/* =========================================================================
   Design tokens — quiet, Apple-inspired.
   Neutral surfaces, single blue accent, system font stack, generous space.
   ======================================================================= */

:root {
  /* surfaces */
  --bg: #F5F5F7;
  --panel: #FFFFFF;
  --panel-2: #F5F5F7;
  --panel-3: #EBEBEE;
  --overlay: rgba(0, 0, 0, 0.04);

  /* text */
  --fg: #1D1D1F;
  --fg-soft: #424245;
  --muted: #6E6E73;
  --muted-2: #86868B;

  /* lines */
  --border: #D2D2D7;
  --border-strong: #C6C6CC;

  /* signals */
  --accent: #0071E3;       /* Apple system blue */
  --accent-hover: #0077ED;
  --accent-soft: rgba(0, 113, 227, 0.10);
  --good: #34C759;
  --good-soft: rgba(52, 199, 89, 0.10);
  --bad:  #FF3B30;
  --bad-soft: rgba(255, 59, 48, 0.10);
  --warn: #FF9500;

  /* type — SF Pro on Apple, system-ui elsewhere. --font-serif retained
     for backward compat but resolves to the same system stack. */
  --font-sans:  -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-serif: var(--font-sans);
  --font-mono:  ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  /* radius / shadow */
  --r-sm: 8px;
  --r-md: 12px;
  --r-lg: 18px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.55;
  letter-spacing: -0.003em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

/* role-based hiding: admin-only elements stay out of the DOM for users */
body:not(.is-admin) [data-admin-only] { display: none !important; }

/* -----------------------------------------------------------------------
   Top navigation
   --------------------------------------------------------------------- */
header {
  padding: 0;
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  position: sticky;
  top: 0;
  z-index: 20;
}
.topbar {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 14px 28px;
  max-width: 1280px;
  margin: 0 auto;
  font-size: 14px;
}
.topbar .brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--fg);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.015em;
}
.topbar .brand .dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
}
.topbar nav {
  display: flex;
  gap: 4px;
  margin-left: 8px;
}
.topbar nav a {
  color: var(--muted);
  text-decoration: none;
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 14px;
  transition: color 0.15s, background 0.15s;
}
.topbar nav a:hover { color: var(--fg); background: var(--panel-2); }
.topbar nav a.active { color: var(--fg); background: var(--panel-2); }

.topbar .spacer { flex: 1; }
.topbar .topbar-link {
  color: var(--muted);
  text-decoration: none;
  padding: 6px 10px;
  border-radius: 6px;
}
.topbar .topbar-link:hover { color: var(--fg); background: var(--panel-2); }
.topbar-sep { color: var(--border-strong); margin: 0 2px; }

.user-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 10px 6px 6px;
  border-radius: 999px;
  background: var(--panel);
  border: 1px solid var(--border);
  font-size: 13px;
}
.user-chip .avatar {
  width: 24px; height: 24px;
  border-radius: 50%;
  background: var(--accent);
  color: white;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.4px;
  text-transform: uppercase;
}
.user-chip .role-tag {
  font-size: 10px;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  color: var(--muted);
}
.user-chip .signout {
  background: transparent;
  border: 0;
  color: var(--muted);
  cursor: pointer;
  font: inherit;
  padding: 0 4px 0 4px;
  border-left: 1px solid var(--border);
  margin-left: 4px;
}
.user-chip .signout:hover { color: var(--accent); }

/* -----------------------------------------------------------------------
   Headings
   --------------------------------------------------------------------- */
h1, h2, h3 { font-family: var(--font-sans); font-weight: 600; }
h1 { font-size: 40px; line-height: 1.1;  letter-spacing: -0.022em; margin: 0 0 14px; }
h2 { font-size: 22px; line-height: 1.25; letter-spacing: -0.015em; margin: 0 0 10px; }
h3 { font-size: 17px; letter-spacing: -0.01em; margin: 0 0 8px; }
p  { color: var(--fg-soft); margin: 0 0 12px; }
small, .muted { color: var(--muted); }

/* -----------------------------------------------------------------------
   Layout shells
   --------------------------------------------------------------------- */
main {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
  gap: 20px;
  padding: 28px 28px 56px;
  max-width: 1280px;
  margin: 0 auto;
}

.shell {
  max-width: 1080px;
  margin: 0 auto;
  padding: 32px 28px 80px;
}
.shell-narrow {
  max-width: 720px;
  margin: 0 auto;
  padding: 40px 24px 80px;
}

