/* =============================================
   SimplaDocs × Coda Course — Shared Stylesheet
   Brand: brand.html (simpladocs)
   ============================================= */

/* Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Rethink+Sans:ital,wght@0,400;0,500;0,600;0,700;0,800;1,400&family=Instrument+Serif:ital@1&display=swap');

/* =============================================
   DESIGN TOKENS
   ============================================= */
:root {
  --navy:        #0d2d52;
  --navy-deep:   #071829;
  --royal:       #2e57ca;
  --cyan:        #3de3ff;
  --sky:         #199bde;
  --lavender:    #889beb;
  --medium:      #2d84ef;
  --ice:         #e4f0fb;
  --bg:          #f1f3f6;
  --white:       #ffffff;
  --muted:       rgba(13,45,82,0.55);
  --border:      rgba(13,45,82,0.09);
  --grad:        linear-gradient(90deg, #2e57ca, #3de3ff);
  --grad-hover:  linear-gradient(90deg, #003566, #2e7cf7);

  --beginner:    #2e57ca;
  --intermediate:#199bde;
  --advanced:    #7c3aed;
  --superadv:    #be185d;
}

/* =============================================
   RESET & BASE
   ============================================= */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'Rethink Sans', sans-serif;
  background: var(--bg);
  color: var(--navy);
  line-height: 1.6;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: var(--royal); }
code, pre {
  font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', Consolas, monospace;
}

/* Grid background pattern */
.brand-grid {
  background-color: var(--bg);
  background-image:
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='80' height='80'%3E%3Crect width='80' height='80' fill='none' stroke='rgba(13,45,82,0.055)' stroke-width='0.5'/%3E%3Cline x1='0' y1='0' x2='80' y2='80' stroke='rgba(13,45,82,0.04)' stroke-width='0.5'/%3E%3Cline x1='80' y1='0' x2='0' y2='80' stroke='rgba(13,45,82,0.04)' stroke-width='0.5'/%3E%3Cline x1='40' y1='0' x2='40' y2='80' stroke='rgba(13,45,82,0.03)' stroke-width='0.5'/%3E%3Cline x1='0' y1='40' x2='80' y2='40' stroke='rgba(13,45,82,0.03)' stroke-width='0.5'/%3E%3C/svg%3E");
}

/* =============================================
   NAV
   ============================================= */
.course-nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(241,243,246,0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1100px; margin: 0 auto;
  padding: 12px 24px;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.nav-brand {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--navy);
  font-weight: 700; font-size: 15px; white-space: nowrap;
}
.nav-brand-badge {
  background: var(--grad); color: white;
  font-size: 10px; font-weight: 700; letter-spacing: 0.08em;
  text-transform: uppercase; padding: 3px 9px; border-radius: 100px;
}
.nav-lesson-info {
  font-size: 13px; color: var(--muted); flex: 1;
  text-align: center; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.nav-lesson-info strong { color: var(--navy); }
.nav-actions {
  display: flex; align-items: center; gap: 8px; flex-shrink: 0;
}
.nav-btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 16px; border-radius: 100px;
  font-size: 13px; font-weight: 600; text-decoration: none;
  transition: all 0.2s; white-space: nowrap;
}
.nav-btn-outline {
  background: var(--white); color: var(--navy);
  border: 1px solid var(--border);
}
.nav-btn-outline:hover { background: var(--navy); color: white; border-color: var(--navy); }
.nav-btn-primary {
  background: var(--grad); color: white; border: none;
}
.nav-btn-primary:hover { background: var(--grad-hover); transform: translateY(-1px); }

/* Progress bar */
.lesson-progress {
  height: 3px; background: var(--border);
}
.lesson-progress-fill {
  height: 100%; background: var(--grad); transition: width 0.3s;
}

/* =============================================
   LESSON HERO
   ============================================= */
.lesson-hero {
  padding: 72px 24px 56px;
  text-align: center; position: relative; overflow: hidden;
}
.hero-level-badge {
  display: inline-flex; align-items: center; gap: 8px;
  border-radius: 100px; padding: 6px 16px;
  font-size: 11px; font-weight: 700; letter-spacing: 0.1em;
  text-transform: uppercase; margin-bottom: 24px;
}
.badge-beginner     { background: rgba(46,87,202,0.1);  color: var(--beginner);     border: 1px solid rgba(46,87,202,0.2); }
.badge-intermediate { background: rgba(25,155,222,0.1); color: var(--intermediate); border: 1px solid rgba(25,155,222,0.2); }
.badge-advanced     { background: rgba(124,58,237,0.1); color: var(--advanced);     border: 1px solid rgba(124,58,237,0.2); }
.badge-super        { background: rgba(190,24,93,0.1);  color: var(--superadv);     border: 1px solid rgba(190,24,93,0.2); }

