/* Canadian Ham Radio Basic Qualification Study Guide - Shared Styles */

/* ===== DARK THEME (default) ===== */
:root {
  --bg-primary: #1a1a2e;
  --bg-secondary: #16213e;
  --bg-card: #1e2a4a;
  --bg-highlight: #0f3460;
  --text-primary: #e8e8e8;
  --text-secondary: #b0b0b0;
  --text-heading: #ffffff;
  --accent-blue: #4fc3f7;
  --accent-green: #81c784;
  --accent-orange: #ffb74d;
  --accent-red: #ef5350;
  --accent-purple: #b39ddb;
  --accent-cyan: #4dd0e1;
  --border-color: #2a3a5e;
  --key-fact-bg: #1b3a2a;
  --key-fact-border: #4caf50;
  --warning-bg: #3a2a1b;
  --warning-border: #ff9800;
  --tip-bg: #1b2a3a;
  --tip-border: #2196f3;
  --rule-bg: #2a1b3a;
  --rule-border: #9c27b0;
  --analogy-bg: #1b2a2a;
  --mnemonic-bg: #2a2a1b;
  --mnemonic-border: #ffd54f;
  --diagram-bg: #0d1117;
  --toc-bg: rgba(22, 33, 62, 0.97);
  --toc-active: rgba(79, 195, 247, 0.15);
  --toc-hover: rgba(79, 195, 247, 0.08);
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
  --shadow-sm: 0 1px 4px rgba(0,0,0,0.3);
  --scrollbar-thumb: #2a3a5e;
  --scrollbar-track: transparent;
  --flash-bg: #162040;
  --flash-border: #2a4a7a;
  --flash-answer-bg: #1a3a2a;
  --flash-answer-border: #2e7d32;
  --qc-bg: #1a2535;
  --details-bg: #141e33;
  --step-hidden-bg: #1a2040;
}

/* ===== LIGHT THEME ===== */
@media (prefers-color-scheme: light) {
  :root {
    --bg-primary: #f5f6fa;
    --bg-secondary: #e8ecf4;
    --bg-card: #ffffff;
    --bg-highlight: #e3edf7;
    --text-primary: #2c3e50;
    --text-secondary: #5a6a7a;
    --text-heading: #1a1a2e;
    --accent-blue: #1565c0;
    --accent-green: #2e7d32;
    --accent-orange: #e65100;
    --accent-red: #c62828;
    --accent-purple: #6a1b9a;
    --accent-cyan: #00838f;
    --border-color: #cdd5e0;
    --key-fact-bg: #e8f5e9;
    --key-fact-border: #4caf50;
    --warning-bg: #fff3e0;
    --warning-border: #ff9800;
    --tip-bg: #e3f2fd;
    --tip-border: #2196f3;
    --rule-bg: #f3e5f5;
    --rule-border: #9c27b0;
    --analogy-bg: #e0f7fa;
    --mnemonic-bg: #fffde7;
    --mnemonic-border: #f9a825;
    --diagram-bg: #f0f4f8;
    --toc-bg: rgba(245, 246, 250, 0.97);
    --toc-active: rgba(21, 101, 192, 0.12);
    --toc-hover: rgba(21, 101, 192, 0.06);
    --shadow: 0 4px 24px rgba(0,0,0,0.1);
    --shadow-sm: 0 1px 4px rgba(0,0,0,0.08);
    --scrollbar-thumb: #b0bec5;
    --scrollbar-track: transparent;
    --flash-bg: #f0f4ff;
    --flash-border: #b0c4e8;
    --flash-answer-bg: #e8f5e9;
    --flash-answer-border: #a5d6a7;
    --qc-bg: #eef2f7;
    --details-bg: #f8fafc;
    --step-hidden-bg: #f0f4f8;
  }
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

@media (min-width: 1280px) {
  body { margin-left: 300px; margin-right: auto; }
}