/* -----------------------------------------------------------------------
   Cards & surfaces
   --------------------------------------------------------------------- */
.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 24px 26px;
  min-width: 0;
  box-shadow: var(--shadow-sm);
}
.card h2 {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
}
.card h2 small { color: var(--muted); font-family: var(--font-sans); font-weight: 400; font-size: 13px; }

.surface {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-sm);
}

/* -----------------------------------------------------------------------
   Pills & chips
   --------------------------------------------------------------------- */
.pill {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 2px 10px;
  font-size: 12px;
  color: var(--muted);
  font-family: var(--font-sans);
  font-weight: 500;
}
.pill.accept { background: var(--good-soft); color: var(--good); border-color: rgba(44,122,77,0.18); }
.pill.reject { background: var(--bad-soft);  color: var(--bad);  border-color: rgba(177,66,66,0.18); }
.pill.skip   { background: var(--panel-2);   color: var(--muted); }
.accent { color: var(--accent); }

.kv { color: var(--muted); font-size: 13px; }
.kv strong { color: var(--fg); font-weight: 600; margin-left: 4px; }

/* -----------------------------------------------------------------------
   Buttons
   --------------------------------------------------------------------- */
button, .btn {
  font: inherit;
  cursor: pointer;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border: 1px solid var(--accent);
  border-radius: 980px;
  padding: 10px 20px;
  font-weight: 500;
  letter-spacing: -0.01em;
  transition: background 0.15s, border-color 0.15s, transform 0.05s;
}
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
.btn-primary:active { transform: translateY(1px); }
.btn-primary:disabled {
  background: var(--panel-3);
  color: var(--muted-2);
  border-color: var(--panel-3);
  cursor: not-allowed;
}

.btn-secondary {
  background: var(--panel);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: 980px;
  padding: 9px 18px;
  font-weight: 500;
  letter-spacing: -0.01em;
  transition: background 0.15s, border-color 0.15s;
}
.btn-secondary:hover { background: var(--panel-2); border-color: var(--border-strong); }
.btn-secondary:disabled {
  color: var(--muted-2);
  border-color: var(--border);
  cursor: not-allowed;
}

.btn-ghost {
  background: transparent;
  color: var(--accent);
  border: 0;
  padding: 8px 14px;
  border-radius: var(--r-sm);
  font-weight: 500;
}
.btn-ghost:hover { background: var(--accent-soft); }

.btn-big { padding: 13px 26px; font-size: 15px; }

/* -----------------------------------------------------------------------
   Forms
   --------------------------------------------------------------------- */
.field { margin-bottom: 16px; }
.field label {
  display: block;
  margin-bottom: 6px;
  color: var(--muted);
  font-size: 13px;
  letter-spacing: 0.01em;
}
.field input, .field select {
  width: 100%;
  background: var(--panel);
  border: 1px solid var(--border-strong);
  border-radius: var(--r-sm);
  padding: 11px 14px;
  font: inherit;
  color: var(--fg);
  transition: border-color 0.15s, box-shadow 0.15s;
}
.field input:focus, .field select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

/* -----------------------------------------------------------------------
   Tables
   --------------------------------------------------------------------- */
table { width: 100%; border-collapse: collapse; font-size: 13px; }
th, td { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--border); }
th { color: var(--muted); font-weight: 500; font-size: 11px; text-transform: uppercase; letter-spacing: 0.06em; }
td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }

/* -----------------------------------------------------------------------
   Hero block (used by study + landing)
   --------------------------------------------------------------------- */
.hero {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  padding: 28px 30px;
  margin-bottom: 20px;
  box-shadow: var(--shadow-sm);
}
.hero h1 { margin: 0 0 8px; font-size: 32px; }
.hero h1 .accent { color: var(--accent); }
.hero p { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.6; max-width: 64ch; }
.hero-meta {
  display: flex;
  gap: 18px;
  margin-top: 16px;
  flex-wrap: wrap;
  font-size: 13px;
  color: var(--muted);
}
.hero-meta strong { color: var(--fg); margin-left: 4px; font-weight: 600; }
.hero-steps {
  display: flex;
  gap: 10px;
  margin-top: 20px;
  flex-wrap: wrap;
}
.hero-step {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 5px 14px 5px 5px;
  font-size: 13px;
  color: var(--fg-soft);
}
.hero-step .num {
  background: var(--accent);
  color: white;
  font-weight: 600;
  width: 22px; height: 22px;
  border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 11px;
}

