/* ============================================
   Scalp Health Research -- Global Stylesheet
   v2.0 -- Class mismatch fixes + visual upgrade
   ============================================ */

/* ------------------------------------------
   1. CUSTOM PROPERTIES (Design Tokens)
   ------------------------------------------ */
:root {
  /* Colors */
  --color-primary: #C41E3A;
  --color-primary-hover: #A01830;
  --color-bg: #FAF8F5;
  --color-surface: #E8E4DF;
  --color-text: #1A1A1A;
  --color-text-secondary: #4A4A4A;
  --color-muted: #8A8580;
  --color-accent-green: #5A7C65;
  --color-white: #ffffff;
  --color-dark: #1A1A1A;

  /* Typography */
  --font-heading: 'DM Serif Display', Georgia, serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --fs-xs: 0.75rem;
  --fs-sm: 0.85rem;
  --fs-base: 1rem;
  --fs-md: 1.125rem;
  --fs-lg: 1.35rem;
  --fs-xl: 1.75rem;
  --fs-2xl: 2.25rem;
  --fs-3xl: 2.75rem;
  --fs-4xl: 3.25rem;
  --lh-tight: 1.2;
  --lh-base: 1.6;
  --lh-loose: 1.8;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;
  --space-5xl: 8rem;

  /* Borders & Shadows */
  --radius: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --shadow-card: 0 1px 3px rgba(26, 26, 26, 0.04), 0 4px 16px rgba(26, 26, 26, 0.06);
  --shadow-card-hover: 0 2px 8px rgba(26, 26, 26, 0.06), 0 8px 32px rgba(26, 26, 26, 0.1);
  --shadow-nav: 0 1px 4px rgba(26, 26, 26, 0.08);
  --shadow-input-focus: 0 0 0 3px rgba(196, 30, 58, 0.12);

  /* Layout */
  --container-max: 1200px;
  --container-narrow: 720px;
  --nav-height: 64px;

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-base: 0.2s ease;
  --transition-slow: 0.3s ease;
}


/* ------------------------------------------
   2. RESET + BASE TYPOGRAPHY
   ------------------------------------------ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  overflow-x: clip;   /* iOS Safari fix -- MUST NOT be overridden */
  overflow-y: auto;
  scroll-behavior: smooth;
}

body {
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
  width: 100%;
}

body {
  font-family: var(--font-body);
  font-size: var(--fs-base);
  line-height: var(--lh-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-wrap: break-word;
  word-wrap: break-word;
}

img, video, svg {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-base);
}

a:hover {
  color: var(--color-primary-hover);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  line-height: var(--lh-tight);
  color: var(--color-text);
}

h1 { font-size: var(--fs-3xl); }
h2 { font-size: var(--fs-2xl); margin-bottom: var(--space-lg); }
h3 { font-size: var(--fs-xl); }
h4 { font-size: var(--fs-lg); }

/* RED BORDER only inside article body -- NOT global */
.article-body h2 {
  border-bottom: 2px solid var(--color-primary);
  padding-bottom: var(--space-sm);
  margin-bottom: var(--space-lg);
}

p {
  margin-bottom: var(--space-md);
  color: var(--color-text-secondary);
}

ul, ol {
  padding-left: var(--space-lg);
  margin-bottom: var(--space-md);
}

li {
  margin-bottom: var(--space-xs);
}

blockquote {
  border-left: 4px solid var(--color-primary);
  padding: var(--space-md) var(--space-lg);
  margin: var(--space-lg) 0;
  background: var(--color-surface);
  font-style: italic;
  color: var(--color-text-secondary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

strong { color: var(--color-text); }


/* ------------------------------------------
   3. CONTAINER
   ------------------------------------------ */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.container--narrow {
  max-width: var(--container-narrow);
}

/* Article layout (content + sidebar grid) */
.article-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2xl);
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

@media (min-width: 1024px) {
  .article-layout {
    grid-template-columns: 1fr 260px;
  }
}

