/* YHD v2 design system: global header, mega menu, footer, app shell, components. Brand book tokens. */
:root{--r:#1957D8;--ru:#1F3FBF;--rd:#132A8A;--nv:#0F1B3D;--nv2:#0A1330;--tn:#EEF1FB;--tn2:#F5F7FC;--ink:#0F1630;--mu:#5B6585;--ln:#E6E9F3;--bdr:#D5DBEF;--gold:#C9A227;--ok:#0F7A45;--okb:#E8F6EE;
--sh1:0 1px 2px rgba(15,22,48,.06),0 1px 1px rgba(15,22,48,.04);--sh2:0 2px 4px rgba(15,22,48,.04),0 8px 24px rgba(19,42,138,.08);--sh3:0 4px 8px rgba(15,22,48,.05),0 24px 60px rgba(19,42,138,.16);--rad:16px;--ease:cubic-bezier(.2,.7,.2,1)}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}body{font-family:"Heebo",system-ui,-apple-system,"Segoe UI",Arial,sans-serif;-webkit-font-smoothing:antialiased;color:var(--ink)}
.ic{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;flex:none}
.mono{font-family:"IBM Plex Mono",ui-monospace,Menlo,monospace}
.skip{position:absolute;inset-inline-start:-999px;top:8px;background:#fff;padding:8px 14px;border-radius:8px;z-index:200;box-shadow:var(--sh2)}.skip:focus{inset-inline-start:8px}
/* ---- buttons ---- */
.gbtn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:0 20px;border-radius:12px;background:var(--ru);color:#fff!important;font-weight:700;font-size:15px;text-decoration:none;border:0;cursor:pointer;font-family:inherit;box-shadow:0 1px 0 rgba(255,255,255,.18) inset,0 6px 16px rgba(31,63,191,.28);transition:transform .15s var(--ease),box-shadow .15s,background .15s;white-space:nowrap}
.gbtn:hover{background:var(--rd);transform:translateY(-1px);box-shadow:0 1px 0 rgba(255,255,255,.18) inset,0 10px 24px rgba(31,63,191,.34)}.gbtn:active{transform:none}
.gbtn.sm{min-height:38px;padding:0 14px;font-size:14px;border-radius:10px}.gbtn.lg{min-height:54px;padding:0 28px;font-size:17px;border-radius:14px}
.gbtn.ghost{background:var(--tn);color:var(--ru)!important;box-shadow:none}.gbtn.ghost:hover{background:#e2e8fa}
.gbtn.white{background:#fff;color:var(--rd)!important;box-shadow:0 10px 30px rgba(0,0,0,.25)}.gbtn.white:hover{background:#f2f5ff}
.gbtn.line{background:rgba(255,255,255,.06);color:#fff!important;box-shadow:inset 0 0 0 1.5px rgba(255,255,255,.35)}.gbtn.line:hover{background:rgba(255,255,255,.14)}
/* ---- global header ---- */
header.gh{position:sticky;top:0;z-index:100;display:block;padding:0;background:rgba(255,255,255,.86);-webkit-backdrop-filter:saturate(180%) blur(14px);backdrop-filter:saturate(180%) blur(14px);border-bottom:1px solid rgba(15,22,48,.07)}
.gh-in{max-width:1200px;margin:0 auto;height:66px;padding:0 24px;display:flex;align-items:center;gap:6px}
.gh-logo{display:flex;align-items:center;margin-inline-end:4px}.gh-logo img{height:30px;width:auto;display:block}
.gh-site{font-weight:700;font-size:13px;color:var(--ru);background:var(--tn);border-radius:999px;padding:3px 10px;text-decoration:none;margin-inline-end:10px}
.gh-panel{display:flex;align-items:center;flex:1}.gh-nav{display:flex;align-items:center;gap:2px;margin-inline-start:14px}
.gh nav a{margin:0}
.gh-link{display:inline-flex;align-items:center;gap:4px;height:40px;padding:0 14px;border-radius:10px;color:#2b3557;font-weight:600;font-size:15px;text-decoration:none;background:none;border:0;cursor:pointer;font-family:inherit;transition:background .15s,color .15s}
.gh-link:hover,.gh-dd.open>.gh-link{background:var(--tn);color:var(--ru)}.gh-link.on{color:var(--ru)}
