/* ============================================================
   base.css  — codemathbike v2 unified layout (refined)
   Version 2.0 layout – established Oct 2025
   ============================================================ */

/* ─── Root tokens ──────────────────────────────────────────── */
:root {
  /* layout sizing */
  --sidebar-w: 200px;         /* was 260px */
  --right-rail-w: 220px;      /* was 300px */
  --header-h: 90px;
  --page-max: 1480px;         /* a tad wider canvas for the center column */
  --gap: 1.5rem;              /* was 2rem */

  /* surfaces */
  --bg: #f7f9fb;
  --surface: #ffffff;
  --surface-alt: #fcfcfc;
  --border: #e5e5e5;
  --shadow: 0 4px 18px rgba(0, 0, 0, 0.05);

  /* text */
  --text: #0f172a;
  --muted: #475569;

  /* accent defaults */
  --accent: #6a1b9a;
  --accent-hover: #4a148c;

  /* typography */
  --font-body: "Segoe UI", "Segoe UI Variable", system-ui, -apple-system, Roboto, sans-serif;
  --font-light: 300;
  --font-regular: 400;
  --radius: 12px;

  /* new: type scale tokens (smaller overall) */
  --base-font: 14px;                /* was 16px */
  --h1: clamp(22px, 2.2vw, 32px);
  --h2: clamp(18px, 1.9vw, 26px);
  --h3: clamp(16px, 1.6vw, 22px);

  --top-offset: calc(var(--header-h) + 1rem);

  /* ─── Code block colors ─────────────────────────────────── */
  --code-bg: #0f172a;     /* dark slate */
  --code-text: #e5e7eb;   /* light gray text */
  --code-border: #1f2937; /* subtle border */
  --code-inline: #f1f5f9; /* chip bg for inline code */
}

  
  /* ─── Accents per course ───────────────────────────────────── */
  body.theme-ict8 { --accent: #2e7d32; --accent-hover: #1b5e20; }
  body.theme-ict9 { --accent: #1565c0; --accent-hover: #0d47a1; }
  body.theme-dc1011 { --accent: #b8860b; --accent-hover: #b45309; }
  body.ict8   { --accent: #2e7d32; --accent-hover: #1b5e20; }
  body.ict9   { --accent: #1565c0; --accent-hover: #0d47a1; }
  body.dc1011 { --accent: #f59e0b; --accent-hover: #b45309; }

  /* ─── Resets ───────────────────────────────────────────────── */
  *,
  *::before,
  *::after { box-sizing: border-box; }
  
  html { scroll-behavior: smooth; }
  
  /* Resets keep as-is above */
  body {
    margin: 0;
    font: var(--base-font)/1.6 var(--font-body);  /* use the new token */
    color: var(--text);
    background: var(--bg);
    padding-top: 0;
  }

  /* ─── Typography (new, compact & responsive) ───────────────── */
h1 { font-size: var(--h1); line-height: 1.2; font-weight: 500; margin: 0 0 .5rem; }
h2 { font-size: var(--h2); line-height: 1.25; font-weight: 500; margin: 0 0 .5rem; }
h3 { font-size: var(--h3); line-height: 1.3; font-weight: 500; margin: 0 0 .4rem; }


  /* make rails a touch smaller so content stands out */
  #sidebar, #right-rail { font-size: 0.95rem; }
  #content { font-size: 1rem; }  /* readable body size in main column */

  
  img, video, iframe { max-width: 100%; height: auto; border-radius: var(--radius); }
  a { color: var(--accent); text-decoration: none; }
  a:hover { color: var(--accent-hover); text-decoration: underline; }
  
  a { color: var(--accent); }
  #site-header, #site-footer { border-top: 4px solid var(--accent); }
  #sidebar a.active { color: var(--accent); }

  /* ─── Header ───────────────────────────────────────────────── */
  #site-header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: var(--header-h);
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    box-shadow: 0 2px 6px rgba(0,0,0,.05);
    display: flex; align-items: center; justify-content: space-between;
    padding: 0 2rem;
    z-index: 1000;
  }
  #site-header h1 {
    font-weight: var(--font-light);
    font-size: 1.6rem;
    color: var(--accent);
    margin: 0;
  }
  
  /* ─── Layout grid ──────────────────────────────────────────── */
  .page-wrap {
    display: grid;
    grid-template-columns: var(--sidebar-w) minmax(0, 1fr) var(--right-rail-w);
    gap: var(--gap);
    max-width: var(--page-max);
    margin: 0 auto;
    padding: 0 var(--gap) var(--gap);
    align-items: start; /* already present later, safe to keep here */
  }

  @media (max-width: 1100px) {
    /* show left + content; hide right rail below */
  .page-wrap { grid-template-columns: var(--sidebar-w) 1fr; }
  #right-rail { display: none; }
  }

  @media (max-width: 768px) {
    .page-wrap { grid-template-columns: 1fr; padding: 1rem; }
  #sidebar { position: static; }
  }