.article-body {
  min-width: 0; /* prevent grid blowout */
  word-break: break-word;
}

@media (max-width: 768px) {
  .container {
    padding: 0 var(--space-md);
  }
  .article-layout {
    padding: 0 var(--space-md);
    gap: var(--space-lg);
  }
  /* Hide sidebar TOC on mobile */
  .sidebar-toc {
    display: none;
  }
}


/* ------------------------------------------
   4. GLOBAL NAV (.site-nav)
   Supports BOTH BEM (.site-nav__*) and flat (.site-logo, .nav-links, .nav-toggle)
   ------------------------------------------ */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--color-white);
  height: var(--nav-height);
  display: flex;
  align-items: center;
  transition: box-shadow var(--transition-base);
  border-bottom: 1px solid rgba(0, 0, 0, 0.04);
  overflow: visible;
  width: 100%;
}

.site-nav.scrolled {
  box-shadow: var(--shadow-nav);
  border-bottom-color: transparent;
}

.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

/* Logo -- both naming patterns */
.site-nav__logo,
.site-nav .site-logo {
  font-family: var(--font-heading);
  font-size: var(--fs-lg);
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.site-nav__logo:hover,
.site-nav .site-logo:hover {
  color: var(--color-primary);
}

/* Nav links -- both naming patterns */
.site-nav__links,
.site-nav .nav-links {
  display: flex;
  list-style: none;
  gap: var(--space-xl);
  padding: 0;
  margin: 0;
  align-items: center;
}

.site-nav__links a,
.site-nav .nav-links a {
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  transition: color var(--transition-base);
  position: relative;
}

.site-nav__links a:hover,
.site-nav .nav-links a:hover {
  color: var(--color-primary);
}

.site-nav__links a::after,
.site-nav .nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width var(--transition-base);
}

.site-nav__links a:hover::after,
.site-nav .nav-links a:hover::after {
  width: 100%;
}

/* Hamburger -- both naming patterns */
.site-nav__hamburger,
.site-nav .nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
}

.site-nav__hamburger span,
.site-nav .nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  margin: 5px 0;
  transition: transform var(--transition-slow), opacity var(--transition-slow);
}

/* Hamburger animation when open */
.site-nav.nav-open .site-nav__hamburger span:nth-child(1),
.site-nav.nav-open .nav-toggle span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}
.site-nav.nav-open .site-nav__hamburger span:nth-child(2),
.site-nav.nav-open .nav-toggle span:nth-child(2) {
  opacity: 0;
}
.site-nav.nav-open .site-nav__hamburger span:nth-child(3),
.site-nav.nav-open .nav-toggle span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}


/* ------------------------------------------
   5. HERO SECTION
   ------------------------------------------ */
.hero {
  padding: var(--space-5xl) 0 var(--space-4xl);
  text-align: center;
  position: relative;
}

.hero .container {
  max-width: 860px;
}

.hero h1 {
  font-size: var(--fs-4xl);
  margin-bottom: var(--space-lg);
  letter-spacing: -0.02em;
  line-height: 1.15;
}

.hero .subtitle,
.hero .hero-subtitle,
.hero-subtitle {
  font-size: var(--fs-lg);
  color: var(--color-muted);
  line-height: var(--lh-loose);
  max-width: 640px;
  margin: 0 auto var(--space-2xl);
}

.hero p:not(.subtitle) {
  font-size: var(--fs-md);
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto var(--space-2xl);
}

.hero-compact {
  padding: var(--space-3xl) 0 var(--space-2xl);
}

.hero-actions,
.hero-ctas {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
}


/* ------------------------------------------
   6. CTA BUTTONS
   ------------------------------------------ */
.cta-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary);
  color: var(--color-white);
  font-family: var(--font-body);
  font-size: var(--fs-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 0.875rem 2rem;
  border: 2px solid var(--color-primary);
  border-radius: var(--radius);
  cursor: pointer;
  transition: transform var(--transition-base), box-shadow var(--transition-base), background var(--transition-base);
  text-decoration: none;
  line-height: 1;
}

