:root{--bg:#f4f6f8;--card:#fff;--ink:#1f2937;--muted:#5b6877;--line:#d8dee6;--blue:#1c7e9b;--red:#ad3452;--pill:#eef3f7;--shadow:0 10px 30px rgba(31,41,55,.08)}
*{box-sizing:border-box}body{margin:0;font-family:Inter,Segoe UI,Arial,sans-serif;background:linear-gradient(180deg,#f7f8fb 0%,#eef2f6 100%);color:var(--ink)}
.hero{display:flex;gap:18px;align-items:flex-start;padding:36px 42px 20px}.logo{display:grid;grid-template-columns:repeat(2,14px);grid-template-rows:repeat(2,14px);gap:6px;margin-top:8px}.logo i{display:block;width:14px;height:14px;border-radius:4px}.logo i:nth-child(1){background:#1c7e9b}.logo i:nth-child(2){background:#ad3452}.logo i:nth-child(3){background:#d59e19}.logo i:nth-child(4){background:#2d8a5f}.eyebrow{margin:0 0 8px;font-size:.8rem;letter-spacing:.18em;text-transform:uppercase;color:#687588;font-weight:700}.eyebrow.dark{color:#4b5563}.hero h1{margin:0 0 10px;font-size:2.25rem;line-height:1.1}.hero p{max-width:980px;margin:0;color:var(--muted);line-height:1.55}
main{padding:0 28px 24px}.selector,.workspace{background:rgba(255,255,255,.8);border:1px solid rgba(216,222,230,.95);backdrop-filter:blur(10px);border-radius:24px;box-shadow:var(--shadow);padding:22px 22px 24px;margin-bottom:18px}.heading-row{display:flex;justify-content:space-between;gap:12px;align-items:flex-start}.heading-row h2{margin:4px 0 10px;font-size:1.5rem}.status{background:#e8f5ec;color:#166534;padding:10px 14px;border-radius:999px;font-weight:700}.help{margin:0 0 18px;color:var(--muted);line-height:1.5}
.article-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.article-card{border:1px solid var(--line);background:var(--card);border-radius:18px;padding:16px 16px 14px;display:block;position:relative;min-height:220px;box-shadow:0 8px 22px rgba(15,23,42,.04)}.article-card.selected{border-color:#9ebdd0;background:linear-gradient(180deg,#ffffff 0%,#f6fbfe 100%)}.article-card input{position:absolute;top:16px;right:16px;width:18px;height:18px}.article-card .num{font-size:.92rem;font-weight:800;color:#334155;margin-bottom:6px;padding-right:28px}.article-card h3{margin:0 0 8px;font-size:1.08rem;line-height:1.25}.article-card p{margin:0 0 12px;color:var(--muted);font-size:.95rem;line-height:1.45}.tag{display:inline-block;background:var(--pill);border:1px solid #d9e2ea;border-radius:999px;padding:7px 11px;font-size:.84rem;color:#415364}
.tabs{display:flex;flex-wrap:wrap;gap:10px;margin:4px 0 18px}.tab{border:1px solid #cfd8e3;background:#fff;border-radius:999px;padding:10px 16px;font-weight:700;color:#334155;cursor:pointer}.tab.active{background:#0f172a;color:#fff;border-color:#0f172a}.layout{display:grid;grid-template-columns:1.12fr .88fr;gap:18px;align-items:start}.diagram-card,.details{background:#fff;border:1px solid var(--line);border-radius:22px;padding:18px;box-shadow:0 8px 24px rgba(15,23,42,.05)}#venn{width:100%;height:auto;display:block}.set-shape{stroke-width:3;cursor:pointer;transition:opacity .2s ease,stroke-width .2s ease}.set-shape.active{stroke-width:5}.set-label{font-size:19px;font-weight:800;fill:#1f2937}.center-pill{fill:#fff;stroke:#cbd5e1;stroke-width:2;cursor:pointer}.center-label{font-size:16px;font-weight:800;fill:#111827}.center-label-small{font-size:13px;font-weight:600;fill:#4b5563}.note{margin:8px 0 12px;color:var(--muted);font-size:.95rem}.chips{display:flex;flex-wrap:wrap;gap:10px}.chip{border:1px solid #d7dee7;background:#fff;border-radius:999px;padding:9px 14px;font-weight:700;color:#334155;cursor:pointer}.chip.active{background:#0f172a;color:#fff;border-color:#0f172a}.details .kicker{font-size:.8rem;letter-spacing:.12em;text-transform:uppercase;color:#64748b;font-weight:700;margin-bottom:10px}.details h3{margin:0 0 14px;font-size:1.35rem;line-height:1.25}.block{padding:14px 0;border-top:1px solid #e6ebf1}.block:first-of-type{padding-top:0;border-top:none}.block h4{margin:0 0 8px;font-size:1rem}.block p,.block li{color:#445164;line-height:1.55}.block ul{margin:0;padding-left:18px}.pdfs{display:flex;flex-wrap:wrap;gap:10px}.pdfs a{display:inline-flex;flex-direction:column;gap:2px;text-decoration:none;color:#0f172a;border:1px solid #d7dee7;padding:10px 12px;border-radius:14px;background:#fbfdff;font-weight:700}.pdfs a span{font-size:.82rem;color:#64748b;font-weight:600}
.ellipse-copy-object{overflow:visible}.ellipse-copy{width:100%;height:100%;padding:6px 8px;border-radius:14px;overflow:hidden;color:#14202b;background:rgba(255,255,255,.34);backdrop-filter:blur(2px)}.ellipse-copy-heading{font-weight:800;font-size:10px;letter-spacing:.05em;text-transform:uppercase;margin-bottom:4px}.ellipse-copy ul{margin:0;padding-left:13px}.ellipse-copy li{margin:0 0 2px 0;line-height:1.12}
footer{padding:0 28px 30px;color:#64748b;display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap}
@media (max-width:980px){.layout{grid-template-columns:1fr}.hero{padding:28px 24px 16px;flex-direction:column}.article-grid{grid-template-columns:1fr}main{padding:0 16px 20px}}