.hn-lab{--hn-ink:#17313a;--hn-green:#267e68;--hn-blue:#377eb8;--hn-pale:#eef7f3;max-width:1220px;margin:0 auto;padding:clamp(18px,3vw,36px);color:var(--hn-ink);font-family:Helvetica,Arial,sans-serif}.hn-hero{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(320px,.75fr);gap:24px;align-items:end;padding:clamp(22px,4vw,44px);border-radius:28px;background:linear-gradient(135deg,#133845 0%,#245b5b 55%,#4e8f73 100%);color:#fff;box-shadow:0 20px 50px rgba(22,54,61,.18)}.hn-hero>div>span,.hn-kicker{font-size:13px;font-weight:800;letter-spacing:.12em;text-transform:uppercase}.hn-hero h2{margin:8px 0 10px;font-size:clamp(34px,5vw,64px);line-height:.98;letter-spacing:-.055em}.hn-hero p{max-width:680px;margin:0;color:#e3f1ee;font-size:17px;line-height:1.55}.hn-family{display:grid;grid-template-columns:1fr 1fr;gap:10px}.hn-family button{min-height:88px;padding:14px;border:1px solid rgba(255,255,255,.34);border-radius:18px;background:rgba(255,255,255,.09);color:#fff;text-align:left;cursor:pointer;transition:transform .2s ease,background .2s ease,border-color .2s ease}.hn-family button:hover{transform:translateY(-2px);background:rgba(255,255,255,.16)}.hn-family button.active{border-color:#fff;background:#fff;color:#17313a;box-shadow:0 9px 24px rgba(0,0,0,.16)}.hn-family strong,.hn-family small{display:block}.hn-family strong{font-size:18px}.hn-family small{margin-top:5px;font-size:13px;opacity:.78}.hn-controls{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin:22px 0}.hn-controls fieldset{min-width:0;margin:0;padding:18px;border:1px solid #cedfda;border-radius:20px;background:#fff}.hn-controls legend{padding:0 8px;color:#45636a;font-size:14px;font-weight:800}.hn-carbon-buttons,.hn-position-buttons{display:flex;gap:8px;flex-wrap:wrap}.hn-carbon-buttons button,.hn-position-buttons button{min-width:60px;min-height:50px;padding:8px 12px;border:1px solid #cbdcd7;border-radius:13px;background:#f8fbfa;color:#36545d;cursor:pointer;font:700 15px Helvetica,Arial,sans-serif;transition:transform .16s ease,background .16s ease,color .16s ease}.hn-carbon-buttons button span{display:block;font-size:11px;font-weight:600}.hn-carbon-buttons button:hover,.hn-position-buttons button:hover{transform:translateY(-2px);border-color:#4b9983}.hn-carbon-buttons button.active,.hn-position-buttons button.active{background:var(--hn-green);border-color:var(--hn-green);color:#fff;box-shadow:0 7px 16px rgba(38,126,104,.22)}.hn-workspace{display:grid;grid-template-columns:minmax(0,1.55fr) minmax(290px,.75fr);gap:18px}.hn-visual,.hn-rules,.hn-challenge{border:1px solid #d2e1dc;border-radius:24px;background:#fff;box-shadow:0 10px 30px rgba(30,67,64,.07)}.hn-visual{overflow:hidden}.hn-visual-head{display:flex;justify-content:space-between;gap:12px;padding:16px 20px;background:#edf6f2;color:#365b5d;font-size:14px;font-weight:800}.hn-visual-head span:last-child{color:var(--hn-green);font-size:20px}.hn-canvas{display:flex;min-height:280px;align-items:center;justify-content:center;overflow-x:auto;padding:16px}.hn-canvas svg{width:100%;min-width:520px;max-height:250px}.hn-atom