.lesson-hero h1 {
  font-size: clamp(32px, 6vw, 64px);
  font-weight: 700; line-height: 1.05;
  letter-spacing: -0.025em; margin-bottom: 16px;
}
.lesson-hero h1 em {
  font-family: 'Instrument Serif', serif;
  font-style: italic; font-weight: 400;
}
.hero-sub {
  font-size: 18px; color: var(--muted);
  max-width: 580px; margin: 0 auto 32px; line-height: 1.65;
}
.hero-meta {
  display: inline-flex; align-items: center; gap: 20px;
  background: var(--white); border: 1px solid var(--border);
  border-radius: 100px; padding: 10px 24px;
  font-size: 13px; color: var(--muted); font-weight: 500;
}
.hero-meta span { display: flex; align-items: center; gap: 6px; }
.hero-meta .sep { width: 1px; height: 14px; background: var(--border); }

/* =============================================
   LESSON BODY
   ============================================= */
.lesson-body {
  max-width: 860px; margin: 0 auto; padding: 0 24px 80px;
}

/* Sections */
.lesson-section {
  margin-bottom: 64px;
}
.lesson-section:first-child { margin-top: 0; }

.section-eyebrow {
  font-size: 11px; font-weight: 700; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--royal);
  margin-bottom: 12px; display: block;
}
.lesson-section h2 {
  font-size: clamp(24px, 3.5vw, 36px);
  font-weight: 700; line-height: 1.15;
  letter-spacing: -0.02em; margin-bottom: 20px;
}
.lesson-section h2 em {
  font-family: 'Instrument Serif', serif;
  font-style: italic; font-weight: 400;
}
.lesson-section h3 {
  font-size: 20px; font-weight: 700;
  margin: 32px 0 12px; letter-spacing: -0.01em;
}
.lesson-section p {
  font-size: 17px; line-height: 1.72; color: var(--navy);
  margin-bottom: 20px;
}
.lesson-section ul, .lesson-section ol {
  margin: 0 0 20px 24px;
}
.lesson-section li {
  font-size: 17px; line-height: 1.72; margin-bottom: 8px;
}

/* =============================================
   CARDS
   ============================================= */
.card {
  background: var(--white); border-radius: 20px;
  border: 1px solid var(--border); padding: 32px;
  margin-bottom: 20px;
}
.card-sm {
  background: var(--white); border-radius: 16px;
  border: 1px solid var(--border); padding: 20px 24px;
}

/* Info/callout box */
.callout {
  border-radius: 16px; padding: 20px 24px;
  margin-bottom: 24px; font-size: 15px; line-height: 1.65;
}
.callout-blue {
  background: rgba(46,87,202,0.07);
  border-left: 3px solid var(--royal);
  border-radius: 0 16px 16px 0;
}
.callout-cyan {
  background: rgba(61,227,255,0.08);
  border-left: 3px solid var(--cyan);
  border-radius: 0 16px 16px 0;
}
.callout-purple {
  background: rgba(124,58,237,0.07);
  border-left: 3px solid var(--advanced);
  border-radius: 0 16px 16px 0;
}
.callout strong { font-weight: 700; display: block; margin-bottom: 4px; }

/* =============================================
   CODE BLOCKS
   ============================================= */
.code-block {
  background: var(--navy-deep);
  border-radius: 16px; padding: 24px 28px;
  margin-bottom: 24px; overflow-x: auto; position: relative;
}
.code-block pre {
  font-size: 14px; line-height: 1.7;
  color: #e4f0fb;
}
.code-label {
  font-size: 11px; font-weight: 700; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--cyan);
  margin-bottom: 12px; display: block;
}
.code-inline {
  background: rgba(13,45,82,0.08);
  border: 1px solid var(--border);
  border-radius: 6px; padding: 2px 8px;
  font-size: 13px; font-family: monospace;
  color: var(--royal); white-space: nowrap;
}

/* Syntax highlighting */
.tok-fn    { color: #3de3ff; }
.tok-str   { color: #a8f0a8; }
.tok-num   { color: #ffb86c; }
.tok-kw    { color: #889beb; }
.tok-com   { color: rgba(228,240,251,0.4); font-style: italic; }
.tok-ref   { color: #f8c8ff; }

