body{--acc:#14a35a;--acc-ink:#fff}
body[data-course="chem"]{--acc:#6a5ae0}
@media (prefers-color-scheme:dark){body{--acc:#3ddc84;--acc-ink:#06110d}body[data-course="chem"]{--acc:#9a8cff;--acc-ink:#0e0f11}}
[hidden]{display:none!important}
.bd-hero{background:linear-gradient(180deg,#06110d,#0b2a1f);color:#fff;padding-block:64px 72px}
body[data-course="chem"] .bd-hero{background:linear-gradient(180deg,#0e0b24,#241a5a)}
.bd-hero .wrap{display:flex;flex-direction:column;align-items:center}
.eyebrow{letter-spacing:.16em;text-transform:uppercase;font-size:.78rem;color:#7bf5b2;font-weight:600;margin-bottom:10px}
body[data-course="chem"] .eyebrow{color:#c3b9ff}
.bd-hero .lede{color:#b9cfc4;margin-top:14px;max-width:56ch;font-size:1.1rem}
body[data-course="chem"] .bd-hero .lede{color:#cfc9ee}
.bd-hero .btn{background:#fff;color:#06110d;border-color:#fff}
.bd-hero .btn.light,.bd-final .btn.light{background:transparent;color:#fff;border-color:rgba(255,255,255,.45)}
.bd-hero .btn.light:hover{background:rgba(255,255,255,.12)}
.bd-hero .actions{display:flex;gap:12px;flex-wrap:wrap;justify-content:center;margin-top:30px}
.bd-tabs{margin-top:30px}
.bd-tabs .tab{color:#b9cfc4;font-size:1.02rem;padding:10px 20px}
.bd-tabs .tab[aria-pressed="true"]{color:#fff;border-bottom-color:#fff}
.bd-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:rgba(255,255,255,.18);border:1px solid rgba(255,255,255,.18);border-radius:12px;overflow:hidden;margin-top:34px;width:100%;max-width:820px}
.bd-stats div{background:rgba(255,255,255,.06);padding:18px 12px;display:flex;flex-direction:column;gap:2px}
.bd-stats b{font-size:2rem;font-weight:500;line-height:1.1}
.bd-stats span{font-size:.85rem;color:#b9cfc4}
.bd-wrap{display:flex;flex-direction:column;align-items:center}
.bd-units{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;width:100%;max-width:900px;margin-top:30px}
.bd-u{display:flex;flex-direction:column;align-items:flex-start;gap:2px;text-align:left;padding:14px 16px;border:1px solid var(--line);border-radius:10px;background:var(--bg);color:var(--ink);font:inherit;cursor:pointer;border-top:3px solid var(--line);transition:transform .2s,border-color .2s}
.alt .bd-u{background:var(--panel)}
.bd-u:hover{transform:translateY(-2px);border-top-color:var(--acc)}
.bd-u[aria-pressed="true"]{border-color:var(--acc);border-top-color:var(--acc);box-shadow:0 0 0 1px var(--acc)}
.bd-u .n{font-size:.72rem;letter-spacing:.14em;text-transform:uppercase;color:var(--acc);font-weight:600}
.bd-u .t{font-weight:500;font-size:1.05rem;line-height:1.25}
.bd-u .m{font-size:.85rem;color:var(--muted)}
.bd-detail{width:100%;max-width:900px;margin-top:18px;border:1px solid var(--line);border-radius:14px;background:var(--panel);padding:26px 28px;text-align:left}
.bd-detail h3{font-size:1.6rem}
.bd-chips{display:flex;flex-wrap:wrap;gap:8px;margin:12px 0 4px}
.bd-chips span{padding:4px 12px;border-radius:999px;border:1px solid var(--line);background:var(--bg);font-size:.85rem;color:var(--muted)}
.bd-cols{display:grid;grid-template-columns:1.2fr 1fr;gap:28px;margin-top:16px}
.bd-detail h4{font-size:.8rem;letter-spacing:.14em;text-transform:uppercase;color:var(--muted);margin-bottom:8px;font-weight:600}
.bd-detail ul{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:8px}
.bd-detail li{padding-left:18px;position:relative;color:var(--ink)}
.bd-detail li::before{content:"";position:absolute;left:0;top:.62em;width:8px;height:8px;border-radius:2px;background:var(--acc)}