/* -----------------------------------------------------------------------
   Generic ordered list (preserves the dashboard list rendering)
   --------------------------------------------------------------------- */
ol { padding-left: 20px; margin: 0; }
ol li { margin-bottom: 10px; }

/* -----------------------------------------------------------------------
   Image grid (study mode + qa)
   --------------------------------------------------------------------- */
.mcq-images, .qa-images {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 10px 0;
}
.mcq-images img, .qa-images img {
  max-width: 280px;
  max-height: 220px;
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  background: var(--panel-2);
  object-fit: contain;
}

/* -----------------------------------------------------------------------
   Footer
   --------------------------------------------------------------------- */
footer {
  padding: 18px 28px 28px;
  color: var(--muted);
  font-size: 12px;
  border-top: 1px solid var(--border);
  max-width: 1280px;
  margin: 0 auto;
}
footer a { color: var(--accent); text-decoration: none; margin-right: 10px; }
footer a:hover { text-decoration: underline; }

/* -----------------------------------------------------------------------
   Helpers
   --------------------------------------------------------------------- */
.hidden { display: none !important; }
.muted-cell { color: var(--muted); }
.mono { font-family: var(--font-mono); font-size: 12px; }

/* -----------------------------------------------------------------------
   Loader / spinner
   --------------------------------------------------------------------- */
.spinner {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 2px solid var(--border-strong);
  border-top-color: var(--accent);
  animation: spin 0.75s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.loading-label { color: var(--muted); font-size: 14px; margin-top: 10px; }

/* -----------------------------------------------------------------------
   Cost-related elements (admin only — hidden when body lacks .is-admin)
   --------------------------------------------------------------------- */
.cost-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-bottom: 12px;
}
.cost-grid .kpi {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  padding: 12px 14px;
}
.cost-grid .kpi .label { color: var(--muted); font-size: 11px; text-transform: uppercase; letter-spacing: 0.06em; }
.cost-grid .kpi .value { font-size: 20px; font-variant-numeric: tabular-nums; font-weight: 600; }

.scope-buttons { display: flex; gap: 6px; margin-top: 10px; }
.scope-buttons button {
  background: var(--panel);
  color: var(--fg);
  border: 1px solid var(--border-strong);
  border-radius: var(--r-sm);
  padding: 6px 12px;
  cursor: pointer;
  font: inherit;
}
.scope-buttons button.active { background: var(--accent); color: #fff; border-color: var(--accent); }

/* mcq card (used by dashboard list) */
.mcq {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  padding: 12px 14px;
}
.mcq .stem { font-weight: 500; margin-bottom: 6px; }
.mcq .opts { display: grid; grid-template-columns: 1fr; gap: 2px; margin-bottom: 6px; }
.mcq .opt { padding-left: 22px; position: relative; color: var(--muted); }
.mcq .opt .letter { position: absolute; left: 0; color: var(--muted); }
.mcq .opt.correct { color: var(--good); }
.mcq .opt.correct .letter { color: var(--good); }
.mcq .meta { color: var(--muted); font-size: 12px; }
.mcq .meta span { margin-right: 10px; }
.mcq .citation { color: var(--accent); font-size: 12px; margin-top: 4px; }

/* rejected items (admin-only context) */
.rejected-item {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-left: 3px solid var(--bad);
  border-radius: var(--r-sm);
  padding: 10px 14px;
}
.rejected-item .reason { color: var(--muted); font-size: 12px; margin-top: 4px; }

/* syllabus tree */
#syllabus-tree details {
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  margin-bottom: 6px;
  padding: 6px 12px;
  background: var(--panel-2);
}
#syllabus-tree summary { cursor: pointer; font-size: 13px; }
#syllabus-tree .muted { color: var(--muted); font-size: 11px; }
#syllabus-tree .syllabus-list { margin: 6px 0 4px; padding-left: 22px; list-style: square; }
#syllabus-tree .syllabus-list a { color: var(--accent); text-decoration: none; }
#syllabus-tree .syllabus-list a:hover { text-decoration: underline; }

/* daemon log */
pre#log-tail {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--r-sm);
  padding: 12px;
  max-height: 320px;
  overflow: auto;
  font-size: 12px;
  white-space: pre-wrap;
  word-break: break-all;
  font-family: var(--font-mono);
}

/* status-strip (legacy class on landing) */
.status-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  color: var(--muted);
  font-size: 14px;
  margin-top: 4px;
}
.status-strip .kv strong { color: var(--fg); margin-left: 4px; }
.status-strip .alive { color: var(--good); }
.status-strip .dead  { color: var(--bad); }