:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --line: #d8deed;
  --text: #1c2433;
  --muted: #5e6983;
  --primary: #114b8b;
  --danger: #8d1b1b;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: linear-gradient(120deg, #e7edf8, #f9fbff);
  color: var(--text);
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
}
.page {
  display: grid;
  grid-template-columns: 360px 1fr;
  min-height: 100vh;
}
.sidebar {
  padding: 16px;
  border-right: 1px solid var(--line);
  overflow-y: auto;
}
.content { padding: 20px; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px;
  margin-bottom: 12px;
}
input, textarea, button {
  width: 100%;
  margin: 6px 0;
  padding: 10px;
  border: 1px solid #cfd8ea;
  border-radius: 8px;
  font: inherit;
}
button {
  background: var(--primary);
  color: #fff;
  border: none;
  cursor: pointer;
}
button:disabled { opacity: .55; cursor: not-allowed; }
.notice {
  padding: 10px;
  border-radius: 8px;
  background: #eef7ff;
  border: 1px solid #b8d7ff;
}
.muted { color: var(--muted); }
.topics { list-style: none; padding: 0; margin: 0; }
.topics li { padding: 8px 0; border-bottom: 1px solid var(--line); }
.topics a { color: var(--primary); text-decoration: none; font-weight: 700; }
.topics small { display: block; color: var(--muted); margin-top: 3px; }
.post {
  background: #fff;
  border: 1px solid var(--line);
  border-left: 4px solid var(--primary);
  border-radius: 10px;
  padding: 10px;
  margin: 10px 0;
}
.post.system { border-left-color: var(--danger); background: #fff6f6; }
.post header {
  display: flex;
  justify-content: space-between;
  gap: 8px;
}
.inline-form { display: inline-block; margin-top: 6px; }
.inline-form button {
  width: auto;
  padding: 6px 10px;
  font-size: 12px;
}
.admin-user {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  border-bottom: 1px solid var(--line);
  padding: 6px 0;
}
.empty {
  padding: 30px;
  background: #fff;
  border: 1px dashed var(--line);
  border-radius: 12px;
  color: var(--muted);
}
@media (max-width: 980px) {
  .page { grid-template-columns: 1fr; }
  .sidebar { border-right: 0; border-bottom: 1px solid var(--line); }
}