/* =============================================
   CODA UI MOCKUPS
   ============================================= */
.coda-mockup {
  background: var(--white); border-radius: 20px;
  border: 1px solid var(--border);
  overflow: hidden; margin-bottom: 24px;
  box-shadow: 0 4px 24px rgba(13,45,82,0.08);
}
.coda-mockup-bar {
  background: #f7f7f8; border-bottom: 1px solid #e8e8ea;
  padding: 10px 16px; display: flex; align-items: center; gap: 8px;
}
.coda-traffic {
  width: 10px; height: 10px; border-radius: 50%;
  display: inline-block;
}
.coda-traffic.red   { background: #ff5f56; }
.coda-traffic.amber { background: #ffbd2e; }
.coda-traffic.green { background: #27c93f; }
.coda-mock-title {
  font-size: 12px; color: #666; margin-left: 8px; flex: 1; text-align: center;
}
.coda-mockup-body {
  padding: 24px;
}

/* Table mockup */
.mock-table {
  width: 100%; border-collapse: collapse; font-size: 14px;
}
.mock-table th {
  background: #f7f7f8; border-bottom: 2px solid #e8e8ea;
  padding: 8px 12px; text-align: left;
  font-size: 12px; font-weight: 700; color: #555; letter-spacing: 0.04em;
  white-space: nowrap;
}
.mock-table td {
  padding: 9px 12px; border-bottom: 1px solid #f0f0f1;
  vertical-align: middle;
}
.mock-table tr:last-child td { border-bottom: none; }
.mock-table tr:hover td { background: #fafafa; }

/* Column type badges */
.col-type {
  display: inline-flex; align-items: center; gap: 4px;
  font-size: 10px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.06em; padding: 2px 7px; border-radius: 4px;
  vertical-align: middle; margin-left: 4px;
}
.col-text    { background: #f0f0f1; color: #555; }
.col-num     { background: rgba(46,87,202,0.1); color: var(--royal); }
.col-date    { background: rgba(25,155,222,0.12); color: var(--sky); }
.col-select  { background: rgba(124,58,237,0.1); color: var(--advanced); }
.col-check   { background: rgba(25,135,84,0.1); color: #198754; }
.col-rel     { background: rgba(190,24,93,0.1); color: var(--superadv); }
.col-btn     { background: rgba(61,227,255,0.15); color: #0e7490; }
.col-ai      { background: linear-gradient(90deg, rgba(46,87,202,0.1), rgba(61,227,255,0.1)); color: var(--royal); }

/* Select pill */
.select-pill {
  display: inline-flex; align-items: center;
  border-radius: 100px; padding: 2px 10px;
  font-size: 12px; font-weight: 600;
}
.pill-todo       { background: rgba(13,45,82,0.08); color: var(--navy); }
.pill-progress   { background: rgba(46,87,202,0.12); color: var(--royal); }
.pill-done       { background: rgba(25,135,84,0.12); color: #198754; }
.pill-blocked    { background: rgba(220,53,69,0.12); color: #dc3545; }
.pill-high       { background: rgba(190,24,93,0.12); color: var(--superadv); }
.pill-medium     { background: rgba(25,155,222,0.12); color: var(--sky); }
.pill-low        { background: rgba(13,45,82,0.06); color: var(--muted); }

/* =============================================
   FORMULA EXPLAINER
   ============================================= */
.formula-anatomy {
  background: var(--navy-deep); border-radius: 16px;
  padding: 28px 32px; margin-bottom: 24px; overflow-x: auto;
}
.formula-line {
  font-size: 18px; font-family: monospace; color: var(--ice);
  line-height: 1.5; white-space: nowrap; margin-bottom: 20px;
}
.formula-annotations {
  display: flex; flex-wrap: wrap; gap: 12px; margin-top: 8px;
}
.formula-ann {
  background: rgba(255,255,255,0.06); border-radius: 10px;
  padding: 8px 12px; font-size: 13px; line-height: 1.4;
  border-left: 3px solid;
}
.ann-fn   { border-color: #3de3ff; }
.ann-ref  { border-color: #889beb; }
.ann-val  { border-color: #a8f0a8; }
.ann-op   { border-color: #ffb86c; }
.ann-label { font-size: 10px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.08em; color: rgba(228,240,251,0.5); display: block; margin-bottom: 2px; }
.ann-text  { color: var(--ice); }

