:root {
  --bg: #f8fafc; --panel: #ffffff; --text: #111827; --muted: #4b5563; --accent: #2563eb; --danger: #dc2626; --ring: #3b82f6;
}
*{box-sizing:border-box;}html,body{margin:0;padding:0;background:var(--bg);color:var(--text);font:16px/1.5 system-ui,sans-serif;}
.app-header,.app-footer{padding:12px 16px;background:var(--panel);border-bottom:1px solid #d1d5db;}
.app-footer{border-top:1px solid #d1d5db;border-bottom:none;}
h1{margin:0 0 8px;font-size:1.25rem;}h2{margin:0 0 8px;font-size:1rem;}h3{margin:0;font-size:0.95rem;}
.muted{color:var(--muted);margin:6px 0 8px;}
#add-card-form{display:flex;gap:8px;align-items:center;}
#add-card-form input{flex:1;padding:8px 10px;border:1px solid #d1d5db;border-radius:8px;background:#ffffff;color:var(--text);}
#add-card-form button{padding:8px 12px;border:1px solid #cbd5f5;background:#e2e8f0;color:var(--text);border-radius:8px;cursor:pointer;}
.board{display:grid;gap:12px;padding:16px;min-height:calc(100vh - 140px);grid-template-columns:repeat(auto-fit,minmax(220px,1fr));}
.column{background:var(--panel);border:1px solid #d1d5db;border-radius:12px;padding:12px;outline:none;}
.card-list{display:grid;gap:10px;min-height:80px;padding:6px;border:1px dashed #cbd5f5;border-radius:8px;}
.card{background:#ffffff;border:1px solid #d1d5db;border-radius:10px;padding:10px;}
.card-actions{display:flex;gap:8px;margin-top:8px;}
.card-actions button{padding:6px 8px;border-radius:6px;border:1px solid #cbd5f5;background:#e2e8f0;color:var(--text);cursor:pointer;}
.card-actions .danger{border-color:#fca5a5;}
#board-controls{display:flex;justify-content:flex-end;align-items:center;padding:8px 16px 0;gap:12px;}
.column-add-control{display:flex;align-items:center;gap:12px;}
.column-add-label{font-weight:600;}
.column-add-control button{width:40px;height:40px;border-radius:50%;border:1px solid #cbd5f5;background:#ffffff;color:var(--accent);font-size:1.5rem;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:background .2s ease,color .2s ease;}
.column-add-control button:focus-visible{outline:2px solid var(--ring);outline-offset:2px;}
.column-add-control button:hover{background:var(--accent);color:#ffffff;}
.column-add-message{margin:0;font-size:0.85rem;color:var(--muted);}
.column-add-control[data-state="error"] .column-add-message{color:var(--danger);}
.column-add-control[data-state="success"] .column-add-message{color:var(--accent);}
.column-background-control{display:flex;align-items:center;gap:8px;margin-bottom:8px;}
.column-background-label{font-size:0.85rem;color:var(--muted);}
.column-background-select{flex:1;min-width:0;padding:4px 6px;border:1px solid #cbd5f5;border-radius:6px;background:#ffffff;color:var(--text);}
.column-background-select:focus-visible{outline:2px solid var(--ring);outline-offset:2px;}
.card-editor-overlay{position:fixed;inset:0;display:flex;align-items:center;justify-content:center;padding:16px;background:rgba(15,23,42,.35);z-index:50;}
.card-editor-overlay[hidden]{display:none;}
.card-editor-dialog{background:var(--panel);border-radius:12px;box-shadow:0 18px 40px rgba(15,23,42,.25);max-width:420px;width:100%;padding:20px;border:1px solid #d1d5db;display:flex;flex-direction:column;gap:12px;}
.card-editor-heading{margin:0;font-size:1.05rem;}
.card-editor-form{display:flex;flex-direction:column;gap:10px;}
.card-editor-label{font-size:0.85rem;font-weight:600;color:var(--muted);}
.card-editor-input,.card-editor-textarea{width:100%;padding:8px 10px;border:1px solid #cbd5f5;border-radius:8px;background:#ffffff;color:var(--text);font:inherit;}
.card-editor-textarea{resize:vertical;min-height:90px;}
.card-editor-actions{display:flex;justify-content:flex-end;gap:8px;margin-top:4px;}
.card-editor-save,.card-editor-cancel{padding:8px 12px;border-radius:8px;border:1px solid #cbd5f5;background:#e2e8f0;color:var(--text);cursor:pointer;}
.card-editor-save{background:var(--accent);color:#ffffff;border-color:var(--accent);}
.card-editor-save:focus-visible,.card-editor-cancel:focus-visible{outline:2px solid var(--ring);outline-offset:2px;}
.card-editor-error{margin:0;color:var(--danger);font-size:0.85rem;min-height:1em;}