.bd-try a{display:block;padding:10px 14px;border:1px solid var(--line);border-radius:8px;background:var(--bg);text-decoration:none;margin-bottom:8px;font-weight:500}
.bd-try a:hover{border-color:var(--acc)}
.bd-try a small{display:block;font-weight:400;color:var(--muted);font-size:.8rem}
.bd-controls{display:flex;gap:18px;flex-wrap:wrap;align-items:center;justify-content:center;margin-top:26px}
.bd-controls label{display:flex;gap:10px;align-items:center;color:var(--muted)}
.bd-controls select{font:inherit;padding:8px 12px;border-radius:6px;border:2px solid var(--line);background:var(--bg);color:var(--ink)}
.bd-controls .tabs{margin-top:0}
.bd-week{display:grid;grid-template-columns:repeat(5,1fr);gap:10px;width:100%;max-width:1040px;margin-top:26px}
.bd-week.three{grid-template-columns:repeat(3,1fr);max-width:820px}
.bd-day{background:var(--bg);border:1px solid var(--line);border-top:3px solid var(--acc);border-radius:10px;padding:14px;text-align:left;display:flex;flex-direction:column;gap:8px;min-height:190px}
.bd-day h3{font-size:1rem;font-weight:600}
.bd-day p{color:var(--muted);font-size:.9rem}
.bd-pieces{display:flex;flex-wrap:wrap;gap:6px;margin-top:auto}
.bd-pieces span{font-size:.72rem;letter-spacing:.06em;text-transform:uppercase;padding:3px 8px;border-radius:5px;background:color-mix(in srgb,var(--acc) 16%,var(--bg));color:var(--ink);font-weight:600}
.bd-note{color:var(--muted);font-size:.92rem;margin-top:16px;max-width:70ch}
.bd-gallery{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;width:100%;max-width:1060px;margin-top:30px}
.bd-gallery.bd-three{grid-template-columns:repeat(3,1fr)}
.bd-gallery figure{margin:0;text-align:left}
.bd-gallery button{display:block;width:100%;padding:0;border:1px solid var(--line);border-radius:10px;overflow:hidden;background:var(--panel);cursor:zoom-in;transition:transform .2s,box-shadow .2s}
.bd-gallery button:hover{transform:translateY(-3px);box-shadow:0 10px 26px rgba(0,0,0,.15)}
.bd-gallery img{display:block;width:100%;height:auto}
.bd-gallery figcaption{margin-top:8px;font-size:.88rem;color:var(--muted);line-height:1.35}
.bd-gallery figcaption b{display:block;color:var(--ink);font-weight:600}
.bd-lb{position:fixed;inset:0;z-index:100;background:rgba(0,0,0,.86);display:flex;align-items:center;justify-content:center;padding:24px;cursor:zoom-out}
.bd-lb img{max-width:100%;max-height:100%;border-radius:8px;background:#fff}
.bd-lb-x{position:absolute;top:16px;right:16px;padding:8px 16px;border-radius:6px;border:0;background:#fff;color:#111;font:inherit;font-weight:500;cursor:pointer}
.bd-embed{width:100%;max-width:960px;margin-top:28px;border:1px solid var(--line);border-radius:14px;overflow:hidden;background:var(--bg)}
.bd-embed-bar{display:flex;justify-content:space-between;gap:12px;align-items:center;padding:10px 16px;background:var(--panel);border-bottom:1px solid var(--line);font-weight:500}
.bd-embed-bar a{font-size:.9rem;color:var(--muted)}
.bd-embed-body{height:min(640px,78vh);display:flex;align-items:center;justify-content:center;background:radial-gradient(circle at 50% 40%,color-mix(in srgb,var(--acc) 18%,var(--bg)),var(--bg) 70%)}
.bd-embed-body iframe{width:100%;height:100%;border:0;background:#fff}
.bd-tree,.bd-faq{width:100%;max-width:760px;margin-top:28px;text-align:left}
.bd-tree details,.bd-faq details{border:1px solid var(--line);border-radius:10px;background:var(--panel);padding:0;margin-bottom:8px}
.alt .bd-faq details{background:var(--bg)}
.bd-tree summary,.bd-faq summary{cursor:pointer;padding:14px 18px;font-weight:500;list-style:none;display:flex;gap:10px;align-items:baseline}