/* =============================================
   TWO-COLUMN GRIDS
   ============================================= */
.two-col {
  display: grid; grid-template-columns: 1fr 1fr; gap: 20px;
  margin-bottom: 24px;
}
.three-col {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px;
  margin-bottom: 24px;
}

/* Concept card */
.concept-card {
  background: var(--white); border-radius: 20px;
  border: 1px solid var(--border); padding: 28px;
}
.concept-card-icon {
  width: 44px; height: 44px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; margin-bottom: 16px;
}
.concept-card h4 {
  font-size: 16px; font-weight: 700; margin-bottom: 8px;
}
.concept-card p {
  font-size: 14px; color: var(--muted); line-height: 1.6; margin: 0;
}

/* =============================================
   INTERACTIVE ELEMENTS — Fill in the Blank
   ============================================= */
.fitb-widget {
  background: var(--white); border-radius: 20px;
  border: 1px solid var(--border); padding: 36px;
  margin-bottom: 24px;
}
.fitb-header {
  display: flex; align-items: center; gap: 12px; margin-bottom: 24px;
}
.fitb-header h3 {
  font-size: 18px; font-weight: 700; margin: 0;
}
.fitb-badge {
  background: rgba(46,87,202,0.1); color: var(--royal);
  border: 1px solid rgba(46,87,202,0.2);
  font-size: 11px; font-weight: 700; letter-spacing: 0.08em;
  text-transform: uppercase; padding: 4px 12px; border-radius: 100px;
}
.fitb-progress {
  font-size: 13px; color: var(--muted); margin-left: auto;
}

.fitb-question {
  margin-bottom: 32px; padding-bottom: 32px;
  border-bottom: 1px solid var(--border);
}
.fitb-question:last-of-type { border-bottom: none; margin-bottom: 16px; padding-bottom: 0; }
.fitb-q-num {
  font-size: 11px; font-weight: 700; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--muted); margin-bottom: 10px;
}
.fitb-prompt {
  font-size: 16px; line-height: 1.6; margin-bottom: 16px;
  background: var(--bg); border-radius: 12px; padding: 16px 20px;
  font-family: monospace;
}
.fitb-blank {
  display: inline-block;
  border-bottom: 2px solid var(--royal);
  min-width: 80px; padding: 0 4px;
  color: var(--royal); font-weight: 700;
}
.fitb-input-row {
  display: flex; align-items: center; gap: 10px;
}
.fitb-input {
  flex: 1; border: 2px solid var(--border); border-radius: 12px;
  padding: 10px 16px; font-size: 15px; font-family: monospace;
  outline: none; transition: border-color 0.2s;
  background: var(--white); color: var(--navy);
}
.fitb-input:focus { border-color: var(--royal); }
.fitb-input.correct { border-color: #198754; background: rgba(25,135,84,0.05); }
.fitb-input.wrong   { border-color: #dc3545; background: rgba(220,53,69,0.05); }
.fitb-check-btn {
  padding: 10px 20px; border-radius: 12px;
  background: var(--grad); color: white;
  border: none; cursor: pointer; font-size: 14px; font-weight: 600;
  transition: all 0.2s; white-space: nowrap;
}
.fitb-check-btn:hover { background: var(--grad-hover); transform: translateY(-1px); }
.fitb-feedback {
  margin-top: 10px; font-size: 14px; border-radius: 10px;
  padding: 10px 14px; display: none;
}
.fitb-feedback.correct { background: rgba(25,135,84,0.1); color: #198754; display: block; }
.fitb-feedback.wrong   { background: rgba(220,53,69,0.08); color: #dc3545; display: block; }

.fitb-score-bar {
  background: var(--bg); border-radius: 12px; padding: 16px 20px;
  display: flex; align-items: center; justify-content: space-between;
  margin-top: 20px; display: none;
}
.fitb-score-bar.show { display: flex; }
.fitb-score-num { font-size: 24px; font-weight: 800; color: var(--navy); }
.fitb-score-label { font-size: 13px; color: var(--muted); }
.fitb-retry {
  padding: 8px 18px; border-radius: 100px;
  border: 1.5px solid var(--border); background: var(--white);
  color: var(--navy); cursor: pointer; font-size: 13px; font-weight: 600;
  transition: all 0.2s;
}
.fitb-retry:hover { background: var(--navy); color: white; border-color: var(--navy); }

