:root{color-scheme:light;--ink:#18231c;--muted:#59655d;--line:#d8e0da;--soft:#f4f7f4;--surface:#fff;--accent:#2f6f46;--accent-dark:#245737;--accent-soft:#e7f1e9;--shadow:0 24px 65px rgba(25,45,31,.12);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:#f7f9f7;color:var(--ink)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;min-height:100vh;background:linear-gradient(180deg,#fbfcfb 0,#f4f7f4 58%,#fff 100%);color:var(--ink)}a{color:inherit}a:focus-visible{outline:3px solid rgba(47,111,70,.35);outline-offset:3px;border-radius:7px}.skip-link{position:fixed;left:.75rem;top:.75rem;z-index:20;transform:translateY(-160%);padding:.55rem .8rem;border-radius:8px;background:#fff;border:1px solid var(--line);font-weight:700}.skip-link:focus{transform:none}.landing-header{position:sticky;top:0;z-index:10;display:flex;align-items:center;justify-content:space-between;gap:1rem;max-width:1220px;margin:0 auto;padding:1rem clamp(1rem,3vw,2.2rem);background:rgba(251,252,251,.93);backdrop-filter:blur(14px);border-bottom:1px solid rgba(216,224,218,.78)}.landing-brand{display:inline-flex;align-items:center;gap:.58rem;text-decoration:none;font-weight:820;letter-spacing:-.02em}.brand-mark{display:grid;place-items:center;width:2.15rem;height:2.15rem;border-radius:10px;background:var(--ink);color:#fff;font-size:1.35rem}.landing-nav{display:flex;align-items:center;gap:clamp(.55rem,1.5vw,1.25rem);font-size:.9rem}.landing-nav a{text-decoration:none;color:var(--muted);font-weight:650}.landing-nav a:hover{color:var(--ink)}.landing-nav .nav-enter{padding:.58rem .82rem;border-radius:9px;background:var(--ink);color:#fff}.landing-nav .nav-enter:hover{background:#0e1711;color:#fff}main{max-width:1220px;margin:0 auto;padding:0 clamp(1rem,3vw,2.2rem) 4rem}.hero{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(300px,.9fr);align-items:center;gap:clamp(2rem,6vw,5rem);min-height:min(760px,calc(100vh - 70px));padding:clamp(3.5rem,8vw,7rem) 0}.eyebrow{margin:0 0 .85rem;color:var(--accent);font-size:.77rem;font-weight:820;letter-spacing:.13em;text-transform:uppercase}.hero h1,.landing-section h2,.landing-cta h2{margin:0;letter-spacing:-.045em;line-height:1.04}.hero h1{max-width:830px;font-size:clamp(2.55rem,6.1vw,5.6rem)}.hero-lead{max-width:760px;margin:1.35rem 0 0;color:var(--muted);font-size:clamp(1.02rem,1.65vw,1.28rem);line-height:1.65}.hero-actions{display:flex;flex-wrap:wrap;gap:.72rem;margin-top:1.8rem}.primary-action,.secondary-action{display:inline-flex;align-items:center;justify-content:center;min-height:3rem;padding:.72rem 1rem;border-radius:10px;text-decoration:none;font-weight:790}.primary-action{background:var(--accent);color:#fff;box-shadow:0 12px 28px rgba(47,111,70,.2)}.primary-action:hover{background:var(--accent-dark)}.secondary-action{border:1px solid var(--line);background:#fff;color:var(--ink)}.secondary-action:hover{background:var(--soft)}.hero-note{margin:.85rem 0 0;color:#6f7a72;font-size:.84rem}.hero-board{justify-self:end;width:min(100%,452px);margin:0;border:1px solid #d7dbd6;border-radius:14px;overflow:hidden;background:#fff;box-shadow:0 24px 58px rgba(31,38,33,.13)}.hero-position-meta{display:flex;align-items:end;justify-content:space-between;gap:1rem;margin:0;padding:1rem 1rem .86rem;border-bottom:1px solid #eceeea;background:linear-gradient(180deg,#fff,#fbfcfb)}.hero-position-meta>span:first-child{display:grid;gap:.12rem}.hero-position-meta small{color:#778078;font-size:.66rem;font-weight:780;letter-spacing:.11em;text-transform:uppercase}.hero-position-meta strong{font-size:1.02rem;letter-spacing:-.012em}.position-sequence{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;color:#5f665f;font-size:.76rem;font-weight:760;white-space:nowrap}.mini-board{display:grid;grid-template-columns:repeat(8,minmax(0,1fr));grid-template-rows:repeat(8,minmax(0,1fr));width:calc(100% - 2rem);aspect-ratio:1/1;margin:1rem;border:4px solid #5f4b3b;border-radius:2px;overflow:hidden;background:#f0d9b5;box-shadow:0 8px 22px rgba(46,34,24,.18),inset 0 0 0 1px