  
  /* — Sidebar (tree-line card, deterministic) — */
  #sidebar {
    background: var(--surface-alt);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.2rem 1rem;
    position: sticky;
    top: var(--top-offset);
    align-self: start;
    box-shadow: var(--shadow);
  }
  
  #sidebar h2 {
    margin-top: 0;
    color: var(--accent);
    font-weight: var(--font-light);
  }
  
  /* units */
  #sidebar .unit { margin-bottom: .75rem; }
  
  /* unit header (no chevron) */
  #sidebar .unit .unit-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: .55rem .65rem;
    margin: .25rem 0;
    border-radius: 8px;
    cursor: pointer;
    user-select: none;
    position: relative;
  }
  #sidebar .unit .unit-link:hover { background: rgba(0,0,0,.04); }
  #sidebar .unit .unit-link:focus { outline: 2px solid var(--accent); outline-offset: 2px; }
  
  /* lessons container — single vertical guide line */
  #sidebar .unit .nav {
    display: none;                 /* default: collapsed */
    margin-left: .75rem;
    padding-left: .75rem;
    border-left: 2px solid rgba(0,0,0,.12);
    list-style: none;
  }
  #sidebar .unit.is-open .nav {    /* only the open unit shows */
    display: block;
    border-left-color: var(--accent); /* optional accent on open unit */
  }

  #sidebar .unit .nav li {       /* ⬅ add this whole rule */
    list-style: none;
    margin: 0;
    padding: 0;
  }
  
  
  /* lesson links (no horizontal connectors) */
  #sidebar .nav a {
    display: block;
    padding: .45rem .6rem;
    color: var(--text);
  }
  #sidebar .nav a:hover {
    color: var(--accent);
    background: rgba(0,0,0,.04);
  }
  #sidebar .nav a.active {
    font-weight: 600;
    color: var(--accent);
    background: transparent;
  }
  
  
  /* ─── Main content area ────────────────────────────────────── */

  #content {
  min-width: 0;
  margin-top: var(--top-offset);              /* aligns with sticky rails */
  }

  /* absolutely no gap before the first thing in #content */
  #content > :first-child { margin-top: 0 !important; }

  /* consistent spacing between siblings in #content */
  #content > * + * { margin-top: 1.5rem; }

  /* cards have no intrinsic margins (spacing handled above) */
  .card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 1.5rem;
    /* no margin here */
  }

  #content ul li,
  #content ol li {
  margin-bottom: 0.6em;
}

  
  /* ─── Right rail ───────────────────────────────────────────── */
  #right-rail {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1rem;
    position: sticky;
    top: var(--top-offset);
    align-self: start;
    box-shadow: var(--shadow);
  }
  #right-rail h2 {
    font-weight: var(--font-light);
    color: var(--accent);
    margin-top: 0;
  }
  #right-rail .card {
    border: none;
    box-shadow: none;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border);
  }
  #right-rail .card:last-child { border-bottom: none; }
  
  /* ─── Footer ───────────────────────────────────────────────── */
  #site-footer {
    margin-top: 3rem;
    padding: 1rem 2rem;
    border-top: 1px solid var(--border);
    text-align: center;
    color: var(--muted);
    font-size: 0.9rem;
  }
  
  /* ─── Utilities ────────────────────────────────────────────── */
  .text-center { text-align: center; }
  .muted { color: var(--muted); }
  .btn {
    display: inline-block;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: var(--radius);
    padding: 0.6rem 1.2rem;
    font-weight: var(--font-regular);
    cursor: pointer;
    transition: background .2s ease;
  }
  .btn:hover { background: var(--accent-hover); }
  
  @media print {
    body { background: #fff; }
    #sidebar, #right-rail, #site-header { display: none; }
    .page-wrap { grid-template-columns: 1fr; }
  }
  /* ===== Align columns & remove extra gap in main ===== */

  /* Make all three columns start at the same height under the fixed header */
  .page-wrap { align-items: start; }

  /* Main column clears the header by the same offset as the sticky rails */
  #content { margin-top: var(--top-offset); }

  /* Keep regular spacing between cards, but not before the first one */
  #content .card { margin-top: 1rem; }
  #content .card:first-child { margin-top: 0; }

  /* (If your first section isn't using .card, cover that too) */
  #content > section:first-child { margin-top: 0; }

  /* ─── List spacing ─────────────────────────────────────────── */
  ul li,
  ol li {
    margin-bottom: 0.5em;   /* adds vertical space between items */
  }

  /* remove the last item’s extra gap */
  ul li:last-child,
  ol li:last-child {
    margin-bottom: 0;
  }


  /* ─── Table Formating ───────────────────────────────────── */
  /* Schedule table styling */
  table.schedule {
    width: 100%;
    border-collapse: separate;     /* keep rounded card edges */
    border-spacing: 0;
  }

  table.schedule th,
  table.schedule td {
    padding: .6rem .8rem;
    vertical-align: top;
  }

