/* =========================================================
   SampleLearn: shared styles (tokens, nav, buttons, motion)
   Motion language follows the AGS-MASAR UI: short opacity
   fades, gentle press feedback, frosted sheets, safe areas.
   ========================================================= */
:root{
  --blue:#0071e3; --blue-dark:#0058b0; --blue-soft:#e8f2fd;
  --ink:#1d1d1f; --ink-2:#6e6e73; --line:#e5e5ea;
  --bg:#ffffff; --bg-2:#f5f5f7; --logo-bg:#f2f1ec;
  --radius:22px;
  --font:-apple-system, BlinkMacSystemFont, "SF Pro Display", "Inter", "Segoe UI Variable", "Segoe UI", Helvetica, Arial, sans-serif;
  --mono:ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --ease:cubic-bezier(.25,.1,.25,1);
  --fade:.25s;          /* MASAR view fade */
  --fade-slow:.6s;      /* scroll reveals */
  --safe-t:env(safe-area-inset-top,0px);
  --safe-b:env(safe-area-inset-bottom,0px);
  --safe-l:env(safe-area-inset-left,0px);
  --safe-r:env(safe-area-inset-right,0px);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;scroll-padding-top:calc(64px + var(--safe-t))}
body{font-family:var(--font);color:var(--ink);background:var(--bg);-webkit-font-smoothing:antialiased;line-height:1.5;-webkit-tap-highlight-color:transparent}
a{color:inherit;text-decoration:none}
img,svg{display:block;max-width:100%}
.wrap{max-width:1120px;margin:0 auto;padding:0 max(22px,var(--safe-l)) 0 max(22px,var(--safe-r))}
.label{font-size:12px;font-weight:600;letter-spacing:.05em;text-transform:uppercase;color:var(--blue)}

/* ---------- Page fade in / fade out ---------- */
body{opacity:0;transition:opacity var(--fade) ease}
body.ready{opacity:1}
body.leaving{opacity:0;transition-duration:.2s}

/* ---------- Navigation (frosted, safe-area aware) ---------- */
.nav{position:sticky;top:0;z-index:50;padding-top:var(--safe-t);background:rgba(255,255,255,.72);backdrop-filter:saturate(180%) blur(20px);-webkit-backdrop-filter:saturate(180%) blur(20px);border-bottom:1px solid rgba(0,0,0,.06)}
.nav .wrap{display:flex;align-items:center;justify-content:space-between;height:56px;gap:16px}
.brand{display:flex;align-items:center;gap:9px;font-weight:600;font-size:19px;letter-spacing:-.02em}
.brand span b{color:var(--blue);font-weight:600}
.nav ul{display:flex;gap:28px;list-style:none;font-size:14px;color:var(--ink-2)}
.nav ul a{transition:color .2s}
.nav ul a:hover{color:var(--ink)}
.burger{display:none;width:44px;height:44px;margin-right:-10px;background:none;border:0;cursor:pointer;position:relative}
.burger i{position:absolute;left:12px;width:20px;height:1.5px;background:var(--ink);border-radius:2px;transition:transform .3s var(--ease), top .3s var(--ease)}
.burger i:first-child{top:17px}.burger i:last-child{top:25px}
.menu-open .burger i:first-child{top:21px;transform:rotate(45deg)}
.menu-open .burger i:last-child{top:21px;transform:rotate(-45deg)}

/* ---------- Buttons ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;border-radius:980px;font:500 15px var(--font);padding:11px 22px;border:0;cursor:pointer;transition:transform .15s, background .2s, box-shadow .2s;min-height:44px}
.btn:active{transform:scale(.985)}
.btn-primary{background:var(--blue);color:#fff;box-shadow:0 10px 24px -14px rgba(0,113,227,.8)}
.btn-primary:hover{background:var(--blue-dark)}
.btn-ghost{color:var(--blue);padding-left:8px;padding-right:8px}
.btn-sm{padding:7px 16px;font-size:13px;min-height:34px}

/* ---------- Reveal: opacity-only fade, staggered ---------- */
.reveal{opacity:0;transition:opacity var(--fade-slow) ease;transition-delay:var(--d,0ms)}
.reveal.in{opacity:1}

/* Images fade in once loaded */
img.fade{opacity:0;transition:opacity .5s ease}
img.fade.loaded{opacity:1}

/* ---------- Toast ---------- */
.toast{position:fixed;left:50%;bottom:calc(24px + var(--safe-b));transform:translateX(-50%);background:rgba(29,29,31,.92);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);color:#fff;font-size:14px;padding:12px 20px;border-radius:980px;opacity:0;visibility:hidden;transition:opacity var(--fade) ease, visibility 0s linear var(--fade);z-index:99;white-space:nowrap}
.toast.show{opacity:1;visibility:visible;transition-delay:0s}

/* ---------- Footer ---------- */
footer{background:var(--bg-2);padding:56px 0 calc(30px + var(--safe-b));font-size:13px;color:var(--ink-2);border-top:1px solid var(--line)}
footer .cols{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:30px;padding-bottom:30px;border-bottom:1px solid var(--line)}
footer h4{color:var(--ink);font-size:13px;font-weight:600;margin-bottom:12px}
footer li{list-style:none;margin-bottom:8px}
footer a{transition:color .2s}
footer a:hover{color:var(--ink)}
footer .legal{display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px;padding-top:20px}

/* ---------- Phone: frosted sheet menu that fades ---------- */
@media (max-width:720px){
  .nav .btn-sm{display:none}
  .burger{display:block}
  /* the frosted nav is the containing block, so size the sheet to the viewport explicitly */
  .nav ul{position:absolute;left:0;right:0;top:100%;height:calc(100vh - 57px - var(--safe-t));height:calc(100dvh - 57px - var(--safe-t));flex-direction:column;gap:0;padding:12px max(22px,var(--safe-l)) calc(24px + var(--safe-b));background:rgba(255,255,255,.985);border-top:1px solid rgba(0,0,0,.06);opacity:0;visibility:hidden;transition:opacity var(--fade) ease, visibility 0s linear var(--fade)}
  .menu-open .nav ul{opacity:1;visibility:visible;transition-delay:0s}
  .nav ul li{border-bottom:1px solid var(--line)}
  .nav ul li a{display:flex;align-items:center;min-height:56px;font-size:22px;font-weight:600;letter-spacing:-.02em;color:var(--ink)}
  .menu-open{overflow:hidden}
  footer .cols{grid-template-columns:1fr 1fr}
}

/* Respect reduced-motion settings everywhere (as MASAR does) */
@media (prefers-reduced-motion:reduce){
  *{animation:none!important;transition:none!important}
  body,.reveal,img.fade{opacity:1!important}
  html{scroll-behavior:auto}
}