rgba(255,255,255,.18)}.landing-square{position:relative;display:grid;place-items:center;min-width:0;min-height:0;overflow:hidden}.landing-square.light{background:#f0d9b5}.landing-square.dark{background:#b58863}.landing-square[data-last-move]{box-shadow:inset 0 0 0 999px rgba(226,196,71,.20)}.landing-square img{position:relative;z-index:2;display:block;width:88%;height:88%;object-fit:contain;user-select:none;-webkit-user-drag:none;filter:drop-shadow(0 1px 1px rgba(0,0,0,.10))}.landing-square[data-rank]::before,.landing-square[data-file]::after{position:absolute;z-index:3;font-size:clamp(.42rem,1vw,.59rem);font-weight:820;line-height:1;pointer-events:none;opacity:.82}.landing-square[data-rank]::before{content:attr(data-rank);top:.17rem;left:.19rem}.landing-square[data-file]::after{content:attr(data-file);right:.19rem;bottom:.16rem}.landing-square.light[data-rank]::before,.landing-square.light[data-file]::after{color:#8b6547}.landing-square.dark[data-rank]::before,.landing-square.dark[data-file]::after{color:#f2ddbd}.hero-board-caption{display:flex;align-items:center;gap:.58rem;margin:0;padding:.78rem 1rem .92rem;border-top:1px solid #eceeea;background:#fbfcfb;color:#616861;font-size:.77rem;line-height:1.45}.position-status-dot{width:.48rem;height:.48rem;flex:0 0 .48rem;border-radius:50%;background:#5f4b3b;box-shadow:0 0 0 3px #eee8e1}.landing-section{padding:clamp(3.5rem,7vw,6.4rem) 0;border-top:1px solid var(--line)}.section-heading{max-width:820px}.landing-section h2,.landing-cta h2{font-size:clamp(2rem,4vw,3.5rem)}.section-heading>p:last-child,.compact-section>div>p:last-child{color:var(--muted);font-size:1rem;line-height:1.7}.feature-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1rem;margin-top:2.2rem}.feature-grid article{min-height:225px;padding:1.25rem;border:1px solid var(--line);border-radius:15px;background:rgba(255,255,255,.85)}.feature-icon{display:grid;place-items:center;width:2.45rem;height:2.45rem;border-radius:9px;background:var(--accent-soft);color:var(--accent-dark);font-weight:900}.feature-grid h3{margin:1rem 0 .45rem;font-size:1.08rem}.feature-grid h3 a{text-decoration:none}.feature-grid h3 a:hover{text-decoration:underline}.feature-grid p{margin:0;color:var(--muted);font-size:.92rem;line-height:1.6}.workflow-section{display:grid;grid-template-columns:minmax(0,.9fr) minmax(360px,1.1fr);gap:clamp(2rem,6vw,5rem)}.workflow-list{display:grid;gap:.72rem;margin:0;padding:0;list-style:none}.workflow-list li{display:grid;grid-template-columns:2.3rem minmax(0,1fr);gap:.85rem;padding:1rem;border:1px solid var(--line);border-radius:13px;background:#fff}.workflow-list li>span{display:grid;place-items:center;width:2.3rem;height:2.3rem;border-radius:50%;background:var(--ink);color:#fff;font-size:.78rem;font-weight:850}.workflow-list strong{display:block;margin:.08rem 0 .32rem}.workflow-list p{margin:0;color:var(--muted);font-size:.88rem;line-height:1.55}.compact-section{display:flex;align-items:end;justify-content:space-between;gap:2rem}.compact-section>div{max-width:760px}.landing-cta{display:flex;align-items:center;justify-content:space-between;gap:2rem;margin:0 0 2rem;padding:clamp(1.4rem,4vw,2.3rem);border-radius:20px;background:var(--ink);color:#fff}.landing-cta .eyebrow{color:#9fd4ad}.landing-cta h2{max-width:760px;font-size:clamp(1.75rem,3.4vw,3rem)}.landing-cta .primary-action{flex:none;background:#fff;color:var(--ink);box-shadow:none}.landing-cta .primary-action:hover{background:#edf2ed}.landing-footer{display:flex;justify-content:space-between;gap:1rem;max-width:1220px;margin:0 auto;padding:1.4rem clamp(1rem,3vw,2.2rem) 2.2rem;border-top:1px solid var(--line);color:var(--muted);font-size:.82rem}.landing-footer>span{font-weight:780;color:var(--ink)}.landing-footer nav{display:flex;flex-wrap:wrap;gap:1rem}.landing-footer a{text-decoration:none}.landing-footer a:hover{text-decoration:underline}
@media(max-width:850px){.landing-header{position:relative}.landing-nav a:not(.nav-enter){display:none}.hero{grid-template-columns:1fr;min-height:0;padding-top:3.4rem}.hero-board{justify-self:start;width:min(88vw,460px)}.feature-grid{grid-template-columns:1fr 1fr}.workflow-section{grid-template-columns:1fr}.compact-section,.landing-cta{align-items:flex-start;flex-direction:column}.landing-cta .primary-action{width:100%}}