  /* Bold the first column (time) nicely */
  table.schedule th {
    font-weight: 600;
    white-space: nowrap;
  }

  /* Draw a stronger rule at the start of each block */
  table.schedule tr.block-start > * {
    border-top: 2px solid rgba(0,0,0,.15);     /* use your var(--border) if you prefer */
  }

  /* Softer rule before “Break”/“Lunch” rows (and a light tint) */
  table.schedule tr.break-row > * {
    border-top: 1px solid rgba(0,0,0,.1);
    background: rgba(0,0,0,.02);
    font-style: italic;
  }

  /* Remove the very top rule so the card’s top radius stays clean */
  table.schedule tbody tr:first-child > * {
    border-top: none;
  }

  /* Print-friendly: make rules darker on paper */
  @media print {
    table.schedule tr.block-start > * { border-top-color: #000; }
    table.schedule tr.break-row  > * { border-top-color: #666; }
  }

  
/* ============================================================
   Enhanced Table Styles for Rubrics / Schedules (v2 compatible)
   ============================================================ */
    .table-wrap {
      overflow: auto;
      margin: 0 0 1rem 0;
    }

    table.schedule-table {
      width: 100%;
      border-collapse: separate;
      border-spacing: 0;
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      font-size: 0.95rem;
      box-shadow: var(--shadow);
    }

    /* Header */
    table.schedule-table thead th {
      position: sticky;
      top: 0;
      background: var(--surface-alt);
      color: var(--text);
      font-weight: 600;
      text-align: left;
      padding: 0.75rem 1rem;
      border-bottom: 1px solid var(--border);
    }

    /* Body cells */
    table.schedule-table td {
      padding: 0.75rem 1rem;
      vertical-align: top;
      border-bottom: 1px solid var(--border);
      color: var(--text);
      line-height: 1.45;
    }

    /* Zebra rows for readability */
    table.schedule-table tbody tr:nth-child(even) {
      background: #f9fafc;
    }

    /* Rounded corners (if table in a card) */
    table.schedule-table thead th:first-child { border-top-left-radius: var(--radius); }
    table.schedule-table thead th:last-child  { border-top-right-radius: var(--radius); }
    table.schedule-table tbody tr:last-child td:first-child { border-bottom-left-radius: var(--radius); }
    table.schedule-table tbody tr:last-child td:last-child  { border-bottom-right-radius: var(--radius); }

    /* Text wrapping for long rubric text */
    table.schedule-table th,
    table.schedule-table td {
      word-break: normal;
      overflow-wrap: anywhere;
    }

    /* Slight hover highlight (optional) */
    table.schedule-table tbody tr:hover {
      background: rgba(0,0,0,0.015);
    }

    /* Compact variant inside cards */
    .card .table-wrap { margin-bottom: 0.75rem; }

    @media (max-width: 768px) {
      table.schedule-table {
        font-size: 0.9rem;
      }
      table.schedule-table th,
      table.schedule-table td {
        padding: 0.6rem 0.75rem;
      }
    }

/* ─── Code Blocks ──────────────────────────────────────────── */
  /* Inline code chips (within paragraphs) */
code {
  background: var(--code-inline);
  color: #111827;
  padding: 0 .4em;
  border-radius: 6px;
  font-family: "Cascadia Mono","Consolas",ui-monospace,monospace;
  font-size: 0.95rem;
}

/* Multi-line code blocks like in this chat */
pre {
  background: var(--code-bg);
  color: var(--code-text);
  border: 1px solid var(--code-border);
  border-radius: 10px;
  padding: 1rem 1.25rem;
  overflow: auto;
  box-shadow: var(--shadow);
  -webkit-overflow-scrolling: touch;
}
pre code {
  background: transparent;   /* don’t double-tint inside pre */
  color: inherit;
  font-family: "Cascadia Mono","Consolas",ui-monospace,monospace;
  font-size: 0.95rem;
  line-height: 1.6;
  tab-size: 2;
  white-space: pre;          /* preserve formatting */
}
/* Breadcrumbs sit under the site title, left-aligned */
#breadcrumbs {
  display: block;
  margin-top: .25rem;
  font-size: .9rem;
  line-height: 1.3;
  text-align: left;        /* prevent inheriting centered header styles */
}

#breadcrumbs a {
  color: inherit;
  text-decoration: none;
}

#breadcrumbs a:hover {
  text-decoration: underline;
}

.crumb-sep {
  margin: 0 .4rem;
  opacity: .6;
}

#site-footer { border-top: 1px solid var(--border-200, #e5e7eb); margin-top: 2rem; padding: 1rem 0; }
#site-footer .footer-brand { margin: 0; font-size: .95rem; }
.sr-only { position: absolute; width:1px; height:1px; padding:0; margin:-1px; overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; border:0; }