:root{--navy:#0d2c5e;--red:#ef233c;--text:#172033;--muted:#667085;--line:#e5eaf0;--soft:#f7f9fc;--white:#fff;--container:1040px;--shadow:0 18px 55px rgba(13,44,94,.10)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;color:var(--text);background:var(--soft);line-height:1.6;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}.container{width:min(calc(100% - 36px),var(--container));margin-inline:auto}.site-header{background:#fff;border-bottom:1px solid var(--line)}.nav{min-height:72px;display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{display:flex;align-items:center;gap:10px;color:var(--navy);font-weight:900;font-size:1.2rem}.brand b{color:var(--red)}.mark{width:34px;height:34px;border-radius:10px;background:var(--red);color:#fff;display:grid;place-items:center;font-size:1.25rem}.nav-actions{display:flex;gap:10px;align-items:center}.link{font-size:.88rem;font-weight:750;color:#31557f}.button{min-height:44px;padding:0 17px;border-radius:9px;background:var(--red);color:#fff;display:inline-flex;align-items:center;justify-content:center;font-weight:850}.hero{padding:58px 0 30px}.crumb{display:flex;gap:7px;flex-wrap:wrap;color:#718096;font-size:.8rem;margin-bottom:18px}.crumb a{color:#1558a7}.kicker{color:var(--red);font-weight:900;font-size:.72rem;letter-spacing:.12em}.hero h1{margin:7px 0 12px;color:var(--navy);font-size:clamp(2rem,5vw,3.55rem);line-height:1.08;letter-spacing:-.035em}.lead{margin:0;color:var(--muted);font-size:1rem;max-width:750px}.content{padding:15px 0 70px}.video-shell{background:#08101e;border-radius:18px;padding:10px;box-shadow:var(--shadow)}.video-frame{position:relative;aspect-ratio:16/9;overflow:hidden;border-radius:12px;background:#030712}.video-frame iframe{position:absolute;inset:0;width:100%;height:100%;border:0}.tutorial-card{margin-top:18px;background:#fff;border:1px solid var(--line);border-radius:15px;padding:25px}.tutorial-card h2{color:var(--navy);margin:0 0 8px;font-size:1.25rem}.tutorial-card p{color:var(--muted);margin:0}.pager{display:grid;grid-template-columns:1fr auto 1fr;gap:12px;align-items:stretch;margin-top:18px}.pager a{min-height:62px;padding:12px 15px;background:#fff;border:1px solid var(--line);border-radius:11px;display:flex;flex-direction:column;justify-content:center;font-size:.75rem;color:var(--muted)}.pager a strong{color:var(--navy);font-size:.85rem}.pager .next{text-align:right}.pager .all{align-items:center;text-align:center;color:#1558a7;font-weight:850}.help-hero{text-align:center;max-width:760px;margin-inline:auto}.help-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;padding:10px 0 70px}.help-card{display:grid;grid-template-columns:44px 42px 1fr;gap:12px;align-items:center;background:#fff;border:1px solid var(--line);border-radius:13px;padding:15px;min-height:82px}.help-card:hover{border-color:#b9cde4;box-shadow:0 8px 24px rgba(13,44,94,.07)}.number{color:#8b98aa;font-weight:900;font-size:.75rem}.play{width:40px;height:40px;border-radius:50%;display:grid;place-items:center;background:#fff0f2;color:var(--red);font-size:.7rem;padding-left:2px}.help-card strong{color:var(--navy);font-size:.9rem;line-height:1.35}.footer{background:#fff;border-top:1px solid var(--line);padding:28px 0;color:#7b8797;font-size:.78rem}.footer .container{display:flex;justify-content:space-between;gap:20px}.noscript{padding:16px;background:#fff4e5;color:#7a4100;border-radius:10px;margin-bottom:15px}
@media(max-width:700px){.nav{min-height:64px}.brand{font-size:1rem}.mark{width:30px;height:30px}.nav-actions .link{display:none}.hero{padding-top:38px}.help-grid{grid-template-columns:1fr}.pager{grid-template-columns:1fr 1fr}.pager .all{grid-column:1/-1;grid-row:1}.tutorial-card{padding:20px}.footer .container{flex-direction:column}.help-card{grid-template-columns:32px 40px 1fr;padding:13px}.help-card strong{font-size:.86rem}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
.youtube-fallback{display:flex;justify-content:flex-end;margin-top:13px}.youtube-fallback .button{box-shadow:0 8px 18px rgba(239,35,60,.14)}