:root {
  --bg: #f6f8fa;
  --card-bg: #ffffff;
  --border: #d0d7de;
  --text: #1f2328;
  --text-muted: #636c76;
  --accent: #0969da;
  --radius: 8px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1117;
    --card-bg: #161b22;
    --border: #30363d;
    --text: #e6edf3;
    --text-muted: #8b949e;
    --accent: #4493f8;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--card-bg);
}

.brand {
  font-weight: 600;
  font-size: 18px;
  color: var(--text);
  text-decoration: none;
}

.topnav {
  display: flex;
  align-items: center;
  gap: 16px;
}

.logout, .back-link, .nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
}
.logout:hover, .back-link:hover, .nav-link:hover { color: var(--accent); }

main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px;
}

.tabs { display: flex; gap: 4px; margin-bottom: 16px; }
.tab {
  padding: 6px 14px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--card-bg);
  color: var(--text-muted);
  cursor: pointer;
  font-size: 13px;
}
.tab:hover { border-color: var(--accent); }
.tab.active { color: var(--text); border-color: var(--accent); background: var(--bg); }

.toolbar { margin-bottom: 20px; display: flex; align-items: center; gap: 12px; }

#search {
  width: 100%;
  max-width: 420px;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card-bg);
  color: var(--text);
  font-size: 14px;
}

.tile-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
}

.tile {
  display: block;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card-bg);
  text-decoration: none;
  color: var(--text);
  transition: border-color 0.15s ease;
}
.tile:hover { border-color: var(--accent); }

.tile-id {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 12px;
  color: var(--accent);
  margin-bottom: 4px;
}

.tile-name {
  font-weight: 600;
  font-size: 15px;
  margin-bottom: 10px;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.tile-meta {
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-muted);
}

.empty-state {
  color: var(--text-muted);
  text-align: center;
  padding: 40px 0;
}

.auth-card {
  max-width: 340px;
  margin: 60px auto;
  padding: 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card-bg);
}
.auth-card h1 { font-size: 18px; margin: 0 0 16px; }
.auth-card form { display: flex; flex-direction: column; gap: 12px; }
.auth-card label { font-size: 13px; color: var(--text-muted); display: flex; flex-direction: column; gap: 4px; }
.auth-card input {
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
}
.auth-card button {
  padding: 8px 10px;
  border: none;
  border-radius: 6px;
  background: var(--accent);
  color: white;
  font-size: 14px;
  cursor: pointer;
}
.error { color: #cf222e; font-size: 13px; margin: 0 0 12px; }

.detail-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin: 16px 0 20px;
}
.detail-header h1 { margin: 0 0 4px; font-size: 22px; }
.detail-header-actions { display: flex; gap: 8px; flex-shrink: 0; }
.rename-form { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.rename-input {
  flex: 1 1 280px;
  min-width: 0;
  font: inherit;
  font-size: 20px;
  padding: 4px 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
}
.rename-input:focus { outline: none; border-color: var(--accent); }
.rename-form .refresh { font-size: 13px; font-weight: normal; }
.detail-header .tile-id { font-size: 13px; }
.detail-stats { display: flex; gap: 24px; margin-bottom: 20px; font-size: 13px; color: var(--text-muted); }
.detail-stats strong { color: var(--text); font-size: 16px; display: block; }

table.events {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
table.events th, table.events td {
  text-align: left;
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
}
table.events th { color: var(--text-muted); font-weight: 500; }

.refresh {
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--card-bg);
  color: var(--text);
  cursor: pointer;
  font-size: 13px;
  text-decoration: none;
  display: inline-block;
  white-space: nowrap;
}
.refresh:hover { border-color: var(--accent); }
.refresh.danger:hover { border-color: #cf222e; color: #cf222e; }

.section-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin: 28px 0 12px;
}

/* Sequential blue ramp (light->dark = low->high magnitude on a light surface;
   reversed on dark, since the near-zero step must recede toward *that* surface). */
:root {
  --cal-level-1: #86b6ef;
  --cal-level-2: #3987e5;
  --cal-level-3: #1c5cab;
  --cal-level-4: #0d366b;
}
@media (prefers-color-scheme: dark) {
  :root {
    --cal-level-1: #184f95;
    --cal-level-2: #2a78d6;
    --cal-level-3: #6da7ec;
    --cal-level-4: #b7d3f6;
  }
}

.cal-section {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card-bg);
  padding: 16px;
}

.cal-scroll { overflow-x: auto; }

.cal-months {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 11px;
  column-gap: 3px;
  height: 14px;
  margin-left: 24px;
  margin-bottom: 4px;
}
.cal-month-label {
  grid-row: 1;
  font-size: 11px;
  color: var(--text-muted);
  white-space: nowrap;
}

.cal-body { display: flex; gap: 4px; }

.cal-weekday-labels {
  display: grid;
  grid-template-rows: repeat(7, 11px);
  row-gap: 3px;
  width: 20px;
  flex-shrink: 0;
}
.cal-weekday-label {
  font-size: 9px;
  color: var(--text-muted);
  line-height: 11px;
}

.cal-grid {
  display: grid;
  grid-template-rows: repeat(7, 11px);
  grid-auto-flow: column;
  grid-auto-columns: 11px;
  gap: 3px;
}

.cal-cell {
  width: 11px;
  height: 11px;
  border-radius: 2px;
  background: var(--border);
  cursor: pointer;
  outline-offset: 1px;
}
.cal-cell:hover, .cal-cell:focus-visible { outline: 1px solid var(--accent); }
.cal-cell.selected { outline: 2px solid var(--accent); }
.cal-level-1 { background: var(--cal-level-1); }
.cal-level-2 { background: var(--cal-level-2); }
.cal-level-3 { background: var(--cal-level-3); }
.cal-level-4 { background: var(--cal-level-4); }

.cal-legend {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-top: 10px;
  font-size: 11px;
  color: var(--text-muted);
}
.cal-legend .cal-cell { cursor: default; }

.day-detail {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}
.day-detail h3 { font-size: 14px; margin: 0 0 10px; }
.day-detail-loading { color: var(--text-muted); font-size: 13px; }

.page-title { font-size: 20px; margin: 16px 0 20px; }

.user-form {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card-bg);
  margin-bottom: 12px;
}
.user-form input[type="text"],
.user-form input[type="password"],
.user-form input[type="number"],
.user-form select {
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
}
.user-form input[type="number"] { width: 90px; }
.hint { color: var(--text-muted); font-size: 13px; margin: 0 0 12px; }
.checkbox-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--text-muted);
}
.user-form button {
  padding: 8px 14px;
  border: none;
  border-radius: 6px;
  background: var(--accent);
  color: white;
  font-size: 14px;
  cursor: pointer;
}