/* pyPod CodeClub — shared lesson stylesheet */

:root {
  --brand:        #89B4FA;
  --brand-dark:   #5a8fd4;
  --purple:       #CBA6F7;
  --green:        #A6E3A1;
  --yellow:       #F9E2AF;
  --red:          #F38BA8;
  --bg:           #FFFFFF;
  --surface:      #F4F4F8;
  --border:       #D9D9E8;
  --text:         #1E1E2E;
  --muted:        #6C7086;
  --code-bg:      #1E1E2E;
  --code-text:    #CDD6F4;
  --code-comment: #6C7086;
  --code-kw:      #CBA6F7;
  --code-str:     #A6E3A1;
  --code-num:     #FAB387;
  --code-fn:      #89B4FA;
  --nav-h:        56px;
}

/* ── Reset ─────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 17px; scroll-behavior: smooth; }

body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  padding-bottom: 4rem;
}

/* ── Top navigation bar ─────────────────────────────────────────── */
.topbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--text);
  color: #fff;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  padding: 0 1.5rem;
  gap: 1rem;
}

.topbar .logo {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--brand);
  text-decoration: none;
  margin-right: auto;
}

.topbar a {
  color: #cdd6f4;
  text-decoration: none;
  font-size: 0.9rem;
  padding: 0.3rem 0.7rem;
  border-radius: 6px;
  transition: background 0.15s;
}

.topbar a:hover      { background: rgba(255,255,255,0.1); }
.topbar a.active     { background: var(--brand); color: #1e1e2e; font-weight: 600; }

/* ── Page header ────────────────────────────────────────────────── */
.lesson-header {
  background: linear-gradient(135deg, var(--text) 0%, #313244 100%);
  color: #fff;
  padding: 3rem 2rem 2.5rem;
}

.lesson-header .session-tag {
  display: inline-block;
  background: var(--brand);
  color: var(--text);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 0.2rem 0.7rem;
  border-radius: 20px;
  margin-bottom: 0.8rem;
}

.lesson-header h1 { font-size: 2rem; font-weight: 700; margin-bottom: 0.5rem; }
.lesson-header .subtitle { color: #BAC2DE; font-size: 1.05rem; }

/* ── Main content area ──────────────────────────────────────────── */
.content {
  max-width: 860px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

/* ── Info panels ────────────────────────────────────────────────── */
.panel {
  border-left: 4px solid var(--brand);
  background: var(--surface);
  border-radius: 0 8px 8px 0;
  padding: 1rem 1.25rem;
  margin-bottom: 1.5rem;
}

.panel.objectives { border-color: var(--green); }
.panel.concepts   { border-color: var(--purple); }
.panel.challenge  { border-color: var(--yellow); background: #fffdf4; }
.panel.warning    { border-color: var(--red);    background: #fff4f4; }
.panel.tip        { border-color: var(--brand);  background: #f0f5ff; }

.panel-title {
  font-weight: 700;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
  color: var(--muted);
}

.panel.objectives .panel-title { color: #3d8a3a; }
.panel.concepts   .panel-title { color: #7c5fa8; }
.panel.challenge  .panel-title { color: #9a7a1a; }
.panel.warning    .panel-title { color: #b83030; }
.panel.tip        .panel-title { color: var(--brand-dark); }

.panel ul, .panel ol { padding-left: 1.3rem; }
.panel li { margin-bottom: 0.25rem; }

/* ── Section headings ───────────────────────────────────────────── */
h2 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2.2rem 0 0.75rem;
  padding-bottom: 0.35rem;
  border-bottom: 2px solid var(--border);
  color: var(--text);
}

h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 1.5rem 0 0.5rem;
  color: var(--text);
}

p { margin-bottom: 0.9rem; }

/* ── Numbered steps ─────────────────────────────────────────────── */
.steps { counter-reset: step; list-style: none; padding: 0; }

.steps > li {
  counter-increment: step;
  position: relative;
  padding: 1rem 1rem 1rem 3.5rem;
  margin-bottom: 1rem;
  background: var(--surface);
  border-radius: 8px;
  border: 1px solid var(--border);
}

.steps > li::before {
  content: counter(step);
  position: absolute;
  left: 0.85rem;
  top: 1rem;
  width: 1.7rem;
  height: 1.7rem;
  background: var(--brand);
  color: var(--text);
  font-weight: 700;
  font-size: 0.85rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ── Code blocks ────────────────────────────────────────────────── */
pre {
  background: var(--code-bg);
  color: var(--code-text);
  border-radius: 8px;
  padding: 1.1rem 1.25rem;
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.6;
  margin: 0.75rem 0 1rem;
  tab-size: 4;
}

code {
  font-family: 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
}

p code, li code {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.1em 0.35em;
  font-size: 0.88em;
  color: #6c7086;
}

/* Syntax colouring — applied via <span> inside <pre><code> */
.kw  { color: var(--code-kw);      font-weight: 600; }   /* keyword */
.fn  { color: var(--code-fn);                        }   /* function/method */
.str { color: var(--code-str);                       }   /* string */
.num { color: var(--code-num);                       }   /* number/constant */
.cm  { color: var(--code-comment); font-style: italic; } /* comment */

/* ── Filename label above a code block ──────────────────────────── */
.filename {
  display: inline-block;
  background: var(--code-bg);
  color: var(--muted);
  font-family: monospace;
  font-size: 0.78rem;
  padding: 0.25rem 0.75rem;
  border-radius: 6px 6px 0 0;
  margin-bottom: -2px;
}

/* ── Inline callout ─────────────────────────────────────────────── */
.callout {
  display: flex;
  gap: 0.75rem;
  background: var(--surface);
  border-radius: 8px;
  padding: 0.9rem 1rem;
  margin: 1rem 0;
  border: 1px solid var(--border);
  align-items: flex-start;
}

.callout .icon { font-size: 1.4rem; line-height: 1; }
.callout p     { margin: 0; font-size: 0.95rem; }

/* ── Bottom lesson navigation ───────────────────────────────────── */
.lesson-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 2px solid var(--border);
  gap: 1rem;
}

.lesson-nav a {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.6rem 1.2rem;
  border-radius: 8px;
  background: var(--surface);
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--border);
  transition: background 0.15s, border-color 0.15s;
}

.lesson-nav a:hover         { background: var(--brand); border-color: var(--brand); color: var(--text); }
.lesson-nav a.disabled      { opacity: 0.35; pointer-events: none; }
.lesson-nav .lesson-counter { color: var(--muted); font-size: 0.9rem; }

/* ── Responsive ─────────────────────────────────────────────────── */
@media (max-width: 600px) {
  .lesson-header h1 { font-size: 1.5rem; }
  .topbar a:not(.logo) { display: none; }
  .topbar a.active     { display: inline-flex; }
  pre { font-size: 0.8rem; }
}