.gh-link .chev{width:16px;height:16px;transition:transform .2s var(--ease)}.gh-dd.open .chev{transform:rotate(180deg)}
.gh-dd{position:relative}
.mega{position:absolute;top:calc(100% + 10px);inset-inline-start:-12px;width:min(760px,calc(100vw - 48px));display:grid;grid-template-columns:1fr 220px;background:#fff;border-radius:18px;box-shadow:var(--sh3),0 0 0 1px rgba(15,22,48,.06);overflow:hidden;opacity:0;visibility:hidden;transform:translateY(-6px) scale(.985);transform-origin:top right;transition:opacity .18s var(--ease),transform .18s var(--ease),visibility .18s}
.gh-dd.open .mega,.gh-dd.open .gh-menu{opacity:1;visibility:visible;transform:none}
.mega-grid{display:grid;grid-template-columns:1fr 1fr;gap:4px;padding:14px}
.mi{display:flex;gap:12px;align-items:flex-start;padding:12px;border-radius:12px;text-decoration:none;color:var(--ink);transition:background .15s}
.mi:hover{background:var(--tn2)}.mi:hover .mi-ic{background:var(--ru);color:#fff;transform:scale(1.05)}
.mi-ic{width:40px;height:40px;border-radius:11px;display:grid;place-items:center;background:var(--tn);color:var(--ru);flex:none;transition:all .2s var(--ease)}
.mi b{display:block;font-size:15px;line-height:1.3}.mi small{display:block;color:var(--mu);font-size:13px;line-height:1.4;margin-top:2px}
.mega-side{background:linear-gradient(160deg,var(--tn2),#e9eefc);padding:20px;display:flex;flex-direction:column;gap:6px;border-inline-start:1px solid var(--ln)}
.mega-k{font-size:12px;font-weight:700;color:var(--mu);margin:0 0 6px;letter-spacing:.02em}
.mega-side a{display:flex;align-items:center;justify-content:space-between;color:var(--rd);text-decoration:none;font-weight:600;font-size:14px;padding:8px 0}.mega-side a .ic{width:16px;height:16px;transition:transform .15s}.mega-side a:hover .ic{transform:translateX(-3px)}
.gh-act{display:flex;align-items:center;gap:8px;margin-inline-start:auto}
.gh-login{color:#2b3557;font-weight:600;text-decoration:none;padding:8px 12px;border-radius:10px;font-size:15px}.gh-login:hover{background:var(--tn);color:var(--ru)}
.gh-av{width:38px;height:38px;border-radius:50%;border:0;cursor:pointer;background:linear-gradient(135deg,var(--r),var(--rd));color:#fff;font:700 16px/1 inherit;font-family:inherit;box-shadow:0 0 0 3px #fff,0 0 0 4px var(--bdr)}
.gh-menu{position:absolute;top:calc(100% + 10px);inset-inline-end:0;min-width:240px;background:#fff;border-radius:14px;box-shadow:var(--sh3),0 0 0 1px rgba(15,22,48,.06);padding:6px;opacity:0;visibility:hidden;transform:translateY(-6px);transition:all .18s var(--ease)}
.gh-mh{padding:10px 12px 12px;border-bottom:1px solid var(--ln);margin-bottom:4px}.gh-mh b{display:block}.gh-mh small{color:var(--mu);font-size:12px}
.gh-menu a,.gh-menu button{display:flex;align-items:center;gap:10px;width:100%;padding:10px 12px;border-radius:9px;color:var(--ink);text-decoration:none;font:600 14px inherit;font-family:inherit;background:none;border:0;cursor:pointer;margin:0}
.gh-menu a:hover,.gh-menu button:hover{background:var(--tn2)}.gh-menu .ic{width:18px;height:18px;color:var(--mu)}.gh-menu form{margin:0}
.gh-burger{display:none;width:42px;height:42px;border-radius:11px;border:0;background:var(--tn);color:var(--rd);cursor:pointer;place-items:center}.gh-burger .c{display:none}
.gh-mauth{display:none}
@media (max-width:900px){
 .gh-in{height:60px;padding:0 16px}.gh-burger{display:grid}.gh-login{display:none}
