size:18px}}

/* Minimal card (no price) */
.card{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:40px;box-shadow:var(--shadow)}
.card .tag{font-size:13px;font-weight:700;color:var(--primary);text-transform:uppercase;letter-spacing:.06em}
.card h3{font-size:26px;font-weight:800;letter-spacing:-.02em;margin:14px 0 10px}
.card .sub{color:var(--text-2);font-size:17px;margin-bottom:22px}
.card p{color:var(--text-2);font-size:16.5px;line-height:1.6}
.card .card-cta{margin-top:26px}

/* Accordion (FAQ) */
.accordion{max-width:840px;margin:0 auto}
.acc-item{border:1px solid var(--border);border-radius:14px;margin-bottom:14px;overflow:hidden}
.acc-q{width:100%;text-align:left;background:#fff;border:none;padding:22px 24px;font-size:18px;font-weight:600;cursor:pointer;display:flex;justify-content:space-between;align-items:center;gap:16px;font-family:var(--font);color:var(--text)}
.acc-q svg{transition:.2s;flex:0 0 auto;color:var(--text-2)}
.acc-item.open .acc-q svg{transform:rotate(180deg)}
.acc-a{max-height:0;overflow:hidden;transition:.28s ease;background:var(--bg-2)}
.acc-a p{padding:0 24px;color:var(--text-2);font-size:16.5px;line-height:1.6}
.acc-item.open .acc-a{max-height:320px;padding:16px 0}

/* Simple prose */
.prose{max-width:720px}
.prose h2{font-size:clamp(26px,3.4vw,38px);font-weight:800;letter-spacing:-.02em;margin:0 0 18px;line-height:1.15}
.prose p{color:var(--text-2);font-size:18px;margin-bottom:18px}

/* Chat window mockup */
.tutor-window{background:#fff;border:1px solid var(--border);border-radius:22px;box-shadow:var(--shadow);overflow:hidden}
.tw-bar{display:flex;align-items:center;gap:7px;padding:15px 18px;border-bottom:1px solid var(--border);background:var(--bg-2)}
.tw-bar .dot{width:10px;height:10px;border-radius:50%;background:#D7DEEA}
.tw-bar .title{margin-left:10px;font-size:13.5px;font-weight:600;color:var(--text-2)}
.tw-body{padding:24px}
.msg{display:flex;gap:12px;margin-bottom:18px}
.msg.me{justify-content:flex-end}
.msg .av{width:34px;height:34px;border-radius:10px;flex:0 0 auto;display:flex;align-items:center;justify-content:center;font-weight:700;font-size:13px;color:#fff}
.msg.ai .av{background:var(--primary)}
.msg.me .av{background:var(--accent);color:#0d2b22}
.msg .bub{background:var(--bg-2);border:1px solid var(--border);border-radius:14px;padding:13px 16px;font-size:15px;color:var(--text);line-height:1.55;max-width:80%}
.msg.me .bub{background:var(--primary);color:#fff;border-color:var(--primary)}
.msg .bub code{background:rgba(23,32,51,.07);padding:1px 6px;border-radius:6px;font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:13.5px}
.msg.me .bub code{background:rgba(255,255,255,.22)}

/* Trial box (shared visual) */
.trial{background:linear-gradient(135deg,#1f3aa8,#3157D5);border-radius:28px;padding:64px;display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:center;color:#fff}
@media(max-width:920px){.trial{grid-template-columns:1fr;padding:40px;gap:34px}}
.trial h2{font-size:clamp(28px,3.4vw,38px);font-weight:800;letter-spacing:-.02em;margin-bottom:16px}
.trial p{color:rgba(255,255,255,.86);font-size:18px;max-width:440px}
.trial form{background:#fff;border-radius:18px;padding:30px;color:var(--text)}
.trial label{display:block;font-size:13.5px;font-weight:600;color:var(--text-2);margin:0 0 7px}
.trial input,.trial select{width:100%;padding:13px 15px;border:1px solid var(--border);border-radius:11px;font-family:var(--font);font-size:16px;margin-bottom:16px;color:var(--text);background:#fff}
.trial input:focus,.trial select:focus{outline:none;border-color:var(--primary)}
.trial .btn-primary{width:100%;justify-content:center}
.trial .note{font-size:13px;color:var(--text-2);margin-top:12px;text-align:center}
.success{display:none;background:#fff;border-radius:18px;padding:38px 30px;text-align:center;color:var(--text)}
.success svg{color:var(--accent);margin-bottom:14px}
.success h3{font-size:24px;font-weight:800;margin-bottom:10px}
.success p{color:var(--text-2);font-size:16px}

/* Closing CTA */
.final{text-align:center;background:var(--bg-2);border-radius:28px;padding:88px 24px}
.final h2{font-size:clamp(28px,4vw,44px);font-weight:800;letter-spacing:-.025em;margin-bottom:18px;line-height:1.12}
.final p{color:var(--text-2);max-width:580px;margin:0 auto 30px;font-size:19px}
@media(max-width:620px){.final{padding:60px 22px}}