:root{--ink:#102b46;--muted:#526778;--paper:#f4f7fa;--white:#fff;--line:#d7e2eb;--teal:#007b78;--blue:#164fce;--pale:#e9f3f4;--orange:#a14500;--danger:#a12435;--radius:18px;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--ink);background:var(--paper);font-size:16px}*{box-sizing:border-box}body{margin:0}button,input{font:inherit}button,a,input{touch-action:manipulation}button{cursor:pointer}button:disabled{opacity:.6;cursor:default}button:focus-visible,a:focus-visible,input:focus-visible,[role=button]:focus-visible{outline:3px solid #d28919;outline-offset:4px}a{color:var(--blue)}.top{background:var(--ink);color:white;padding:18px max(24px,calc((100vw - 1200px)/2));display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap}.brand{color:white;text-decoration:none;display:flex;align-items:center;gap:10px;font-weight:750;font-size:1.3rem}.brand-sub{font-size:.85rem;font-weight:400;opacity:.75;border-left:1px solid #688093;padding-left:12px}.mark{color:#77e2cf;font-size:1.8rem}nav{display:flex;gap:10px;align-items:center;flex-wrap:wrap}nav button{background:transparent;color:white;border:1px solid #577086;padding:8px 12px;border-radius:8px}main{max-width:1200px;padding:36px 24px 60px;margin:auto;min-height:80vh}h1{font-size:clamp(1.8rem,4vw,2.6rem);letter-spacing:-.045em;line-height:1.15;margin:8px 0 14px}h2{font-size:1.35rem;letter-spacing:-.02em;margin:0 0 12px}h3{margin:0 0 10px;font-size:1.06rem}p{line-height:1.6;margin:8px 0 16px}.eyebrow{text-transform:uppercase;letter-spacing:.12em;font-size:.76rem;font-weight:750;color:var(--teal)}.muted{color:var(--muted)}.intro{display:flex;justify-content:space-between;align-items:end;gap:24px;margin-bottom:26px}.intro p{max-width:640px}.badge{font-size:.8rem;background:var(--pale);color:#005c5a;border-radius:20px;padding:6px 12px;display:inline-block}.panel{background:var(--white);border:1px solid var(--line);border-radius:var(--radius);padding:26px}.login{max-width:980px;display:grid;grid-template-columns:1.1fr 1fr;margin:36px auto;overflow:hidden;background:white;border:1px solid var(--line);border-radius:22px}.login-copy{padding:48px;background:var(--ink);color:white;position:relative;overflow:hidden}.login-copy .eyebrow{color:#77e2cf}.login-copy p{color:#c7d8e7}.login form{padding:40px}.login-art{width:100%;max-height:190px;color:#77e2cf;margin-top:20px}label{display:block;font-weight:600;margin-bottom:16px}input:not([type=checkbox]){width:100%;border:1px solid #9cafbe;border-radius:9px;background:white;color:var(--ink);padding:12px;margin-top:7px;min-height:46px}input[type=checkbox]{width:19px;height:19px;accent-color:var(--teal)}button.primary{background:var(--teal);color:white;border:1px solid var(--teal);border-radius:9px;padding:12px 20px;font-weight:650}.secondary{background:white;color:var(--ink);border:1px solid #a7b9c7;border-radius:9px;padding:11px 18px}.text-button{border:0;background:none;color:var(--blue);padding:10px 0}.full{width:100%}.error{color:var(--danger);line-height:1.5}.status{background:var(--pale);padding:14px 18px;border-radius:9px;margin:12px 0;line-height:1.55}.stats{display:flex;gap:24px;margin:20px 0 30px;flex-wrap:wrap}.stat{min-width:120px;border-left:3px solid var(--teal);padding-left:14px}.stat strong{display:block;font-size:1.65rem}.stat span{font-size:.85rem;color:var(--muted)}.section-title{display:flex;justify-content:space-between;align-items:center;margin:28px 0 16px}.topic-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.topic{background:white;border:1px solid var(--line);border-radius:15px;padding:23px;display:flex;flex-direction:column;gap:8px}.topic .number{font-size:.8rem;color:var(--teal);font-weight:700}.topic