 .gh-panel{position:fixed;inset:60px 0 0 0;background:#fff;flex-direction:column;align-items:stretch;padding:12px 16px 28px;overflow:auto;opacity:0;visibility:hidden;transform:translateY(-8px);transition:all .2s var(--ease)}
 .gh.navopen .gh-panel{opacity:1;visibility:visible;transform:none}.gh.navopen .gh-burger .o{display:none}.gh.navopen .gh-burger .c{display:block}
 .gh-nav{flex-direction:column;align-items:stretch;margin:0;gap:0}.gh-link{height:54px;font-size:17px;justify-content:space-between;border-bottom:1px solid var(--ln);border-radius:0;padding:0 4px}
 .gh-link:hover,.gh-dd.open>.gh-link{background:none}
 .mega{position:static;width:auto;display:none;grid-template-columns:1fr;box-shadow:none;opacity:1;visibility:visible;transform:none;border-radius:0}.gh-dd.open .mega{display:block}
 .mega-grid{grid-template-columns:1fr;padding:6px 0}.mega-side{display:none}.mi{padding:10px 4px}
 .gh-mauth{display:grid;gap:10px;margin-top:20px}.gh-mauth .gbtn{min-height:50px}
 .gh-act .gbtn.sm{padding:0 12px}
}
@media (max-width:380px){.gh-site{display:none}}
/* ---- footer ---- */
footer.gf{background:var(--nv2);color:#b8c2e0;padding:56px 24px 28px;text-align:start;font-size:14px;margin-top:0}
.gf-in{max-width:1200px;margin:0 auto;display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:32px}
.gf-brand img{height:36px;width:auto}.gf-brand p{max-width:300px;line-height:1.7;margin:14px 0 0;color:#93a0c8}
.gf h3{color:#fff;font-size:14px;margin:4px 0 14px;font-weight:700}
.gf nav{display:flex;flex-direction:column;gap:10px}.gf nav a{color:#b8c2e0;text-decoration:none;margin:0}.gf nav a:hover{color:#fff}
.gf-bot{max-width:1200px;margin:40px auto 0;padding-top:20px;border-top:1px solid rgba(255,255,255,.08);display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;font-size:13px;color:#7d89b3}.gf-bot a{color:#b8c2e0}
@media (max-width:760px){.gf-in{grid-template-columns:1fr 1fr}.gf-brand{grid-column:1/-1}footer.gf{padding:44px 20px 24px}}
/* ---- reveal ---- */
.js .rv{opacity:0;transform:translateY(18px);transition:opacity .7s var(--ease),transform .7s var(--ease)}.js .rv.in{opacity:1;transform:none}
.js .rv.d1{transition-delay:.08s}.js .rv.d2{transition-delay:.16s}.js .rv.d3{transition-delay:.24s}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important}.js .rv{opacity:1;transform:none}}
/* ---- demo certificate (illustration, sample data) ---- */
.hv{position:relative;min-height:440px;display:grid;place-items:center;perspective:1400px}
.demo{position:relative;width:min(400px,100%);background:#fff;border-radius:22px;padding:22px;color:var(--ink);box-shadow:0 40px 80px rgba(3,10,40,.45),0 0 0 1px rgba(255,255,255,.4);transform:rotateY(-8deg) rotateX(4deg);transition:transform .6s var(--ease);animation:fl 7s ease-in-out infinite}
.hv:hover .demo{transform:rotateY(0) rotateX(0)}
@keyframes fl{50%{translate:0 -8px}}
.demo-h{display:flex;align-items:center;gap:10px;padding-bottom:14px;border-bottom:1px dashed var(--bdr)}.demo-h img{width:34px;height:34px}.demo-h b{font-size:16px;display:block;line-height:1.2}.demo-h small{color:var(--mu);font-size:12px}
.demo-tag{margin-inline-start:auto;font-size:11px;font-weight:700;color:#8A5D00;background:#FFF4DC;border-radius:999px;padding:3px 9px}
.demo-f{display:flex;align-items:center;gap:10px;margin:16px 0 12px;font-weight:600;font-size:14px}.demo-f .fi{width:36px;height:42px;border-radius:7px;background:linear-gradient(160deg,#f1f4ff,#dfe6fb);display:grid;place-items:center;color:var(--ru);font-size:10px;font-weight:800}
