:root[data-theme="light"] {
  --bg:#f5f5f5; --fg:#222; --card:#fff; --border:#ccc;
}
:root[data-theme="dark"] {
  --bg:#121212; --fg:#eee; --card:#1e1e1e; --border:#444;
}
body{font-family:system-ui,sans-serif;margin:0;padding:1rem;background:var(--bg);color:var(--fg)}
.screen{max-width:600px;margin:auto}
.hidden{display:none}
#feed-input{width:100%;height:100px}
.feed-item,.item-card{border:1px solid var(--border);background:var(--card);padding:.5rem;margin:.5rem 0;cursor:pointer}
.flex{display:flex}
.justify-between{justify-content:space-between}
.items-center{align-items:center}
.mb-2{margin-bottom:.5rem}
.mb-3{margin-bottom:1rem}
button{background:#0066ff;color:#fff;border:none;padding:.4rem .8rem;cursor:pointer}
button:hover{opacity:.9}