:root{--bg: #ffffff;--bg-card: #ffffff;--bg-sticky: #ffffff;--bg-input: #f7f7f9;--bg-chip: #f3f4f8;--text: #14151a;--text-muted: #6b7280;--text-faint: #9ca3af;--border: #e5e7eb;--border-strong: #d1d5db;--accent: #4f46e5;--accent-hover: #4338ca;--accent-text: #4338ca;--accent-soft: #eef0fd;--accent-ring: rgba(79, 70, 229, .18);--success: #16a34a;--success-soft: #ecfdf3;--error: #dc2626;--error-soft: #fef2f2;--shadow-card: 0 20px 40px -20px rgba(20, 21, 26, .18), 0 2px 8px -2px rgba(20, 21, 26, .06);--shadow-sticky: 0 -8px 16px -12px rgba(20, 21, 26, .12);--diagram-line: #4b4f5b;--diagram-fill: rgba(79, 70, 229, .14);--diagram-fill-strong: rgba(79, 70, 229, .35);--radius-card: 16px;--radius-input: 10px;--font-ui: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif}@media(prefers-color-scheme:dark){:root{--bg: #0f1115;--bg-card: #1a1d23;--bg-sticky: #1a1d23;--bg-input: #22252c;--bg-chip: #22252c;--text: #f2f3f5;--text-muted: #9ca3af;--text-faint: #6b7280;--border: #2a2d35;--border-strong: #383c46;--accent: #6366f1;--accent-hover: #7c7ff5;--accent-text: #a5b4fc;--accent-soft: #232244;--accent-ring: rgba(129, 140, 248, .28);--success: #4ade80;--success-soft: #10231a;--error: #f87171;--error-soft: #2a1414;--shadow-card: none;--shadow-sticky: 0 -8px 16px -12px rgba(0, 0, 0, .5);--diagram-line: #c6c9d2;--diagram-fill: rgba(129, 140, 248, .16);--diagram-fill-strong: rgba(129, 140, 248, .4)}}:root[data-theme=light]{--bg: #ffffff;--bg-card: #ffffff;--bg-sticky: #ffffff;--bg-input: #f7f7f9;--bg-chip: #f3f4f8;--text: #14151a;--text-muted: #6b7280;--text-faint: #9ca3af;--border: #e5e7eb;--border-strong: #d1d5db;--accent: #4f46e5;--accent-hover: #4338ca;--accent-text: #4338ca;--accent-soft: #eef0fd;--accent-ring: rgba(79, 70, 229, .18);--success: #16a34a;--success-soft: #ecfdf3;--error: #dc2626;--error-soft: #fef2f2;--shadow-card: 0 20px 40px -20px rgba(20, 21, 26, .18), 0 2px 8px -2px rgba(20, 21, 26, .06);--shadow-sticky: 0 -8px 16px -12px rgba(20, 21, 26, .12);--diagram-line: #4b4f5b;--diagram-fill: rgba(79, 70, 229, .14);--diagram-fill-strong: rgba(79, 70, 229, .35)}:root[data-theme=dark]{--bg: #0f1115;--bg-card: #1a1d23;--bg-sticky: #1a1d23;--bg-input: #22252c;--bg-chip: #22252c;--text: #f2f3f5;--text-muted: #9ca3af;--text-faint: #6b7280;--border: #2a2d35;--border-strong: #383c46;--accent: #6366f1;--accent-hover: #7c7ff5;--accent-text: #a5b4fc;--accent-soft: #232244;--accent-ring: rgba(129, 140, 248, .28);--success: #4ade80;--success-soft: #10231a;--error: #f87171;--error-soft: #2a1414;--shadow-card: none;--shadow-sticky: 0 -8px 16px -12px rgba(0, 0, 0, .5);--diagram-line: #c6c9d2;--diagram-fill: rgba(129, 140, 248, .16);--diagram-fill-strong: rgba(129, 140, 248, .4)}*{box-sizing:border-box}[hidden]{display:none!important}html{-webkit-text-size-adjust:100%}body{margin:0;font-family:var(--font-ui);background:var(--bg);color:var(--text);overflow-x:hidden;-webkit-font-smoothing:antialiased}img,svg{max-width:100%}a{color:var(--accent-text)}h1,h2,h3{line-height:1.2;margin:0}p{margin:0}button{font-family:inherit}.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0;padding:0;margin:-1px}main{display:block}.wrap{max-width:1100px;margin:0 auto;padding:0 16px}.site-header{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:4px 16px;border-bottom:1px solid var(--border);background:var(--bg);position:relative;z-index:20}.logo{font-size:18px;font-weight:800;letter-spacing:-.02em;color:var(--text);text-decoration:none;white-space:nowrap}.logo span{color:var(--accent-text)}.nav-links{display:none;list-style:none;margin:0;padding:0;gap:20px;font-size:14px}.nav-links a{color:var(--text-muted);text-decoration:none;font-weight:500}.nav-links a:hover{color:var(--accent-text)}.theme-toggle{width:40px;height:40px;min-width:44px;min-height:44px;display:flex;align-items:center;justify-content:center;border-radius:10px;border:1px solid var(--border);background:var(--bg-card);color:var(--text);cursor:pointer;flex-shrink:0}.theme-toggle:hover{border-color:var(--border-strong)}.theme-toggle svg{width:18px;height:18px}.theme-toggle .icon-moon{display:none}:root[data-theme=dark] .theme-toggle .icon-sun{display:none}:root[data-theme=dark] .theme-toggle .icon-moon{display:block}@media(min-width:720px){.site-header{padding:14px 32px}.nav-links{display:flex}}.hero{padding:2px 16px 0;text-align:center}.hero h1{font-size:clamp(1.2rem,4.6vw,2rem);font-weight:800;letter-spacing:-.01em}.hero p{margin-top:2px;font-size:10.5px;color:var(--text-muted);max-width:34em;margin-left:auto;margin-right:auto;line-height:1.2}@media(min-width:720px){.hero{padding:36px 16px 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p{font-size:12px;color:var(--text-faint);line-height:1.7}.notfound{padding:64px 16px;text-align:center}.notfound h1{font-size:clamp(2rem,8vw,3.5rem);font-weight:800}.notfound p{margin-top:12px;color:var(--text-muted);font-size:15px}.notfound a{display:inline-block;margin-top:20px;font-weight:700}