/* ===== TYPOGRAPHY ===== */
h1 {
  color: var(--accent-blue);
  font-size: 2rem;
  margin-bottom: 0.5rem;
  border-bottom: 3px solid var(--accent-blue);
  padding-bottom: 0.5rem;
}
h1 .subtitle {
  display: block;
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: normal;
  margin-top: 0.3rem;
}
h2 {
  color: var(--accent-cyan);
  font-size: 1.5rem;
  margin-top: 3rem;
  margin-bottom: 1rem;
  padding-bottom: 0.3rem;
  border-bottom: 2px solid var(--border-color);
  scroll-margin-top: 1rem;
}
h3 {
  color: var(--accent-green);
  font-size: 1.2rem;
  margin-top: 2rem;
  margin-bottom: 0.7rem;
}
h4 {
  color: var(--accent-orange);
  font-size: 1rem;
  margin-top: 1.2rem;
  margin-bottom: 0.5rem;
}
p { margin-bottom: 1rem; }
a { color: var(--accent-blue); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ===== CALLOUT BOXES (use sparingly - only for genuinely surprising/critical facts) ===== */
.key-fact, .warning, .tip, .rule, .analogy, .mnemonic {
  padding: 1rem 1.2rem;
  margin: 1.2rem 0;
  border-radius: 8px;
  border-left: 4px solid;
}
.key-fact { background: var(--key-fact-bg); border-color: var(--key-fact-border); }
.key-fact::before { content: "KEY FACT"; display: block; font-size: 0.7rem; font-weight: bold; color: var(--accent-green); margin-bottom: 0.3rem; letter-spacing: 1px; }
.warning { background: var(--warning-bg); border-color: var(--warning-border); }
.warning::before { content: "IMPORTANT"; display: block; font-size: 0.7rem; font-weight: bold; color: var(--accent-orange); margin-bottom: 0.3rem; letter-spacing: 1px; }
.tip { background: var(--tip-bg); border-color: var(--tip-border); }
.tip::before { content: "EXAM TIP"; display: block; font-size: 0.7rem; font-weight: bold; color: var(--accent-blue); margin-bottom: 0.3rem; letter-spacing: 1px; }
.rule { background: var(--rule-bg); border-color: var(--rule-border); }
.rule::before { content: "REGULATION"; display: block; font-size: 0.7rem; font-weight: bold; color: var(--accent-purple); margin-bottom: 0.3rem; letter-spacing: 1px; }
.analogy { background: var(--analogy-bg); border-color: var(--accent-cyan); }
.analogy::before { content: "ANALOGY"; display: block; font-size: 0.7rem; font-weight: bold; color: var(--accent-cyan); margin-bottom: 0.3rem; letter-spacing: 1px; }
.mnemonic { background: var(--mnemonic-bg); border-color: var(--mnemonic-border); }
.mnemonic::before { content: "MEMORY AID"; display: block; font-size: 0.7rem; font-weight: bold; color: var(--mnemonic-border); margin-bottom: 0.3rem; letter-spacing: 1px; }

/* ===== TABLES ===== */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.2rem 0;
  font-size: 0.95rem;
}
thead th {
  background: var(--bg-highlight);
  color: var(--accent-blue);
  padding: 0.7rem 1rem;
  text-align: left;
  border-bottom: 2px solid var(--accent-blue);
}
tbody td {
  padding: 0.6rem 1rem;
  border-bottom: 1px solid var(--border-color);
}
tbody tr:hover { background: var(--toc-hover); }

/* ===== ASCII DIAGRAMS (JetBrains Mono) ===== */
.diagram {
  background: var(--diagram-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.2rem;
  margin: 1.2rem 0;
  overflow-x: auto;
}
.diagram pre {
  font-family: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'Consolas', monospace;
  font-size: 0.82rem;
  line-height: 1.45;
  color: var(--accent-green);
  margin: 0;
  white-space: pre;
}
.diagram .caption {
  color: var(--text-secondary);
  font-size: 0.8rem;
  text-align: center;
  margin-top: 0.5rem;
  font-style: italic;
}