p{color:var(--muted);font-size:.95rem;flex:1}.topic button{text-align:left;display:flex;justify-content:space-between}.progress{height:6px;background:#e3ebf1;border-radius:5px;overflow:hidden;margin:8px 0}.progress span{display:block;height:100%;background:var(--teal)}.small{font-size:.82rem}.workspace{display:grid;grid-template-columns:minmax(0,1fr) 290px;gap:24px;align-items:start}.playhead{display:flex;justify-content:space-between;align-items:center;gap:15px;margin-bottom:20px}.playhead .badge{white-space:nowrap}.diagram{background:#f5f9fc;border:1px solid var(--line);border-radius:12px;margin:20px 0;overflow:hidden}.diagram svg{display:block;width:100%;height:auto;max-height:300px;color:var(--ink)}svg text{font-family:inherit;font-size:16px;fill:currentColor}svg .line{stroke:currentColor;stroke-width:2.5;fill:none}svg .dash{stroke-dasharray:6 5}svg .accent{stroke:var(--teal);fill:none;stroke-width:3}svg .point{fill:var(--teal)}svg .hit{cursor:pointer}svg .hit:hover circle,svg .hit.selected circle{fill:#164fce}svg .hit.selected text{font-weight:800}svg .hit circle.target{fill:transparent;stroke:none}svg .candidate{fill:white;stroke:#9cafbe;stroke-width:1.5}svg .hit.selected .candidate{stroke:var(--teal);stroke-width:4;fill:#e9f3f4}.choices{display:grid;gap:10px;margin:20px 0}.choice{text-align:left;background:white;border:1px solid #a7b9c7;border-radius:10px;padding:15px;min-height:50px;color:var(--ink)}.choice.selected{border:2px solid var(--teal);padding:14px;background:var(--pale)}.actions{display:flex;align-items:center;justify-content:space-between;gap:15px;flex-wrap:wrap;margin-top:22px}.tool{background:#e9f3f4;border:1px solid #c3dddd;border-radius:15px;padding:23px}.tool h2{font-size:1.1rem}.tool p{font-size:.95rem}.feedback{padding:20px;border-radius:12px;background:#e9f3f4;border-left:4px solid var(--teal);margin-top:20px}.feedback.wrong{background:#fff4e9;border-left-color:var(--orange)}.feedback h3{margin:0 0 8px}.admin-layout{display:grid;grid-template-columns:1fr 1fr;gap:24px;align-items:start}.student{display:flex;justify-content:space-between;gap:12px;align-items:center;padding:16px 0;border-bottom:1px solid var(--line)}.student strong{display:block}.student small{color:var(--muted)}.check{display:flex;align-items:center;gap:10px;font-weight:400;margin:12px 0}.assignments{border:1px solid var(--line);border-radius:10px;padding:15px;margin:16px 0}.assignments legend{font-weight:650}.report{overflow:auto;margin-top:20px}table{width:100%;border-collapse:collapse;font-size:.86rem}th,td{text-align:left;padding:10px 7px;border-bottom:1px solid var(--line)}footer{max-width:1200px;margin:auto;padding:22px 24px;color:var(--muted);border-top:1px solid var(--line);font-size:.85rem;display:flex;justify-content:space-between;gap:10px}#notice:not(:empty){padding:10px 24px;text-align:center;background:#fff0c7;color:#5a3a00}.loading{padding:50px;text-align:center}.empty{padding:40px;text-align:center}.hidden{display:none!important}@media(max-width:950px){.topic-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.workspace{grid-template-columns:1fr}.tool{order:2}.admin-layout{grid-template-columns:1fr}}@media(max-width:620px){main{padding:24px 16px}.top{padding:14px 16px}.brand-sub{display:none}.login{display:block;margin:0}.login-copy{padding:28px}.login-art{display:none}.login form{padding:26px}.topic-grid{grid-template-columns:1fr}.intro{display:block}.panel{padding:20px}.stats{gap:18px}.stat{min-width:90px}.playhead{align-items:start}.playhead .badge{white-space:normal}.student{flex-wrap:wrap}footer{flex-wrap:wrap}}
svg circle.target{fill:transparent;stroke:none}