@media(max-width:560px){.landing-header{padding:.75rem 1rem}.landing-brand{font-size:.93rem}.brand-mark{width:1.9rem;height:1.9rem;font-size:1.15rem}.landing-nav .nav-enter{padding:.5rem .68rem;font-size:.82rem}.hero{padding:2.7rem 0 3.6rem}.hero h1{font-size:clamp(2.35rem,13vw,3.7rem)}.hero-board{width:100%}.feature-grid{grid-template-columns:1fr}.feature-grid article{min-height:0}.landing-section{padding:3.3rem 0}.landing-footer{flex-direction:column}.landing-cta{border-radius:15px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

/* Public Help is intentionally isolated from the trainer workspace. */
.public-help-main{padding-top:0}.public-help-hero{max-width:930px;padding:clamp(3.5rem,7vw,6rem) 0 clamp(2.6rem,5vw,4.5rem)}.public-help-hero h1{margin:0;max-width:900px;font-size:clamp(2.45rem,5vw,4.7rem);line-height:1.04;letter-spacing:-.045em}.public-help-hero>p:not(.eyebrow){max-width:800px;margin:1.2rem 0 0;color:var(--muted);font-size:clamp(1rem,1.6vw,1.2rem);line-height:1.7}.public-help-layout{display:grid;grid-template-columns:250px minmax(0,1fr);gap:clamp(2rem,5vw,4.2rem);align-items:start;padding:0 0 clamp(4rem,8vw,7rem);border-top:1px solid var(--line)}.public-help-toc{position:sticky;top:5.4rem;max-height:calc(100vh - 6.4rem);overflow:auto;padding:1.4rem 0}.public-help-toc>strong{display:block;margin-bottom:.65rem;font-size:.78rem;letter-spacing:.1em;text-transform:uppercase}.public-help-toc nav{display:grid;gap:.08rem}.public-help-toc a{padding:.42rem .55rem;border-radius:8px;color:var(--muted);font-size:.86rem;font-weight:650;text-decoration:none}.public-help-toc a:hover{background:var(--accent-soft);color:var(--accent-dark)}.public-help-content{min-width:0}.public-help-content>section{scroll-margin-top:5.7rem;padding:clamp(2.7rem,5vw,4.5rem) 0;border-bottom:1px solid var(--line)}.public-help-content>section:last-child{border-bottom:0}.public-help-content h2{margin:0 0 1.1rem;font-size:clamp(1.75rem,3.2vw,2.65rem);line-height:1.12;letter-spacing:-.035em}.public-help-content h3{margin:1.65rem 0 .55rem;font-size:1.05rem}.public-help-content p,.public-help-content li,.public-help-content dd{color:var(--muted);line-height:1.72}.public-help-content p{margin:.72rem 0}.public-help-content ul,.public-help-content ol{padding-left:1.3rem}.public-help-content li+li{margin-top:.42rem}.public-help-content dl{display:grid;gap:.72rem;margin:1rem 0}.public-help-content dl>div{display:grid;grid-template-columns:minmax(115px,.28fr) minmax(0,1fr);gap:1rem;padding:.9rem 1rem;border:1px solid var(--line);border-radius:11px;background:#fff}.public-help-content dt{font-weight:800;color:var(--ink)}.public-help-content dd{margin:0}.public-help-table-wrap{max-width:100%;overflow-x:auto;margin:1rem 0;border:1px solid var(--line);border-radius:12px;background:#fff}.public-help-content table{width:100%;border-collapse:collapse;min-width:620px}.public-help-content th,.public-help-content td{padding:.8rem .9rem;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}.public-help-content th{background:var(--soft);font-size:.82rem}.public-help-content td:first-child{font-weight:800;color:var(--ink);white-space:nowrap}.public-help-content tbody tr:last-child td{border-bottom:0}.public-help-content details{margin:.75rem 0;padding:.95rem 1rem;border:1px solid var(--line);border-radius:11px;background:#fff}.public-help-content summary{cursor:pointer;font-weight:800}.public-help-content details p{margin:.7rem 0 0}.public-help-cta{margin-bottom:2rem}
@media(max-width:850px){.public-help-layout{grid-template-columns:1fr;gap:0}.public-help-toc{position:relative;top:auto;max-height:none;padding:1.2rem 0 0}.public-help-toc nav{grid-template-columns:repeat(2,minmax(0,1fr));gap:.15rem .5rem}.public-help-content>section{scroll-margin-top:1rem}.public-help-content dl>div{grid-template-columns:1fr;gap:.25rem}}
@media(max-width:560px){.public-help-hero{padding:2.8rem 0 2.5rem}.public-help-toc nav{grid-template-columns:1fr}.public-help-content>section{padding:2.7rem 0}.public-help-content dl>div{padding:.8rem}.public-help-cta{margin-top:.5rem}}