:root {
  --primary: #10B981; --primary-hover: #059669; --secondary: #34D399;
  --accent: #8B5CF6; --success: #10B981; --error: #EF4444; --warning: #F59E0B;
  --bg: #0A1A14; --bg-elevated: #0F251B; --bg-card: #142E22;
  --bg-input: #0C1F18; --text: #E0F5EC; --text-muted: #80B8A0; --text-dim: #446B58;
  --border: #1E3D30; --border-hover: #2D5A48; --radius: 12px; --radius-sm: 8px;
  --font: 'Inter', system-ui, sans-serif; --mono: monospace; --transition: 200ms ease;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
body{font-family:var(--font);background:var(--bg);color:var(--text);min-height:100vh;overflow:hidden}
.app{display:flex;flex-direction:column;height:100vh}

.header{display:flex;align-items:center;justify-content:space-between;padding:12px 20px;background:var(--bg-elevated);border-bottom:1px solid var(--border);gap:12px;flex-shrink:0}
.header-left{display:flex;align-items:center;gap:12px}
.logo{font-size:1.3rem}
.header-title{font-size:1.05rem;font-weight:700;background:linear-gradient(135deg,var(--primary),var(--secondary));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.header-right{display:flex;gap:8px}

.btn{display:inline-flex;align-items:center;gap:6px;padding:8px 14px;font-size:.8rem;font-weight:500;font-family:var(--font);border:none;border-radius:var(--radius-sm);cursor:pointer;transition:all var(--transition);white-space:nowrap}
.btn:disabled{opacity:.4;cursor:not-allowed}
.btn-primary{background:linear-gradient(135deg,var(--primary),var(--primary-hover));color:#0A1A14;font-weight:700;box-shadow:0 2px 8px rgba(16,185,129,.3)}
.btn-primary:hover{transform:translateY(-1px);box-shadow:0 4px 16px rgba(16,185,129,.4)}
.btn-ghost{background:transparent;color:var(--text-muted);border:1px solid var(--border)}
.btn-ghost:hover:not(:disabled){background:var(--bg-card);color:var(--text);border-color:var(--border-hover)}
.btn-sm{padding:5px 10px;font-size:.72rem}

.main{display:grid;grid-template-columns:1fr 1fr;flex:1;overflow:hidden;gap:1px;background:var(--border)}
.panel{display:flex;flex-direction:column;background:var(--bg);overflow:hidden;padding:12px;gap:8px}
.panel-title{font-size:.82rem;font-weight:600}

.code-editor{flex:1;padding:14px;font-family:var(--mono);font-size:.78rem;line-height:1.6;background:var(--bg-input);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--secondary);resize:none;outline:none;tab-size:2}
.code-editor:focus{border-color:var(--primary)}
.code-editor::placeholder{color:var(--text-dim)}

.tabs{display:flex;gap:0;border-bottom:1px solid var(--border)}
.tab{padding:8px 14px;font-size:.72rem;font-weight:500;font-family:var(--font);color:var(--text-dim);background:none;border:none;border-bottom:2px solid transparent;cursor:pointer;transition:all var(--transition)}
.tab:hover{color:var(--text-muted)}
.tab.active{color:var(--primary);border-bottom-color:var(--primary)}
.tab-content{display:none;flex:1;overflow-y:auto;padding:12px 0}
.tab-content.active{display:flex;flex-direction:column;gap:8px}

.preview{font-size:.8rem;line-height:1.6}
.placeholder{color:var(--text-dim);font-style:italic}

.rich-card{padding:16px;background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);display:flex;flex-direction:column;gap:6px}
.rich-type{font-size:.65rem;font-weight:700;padding:2px 8px;border-radius:4px;background:var(--primary);color:#0A1A14;align-self:flex-start}
.rich-title{font-size:1rem;font-weight:700;color:var(--secondary)}
.rich-meta{font-size:.72rem;color:var(--text-muted)}

.issues{display:flex;flex-direction:column;gap:4px}
.issue-row{padding:8px 12px;border-radius:var(--radius-sm);font-size:.75rem;display:flex;align-items:flex-start;gap:8px}
.issue-row.error{background:rgba(239,68,68,.06);border-left:3px solid var(--error);color:var(--error)}
.issue-row.warning{background:rgba(245,158,11,.06);border-left:3px solid var(--warning);color:var(--warning)}
.issue-row.success{background:rgba(16,185,129,.06);border-left:3px solid var(--success);color:var(--success)}
.issue-icon{flex-shrink:0}

.tree{font-family:var(--mono);font-size:.72rem;line-height:1.8}
.tree-node{padding-left:16px;border-left:1px solid var(--border)}
.tree-key{color:var(--primary);font-weight:600}
.tree-val{color:var(--text-muted)}

.toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);padding:10px 20px;background:var(--bg-card);border:1px solid var(--primary);border-radius:var(--radius-sm);color:var(--primary);font-size:.8rem;font-weight:500;z-index:200;animation:toast-in .3s ease}
@keyframes toast-in{from{opacity:0;transform:translateX(-50%) translateY(10px)}to{opacity:1;transform:translateX(-50%) translateY(0)}}
::-webkit-scrollbar{width:6px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:3px}
@media(max-width:768px){.main{grid-template-columns:1fr;grid-template-rows:1fr 1fr}}