:root{
  --bg:#0b0f1a;
  --panel:#0f1424;
  --panel-2:#121a2e;
  --text:#dfe7ff;
  --muted:#9fb0d3;
  --acc:#00ffd5;
  --acc-2:#7b2cff;
  --border:#1d2642;
  --green:#1ed760;
  --red:#ff4d4d;
}

*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  background:linear-gradient(180deg, #0b0f1a, #0a0e1a);
  color:var(--text);
  font:14px/1.45 system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
}

/* Header */
.app-header{
  display:flex; align-items:center; justify-content:space-between;
  padding:12px 16px;
  border-bottom:1px solid var(--border);
  background:linear-gradient(90deg, rgba(0,255,213,.07), rgba(123,44,255,.07));
  backdrop-filter: blur(4px);
  position:sticky; top:0; z-index:10;
}
.logo{display:flex; align-items:center; gap:10px; font-weight:700; letter-spacing:.5px}
.logo svg{width:32px; height:32px; display:block; filter:drop-shadow(0 0 8px rgba(0,255,213,.35))}
.logo span{font-size:16px}

/* Buttons */
.btn, .btn-file{
  background:var(--panel); border:1px solid var(--border); color:var(--text);
  padding:8px 10px; border-radius:10px; cursor:pointer;
  transition:.15s transform, .15s background, .15s border-color;
}
.btn:hover,.btn-file:hover{background:var(--panel-2); border-color:#273154}
.btn:active{transform:translateY(1px)}
.btn.primary{background:linear-gradient(90deg,var(--acc),var(--acc-2)); color:#081019; font-weight:700; border:none}
.btn.primary:hover{filter:brightness(1.05)}
.btn.btn-ghost{background:transparent; border-color:transparent; color:var(--muted)}
.btn.btn-ghost:hover{border-color:var(--border); color:var(--text)}
.btn-file{position:relative; overflow:hidden}
.btn-file input[type=file]{position:absolute; inset:0; opacity:0; cursor:pointer}

.header-actions{display:flex; gap:8px; flex-wrap:wrap}

/* Layout */
.layout{display:grid; grid-template-columns:280px 1fr; gap:0; height:calc(100vh - 64px)}
.sidebar{
  background:var(--panel);
  border-right:1px solid var(--border);
  display:flex; flex-direction:column; min-width:240px;
}
.sidebar-top{padding:10px}
.search{
  width:100%; padding:8px 10px; border-radius:10px;
  border:1px solid var(--border); background:#0c1222; color:var(--text);
}
.sidebar-hint{font-size:12px; color:var(--muted); padding:8px 10px; border-top:1px dashed var(--border)}
.tree{list-style:none; margin:0; padding:6px 6px 12px 6px; overflow:auto; flex:1}
.tree li{
  display:flex; align-items:center; gap:8px;
  padding:6px 8px; border-radius:8px; cursor:pointer; user-select:none;
}
.tree li:hover{background:rgba(255,255,255,.03)}
.tree li.active{background:rgba(0,255,213,.12); outline:1px solid rgba(0,255,213,.3)}
.node-label{flex:1; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; color:var(--text)}
.node-type{font-size:12px; color:var(--muted)}
.node-actions{display:none; gap:6px}
.tree li:hover .node-actions{display:flex}
.node-actions button{font-size:12px; padding:4px 6px}

.editor-pane{display:flex; flex-direction:column; min-width:0}
.editor-bar{
  display:flex; align-items:center; justify-content:space-between;
  padding:10px 12px; border-bottom:1px solid var(--border); background:var(--panel-2);
}
.path{font-family:ui-monospace, SFMono-Regular, Menlo, Monaco, "Liberation Mono", Consolas, monospace; color:var(--muted)}
.sep{width:1px; height:18px; background:var(--border); margin:0 6px}

.meta{
  display:grid; grid-template-columns:1fr 1fr; gap:10px; padding:10px 12px; background:#0c1222; border-bottom:1px solid var(--border);
}
.meta-group{display:flex; flex-direction:column; gap:6px}
.meta input{
  padding:8px; border-radius:8px; border:1px solid var(--border); background:#091224; color:var(--text);
}

.toolbar{
  display:flex; gap:6px; padding:8px 12px; background:var(--panel);
  border-bottom:1px solid var(--border);
}
.btn-compact{
  padding:6px 8px; background:#0c1222; border:1px solid var(--border); color:var(--text);
  border-radius:8px; cursor:pointer;
}
.btn-compact:hover{background:#0f1424}

#editor{
  flex:1; width:100%; border:0; outline:none; resize:none; padding:14px 16px;
  background:transparent; color:var(--text);
  font:13px/1.5 ui-monospace, SFMono-Regular, Menlo, Monaco, "Liberation Mono", Consolas, monospace;
}

.links{border-top:1px solid var(--border); background:var(--panel); padding:10px 12px}
.links-head{display:flex; align-items:center; justify-content:space-between; gap:10px}
.links-actions{display:flex; gap:8px}
#urlInput{
  min-width:320px; flex:1; padding:8px; border-radius:8px; border:1px solid var(--border); background:#0c1222; color:var(--text);
}
.url-list{list-style:none; margin:8px 0 0; padding:0; display:grid; gap:6px}
.url-list li{display:flex; align-items:center; justify-content:space-between; gap:10px; background:#0c1222; border:1px solid var(--border); border-radius:8px; padding:8px 10px}
.url-list a{color:var(--acc)}
.url-list button{padding:4px 6px}

.app-footer{
  padding:8px 12px; border-top:1px solid var(--border); color:var(--muted);
  background:var(--panel); font-size:12px;
}

/* Drag and drop cue */
.sidebar.drag-over{outline:2px dashed var(--acc); outline-offset:-6px}

/* Responsive */
@media (max-width: 960px){
  .layout{grid-template-columns:1fr}
  .sidebar{height:40vh; border-right:none; border-bottom:1px solid var(--border)}
  .editor-pane{height:calc(60vh - 0px)}
}