.bd-tree summary::-webkit-details-marker,.bd-faq summary::-webkit-details-marker{display:none}
.bd-tree summary::before,.bd-faq summary::before{content:"+";color:var(--acc);font-weight:700;width:14px}
.bd-tree details[open]>summary::before,.bd-faq details[open]>summary::before{content:"\2212"}
.bd-tree summary i{color:var(--muted);font-style:normal;font-weight:400;font-size:.9rem;margin-left:auto}
.bd-tree details details{margin:0 14px 8px;background:var(--bg)}
.bd-tree p,.bd-faq p{padding:0 18px 16px 42px;color:var(--muted)}
.bd-tree>details>summary{font-size:1.1rem}
.bd-final .wrap{display:flex;flex-direction:column;align-items:center}
.bd-final{background:linear-gradient(180deg,#0b2a1f,#06110d);color:#fff}
body[data-course="chem"] .bd-final{background:linear-gradient(180deg,#241a5a,#0e0b24)}
.bd-final .sub{color:#b9cfc4}
.bd-final .btn{background:#fff;color:#06110d;border-color:#fff}
.bd-final .actions{display:flex;gap:12px;flex-wrap:wrap;justify-content:center;margin-top:28px}
.bd-final .btn.light{background:transparent;color:#fff}
@media (max-width:900px){.bd-units{grid-template-columns:repeat(2,1fr)}.bd-week{grid-template-columns:repeat(2,1fr)}.bd-gallery{grid-template-columns:repeat(2,1fr)}.bd-cols{grid-template-columns:1fr}.bd-stats{grid-template-columns:repeat(2,1fr)}}
@media (max-width:560px){.bx-steps{top:73px}.bd-units{grid-template-columns:1fr}.bd-week,.bd-week.three{grid-template-columns:1fr}.bd-day{min-height:0}.bd-gallery,.bd-gallery.bd-three{grid-template-columns:1fr 1fr;gap:10px}.bd-detail{padding:20px 18px}.bd-controls .tabs{flex-wrap:wrap;justify-content:center}}
@media (prefers-reduced-motion:reduce){.bd-u,.bd-gallery button{transition:none}}
.bd-controls label{flex-wrap:wrap;justify-content:center;max-width:100%}
.bd-controls select{max-width:100%}
@media (max-width:560px){.nav .wrap{flex-wrap:wrap;justify-content:center;row-gap:6px}.bd-controls label{flex-direction:column;align-items:stretch;width:100%}.bd-controls select{width:100%}}

/* ---------- Unit 1 viewer ---------- */
a.cell.go{text-decoration:none;color:inherit;transition:border-color .2s,transform .2s}
a.cell.go:hover{border-top-color:var(--acc);transform:translateY(-2px)}
a.cell.go .gl{margin-top:auto;padding-top:10px;font-weight:500;color:var(--acc)}
a.cell.go .gl::after{content:" \2192"}
.u1-tabs{flex-wrap:wrap}
.u1-actpick{display:flex;flex-wrap:wrap;gap:4px;justify-content:center;margin-top:6px}
.u1-actpick .tab{padding:5px 14px;font-size:.9rem}
.u1-cap{color:var(--muted);max-width:68ch;margin-top:16px;font-size:.98rem}
.u1-view{display:flex;align-items:center;gap:12px;width:100%;max-width:980px;margin-top:18px}
.u1-fig{margin:0;flex:1;min-width:0;border:1px solid var(--line);border-radius:12px;background:var(--panel);overflow:hidden;min-height:200px;display:flex;align-items:center;justify-content:center}
.u1-fig img{display:block;width:100%;height:auto;max-height:82vh;object-fit:contain}
.u1-nav{flex:0 0 auto;width:46px;height:46px;border-radius:50%;border:1px solid var(--line);background:var(--bg);color:var(--ink);font-size:1.8rem;line-height:1;cursor:pointer;display:flex;align-items:center;justify-content:center;padding-bottom:4px}
.u1-nav:hover{border-color:var(--acc)}
.u1-count{margin-top:12px;color:var(--muted);font-weight:500;font-variant-numeric:tabular-nums}
.u1-strip{display:flex;gap:8px;overflow-x:auto;width:100%;max-width:980px;margin-top:12px;padding:6px 2px 10px;scroll-behavior:smooth}
