:root{
--primary:#2563eb;
--bg:#ffffff;
--bg-soft:#f8fafc;
--surface:#ffffff;
--control:#f1f5f9;
--hover:#eef2ff;
--text:#1e293b;
--muted:#64748b;
--border:#e2e8f0;
--shadow:rgba(15,23,42,.12);
color-scheme:light;
}

:root[data-theme="dark"]{
--primary:#60a5fa;
--bg:#0f172a;
--bg-soft:#111c31;
--surface:#182235;
--control:#243047;
--hover:#1e3a5f;
--text:#e5edf8;
--muted:#a9b7ca;
--border:#334155;
--shadow:rgba(0,0,0,.4);
color-scheme:dark;
}

*{margin:0;padding:0;box-sizing:border-box;}
body{font-family:Arial,sans-serif;background:var(--bg);color:var(--text);line-height:1.6;}
a{color:var(--primary);}

.topbar{
position:sticky;top:0;z-index:1000;display:flex;justify-content:space-between;align-items:center;
padding:15px 24px;background:var(--surface);border-bottom:1px solid var(--border);
}
.topbar-brand{display:flex;align-items:center;gap:12px;}
.logo a{display:flex;align-items:center;gap:12px;text-decoration:none;color:inherit;}
.logo-image{display:block;width:220px;max-width:34vw;height:52px;object-fit:contain;object-position:left center;}
.logo-mark{display:inline-flex;align-items:center;justify-content:center;width:42px;height:42px;border-radius:10px;background:var(--primary);color:#fff;font-weight:800;letter-spacing:.5px;}
.logo-mark.small{width:28px;height:28px;border-radius:7px;font-size:12px;}
.logo-word{font-size:22px;font-weight:800;}
.logo-label{padding-left:12px;border-left:1px solid var(--border);font-size:14px;font-weight:600;color:var(--muted);white-space:nowrap;}
.topbar-actions{display:flex;align-items:center;gap:10px;}

.search-wrapper{position:relative;}
#searchInput{width:280px;padding:10px 14px;border:1px solid var(--border);border-radius:8px;background:var(--surface);color:var(--text);}
#searchResults{display:none;position:absolute;top:48px;left:0;width:100%;background:var(--surface);border:1px solid var(--border);border-radius:10px;overflow:hidden;box-shadow:0 10px 30px var(--shadow);z-index:10001;}
#searchResults a{display:block;padding:12px 15px;text-decoration:none;color:var(--text);}
#searchResults a:hover{background:var(--hover);}
#searchResults small{display:block;margin-top:4px;color:var(--muted);}

.language-switcher{padding:10px 12px;border:1px solid var(--border);border-radius:8px;background:var(--surface);color:var(--text);}
#themeToggle,.menu-toggle{width:42px;height:42px;border:none;border-radius:8px;cursor:pointer;background:var(--control);color:var(--text);}
.menu-toggle{display:none;font-size:22px;}

.layout{display:flex;min-height:calc(100vh - 70px);}
.sidebar{width:280px;flex-shrink:0;padding:24px;background:var(--bg-soft);border-right:1px solid var(--border);position:sticky;top:70px;height:calc(100vh - 70px);overflow-y:auto;}
.sidebar ul{list-style:none;}
.sidebar h3{margin-top:20px;margin-bottom:10px;font-size:16px;}
.sidebar a{display:block;padding:8px 10px;border-radius:8px;text-decoration:none;color:var(--text);}
.sidebar a:hover{background:var(--hover);color:var(--primary);}
.sidebar a.active{background:var(--hover);color:var(--primary);font-weight:700;}
.close-sidebar{display:none;}

.content{flex:1;max-width:1000px;padding:40px 50px;}
.content h1{font-size:38px;line-height:1.15;margin-bottom:18px;}
.article-content{line-height:1.8;}
.article-content p{margin-bottom:16px;}
.article-content h2{margin-top:30px;margin-bottom:12px;scroll-margin-top:95px;}
.article-content ul,.article-content ol{margin:10px 0 18px 24px;}
.article-content li{margin-bottom:8px;}
.article-content table{width:100%;border-collapse:collapse;background:var(--bg);margin:20px 0 28px;}
.article-content th,.article-content td{padding:12px 14px;border:1px solid var(--border);text-align:left;vertical-align:top;}
.article-content th{background:var(--bg-soft);font-weight:700;}
.article-content code{font-family:Consolas,monospace;font-size:.9em;color:var(--primary);}