/* ===== INLINE CODE (JetBrains Mono) ===== */
code {
  font-family: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'Consolas', monospace;
  background: var(--bg-highlight);
  color: var(--accent-orange);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-size: 0.85em;
}

/* ===== LISTS ===== */
ul, ol { margin: 0.8rem 0 1rem 1.5rem; }
li { margin-bottom: 0.4rem; }
li strong { color: var(--accent-blue); }

/* ===== COLLAPSIBLE DETAILS ===== */
details {
  background: var(--details-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  margin: 1rem 0;
  overflow: hidden;
}
details[open] {
  border-color: var(--accent-blue);
}
details summary {
  padding: 0.8rem 1.2rem;
  cursor: pointer;
  font-weight: 600;
  color: var(--accent-blue);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  user-select: none;
  list-style: none;
  transition: background 0.2s;
}
details summary::-webkit-details-marker { display: none; }
details summary::before {
  content: "▶";
  font-size: 0.7rem;
  transition: transform 0.2s;
  flex-shrink: 0;
}
details[open] summary::before {
  transform: rotate(90deg);
}
details summary:hover {
  background: var(--toc-hover);
}
details .details-content,
details > :not(summary) {
  padding: 0 1.2rem 1rem;
}
details .details-content > :first-child {
  margin-top: 0;
}

/* Deep dive variant */
details.deep-dive summary { color: var(--accent-purple); }
details.deep-dive { border-left: 3px solid var(--accent-purple); }

/* Worked example variant */
details.worked-example summary { color: var(--accent-orange); }
details.worked-example { border-left: 3px solid var(--accent-orange); }

/* Practice questions variant */
details.practice-questions summary {
  color: var(--accent-green);
  font-size: 1rem;
}
details.practice-questions {
  border-left: 3px solid var(--accent-green);
  background: var(--bg-secondary);
}

/* ===== FLASH CARDS (Self-Test) ===== */
.flash-card {
  background: var(--flash-bg);
  border: 1px solid var(--flash-border);
  border-radius: 8px;
  padding: 1rem 1.2rem;
  margin: 0.8rem 0;
  transition: border-color 0.3s;
}
.flash-card.revealed {
  border-color: var(--accent-green);
}
.flash-card .flash-question {
  font-weight: 500;
  margin-bottom: 0.5rem;
}
.flash-card .flash-options {
  margin: 0.5rem 0;
  padding-left: 0;
  list-style: none;
}
.flash-card .flash-options li {
  padding: 0.25rem 0.5rem;
  margin: 0.2rem 0;
  border-radius: 4px;
  font-size: 0.9rem;
}
.flash-reveal-btn {
  display: block;
  margin: 0.8rem auto 0.3rem;
  padding: 0.4rem 1.2rem;
  border: 1px solid var(--accent-blue);
  background: transparent;
  color: var(--accent-blue);
  border-radius: 20px;
  cursor: pointer;
  font-size: 0.85rem;
  transition: all 0.2s;
}
.flash-reveal-btn:hover {
  background: var(--accent-blue);
  color: #fff;
}
.flash-answer {
  background: var(--flash-answer-bg);
  border: 1px solid var(--flash-answer-border);
  border-radius: 6px;
  padding: 0.8rem 1rem;
  margin-top: 0.5rem;
}
.flash-answer .correct {
  color: var(--accent-green);
  font-weight: 700;
}

/* ===== QUICK CHECK ===== */
.quick-check {
  background: var(--qc-bg);
  border: 1px dashed var(--border-color);
  border-radius: 8px;
  padding: 0.6rem 1rem;
  margin: 1.5rem 0;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}
.quick-check::before {
  content: "?";
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent-blue);
  color: #fff;
  font-weight: bold;
  font-size: 0.75rem;
  flex-shrink: 0;
}
.qc-question { cursor: pointer; }
.qc-question:hover { color: var(--accent-blue); }
.qc-answer {
  font-weight: 600;
  color: var(--accent-green);
}

