:root{--bg:#0d1117;--panel:#161b22;--fg:#e6edf3;--muted:#8b949e;--accent:#3b82f6;--border:#232a33}*{box-sizing:border-box}body,html{margin:0;padding:0;height:100%;background:var(--bg);color:var(--fg);font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;scrollbar-width:none;-ms-overflow-style:none}body::-webkit-scrollbar,html::-webkit-scrollbar{width:0;height:0;display:none}.no-scrollbar{overflow:auto;scrollbar-width:none;-ms-overflow-style:none}.no-scrollbar::-webkit-scrollbar{width:0;height:0;display:none}a{color:var(--accent);text-decoration:none}.shell{min-height:100%;display:flex;flex-direction:column}.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:14px 20px;border-bottom:1px solid var(--border);background:var(--panel)}.topbar__brand{font-weight:700;letter-spacing:.5px}.topbar__nav{display:flex;gap:16px;align-items:center}.lang-switch{display:inline-flex;align-items:center;gap:8px;color:var(--muted);font-size:13px}.lang-switch select{background:var(--bg);color:var(--fg);border:1px solid var(--border);border-radius:6px;padding:4px 8px;font-size:13px}.content{flex:1 1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;padding:40px 20px;text-align:center}.content h1{margin:0;font-size:40px}.content p{margin:0;color:var(--muted)}