.cta-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(196, 30, 58, 0.3);
  background: var(--color-primary-hover);
  color: var(--color-white);
}

/* Secondary (outline) variant */
.cta-button--secondary {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.cta-button--secondary:hover {
  background: var(--color-primary);
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(196, 30, 58, 0.2);
}

/* Small variant */
.cta-button--sm {
  font-size: var(--fs-xs);
  padding: 0.625rem 1.25rem;
}


/* ------------------------------------------
   7. EMAIL CAPTURE FORMS
   Handles: <form class="email-capture"> with bare <input> and <button class="cta-button">
   Also handles BEM: .email-capture__form, .email-capture__input, .email-capture__button
   ------------------------------------------ */

/* Wrapper section (when email-capture is inside a section/div) */
.email-section {
  padding: var(--space-4xl) 0;
  text-align: center;
}

.email-section h2 {
  margin-bottom: var(--space-sm);
}

.email-section p {
  max-width: 520px;
  margin: 0 auto var(--space-xl);
  color: var(--color-text-secondary);
}

/* The form element itself (flat class: <form class="email-capture">) */
form.email-capture,
.email-capture__form {
  display: flex;
  max-width: 520px;
  margin: 0 auto;
  gap: var(--space-sm);
  align-items: stretch;
}

/* Email input -- bare input inside .email-capture OR BEM .email-capture__input */
form.email-capture input[type="email"],
.email-capture__form input[type="email"],
.email-capture__input {
  flex: 1;
  padding: 0.875rem var(--space-lg);
  border: 1px solid var(--color-surface);
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: var(--fs-base);
  background: var(--color-white);
  color: var(--color-text);
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
  -webkit-appearance: none;
  appearance: none;
}

form.email-capture input[type="email"]:hover,
.email-capture__form input[type="email"]:hover,
.email-capture__input:hover {
  border-color: var(--color-muted);
}

form.email-capture input[type="email"]:focus,
.email-capture__form input[type="email"]:focus,
.email-capture__input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: var(--shadow-input-focus);
}

form.email-capture input[type="email"]::placeholder,
.email-capture__form input[type="email"]::placeholder,
.email-capture__input::placeholder {
  color: var(--color-muted);
}

/* Button inside the form -- uses .cta-button class, just ensure it aligns */
form.email-capture .cta-button,
.email-capture__button {
  flex-shrink: 0;
  white-space: nowrap;
}

/* Mid-page email capture wrapper (used as section container in articles) */
div.email-capture {
  background: var(--color-surface);
  padding: var(--space-2xl);
  border-radius: var(--radius-lg);
  text-align: center;
  margin: var(--space-2xl) 0;
  overflow: hidden;
}

div.email-capture h3 {
  margin-bottom: var(--space-sm);
}

div.email-capture p {
  margin-bottom: var(--space-lg);
  color: var(--color-text-secondary);
}

/* Mid-page email capture (standalone section with bg) */
.email-capture-box {
  background: var(--color-surface);
  padding: var(--space-2xl);
  border-radius: var(--radius-lg);
  text-align: center;
  margin: var(--space-2xl) 0;
}

.email-capture-box h3 {
  margin-bottom: var(--space-sm);
}

.email-capture-box p {
  margin-bottom: var(--space-lg);
  color: var(--color-text-secondary);
}

/* Footer email form -- compact, no background */
.site-footer form.email-capture,
.site-footer .email-capture__form {
  max-width: 100%;
  margin: 0;
}

.site-footer form.email-capture input[type="email"],
.site-footer .email-capture__form input[type="email"],
.site-footer .email-capture__input {
  padding: 0.625rem var(--space-md);
  font-size: var(--fs-sm);
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
  color: var(--color-white);
}

.site-footer form.email-capture input[type="email"]::placeholder,
.site-footer .email-capture__form input[type="email"]::placeholder,
.site-footer .email-capture__input::placeholder {
  color: var(--color-muted);
}

