@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');
[data-theme="dark"]{--bg:#0f0f14;--bg-surface:#16161d;--bg-card:#1e1e28;--bg-input:#1a1a24;--border:#2a2a3a;--text:#e8e8ef;--text-secondary:#a0a0b8;--text-muted:#6b6b80;--accent:#6366f1;--accent-subtle:rgba(99,102,241,0.12);--success:#10b981;--danger:#ef4444;--warning:#f59e0b;--glass-bg:rgba(30,30,40,0.7);--glass-border:rgba(255,255,255,0.08);--str-color:#10b981;--num-color:#f59e0b;--bool-color:#8b5cf6;--null-color:#6b7280;--key-color:#3b82f6}
[data-theme="light"]{--bg:#f5f5f7;--bg-surface:#fff;--bg-card:#fff;--bg-input:#f8f8fc;--border:#e0e0e8;--text:#1a1a2e;--text-secondary:#4a4a60;--text-muted:#8888a0;--accent:#6366f1;--glass-bg:rgba(255,255,255,0.75);--glass-border:rgba(0,0,0,0.06);--str-color:#059669;--num-color:#d97706;--bool-color:#7c3aed;--null-color:#6b7280;--key-color:#2563eb}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
body{font-family:'Inter',sans-serif;background:var(--bg);color:var(--text);min-height:100vh}
.container{max-width:1200px;margin:0 auto;padding:0 1rem}
.navbar{position:sticky;top:0;z-index:200;backdrop-filter:blur(16px);background:var(--glass-bg);border-bottom:1px solid var(--glass-border);padding:.4rem 0}
.nav-inner{display:flex;align-items:center;justify-content:space-between}
.brand{font-weight:700;font-size:1.1rem;color:var(--text);text-decoration:none}
.glass-card{background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:12px;padding:1rem;backdrop-filter:blur(12px)}
.btn{display:inline-flex;align-items:center;padding:.4rem .8rem;border:none;border-radius:6px;font-weight:600;font-size:.8rem;cursor:pointer;transition:all .15s}
.btn-primary{background:linear-gradient(135deg,#6366f1,#8b5cf6);color:#fff}
.btn-secondary{background:var(--bg-card);color:var(--text);border:1px solid var(--border)}
.btn-sm{padding:.3rem .6rem;font-size:.75rem}
.hidden{display:none!important}
.theme-btn{background:var(--bg-card);border:1px solid var(--border);border-radius:6px;padding:2px 8px;cursor:pointer;font-size:1rem}
.nav-links{display:flex;gap:.5rem}

.top-bar{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:.5rem;margin-bottom:.75rem}
.tabs{display:flex;gap:2px}
.tab{background:var(--bg-card);color:var(--text-secondary);border:1px solid var(--border);padding:.4rem .8rem;font-size:.8rem;font-weight:600;cursor:pointer;border-radius:6px;transition:all .15s}
.tab.active{background:var(--accent);color:#fff;border-color:var(--accent)}
.top-actions{display:flex;gap:.3rem}

.split-pane{display:grid;grid-template-columns:1fr 1fr;gap:.75rem;min-height:400px}
.pane{display:flex;flex-direction:column}
.pane-header{display:flex;justify-content:space-between;align-items:center;padding:.3rem 0;font-size:.8rem;font-weight:600;color:var(--text-muted);margin-bottom:.3rem;gap:.3rem}
textarea,.mono-input{width:100%;flex:1;resize:vertical;padding:.75rem;font-family:'JetBrains Mono',monospace;font-size:.8rem;line-height:1.5;background:var(--bg-input);color:var(--text);border:1px solid var(--border);border-radius:8px;outline:none;min-height:200px}
textarea:focus{border-color:var(--accent)}
input[type="text"]{padding:.5rem;background:var(--bg-input);color:var(--text);border:1px solid var(--border);border-radius:6px;font-family:'JetBrains Mono',monospace;font-size:.85rem;width:100%}
label{font-size:.8rem;color:var(--text-muted);margin-bottom:.5rem;display:flex;flex-direction:column;gap:.3rem}

.tree-view{flex:1;overflow:auto;padding:.5rem;background:var(--bg-input);border-radius:8px;border:1px solid var(--border);font-family:'JetBrains Mono',monospace;font-size:.8rem;line-height:1.6;min-height:200px}
.tree-node{padding-left:1.2rem}
.tree-key{color:var(--key-color);cursor:pointer}
.tree-key:hover{text-decoration:underline}
.tree-str{color:var(--str-color)}
.tree-num{color:var(--num-color)}
.tree-bool{color:var(--bool-color)}
.tree-null{color:var(--null-color);font-style:italic}
.tree-toggle{cursor:pointer;user-select:none;color:var(--text-muted);margin-right:.3rem}
.tree-bracket{color:var(--text-muted)}
.collapsed>.tree-node{display:none}

.result-box{padding:.75rem;background:var(--bg-input);border:1px solid var(--border);border-radius:8px;font-family:'JetBrains Mono',monospace;font-size:.8rem;min-height:100px;max-height:400px;overflow:auto;white-space:pre-wrap;line-height:1.5}
.format-actions{display:flex;gap:.3rem;margin-bottom:.5rem}
.stats-bar{font-size:.8rem;color:var(--text-muted);padding:.5rem 1rem}
.diff-add{background:rgba(16,185,129,0.15);color:var(--success)}
.diff-del{background:rgba(239,68,68,0.15);color:var(--danger)}
.diff-line{padding:1px 4px;border-radius:2px}
@media(max-width:768px){.split-pane{grid-template-columns:1fr}}