:root{--bg: #f5f7fa;--bg-card: #ffffff;--bg-sidebar: #1e293b;--text: #1e293b;--text-secondary: #64748b;--text-sidebar: #cbd5e1;--text-sidebar-active: #ffffff;--border: #e2e8f0;--primary: #3b82f6;--primary-hover: #2563eb;--accent: #8b5cf6;--danger: #ef4444;--success: #22c55e;--shadow: 0 1px 3px rgba(0,0,0,.1);--shadow-lg: 0 4px 12px rgba(0,0,0,.1);--radius: 8px;--radius-lg: 12px;--transition: .2s ease}[data-theme=dark]{--bg: #0f172a;--bg-card: #1e293b;--bg-sidebar: #0f172a;--text: #e2e8f0;--text-secondary: #94a3b8;--text-sidebar: #94a3b8;--text-sidebar-active: #ffffff;--border: #334155;--primary: #60a5fa;--primary-hover: #3b82f6;--shadow: 0 1px 3px rgba(0,0,0,.3);--shadow-lg: 0 4px 12px rgba(0,0,0,.4)}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;scroll-behavior:smooth}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;background:var(--bg);color:var(--text);transition:background var(--transition),color 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var(--border)}.sf-collapse-header input[type=checkbox]{display:none}.sf-collapse-label{display:flex;align-items:center;gap:8px;cursor:pointer;font-size:1rem;font-weight:500;color:var(--text);-webkit-user-select:none;user-select:none}.sf-collapse-label:hover{color:var(--primary)}.sf-add-field{width:22px;height:22px;display:inline-flex;position:relative;color:var(--primary);border-radius:50%;border:2px solid var(--primary);flex-shrink:0}.sf-add-field:after{content:"";position:absolute;background:var(--primary);width:60%;height:2px;left:20%;top:50%;transform:translateY(-50%)}.sf-collapse-header input[type=checkbox]:checked+label .sf-add-field:after{display:none}.sf-add-field:before{content:"";position:absolute;background:var(--primary);width:2px;height:60%;left:50%;top:20%;transform:translate(-50%)}.sf-collapse-header input[type=checkbox]:checked+label .sf-add-field:before{display:none}.sf-collapse-body{padding:8px 0 8px 16px;border-left:2px solid var(--primary);margin-left:10px}.sf-note{padding:10px;background:var(--bg);border:1px solid var(--primary);border-radius:4px;font-size:.85rem;margin:10px 0;color:var(--text)}.sf-note-warn{font-style:italic}.sf-img-section{display:flex;justify-content:center;padding:16px 0}.sf-scheme-img{max-width:100%;height:auto;border-radius:4px}.sf-btn-group{display:grid;grid-template-columns:repeat(auto-fill,minmax(130px,1fr));gap:8px}.sf-btn-group-item{padding:8px 12px;border:2px solid var(--border);border-radius:6px;background:var(--bg);color:var(--text);font-size:.85rem;cursor:pointer;transition:all .15s;text-align:center}.sf-btn-group-item:hover{border-color:var(--primary);color:var(--primary)}.sf-btn-group-item.active{border-color:var(--primary);background:var(--primary);color:#fff}.sf-submit{display:flex;justify-content:center;padding:20px 0}.sf-btn{background:linear-gradient(to bottom,var(--primary),var(--primary-hover));border-radius:4px;border:none;padding:12px 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