:root{--bg:#f4f5f7;--card:#fff;--text:#1f2328;--muted:#6b7280;--primary:#2563eb;--border:#e5e7eb}
*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,"Noto Sans",sans-serif}
.app-header{display:flex;justify-content:space-between;align-items:center;padding:16px 24px;background:#fff;border-bottom:1px solid var(--border)}
.brand{font-weight:600}
.link-btn{padding:8px 12px;border-radius:8px;background:#eef2ff;color:#3730a3;text-decoration:none}
.app-main{display:flex;gap:16px;padding:16px;height:calc(100vh - 64px)}
.panel{width:380px;display:flex;flex-direction:column;gap:16px;overflow:auto}
.card{background:var(--card);border:1px solid var(--border);border-radius:12px;padding:16px}
.card-title{margin:0 0 12px 0;font-size:16px}
.upload .btn{display:inline-block;background:var(--primary);color:#fff;border:none;border-radius:10px;padding:10px 14px;cursor:pointer}
.file-name{margin-top:8px;color:var(--muted);font-size:12px}
.grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.field{display:flex;flex-direction:column;gap:6px}
.input-group{display:flex;align-items:center;gap:6px}
.field input[type=number],.field input[type=color],.field select,textarea{width:100%;padding:8px;border:1px solid var(--border);border-radius:8px;background:#fff}
textarea{resize:vertical}
.actions{display:flex;gap:8px;margin-top:12px}
.btn{padding:8px 12px;border-radius:8px;border:1px solid var(--border);background:#fff;cursor:pointer}
.btn.primary{background:var(--primary);border-color:var(--primary);color:#fff}
.error{margin-top:8px;color:#ef4444;font-size:12px;min-height:18px}
.preview{flex:1;background:var(--card);border:1px solid var(--border);border-radius:12px;display:flex;align-items:center;justify-content:center;position:relative;height:100%}
.empty{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;color:var(--muted)}
.empty-icon{font-size:36px;margin-bottom:8px}
#canvas{max-width:100%;max-height:100%;display:none;border-radius:12px}