/* ===== STEP-BY-STEP WORKED EXAMPLES ===== */
.step-reveal { margin: 1rem 0; }
.step {
  padding: 0.6rem 1rem;
  margin: 0.3rem 0;
  border-left: 3px solid var(--border-color);
  transition: opacity 0.3s;
}
.step-hidden {
  display: none;
}
.step-btn {
  display: block;
  margin: 0.3rem 0;
  padding: 0.35rem 1rem;
  border: 1px dashed var(--accent-orange);
  background: transparent;
  color: var(--accent-orange);
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.8rem;
  transition: all 0.2s;
}
.step-btn:hover {
  background: var(--accent-orange);
  color: #fff;
  border-style: solid;
}

/* ===== STUDY MODE TOGGLE ===== */
.study-mode-btn {
  display: block;
  margin: 1rem 0;
  padding: 0.5rem 1.2rem;
  border: 2px solid var(--accent-purple);
  background: transparent;
  color: var(--accent-purple);
  border-radius: 24px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 600;
  transition: all 0.2s;
}
.study-mode-btn.active {
  background: var(--accent-purple);
  color: #fff;
}
.study-mode-btn:hover { opacity: 0.85; }

/* ===== SECTION INTRO ===== */
.section-intro {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-secondary);
  border-left: 3px solid var(--accent-cyan);
  padding-left: 1rem;
  margin: 1rem 0 1.5rem;
}

/* ===== CONCEPT CARD (lighter than key-fact, for regular concepts) ===== */
.concept {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1rem 1.2rem;
  margin: 1rem 0;
}
.concept strong { color: var(--accent-blue); }

/* ===== SCENARIO BOX ===== */
.scenario {
  background: var(--bg-highlight);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1rem 1.2rem;
  margin: 1rem 0;
  font-style: italic;
}
.scenario::before {
  content: "SCENARIO";
  display: block;
  font-size: 0.7rem;
  font-weight: bold;
  font-style: normal;
  color: var(--accent-orange);
  margin-bottom: 0.3rem;
  letter-spacing: 1px;
}

/* ===== SECTION DIVIDER ===== */
.section-divider {
  border: none;
  border-top: 1px solid var(--border-color);
  margin: 2.5rem 0;
}

/* ===== STATIC NAV-BOX ===== */
.nav-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1rem 1.5rem;
  margin: 1.5rem 0;
}
.nav-box h3 { color: var(--text-heading); margin-top: 0; font-size: 1rem; }
.nav-box ul { list-style: none; margin-left: 0; columns: 2; }
.nav-box li { margin-bottom: 0.3rem; }
.nav-box a { color: var(--accent-cyan); }

/* ===== SUMMARY / REFERENCE CARDS ===== */
.summary-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.2rem;
  margin: 1rem 0;
}
.summary-card h4 { margin-top: 0; color: var(--accent-blue); }

.formula {
  background: var(--bg-highlight);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1rem 1.5rem;
  margin: 1rem 0;
  text-align: center;
  font-size: 1.1rem;
}

.covers {
  display: inline-block;
  background: var(--bg-highlight);
  color: var(--text-secondary);
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  border-radius: 12px;
  margin-left: 0.5rem;
  vertical-align: middle;
}