.u1-strip button{flex:0 0 auto;width:112px;padding:0;border:2px solid var(--line);border-radius:6px;overflow:hidden;background:var(--panel);cursor:pointer}
.u1-strip button[aria-current="true"]{border-color:var(--acc)}
.u1-strip img{display:block;width:100%;height:auto;min-height:44px}
@media (max-width:640px){.u1-nav{width:38px;height:38px}.u1-view{gap:6px}.u1-strip button{width:84px}}

/* ---------- Look inside v2: pictures and interactive graphics ---------- */
.bx-art{display:block;position:relative;overflow:hidden;background:#050d0b}
.bx-art svg{display:block;width:100%;height:100%}
.bx-art *{transform-box:fill-box;transform-origin:center}
.bx-art .ca-spin,.bx-art .ca-sweep,.bx-art .ca-tilt,.bx-art .ca-stir{transform-box:view-box}
.bx-tag{position:absolute;left:8px;top:8px;z-index:2;padding:.2em .7em;border-radius:999px;background:var(--acc);color:var(--acc-ink);font-size:.72rem;font-weight:600;line-height:1.3;white-space:nowrap;box-shadow:0 4px 12px -3px rgba(0,0,0,.5)}
body[data-course="apes"] .bx-tag{background:#3ddc84;color:#06110d}
body[data-course="chem"] .bx-tag{background:#b9a4ff;color:#0e0b24}

/* hero */
.bd-hero{position:relative;overflow:hidden}
.bx-dots{position:absolute;inset:0;pointer-events:none;opacity:.5;background-image:radial-gradient(circle,#7bf5b2 1.2px,transparent 1.6px),radial-gradient(circle,#7bf5b2 1px,transparent 1.4px);background-size:140px 170px,230px 210px;background-position:20px 30px,90px 110px;animation:bxdrift 40s linear infinite;-webkit-mask-image:linear-gradient(#000,transparent 85%);mask-image:linear-gradient(#000,transparent 85%)}
body[data-course="chem"] .bx-dots{background-image:radial-gradient(circle,#c3b9ff 1.2px,transparent 1.6px),radial-gradient(circle,#c3b9ff 1px,transparent 1.4px)}
@keyframes bxdrift{to{background-position:20px -140px,90px -100px}}
.bd-hero .wrap{position:relative}
.bx-fan{display:flex;justify-content:center;align-items:flex-end;margin-top:44px;width:100%;padding-bottom:6px}
.bx-pg{position:relative;flex:0 0 auto;width:clamp(96px,15vw,176px);aspect-ratio:3/4;margin:0 -1.2vw;border-radius:8px;background:#fff;box-shadow:0 22px 44px -12px rgba(0,0,0,.7),0 0 0 1px rgba(255,255,255,.25);transform:rotate(calc((var(--i) - 2) * 5deg)) translateY(calc((var(--i) - 2) * (var(--i) - 2) * 7px));transition:transform .35s cubic-bezier(.2,.7,.2,1);overflow:hidden;z-index:calc(5 - (var(--i) - 2) * (var(--i) - 2))}
.bx-pg:hover{transform:rotate(0) translateY(-18px) scale(1.06);z-index:9}
.bx-pg button{display:block;width:100%;height:100%;padding:0;border:0;background:none;cursor:zoom-in}
.bx-pg img{display:block;width:100%;height:100%;object-fit:cover;object-position:top}
.bx-pg .bx-art{width:100%;height:100%}
.bx-pg .bx-art svg{width:100%;height:100%}
.bx-pg .bx-tag{top:auto;bottom:8px;left:8px}
.bx-js .bx-fan.bx-rv .bx-pg{opacity:0;translate:0 50px;scale:.6}
.bx-js .bx-fan.bx-in .bx-pg{opacity:1;translate:0 0;scale:1;transition:opacity .6s calc(var(--i) * .1s),translate .7s calc(var(--i) * .1s) cubic-bezier(.2,.8,.2,1),scale .7s calc(var(--i) * .1s) cubic-bezier(.2,.8,.2,1),transform .35s}

/* sticky step nav */
.bx-steps{position:sticky;top:60px;z-index:15;display:flex;justify-content:center;gap:4px;padding:8px 12px;background:color-mix(in srgb,var(--bg) 90%,transparent);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);overflow-x:auto}
.bx-steps a{display:flex;align-items:center;gap:8px;padding:6px 14px;border-radius:999px;text-decoration:none;font-size:.9rem;font-weight:500;color:var(--muted);white-space:nowrap;transition:background .2s,color .2s}