.site-footer form.email-capture input[type="email"]:focus,
.site-footer .email-capture__form input[type="email"]:focus,
.site-footer .email-capture__input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(196, 30, 58, 0.2);
}

.site-footer form.email-capture .cta-button,
.site-footer .email-capture__form .cta-button,
.site-footer .email-capture__button {
  padding: 0.625rem var(--space-lg);
  font-size: var(--fs-xs);
}


/* ------------------------------------------
   8. HOMEPAGE SECTIONS
   ------------------------------------------ */

/* Section spacing pattern */
.homepage-section {
  padding: var(--space-4xl) 0;
}

/* Section with alternate bg */
.section--surface {
  background: var(--color-surface);
}

.section--white {
  background: var(--color-white);
}

.section--dark {
  background: var(--color-dark);
  color: var(--color-surface);
}

.section--dark h2,
.section--dark h3 {
  color: var(--color-white);
}

.section--dark p {
  color: var(--color-muted);
}

/* Section headers */
.section-header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.section-header h2 {
  margin-bottom: var(--space-sm);
}

.section-header p {
  max-width: 560px;
  margin: 0 auto;
  color: var(--color-muted);
  font-size: var(--fs-md);
}

/* Featured articles grid */
.featured-articles {
  padding: var(--space-4xl) 0;
}

.article-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
}

/* Methodology section */
.methodology-section {
  padding: var(--space-4xl) 0;
  background: var(--color-white);
  border-top: 1px solid var(--color-surface);
  border-bottom: 1px solid var(--color-surface);
}

/* About sections */
.about-section {
  padding: var(--space-3xl) 0;
}

.about-section-alt {
  background: var(--color-white);
  border-top: 1px solid var(--color-surface);
  border-bottom: 1px solid var(--color-surface);
}

/* Methodology grid (About page) */
.methodology-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-xl);
  margin-top: var(--space-xl);
}

.methodology-item h3 {
  margin-bottom: var(--space-sm);
}

.methodology-item p {
  font-size: var(--fs-sm);
}

/* Email capture section (homepage) */
.email-capture-section {
  padding: var(--space-4xl) 0;
  text-align: center;
}

.email-capture-section h2 {
  margin-bottom: var(--space-sm);
}

.email-capture-section p {
  max-width: 520px;
  margin: 0 auto var(--space-xl);
  color: var(--color-text-secondary);
}

/* Methodology teaser (homepage) */
.methodology-teaser {
  padding: var(--space-4xl) 0;
  background: var(--color-white);
  border-top: 1px solid var(--color-surface);
  border-bottom: 1px solid var(--color-surface);
}

.methodology-teaser p {
  max-width: 740px;
  font-size: var(--fs-md);
  line-height: var(--lh-loose);
  margin-bottom: var(--space-lg);
}

.methodology-teaser .text-link {
  font-weight: 600;
  font-size: var(--fs-sm);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

/* CTA secondary variant (homepage) */
.cta-secondary {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.cta-secondary:hover {
  background: var(--color-primary);
  color: var(--color-white);
}

/* All articles section */
.all-articles {
  padding: var(--space-4xl) 0;
}

.articles-list .article-list-item {
  display: block;
  padding: var(--space-lg) 0;
  border-bottom: 1px solid var(--color-surface);
  text-decoration: none;
  color: inherit;
  transition: background var(--transition-base);
}

.articles-list .article-list-item:hover {
  background: rgba(232, 228, 223, 0.2);
}

.articles-list .article-list-item h3 {
  font-size: var(--fs-xl);
  margin-bottom: var(--space-sm);
}

.articles-list .article-list-item p {
  font-size: var(--fs-sm);
  color: var(--color-text-secondary);
  margin-bottom: 0;
}

/* All research listing */
.all-research {
  padding: var(--space-4xl) 0;
}


/* ------------------------------------------
   9. ARTICLE CARDS (.article-card)
   ------------------------------------------ */
.article-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
}

.article-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  transition: box-shadow var(--transition-base), transform var(--transition-base);
  display: flex;
  flex-direction: column;
}