.demo-l{font-size:11.5px;color:var(--mu);font-weight:600;margin-bottom:5px}
.demo-hash{display:block;direction:ltr;text-align:left;font-family:"IBM Plex Mono",ui-monospace,monospace;font-size:12px;line-height:1.55;background:var(--tn2);border:1px solid var(--ln);border-radius:10px;padding:10px 12px;color:var(--rd);word-break:break-all;min-height:60px}
.demo-rows{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:12px}.demo-rows div{background:var(--tn2);border-radius:10px;padding:8px 10px;font-size:12px;color:var(--mu)}.demo-rows b{display:block;color:var(--ink);font-size:13.5px}
.demo-st{display:flex;align-items:center;gap:10px;margin-top:14px;padding:12px;border-radius:12px;background:#FFF8E6;color:#8A5D00;font-weight:700;font-size:14px;transition:all .4s var(--ease)}
.demo-st .sp{width:16px;height:16px;border-radius:50%;border:2px solid currentColor;border-inline-end-color:transparent;animation:sp .9s linear infinite}.demo-st .ok{display:none}
.demo.done .demo-st{background:var(--okb);color:var(--ok)}.demo.done .demo-st .sp{display:none}.demo.done .demo-st .ok{display:inline}.demo-st .t2{display:none}.demo.done .demo-st .t1{display:none}.demo.done .demo-st .t2{display:inline}
.vbadge{position:absolute;inset-inline-start:-18px;bottom:-16px;display:flex;align-items:center;gap:8px;background:#0F7A45;color:#fff;font-weight:700;font-size:13px;padding:9px 14px 9px 16px;border-radius:999px;box-shadow:0 14px 30px rgba(15,122,69,.45);transform:scale(.6);opacity:0;transition:all .45s cubic-bezier(.2,1.4,.3,1)}
.demo.done .vbadge{transform:none;opacity:1}.vbadge .ic{width:16px;height:16px;stroke-width:2.6}
.flc{position:absolute;background:rgba(255,255,255,.1);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.18);color:#fff;border-radius:16px;padding:12px 14px;display:flex;align-items:center;gap:10px;font-size:13px;box-shadow:0 20px 40px rgba(0,0,0,.25);animation:fl 8s ease-in-out infinite}
.flc .ic{width:30px;height:30px;padding:6px;border-radius:9px;background:rgba(255,255,255,.16)}.flc b{display:block;font-size:13.5px}.flc small{color:#c9d4f5}
.flc{z-index:3}.flc.a{top:-44px;inset-inline-end:0;animation-delay:-2s}.flc.b{bottom:-34px;inset-inline-start:-18px;animation-delay:-4s}
@keyframes sp{to{transform:rotate(360deg)}}
@media(max-width:900px){.hv{min-height:0;padding:10px 0 30px}.demo{transform:none}.flc{display:none}.vbadge{inset-inline-start:12px}}
/* menu-fix: fixed drawer must not be trapped by header backdrop-filter; hover bridge */
.gh-dd .mega::before{content:"";position:absolute;inset-inline:0;top:-14px;height:14px}
.mega{overflow:visible}.mega-grid{border-radius:18px 0 0 18px}.mega-side{border-radius:0 18px 18px 0}
@media (max-width:900px){
 header.gh.navopen{-webkit-backdrop-filter:none;backdrop-filter:none;background:#fff}
 .gh-panel{z-index:99;height:calc(100vh - 60px);height:calc(100dvh - 60px);overscroll-behavior:contain;-webkit-overflow-scrolling:touch}
 .gh-dd .mega::before{display:none}
}
/* iOS touch: no sticky hover, instant taps */
.gh button,.gh a{touch-action:manipulation;-webkit-tap-highlight-color:transparent;cursor:pointer}
@media (hover:none){.gh-link:hover{background:none;color:inherit}.gh-dd.open>.gh-link{background:var(--tn);color:var(--ru)}}