.bx-steps a b{display:inline-flex;align-items:center;justify-content:center;width:22px;height:22px;border-radius:50%;border:1.5px solid currentColor;font-size:.74rem;font-weight:600}
.bx-steps a:hover{background:var(--panel);color:var(--ink)}
.bx-steps a[aria-current="true"]{background:var(--acc);color:var(--acc-ink)}
.bx-steps a[aria-current="true"] b{border-color:transparent;background:rgba(255,255,255,.25)}

/* reveal */
.bx-js .bx-rv:not(.bx-fan){opacity:0;translate:0 22px;transition:opacity .6s,translate .6s}
.bx-js .bx-rv.bx-in:not(.bx-fan){opacity:1;translate:0 0}

/* unit tiles */
.bd-units{max-width:960px}
.bd-u{padding:0;overflow:hidden;border-top-width:1px;gap:0;align-items:stretch}
.bd-u .bx-ph{display:block;height:112px;overflow:hidden;position:relative;background:#050d0b}
.bd-u .bx-ph img{display:block;width:100%;height:100%;object-fit:cover;transition:transform .5s}
.bd-u:hover .bx-ph img{transform:scale(1.08)}
.bd-u .bx-ph .bx-art{width:100%;height:100%}
.bd-u .bx-ut{display:flex;flex-direction:column;gap:2px;padding:10px 14px 12px}
.bd-u .t{font-size:1rem}
.bd-u[aria-pressed="true"] .n::after{content:"  \2022  open";color:var(--muted);text-transform:none;letter-spacing:0;font-weight:500}
.bd-detail{max-width:960px;padding:0;overflow:hidden}
.bx-banner{position:relative;height:190px;display:flex;align-items:flex-end;background:#050d0b;color:#fff}
.bx-banner img,.bx-banner .bx-art{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.bx-banner::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(0,0,0,.05) 20%,rgba(0,0,0,.78))}
.bx-banner>div:not(.bx-art){position:relative;z-index:1;padding:18px 26px}
.bx-banner>.bx-art{position:absolute}
.bx-banner .n{font-size:.74rem;letter-spacing:.16em;text-transform:uppercase;font-weight:600;color:#7bf5b2}
.bx-banner.chem .n{color:#c3b9ff}
.bx-banner h3{font-size:clamp(1.6rem,3.4vw,2.2rem);margin-top:2px}
.bx-stats4{display:grid;grid-template-columns:repeat(4,1fr);border-bottom:1px solid var(--line)}
.bx-stat{padding:18px 10px;text-align:center;display:flex;flex-direction:column;gap:0}
.bx-stat+.bx-stat{border-left:1px solid var(--line)}
.bx-stat b{font-size:2rem;font-weight:500;color:var(--acc);line-height:1.15;font-variant-numeric:tabular-nums}
.bx-stat span{font-size:.85rem;color:var(--muted)}
.bx-tiles{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;padding:20px 26px 8px}
.bx-tile{display:flex;flex-direction:column;gap:2px;padding:14px;border:1px solid var(--line);border-radius:10px;background:var(--bg);transition:transform .2s,border-color .2s}
.bx-tile:hover{transform:translateY(-3px);border-color:var(--acc)}
.bx-tile svg{width:28px;height:28px;color:var(--acc);margin-bottom:6px}
.bx-tile b{font-weight:500}
.bx-tile span{font-size:.84rem;color:var(--muted)}
.bd-detail h4{padding:14px 26px 0;margin:0}
.bx-try{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:10px;padding:10px 26px 24px}
.bx-try a{display:flex;align-items:center;gap:12px;padding:8px;margin:0}
.bx-try .th{position:relative;flex:0 0 76px;height:52px;border-radius:6px;overflow:hidden;background:#050d0b;display:flex;align-items:center;justify-content:center}
.bx-try .th img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.bx-try .th .bx-art{position:absolute;inset:0;display:block}
.bx-try .th svg{position:relative;width:26px;height:26px;color:#fff;filter:drop-shadow(0 1px 4px rgba(0,0,0,.6))}
.bx-try .th .bx-art svg{width:100%;height:100%;filter:none;color:inherit}
.bx-try .th.alt{background:color-mix(in srgb,var(--acc) 16%,var(--bg))}