.hero{margin-bottom:40px;}
.hero h1{font-size:48px;letter-spacing:0;}
.hero p{max-width:760px;color:var(--muted);font-size:18px;}
.eyebrow{display:inline-block;margin-bottom:10px;color:var(--primary);font-weight:800;}
.quick-links{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:16px;margin:30px 0;}
.card{display:block;padding:20px;border:1px solid var(--border);border-radius:12px;text-decoration:none;color:inherit;transition:.2s;background:var(--surface);}
.card:hover{transform:translateY(-2px);box-shadow:0 10px 25px var(--shadow);}
.card small{display:block;color:var(--muted);margin-top:8px;}
.popular-articles{margin:12px 0 0 20px;}

.breadcrumb{display:flex;align-items:center;gap:8px;flex-wrap:wrap;font-size:14px;color:var(--muted);margin-bottom:15px;}
.breadcrumb a{text-decoration:none;color:var(--primary);}
.table-of-contents{margin:0 0 30px;padding:18px 20px;border:1px solid var(--border);border-radius:8px;background:var(--bg-soft);}
.table-of-contents h2{margin:0 0 10px;font-size:18px;line-height:1.3;}
.table-of-contents ol{margin:0;padding-left:22px;columns:1;}
.table-of-contents li{break-inside:avoid;margin:6px 0;color:var(--muted);}
.table-of-contents a{text-decoration:none;color:var(--primary);}
.table-of-contents a:hover{text-decoration:underline;}
.article-navigation{display:flex;justify-content:space-between;gap:20px;margin-top:50px;padding-top:30px;border-top:1px solid var(--border);}
.article-navigation a{text-decoration:none;padding:12px 16px;border:1px solid var(--border);border-radius:10px;color:var(--primary);display:inline-block;}
.article-navigation a:hover{background:var(--hover);}

.footer{margin-top:40px;border-top:1px solid var(--border);padding:20px;}
.footer-content{display:flex;justify-content:space-between;align-items:center;gap:20px;color:var(--muted);}
.footer-brand{display:flex;align-items:center;gap:8px;white-space:nowrap;color:var(--text);font-weight:800;}
.footer-logo-image{display:block;width:150px;height:36px;object-fit:contain;object-position:left center;}
.footer-slogan{font-size:13px;font-weight:600;color:var(--muted);white-space:normal;}
.footer-links{display:flex;justify-content:center;gap:16px;padding:0 20px 20px;}
.footer-links a{color:var(--primary);text-decoration:none;}
.footer-links a:hover{text-decoration:underline;}
.error-page{text-align:center;padding-top:80px;}
.error-code{font-size:72px;font-weight:800;line-height:1;color:var(--primary);}
.error-home{display:inline-block;margin-top:24px;padding:10px 16px;border-radius:8px;background:var(--primary);color:#fff;text-decoration:none;}

.sidebar-overlay{position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,.45);z-index:99998;opacity:0;visibility:hidden;transition:.3s;}
.sidebar-overlay.active{opacity:1;visibility:visible;}

@media (max-width:768px){
.menu-toggle{display:block;}
.topbar{display:block;padding:15px;}
.topbar-brand{margin-bottom:12px;}
.logo a{gap:8px;}
.logo-image{width:168px;max-width:48vw;height:42px;}
.logo-word{font-size:19px;}
.logo-label{padding-left:8px;font-size:12px;}
.topbar-actions{display:flex;align-items:center;gap:8px;}
#searchInput{width:100%;}
.search-wrapper{flex:1;}
.language-switcher{width:110px;}
.layout{display:block;}
.close-sidebar{display:block;width:40px;height:40px;border:none;border-radius:8px;background:var(--control);color:var(--text);cursor:pointer;font-size:20px;margin-bottom:20px;}
.sidebar{position:fixed;left:-300px;top:0;width:280px;height:100vh;background:var(--surface);z-index:99999;overflow-y:auto;box-shadow:0 0 20px var(--shadow);transition:left .3s ease;}
.sidebar.active{left:0;}
.content{width:100%;max-width:100%;padding:20px;}
.content h1{font-size:30px;}
.hero h1{font-size:36px;}
.hero p{font-size:16px;}
.footer-content{flex-direction:column;gap:10px;text-align:center;}
.footer-brand{justify-content:center;flex-direction:column;white-space:normal;}
.article-navigation{flex-direction:column;}
.table-of-contents ol{columns:1;}
}