/* =============================================
   INTERACTIVE ELEMENTS — Quiz
   ============================================= */
.quiz-widget {
  background: var(--white); border-radius: 20px;
  border: 1px solid var(--border); padding: 36px;
  margin-bottom: 24px;
}
.quiz-header {
  display: flex; align-items: center; gap: 12px; margin-bottom: 28px;
}
.quiz-badge {
  background: rgba(124,58,237,0.1); color: var(--advanced);
  border: 1px solid rgba(124,58,237,0.2);
  font-size: 11px; font-weight: 700; letter-spacing: 0.08em;
  text-transform: uppercase; padding: 4px 12px; border-radius: 100px;
}
.quiz-q {
  margin-bottom: 28px; padding-bottom: 28px;
  border-bottom: 1px solid var(--border);
}
.quiz-q:last-of-type { border-bottom: none; padding-bottom: 0; }
.quiz-q-num {
  font-size: 11px; font-weight: 700; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--muted); margin-bottom: 8px;
}
.quiz-q-text {
  font-size: 16px; font-weight: 600; line-height: 1.55; margin-bottom: 16px;
}
.quiz-options {
  display: flex; flex-direction: column; gap: 8px;
}
.quiz-option {
  padding: 12px 16px; border-radius: 12px;
  border: 1.5px solid var(--border); cursor: pointer;
  font-size: 15px; transition: all 0.15s; background: var(--white);
  text-align: left; width: 100%;
}
.quiz-option:hover { border-color: var(--royal); background: rgba(46,87,202,0.04); }
.quiz-option.selected { border-color: var(--royal); background: rgba(46,87,202,0.08); }
.quiz-option.correct  { border-color: #198754; background: rgba(25,135,84,0.08); color: #198754; font-weight: 600; }
.quiz-option.wrong    { border-color: #dc3545; background: rgba(220,53,69,0.06); color: #dc3545; }
.quiz-option.reveal-correct { border-color: #198754; background: rgba(25,135,84,0.05); color: #198754; }
.quiz-explain {
  margin-top: 12px; padding: 12px 16px; border-radius: 10px;
  font-size: 14px; line-height: 1.55; display: none;
}
.quiz-explain.show { display: block; }
.quiz-explain.correct { background: rgba(25,135,84,0.08); color: #198754; }
.quiz-explain.wrong   { background: rgba(220,53,69,0.06); color: #dc3545; }
.quiz-submit {
  margin-top: 24px; width: 100%;
  padding: 14px; border-radius: 14px;
  background: var(--grad); color: white;
  border: none; cursor: pointer; font-size: 16px; font-weight: 700;
  transition: all 0.2s;
}
.quiz-submit:hover { background: var(--grad-hover); transform: translateY(-1px); }
.quiz-result {
  margin-top: 20px; padding: 20px 24px; border-radius: 16px;
  background: var(--bg); display: none;
}
.quiz-result.show { display: block; }
.quiz-result-score { font-size: 28px; font-weight: 800; }
.quiz-result-msg { font-size: 15px; color: var(--muted); margin-top: 4px; }

/* =============================================
   LESSON NAVIGATION
   ============================================= */
.lesson-nav {
  display: grid; grid-template-columns: 1fr 1fr; gap: 16px;
  max-width: 860px; margin: 0 auto 64px; padding: 0 24px;
}
.lesson-nav-btn {
  background: var(--white); border-radius: 20px;
  border: 1px solid var(--border); padding: 20px 24px;
  text-decoration: none; color: var(--navy);
  display: flex; flex-direction: column; gap: 4px;
  transition: all 0.2s;
}
.lesson-nav-btn:hover { border-color: var(--royal); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(13,45,82,0.08); }
.lesson-nav-btn.next { text-align: right; }
.lesson-nav-dir { font-size: 11px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); }
.lesson-nav-title { font-size: 15px; font-weight: 700; }
.lesson-nav-num { font-size: 13px; color: var(--muted); }

/* =============================================
   COURSE INDEX
   ============================================= */
.course-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}
.lesson-card {
  background: var(--white); border-radius: 20px;
  border: 1px solid var(--border); padding: 28px;
  text-decoration: none; color: var(--navy);
  display: flex; flex-direction: column; gap: 12px;
  transition: all 0.2s;
}
.lesson-card:hover { border-color: var(--royal); transform: translateY(-3px); box-shadow: 0 12px 32px rgba(13,45,82,0.1); }
.lesson-card-num {
  font-size: 11px; font-weight: 700; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--muted);
}
.lesson-card-title { font-size: 17px; font-weight: 700; line-height: 1.3; }
.lesson-card-desc { font-size: 14px; color: var(--muted); line-height: 1.55; flex: 1; }
.lesson-card-footer {
  display: flex; align-items: center; justify-content: space-between;
  margin-top: 4px;
}
.lesson-card-time { font-size: 12px; color: var(--muted); }
.lesson-card-arrow {
  width: 32px; height: 32px; border-radius: 50%;
  background: var(--bg); display: flex; align-items: center; justify-content: center;
  transition: all 0.2s;
}
.lesson-card:hover .lesson-card-arrow { background: var(--royal); }
.lesson-card:hover .lesson-card-arrow svg path { stroke: white; }