.bx-try .th.alt svg{color:var(--acc);filter:none}

/* sample week */
.bx-week{width:100%;max-width:960px;margin-top:26px;display:flex;flex-direction:column;align-items:center;gap:16px}
.bx-days{display:grid;grid-template-columns:repeat(5,1fr);gap:8px;width:100%}
.bx-days.n3{grid-template-columns:repeat(3,1fr)}
.bx-day{display:flex;flex-direction:column;gap:0;padding:10px 8px;border:1px solid var(--line);border-bottom:3px solid var(--line);border-radius:10px;background:var(--bg);color:var(--muted);font:inherit;cursor:pointer;transition:border-color .2s,color .2s,transform .2s}
.bx-day b{font-size:.78rem;letter-spacing:.12em;text-transform:uppercase;font-weight:600}
.bx-day span{font-size:1.05rem;color:var(--ink);font-weight:500}
.bx-day:hover{transform:translateY(-2px)}
.bx-day[aria-selected="true"]{border-color:var(--acc);border-bottom-color:var(--acc);color:var(--acc)}
.bx-stage{width:100%;display:grid;grid-template-columns:1fr 1.5fr;gap:22px;align-items:center;min-height:300px;padding:24px 28px;border:1px solid var(--line);border-radius:14px;background:var(--bg);text-align:left;overflow:hidden}
.bx-sc h3{font-size:clamp(1.8rem,3.4vw,2.4rem);margin:4px 0 8px}
.bx-sc p{color:var(--muted)}
.bx-dn{font-size:.76rem;letter-spacing:.14em;text-transform:uppercase;font-weight:600;color:var(--acc)}
.bx-bar{height:5px;border-radius:3px;background:var(--line);margin-top:18px;overflow:hidden}
.bx-bar i{display:block;height:100%;background:var(--acc);border-radius:3px;transition:width .6s}
.bx-pcs{display:flex;justify-content:center;align-items:center;gap:0;min-height:240px}
.bx-pc{position:relative;flex:0 0 auto;width:clamp(120px,19vw,190px);aspect-ratio:3/4;border-radius:8px;overflow:hidden;background:#fff;box-shadow:0 18px 36px -12px rgba(0,0,0,.55),0 0 0 1px var(--line);margin:0 -10px;transform:rotate(calc(var(--i) * 7deg - 4deg));animation:bxpop .6s calc(var(--i) * .12s) cubic-bezier(.2,.8,.2,1) both}
.bx-pc:nth-child(2){margin-top:22px}
.bx-pc img{display:block;width:100%;height:100%;object-fit:cover;object-position:top}
.bx-pc .bx-art{width:100%;height:100%}
.bx-pc .bx-tag{top:auto;bottom:8px}
.bx-playb{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,.25)}
.bx-playb svg{width:44px;height:44px;color:#fff}
@keyframes bxpop{from{opacity:0;translate:0 40px;scale:.7}to{opacity:1;translate:0 0;scale:1}}
.bx-play{min-width:0}
.bx-week+.bd-note{text-align:center}

/* gallery rail */
.bx-chips{display:flex;gap:8px;flex-wrap:wrap;justify-content:center;margin-top:24px}
.bx-chip{padding:6px 16px;border-radius:999px;border:1px solid var(--line);background:var(--bg);color:var(--muted);font:inherit;font-size:.92rem;font-weight:500;cursor:pointer;transition:background .2s,color .2s}
.bx-chip:hover{border-color:var(--acc);color:var(--ink)}
.bx-chip[aria-pressed="true"]{background:var(--acc);border-color:var(--acc);color:var(--acc-ink)}
.bx-railwrap{position:relative;width:100%;max-width:1120px;margin-top:22px}
.bx-rail{display:flex;gap:16px;overflow-x:auto;scroll-snap-type:x mandatory;padding:6px 4px 14px;text-align:left;scrollbar-width:thin}
.bx-fig{flex:0 0 auto;display:flex;flex-direction:column;width:max-content;max-width:480px;margin:0;scroll-snap-align:start}
.bx-card{display:block;height:300px;max-width:100%;padding:0;border:1px solid var(--line);border-radius:12px;overflow:hidden;background:var(--panel);cursor:zoom-in;transition:transform .25s,box-shadow .25s}
.bx-card:hover{transform:translateY(-4px);box-shadow:0 14px 30px rgba(0,0,0,.2)}
.bx-card img{display:block;height:100%;width:auto;max-width:none}