/* ===== FLOATING TOC ===== */
.floating-toc {
  position: fixed; top: 0; left: 0;
  width: 260px; height: 100vh;
  background: var(--toc-bg);
  border-right: 1px solid var(--border-color);
  box-shadow: var(--shadow);
  overflow-y: auto;
  padding: 1rem 0;
  z-index: 1000;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  scrollbar-width: thin;
  scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track);
}
.floating-toc::-webkit-scrollbar { width: 5px; }
.floating-toc::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 3px; }
.floating-toc.open { transform: translateX(0); }
@media (min-width: 1280px) { .floating-toc { transform: translateX(0); } }
.floating-toc .toc-header { padding: 0.5rem 1rem 0.8rem; border-bottom: 1px solid var(--border-color); margin-bottom: 0.5rem; }
.floating-toc .toc-header a { font-size: 0.7rem; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px; display: flex; align-items: center; gap: 0.4rem; }
.floating-toc .toc-header a:hover { color: var(--accent-blue); text-decoration: none; }
.floating-toc .toc-title { font-size: 0.85rem; font-weight: 700; color: var(--accent-blue); margin-top: 0.4rem; line-height: 1.3; }
.floating-toc ul { list-style: none; margin: 0; padding: 0; }
.floating-toc li a { display: block; padding: 0.35rem 1rem; font-size: 0.8rem; color: var(--text-secondary); border-left: 3px solid transparent; transition: all 0.2s; line-height: 1.4; }
.floating-toc li a:hover { background: var(--toc-hover); color: var(--text-primary); text-decoration: none; }
.floating-toc li a.active { background: var(--toc-active); color: var(--accent-blue); border-left-color: var(--accent-blue); font-weight: 600; }

.toc-toggle {
  position: fixed; bottom: 1.5rem; left: 1.5rem;
  width: 48px; height: 48px; border-radius: 50%;
  background: var(--accent-blue); color: #fff; border: none;
  cursor: pointer; z-index: 1001;
  display: flex; align-items: center; justify-content: center;
  box-shadow: 0 2px 12px rgba(0,0,0,0.3);
  transition: transform 0.2s; font-size: 1.2rem;
}
.toc-toggle:hover { transform: scale(1.1); }
@media (min-width: 1280px) { .toc-toggle { display: none; } }

.toc-progress { height: 3px; background: var(--border-color); margin: 0 1rem 0.5rem; border-radius: 2px; overflow: hidden; }
.toc-progress-bar { height: 100%; background: var(--accent-blue); width: 0%; transition: width 0.15s ease; border-radius: 2px; }

/* ===== RESPONSIVE ===== */
@media (max-width: 600px) {
  body { padding: 1rem; }
  h1 { font-size: 1.5rem; }
  h2 { margin-top: 2rem; }
  .nav-box ul { columns: 1; }
  table { font-size: 0.85rem; }
  thead th, tbody td { padding: 0.4rem 0.6rem; }
  .flash-card .flash-options { font-size: 0.85rem; }
}

/* ===== LIGHTBOX ===== */
.lightbox {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.85);
  z-index: 2000;
  cursor: zoom-out;
  align-items: center;
  justify-content: center;
  padding: 2rem;
}
.lightbox.lightbox-open {
  display: flex;
}
.lightbox img {
  max-width: 95vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: 8px;
  box-shadow: 0 8px 40px rgba(0,0,0,0.5);
  cursor: default;
}
@media (prefers-color-scheme: light) {
  .lightbox { background: rgba(255,255,255,0.92); }
  .lightbox img { box-shadow: 0 8px 40px rgba(0,0,0,0.15); }
}

/* Diagram container for D2 SVGs */
.diagram-container {
  text-align: center;
  margin: 1.2rem 0;
}
.diagram-container img {
  max-width: 100%;
  max-height: 400px;
  height: auto;
  object-fit: contain;
  cursor: zoom-in;
}
.dark-diagram { display: block; margin: 0 auto; }
.light-diagram { display: none; margin: 0 auto; }
@media (prefers-color-scheme: light) {
  .dark-diagram { display: none; }
  .light-diagram { display: block; }
}

/* KaTeX theme */
.katex { color: var(--text-primary); }
.katex .mord { color: var(--text-primary); }