:root{--primary: #2563eb;--primary-dark: #1e40af;--bg: #f5f6f8;--card: #ffffff;--text: #1f2329;--text-2: #646a73;--border: #e5e7eb;--radius: 10px;--maxw: 1080px}*{box-sizing:border-box}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Hiragino Sans GB,Microsoft YaHei,sans-serif;background:var(--bg);color:var(--text);line-height:1.6}a{color:var(--primary);text-decoration:none}a:hover{text-decoration:underline}.container{max-width:var(--maxw);margin:0 auto;padding:0 16px}.site-header{background:#fff;border-bottom:1px solid var(--border);position:sticky;top:0;z-index:10}.site-header .container{display:flex;align-items:center;gap:24px;min-height:56px;flex-wrap:wrap}.logo{font-size:20px;font-weight:700;color:var(--text);display:flex;align-items:center;gap:8px}.logo:hover{text-decoration:none}.nav{display:flex;gap:4px;flex-wrap:wrap}.nav a{color:var(--text-2);padding:6px 12px;border-radius:6px;font-size:15px}.nav a:hover{background:#f0f3f8;color:var(--primary);text-decoration:none}main{padding:24px 0 48px}.hero{text-align:center;padding:32px 0 8px}.hero h1{font-size:28px;margin:0 0 8px}.hero p{color:var(--text-2);margin:0}.cat-section{margin-top:36px}.cat-section h2{font-size:20px;margin:0 0 4px}.cat-desc{color:var(--text-2);font-size:14px;margin:0 0 16px}.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:12px}.tool-card{display:block;background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:16px;color:var(--text)}.tool-card:hover{border-color:var(--primary);box-shadow:0 2px 8px #2563eb1f;text-decoration:none}.tool-card h3{margin:0 0 6px;font-size:16px;color:var(--text)}.tool-card p{margin:0;font-size:13px;color:var(--text-2);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.breadcrumb{font-size:13px;color:var(--text-2);margin-bottom:16px}.tool-head h1{font-size:24px;margin:0 0 6px}.panel{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:20px;margin-bottom:20px}.prose h2{font-size:18px}.prose p,.prose li{font-size:15px;color:#3b4048}textarea{width:100%;min-height:180px;padding:10px 12px;border:1px solid var(--border);border-radius:8px;font-family:Consolas,Menlo,monospace;font-size:14px;resize:vertical}input[type=text],input[type=number],input[type=datetime-local],select{padding:8px 12px;border:1px solid var(--border);border-radius:8px;font-size:14px}textarea:focus,input:focus,select:focus{outline:none;border-color:var(--primary)}label.field{display:inline-flex;flex-direction:column;gap:4px;font-size:13px;color:var(--text-2);margin:0 12px 12px 0}.btn{display:inline-block;padding:8px 16px;border:1px solid var(--border);border-radius:8px;background:#fff;color:var(--text);font-size:14px;cursor:pointer}.btn:hover{border-color:var(--primary);color:var(--primary)}.btn-primary{background:var(--primary);border-color:var(--primary);color:#fff}.btn-primary:hover{background:var(--primary-dark);color:#fff}.btn-row{display:flex;gap:8px;flex-wrap:wrap;margin:12px 0;align-items:center}.result{background:#f8fafc;border:1px solid var(--border);border-radius:8px;padding:16px;font-size:15px}.error{background:#fef2f2;border:1px solid #fecaca;color:#b91c1c;border-radius:8px;padding:10px 14px;font-size:14px}table.data{width:100%;border-collapse:collapse;font-size:14px}table.data th,table.data td{border:1px solid var(--border);padding:8px 12px;text-align:left}table.data th{background:#f8fafc}.num{font-variant-numeric:tabular-nums;font-family:Consolas,Menlo,monospace}.faq details{border:1px solid var(--border);border-radius:8px;padding:0 16px;margin-bottom:8px;background:#fff}.faq summary{padding:12px 0;cursor:pointer;font-weight:600;font-size:15px}.faq details p{margin-top:0;color:var(--text-2);font-size:14px}.related{margin:32px 0}.muted{color:var(--text-2);font-size:13px}.site-footer{border-top:1px solid var(--border);background:#fff;padding:24px 0;color:var(--text-2);font-size:13px;text-align:center}.site-footer a{color:var(--text-2);margin:0 8px}@media(max-width:640px){.hero h1{font-size:22px}.site-header .container{gap:8px;padding:8px 16px}}