.bx-fig.art .bx-card{width:480px}
.bx-fig figcaption{width:0;min-width:100%}
.bx-fig.art .bx-card{cursor:pointer;position:relative}
.bx-fig.art .bx-art{width:100%;height:100%}
.bx-fig.art .bx-art svg{width:100%;height:100%}
.bx-fig figcaption{margin-top:8px;font-size:.88rem;color:var(--muted);line-height:1.35}
.bx-fig figcaption b{display:block;color:var(--ink);font-weight:600}
.bx-arr{position:absolute;top:38%;z-index:3;width:42px;height:42px;border-radius:50%;border:1px solid var(--line);background:var(--bg);color:var(--ink);font-size:1.7rem;line-height:1;padding:0 0 4px;cursor:pointer;box-shadow:0 6px 16px rgba(0,0,0,.2)}
.bx-arr:hover{border-color:var(--acc)}
#galPrev{left:-10px}#galNext{right:-10px}

/* simulator picker */
.bx-simpick{display:flex;gap:8px;overflow-x:auto;width:100%;max-width:960px;margin-top:24px;padding:4px 2px 10px;scroll-snap-type:x proximity}
.bx-sp{flex:0 0 auto;width:118px;padding:0;border:2px solid var(--line);border-radius:10px;overflow:hidden;background:var(--bg);color:var(--ink);font:inherit;cursor:pointer;text-align:left;scroll-snap-align:start;transition:border-color .2s,transform .2s}
.bx-sp:hover{transform:translateY(-2px)}
.bx-sp[aria-pressed="true"]{border-color:var(--acc);box-shadow:0 0 0 1px var(--acc)}
.bx-sp .bx-ph{display:block;height:64px;background:#050d0b;overflow:hidden}
.bx-sp .bx-ph img{display:block;width:100%;height:100%;object-fit:cover}
.bx-sp .bx-ph .bx-art{width:100%;height:100%}
.bx-sp b{display:block;padding:6px 8px;font-size:.76rem;font-weight:500;line-height:1.25;min-height:2.9em}

/* folder */
.bx-folder{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;width:100%;max-width:820px;margin-top:28px}
.bx-fo{display:flex;flex-direction:column;align-items:center;gap:2px;padding:20px 12px;border:1px solid var(--line);border-radius:12px;background:var(--panel);color:var(--ink);font:inherit;cursor:pointer;transition:transform .2s,border-color .2s}
.bx-fo svg{width:34px;height:34px;color:var(--acc);margin-bottom:6px;transition:transform .3s}
.bx-fo:hover{transform:translateY(-3px)}
.bx-fo:hover svg{transform:scale(1.15)}
.bx-fo b{font-weight:500}
.bx-fo span{font-size:.85rem;color:var(--muted)}
.bx-fo[aria-pressed="true"]{border-color:var(--acc);box-shadow:0 0 0 1px var(--acc);background:var(--bg)}
.bx-folder-note{max-width:60ch;min-height:3.2em;margin-top:18px;color:var(--muted);font-size:1.02rem}

@media (max-width:900px){.bx-stage{grid-template-columns:1fr;text-align:center}.bx-sc{text-align:center}.bx-tiles{grid-template-columns:repeat(2,1fr)}.bx-folder{grid-template-columns:repeat(2,1fr)}}
@media (max-width:700px){.bx-steps{justify-content:flex-start}.bx-steps a span{display:inline}.bx-stats4{grid-template-columns:repeat(2,1fr)}.bx-stat:nth-child(3){border-left:0}.bx-stat:nth-child(n+3){border-top:1px solid var(--line)}.bx-days{grid-template-columns:repeat(5,minmax(64px,1fr));overflow-x:auto}.bx-days.n3{grid-template-columns:repeat(3,1fr)}.bx-banner{height:150px}.bx-tiles,.bx-try{padding-inline:16px}.bd-detail h4{padding-inline:16px}.bx-fan .bx-pg:nth-child(1),.bx-fan .bx-pg:nth-child(5){display:none}#galPrev,#galNext{display:none}}
@media (max-width:560px){.bx-steps{top:73px}.bd-units{grid-template-columns:repeat(2,1fr)}.bd-u .bx-ph{height:84px}.bx-stage{padding:18px 14px}}
@media (prefers-reduced-motion:reduce){.bx-dots,.bx-pc{animation:none}.bx-js .bx-rv,.bx-js .bx-fan.bx-rv .bx-pg{opacity:1!important;translate:none!important;scale:none!important;transition:none}.bx-ca *{animation:none!important}}