:root {
  --bg: #f4f5f9;
  --card: #ffffff;
  --fg: #2b2b2b;
  --fg2: #4f5b66;
  --fg3: #757575;
  --border: #dbdbdb;
  --primary: #0c2451;
  --sidebar: 264px;
  --font: -apple-system, BlinkMacSystemFont, "PingFang TC", "Noto Sans TC", "Helvetica Neue", Arial, sans-serif;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; height: 100%; }
body {
  font-family: var(--font);
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

.layout { display: grid; grid-template-columns: var(--sidebar) 1fr; min-height: 100vh; }
.sidebar {
  position: sticky; top: 0; height: 100vh;
  background: #111111; display: flex; flex-direction: column;
}
.side-brand { padding: 18px; border-bottom: 1px solid rgba(255,255,255,0.2); }
.side-brand strong { color: #fff; font-size: 14px; }
.nav { flex: 1; overflow-y: auto; padding: 12px 10px; }
.nav-group { margin-bottom: 14px; }
.nav-group-label {
  font-size: 10px; font-weight: 700; color: rgba(255,255,255,0.54);
  text-transform: uppercase; letter-spacing: 0.07em; padding: 4px 10px 7px;
}
.nav-item {
  width: 100%; display: block; text-align: left; padding: 8px 10px;
  border: 1px solid transparent; background: transparent; border-radius: 6px;
  cursor: pointer; font-family: inherit; font-size: 13px; font-weight: 500;
  color: rgba(255,255,255,0.82); margin-bottom: 2px;
}
.nav-item:hover { background: rgba(255,255,255,0.1); color: #fff; }
.nav-item.active { background: #fff; color: #111; font-weight: 700; }
.logout-btn {
  margin: 12px; padding: 9px; border: 1px solid rgba(255,255,255,0.25);
  background: transparent; color: rgba(255,255,255,0.8); border-radius: 6px; cursor: pointer;
}
.logout-btn:hover { background: rgba(255,255,255,0.1); color: #fff; }

.main { min-width: 0; display: flex; flex-direction: column; }
.topbar {
  position: sticky; top: 0; background: #fff; border-bottom: 1px solid var(--border);
  padding: 14px 28px; font-size: 14px; color: var(--primary); font-weight: 700;
}
.content { padding: 28px; max-width: 900px; margin: 0 auto; width: 100%; line-height: 1.7; }
.content h1 { font-size: 22px; margin: 0 0 8px; color: var(--primary); }
.content h2, .content h3, .content h4 { color: var(--primary); margin-top: 24px; }
.content p { color: var(--fg2); }
.content code {
  background: #eef0f5; padding: 1px 5px; border-radius: 4px; font-size: 0.92em;
}
.content ul, .content ol { padding-left: 20px; }
.content img { max-width: 100%; height: auto; border-radius: 8px; margin: 12px 0; display: block; }
.content table { width: 100%; border-collapse: collapse; margin: 14px 0; font-size: 13px; }
.content th, .content td { border: 1px solid var(--border); padding: 8px 10px; text-align: left; }
.content thead th { background: #eef0f5; color: var(--primary); }
.content tbody tr:nth-child(even) { background: #fafbfd; }

.auth-body { display: flex; align-items: center; justify-content: center; min-height: 100vh; }
.auth-card {
  background: var(--card); border: 1px solid var(--border); border-radius: 10px;
  padding: 32px; width: 320px; display: flex; flex-direction: column; gap: 12px;
}
.auth-card h1 { font-size: 18px; margin: 0; color: var(--primary); }
.auth-sub { margin: 0; color: var(--fg3); font-size: 13px; }
.auth-card label { display: flex; flex-direction: column; gap: 4px; font-size: 13px; color: var(--fg2); }
.auth-card input {
  padding: 9px 10px; border: 1px solid var(--border); border-radius: 6px; font-size: 14px;
}
.auth-card button {
  margin-top: 6px; padding: 10px; border: none; border-radius: 6px;
  background: var(--primary); color: #fff; font-weight: 700; cursor: pointer;
}
.auth-error { color: #b3261e; font-size: 13px; min-height: 18px; margin: 0; }

#editForm { display: flex; flex-direction: column; gap: 12px; max-width: 720px; }
#editForm label { display: flex; flex-direction: column; gap: 4px; font-size: 13px; color: var(--fg2); }
#editForm input, #editForm textarea {
  padding: 9px 10px; border: 1px solid var(--border); border-radius: 6px; font-family: inherit; font-size: 14px;
}
#editForm textarea { font-family: "SF Mono", ui-monospace, Menlo, Consolas, monospace; font-size: 13px; }
.upload-row { display: flex; align-items: center; gap: 10px; }
.upload-row button {
  padding: 7px 14px; border: 1px solid var(--border); border-radius: 6px;
  background: #fff; color: var(--primary); font-weight: 600; cursor: pointer;
}
.upload-row span { font-size: 12px; color: var(--fg3); }
#editForm button[type="submit"] {
  align-self: flex-start; padding: 9px 18px; border: none; border-radius: 6px;
  background: var(--primary); color: #fff; font-weight: 700; cursor: pointer;
}