/* Level section headers */
.level-header {
  margin: 56px 0 24px;
  display: flex; align-items: center; gap: 16px;
}
.level-header-line {
  flex: 1; height: 1px; background: var(--border);
}
.level-badge-lg {
  font-size: 12px; font-weight: 700; letter-spacing: 0.1em;
  text-transform: uppercase; padding: 6px 16px; border-radius: 100px;
  white-space: nowrap;
}

/* =============================================
   FOOTER
   ============================================= */
.course-footer {
  background: var(--navy-deep); padding: 48px 24px 36px;
  color: rgba(255,255,255,0.4); text-align: center; margin-top: 0;
}
.course-footer p { font-size: 14px; line-height: 1.6; }
.course-footer a { color: rgba(255,255,255,0.4); text-decoration: none; }
.course-footer a:hover { color: white; }

/* =============================================
   SCROLLSTORY LAYOUT
   ============================================= */

/* TOC pills below hero */
.story-toc {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 10px; padding: 36px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  position: sticky; top: 53px; z-index: 90;
  backdrop-filter: blur(10px);
  background: rgba(241,243,246,0.95);
}
.story-toc a {
  padding: 8px 18px; border-radius: 100px;
  background: var(--white); border: 1px solid var(--border);
  color: var(--navy); font-size: 13px; font-weight: 500;
  text-decoration: none; transition: all 0.2s; white-space: nowrap;
}
.story-toc a:hover { background: var(--navy); color: white; border-color: var(--navy); }
.story-toc a.toc-active { background: var(--royal); color: white; border-color: var(--royal); }

/* Full-width sections */
.story-section {
  padding: 96px 24px;
}
.story-section + .story-section { border-top: 1px solid var(--border); }
.story-section:nth-of-type(even) { background: var(--white); }

/* Container */
.story-container {
  max-width: 1100px; margin: 0 auto;
}

/* Section header */
.story-header { margin-bottom: 56px; }
.story-num {
  font-size: 11px; font-weight: 700; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--royal);
  margin-bottom: 10px; display: block;
}
.story-title {
  font-size: clamp(32px, 4vw, 52px);
  font-weight: 600; line-height: 1.08; letter-spacing: -0.02em;
  margin-bottom: 0;
}
.story-title em {
  font-family: 'Instrument Serif', serif;
  font-style: italic; font-weight: 400;
}
.story-sub {
  font-size: 17px; color: var(--muted);
  max-width: 680px; line-height: 1.65; margin-top: 14px;
}

/* Content styles inside story sections (mirrors .lesson-section rules) */
.story-section p {
  font-size: 17px; line-height: 1.72; color: var(--navy);
  margin-bottom: 20px;
}
.story-section ul, .story-section ol {
  margin: 0 0 20px 24px;
}
.story-section li {
  font-size: 17px; line-height: 1.72; margin-bottom: 8px;
}
.story-section h3 {
  font-size: 20px; font-weight: 700;
  margin: 32px 0 12px; letter-spacing: -0.01em;
}

/* Widen lesson-nav to match story container */
.lesson-nav { max-width: 1100px; }

/* =============================================
   RESPONSIVE
   ============================================= */
@media (max-width: 900px) {
  .course-grid { grid-template-columns: repeat(2, 1fr); }
  .two-col { grid-template-columns: 1fr; }
  .three-col { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .course-grid { grid-template-columns: 1fr; }
  .three-col { grid-template-columns: 1fr; }
  .lesson-nav { grid-template-columns: 1fr; }
  .nav-lesson-info { display: none; }
  .hero-meta { flex-direction: column; gap: 8px; border-radius: 16px; }
  .hero-meta .sep { display: none; }
  .lesson-hero { padding: 48px 24px 40px; }
  .story-toc { top: 48px; padding: 20px 16px; gap: 8px; }
  .story-section { padding: 64px 20px; }
}