:root{color-scheme:light;font-family:Inter,"Segoe UI","Microsoft YaHei",sans-serif;color:#1c2542;background:#f7f9ff;font-synthesis:none;--muted:#707c96;--line:#e0e6f3;--blue:#3057f6}*{box-sizing:border-box}[hidden]{display:none!important}body{margin:0;line-height:1.6;background:radial-gradient(ellipse at 50% 0,#eef2ff,transparent 65%)}a{color:inherit}.topbar{display:flex;justify-content:space-between;align-items:center;padding:22px max(24px,calc((100vw - 1240px)/2));border-bottom:1px solid var(--line);background:#ffffffb8}.brand{display:flex;align-items:center;gap:10px;font-size:17px;font-weight:800;text-decoration:none}.brand-mark{display:grid;place-items:center;width:32px;height:32px;background:var(--blue);color:white;border-radius:10px}.status-pill{display:flex;align-items:center;gap:8px;font-size:12px;color:var(--muted)}.status-dot{height:7px;width:7px;background:#24a57e;border-radius:50%}main{max-width:1280px;margin:auto;padding:72px 28px 48px}.intro{text-align:center}.eyebrow{font-size:11px;letter-spacing:3px;color:var(--blue);font-weight:700}h1{font-size:clamp(32px,4.3vw,60px);letter-spacing:-2px;line-height:1.25;margin:16px 0}p{margin:0}.lede{color:var(--muted);font-size:16px}.intro-meta{display:flex;justify-content:center;align-items:center;gap:12px;margin-top:24px;color:var(--muted);font-size:12px}.meta-divider{width:1px;height:14px;background:var(--line)}#system-hint{color:var(--blue)}.release-section{margin-top:54px}.section-heading{display:flex;justify-content:space-between;align-items:end;margin-bottom:22px}.section-label{font-size:11px;letter-spacing:2px;color:var(--blue)}h2{font-size:21px;margin:2px 0}.section-note{font-size:12px;color:var(--muted)}.platform-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}.platform-card{position:relative;background:white;border:1px solid var(--line);border-radius:24px;min-height:355px;padding:34px 26px 26px;display:flex;align-items:center;flex-direction:column;text-align:center;box-shadow:0 10px 35px #233e8610}.platform-card.recommended{border:1.5px solid #7890ff;box-shadow:0 12px 40px #315bff1a}.recommended-badge{position:absolute;top:-14px;border-radius:20px;padding:4px 14px;background:var(--blue);color:white;font-size:11px;font-weight:700}.platform-icon{width:44px;height:44px;color:var(--blue);margin:8px auto 12px}.platform-icon svg{width:100%;height:100%;fill:currentColor}.platform-card h3{font-size:28px;margin:0 0 4px}.version{color:var(--blue);font-size:17px}.download-options{width:100%;display:grid;gap:9px;margin:25px 0 20px}.download-button{display:inline-flex;justify-content:center;align-items:center;min-height:46px;gap:8px;border-radius:30px;background:#edf1ff;color:#2d50dc;padding:10px 20px;font-size:14px;font-weight:650;text-decoration:none;transition:background .15s}.download-button:hover{background:#dde5ff}.download-button.primary{background:var(--blue);color:white}.download-button.primary:hover{background:#2045d4}.download-button:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #91a6ff;outline-offset:4px}.platform-meta{font-size:12px;color:var(--muted);margin-top:auto;line-height:1.8}.unavailable{display:block;border-radius:30px;padding:11px;background:#f4f6fa;color:#8b94a9;font-size:14px}.release-list{display:grid;gap:10px}.release-card{display:flex;justify-content:space-between;align-items:center;gap:18px;padding:20px 24px;border:1px solid var(--line);border-radius:16px;background:white}.release-card strong{font-size:15px}.history-section{margin-top:30px}.history-section summary{cursor:pointer;color:var(--blue);padding:14px;text-align:center}.history-section[open] summary{margin-bottom:12px}.empty-row,.loading-row{padding:22px;color:var(--muted);text-align:center;font-size:14px}.error-message{padding:18px;border-radius:12px;background:#fff0e9;color:#a13f21;margin-top:24px;font-size:14px}button{border:1px solid currentColor;border-radius:8px;background:transparent;color:inherit;cursor:pointer;padding:6px 10px;margin-left:10px}.footer{max-width:1224px;margin:auto;border-top:1px solid var(--line);display:flex;justify-content:space-between;padding:22px 0 30px;color:var(--muted);font-size:12px}@media(max-width:850px){main{padding-top:42px}.platform-grid{gap:14px}.platform-card{padding:30px 14px 22px}.download-button{font-size:12px;padding:10px}.footer{margin:0 24px}}@media(max-width:650px){.platform-grid{grid-template-columns:1fr;gap:26px}.platform-card{min-height:310px}.section-note{display:none}.intro-meta{flex-direction:column;gap:6px}.meta-divider{display:none}.release-card{align-items:flex-start;flex-direction:column}.release-card .download-button{width:100%}.topbar{padding:18px 22px}.status-pill{display:none}h1{letter-spacing:-1px}.footer{gap:10px;flex-wrap:wrap}}

[hidden] { display: none !important; }
.download-tabs { display: flex; gap: 8px; padding: 6px; margin: 28px auto 32px; width: fit-content; max-width: 100%; border: 1px solid #e2e8f0; border-radius: 16px; background: #f3f6fc; }
.download-tabs button { border: 0; border-radius: 11px; padding: 12px 24px; background: transparent; color: #64748b; font: inherit; font-weight: 600; cursor: pointer; }
.download-tabs button[aria-selected="true"] { background: #fff; color: #315cf4; box-shadow: 0 2px 8px #162b5212; }
.download-tabs button:focus-visible { outline: 2px solid #315cf4; outline-offset: 2px; }
@media(max-width:480px) { .download-tabs button { padding: 12px 16px; } }

.chip-help{font-size:13px;color:var(--muted);margin:0 0 24px;line-height:1.8}
.engine-platform h3{margin:20px 0 8px}.engine-architecture h4{font-size:14px;color:var(--muted);margin:12px 0}
.engine-architecture{display:grid;gap:10px;margin-bottom:20px}
[data-tip]{position:relative}
[data-tip]::after{content:attr(data-tip);position:absolute;bottom:calc(100% + 8px);left:50%;transform:translateX(-50%);width:max-content;max-width:min(260px,75vw);padding:7px 10px;border-radius:8px;background:#17213b;color:white;font-size:12px;line-height:1.5;font-weight:400;pointer-events:none;opacity:0;visibility:hidden;z-index:10;transition:opacity .15s}
[data-tip]:hover::after,[data-tip]:focus-visible::after{opacity:1;visibility:visible}
@media(prefers-reduced-motion:reduce){[data-tip]::after{transition:none}}