circle{fill:#f6fbf9;stroke:#317e70;stroke-width:4}.hn-atom>text:not(.hn-h-label){fill:#17313a;font-size:28px;font-weight:800;text-anchor:middle}.hn-h-label{fill:#587078;font-size:14px;font-weight:700;text-anchor:middle}.hn-bond line{stroke:#397a73;stroke-width:7;stroke-linecap:round}.hn-bond.double line{stroke:#c56341}.hn-locant{fill:#7b8e93;font-size:13px;font-weight:800;text-anchor:middle}.hn-result{padding:0 22px 22px;text-align:center}.hn-result small{color:#668087;font-size:12px;font-weight:800;letter-spacing:.1em;text-transform:uppercase}.hn-result h3{margin:4px 0;color:#17313a;font-size:clamp(30px,4vw,48px);letter-spacing:-.04em}.hn-result p{margin:0;color:#506a71;font-size:16px}.hn-rules{padding:24px}.hn-rules .hn-kicker{color:var(--hn-green)}.hn-rules ol{display:grid;gap:12px;margin:16px 0;padding:0;list-style:none}.hn-rules li{display:flex;gap:12px;align-items:flex-start;padding:14px;border-radius:16px;background:#f3f8f6}.hn-rules li>b{display:grid;width:30px;height:30px;flex:0 0 30px;place-items:center;border-radius:50%;background:var(--hn-green);color:#fff}.hn-rules strong,.hn-rules small{display:block}.hn-rules strong{font-size:15px}.hn-rules small{margin-top:4px;color:#587078;font-size:13px;line-height:1.4}.hn-rule-note{padding:14px;border-left:4px solid #e49b52;border-radius:8px;background:#fff5e8;color:#5d4d3d;font-size:14px;line-height:1.45}.hn-challenge{display:grid;grid-template-columns:minmax(230px,.65fr) minmax(0,1.35fr);gap:24px;align-items:center;margin-top:18px;padding:24px}.hn-challenge>div>span{color:var(--hn-blue);font-size:12px;font-weight:800;letter-spacing:.1em;text-transform:uppercase}.hn-challenge h3{margin:5px 0;font-size:24px}.hn-challenge p{margin:0;color:#60757b;font-size:14px;line-height:1.45}.hn-challenge label{display:block;margin-bottom:7px;font-size:13px;font-weight:800}.hn-challenge form>div{display:flex;gap:8px}.hn-challenge input{min-width:0;flex:1;padding:13px 14px;border:1px solid #bfcfcb;border-radius:12px;font:16px Helvetica,Arial,sans-serif}.hn-challenge button{padding:12px 16px;border:1px solid #25745f;border-radius:12px;background:#fff;color:#25745f;font-weight:800;cursor:pointer}.hn-challenge button[type=submit]{background:#25745f;color:#fff}.hn-challenge output{display:block;min-height:22px;margin-top:9px;font-size:14px;font-weight:700}.hn-challenge output.correct{color:#18764c}.hn-challenge output.incorrect{color:#a94834}
@media(max-width:860px){.hn-hero,.hn-workspace,.hn-challenge{grid-template-columns:1fr}.hn-controls{grid-template-columns:1fr}.hn-family{max-width:560px}.hn-canvas{min-height:230px}.hn-rules{padding:20px}}
@media(max-width:560px){.hn-lab{padding:12px}.hn-hero{padding:22px;border-radius:22px}.hn-hero h2{font-size:38px}.hn-hero p{font-size:15px}.hn-family{grid-template-columns:1fr 1fr}.hn-family button{min-height:78px}.hn-controls{margin:14px 0}.hn-controls fieldset{padding:14px}.hn-workspace{gap:14px}.hn-canvas{justify-content:flex-start;padding:10px}.hn-canvas svg{min-width:470px}.hn-challenge{padding:18px}.hn-challenge form>div{display:grid;grid-template-columns:1fr 1fr}.hn-challenge input{grid-column:1/-1}.hn-visual-head{align-items:center}.hn-visual-head span:last-child{font-size:17px}}