:root {
  --bg: #f4f5f7;
  --surface: #fff;
  --text: #222;
  --muted: #666;
  --border: #dcdfe4;
  --accent: #0b65d8;
  color-scheme: light;
}
:root[data-theme='dark'] {
  --bg: #111;
  --surface: #1e1e1e;
  --text: #e4e4e4;
  --muted: #9a9a9a;
  --border: #3a3a3a;
  --accent: #4a9eff;
  color-scheme: dark;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}
.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 880px;
  margin: 0 auto;
  padding: 24px 16px 0;
}
.top h1 { margin: 0; font-size: 26px; letter-spacing: 0.02em; }
#theme {
  font-size: 18px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px 10px;
  cursor: pointer;
}
main { max-width: 880px; margin: 0 auto; padding: 24px 16px 48px; }
.lead { color: var(--muted); margin: 0 0 12px; font-size: 14px; text-transform: uppercase; letter-spacing: 0.06em; }
.tools {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
}
.tool {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-rows: auto auto;
  column-gap: 14px;
  row-gap: 4px;
  height: 100%;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  color: inherit;
  text-decoration: none;
  transition: border-color 0.15s, transform 0.15s;
}
.tool:hover, .tool:focus-visible { border-color: var(--accent); transform: translateY(-2px); }
.icon { grid-row: span 2; font-size: 30px; line-height: 1; }
.name { font-size: 18px; font-weight: 600; color: var(--accent); }
.desc { color: var(--muted); font-size: 14px; line-height: 1.4; }

/* Header actions, sign-in, add user */
.top-actions { display: flex; align-items: center; gap: 10px; }
.top-actions button { font: inherit; font-size: 14px; color: inherit; }
#sign-out {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 7px 12px;
  cursor: pointer;
}
.muted { color: var(--muted); }
.small { font-size: 13px; }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
}
#signed-out .card { max-width: 380px; margin: 24px auto 0; }
.form { display: flex; flex-direction: column; gap: 12px; }
.form h2 { margin: 0; font-size: 20px; }
.form p { margin: 0; }
.form label { display: flex; flex-direction: column; gap: 4px; font-size: 14px; }
.form input {
  font: inherit;
  color: inherit;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 10px;
}
.form input:focus { outline: 2px solid var(--accent); outline-offset: -1px; }
button.primary {
  font: inherit;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 6px;
  padding: 9px 14px;
  cursor: pointer;
}
:root[data-theme='dark'] button.primary { color: #0b1320; }
button.primary:disabled { opacity: 0.6; cursor: default; }
.error { background: rgba(198, 40, 40, 0.12); color: #c62828; padding: 8px 10px; border-radius: 6px; font-size: 14px; }
.success { background: rgba(46, 125, 50, 0.12); color: #2e7d32; padding: 8px 10px; border-radius: 6px; font-size: 14px; }
:root[data-theme='dark'] .error { color: #ef6b6b; }
:root[data-theme='dark'] .success { color: #81c784; }
#add-user-panel { margin-top: 32px; max-width: 480px; }
#add-user-panel summary { cursor: pointer; font-weight: 600; }
#add-user-panel .form { margin-top: 14px; }
@media (max-width: 560px) {
  #who { display: none; }
}