.article-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-4px);
}

.article-card a {
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.article-card__image {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.article-card__body {
  padding: var(--space-lg) var(--space-xl) var(--space-xl);
  flex: 1;
  display: flex;
  flex-direction: column;
}

.article-card__category {
  font-size: var(--fs-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
}

.article-card__title {
  font-family: var(--font-heading);
  font-size: var(--fs-lg);
  margin-bottom: var(--space-sm);
  color: var(--color-text);
  line-height: 1.3;
}

.article-card__description {
  font-size: var(--fs-sm);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-lg);
  line-height: var(--lh-base);
  flex: 1;
}

.article-card__link {
  font-size: var(--fs-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-primary);
  transition: color var(--transition-base);
  margin-top: auto;
}

.article-card__link:hover {
  color: var(--color-primary-hover);
}

/* Simple text card (when no image/full card markup) */
.article-card--text {
  padding: var(--space-xl);
}

.article-card--text h3 {
  font-size: var(--fs-lg);
  margin-bottom: var(--space-sm);
}

.article-card--text p {
  font-size: var(--fs-sm);
  margin-bottom: var(--space-md);
}


/* ------------------------------------------
   10. ARTICLE PAGE STYLES
   ------------------------------------------ */

/* Article header */
.article-header {
  text-align: center;
  padding: var(--space-4xl) var(--space-lg) var(--space-xl);
  max-width: 800px;
  margin: 0 auto;
}

.article-header h1 {
  margin-bottom: var(--space-md);
  letter-spacing: -0.02em;
}

.article-header .article-meta {
  font-size: var(--fs-sm);
  color: var(--color-muted);
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
}

/* Prose */
.article-body {
  max-width: 740px;
  margin: 0 auto;
}

.article-body p {
  font-size: var(--fs-md);
  line-height: var(--lh-loose);
  margin-bottom: var(--space-lg);
  color: var(--color-text-secondary);
}

.article-body h2 {
  margin-top: var(--space-2xl);
  scroll-margin-top: calc(var(--nav-height) + var(--space-lg));
}

.article-body h3 {
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
  scroll-margin-top: calc(var(--nav-height) + var(--space-lg));
}

.article-body ul,
.article-body ol {
  margin-bottom: var(--space-lg);
  padding-left: var(--space-xl);
}

.article-body li {
  font-size: var(--fs-md);
  line-height: var(--lh-base);
  margin-bottom: var(--space-sm);
  color: var(--color-text-secondary);
}

.article-body blockquote {
  margin: var(--space-xl) 0;
}

.article-body img {
  border-radius: var(--radius-md);
  margin: var(--space-xl) 0;
}

/* TL;DR Box */
.tldr-box {
  background: var(--color-surface);
  border-left: 4px solid var(--color-primary);
  padding: var(--space-lg) var(--space-xl);
  margin: var(--space-xl) 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.tldr-box strong {
  display: block;
  margin-bottom: var(--space-sm);
  font-size: var(--fs-md);
}

.tldr-box p {
  margin-bottom: var(--space-sm);
  font-size: var(--fs-base);
}

.tldr-box p:last-child {
  margin-bottom: 0;
}

/* Reference list */
.reference-list {
  font-size: var(--fs-sm);
  color: var(--color-muted);
  border-top: 1px solid var(--color-surface);
  padding-top: var(--space-lg);
  margin-top: var(--space-2xl);
}

.reference-list h3 {
  font-size: var(--fs-base);
  margin-bottom: var(--space-md);
}

.reference-list ol {
  padding-left: var(--space-lg);
}

.reference-list li {
  font-size: var(--fs-sm);
  margin-bottom: var(--space-xs);
  color: var(--color-muted);
}

/* Sidebar TOC */
.sidebar-toc {
  position: sticky;
  top: calc(var(--nav-height) + var(--space-lg));
  padding: var(--space-lg);
  background: var(--color-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}

.sidebar-toc h4 {
  font-size: var(--fs-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-muted);
  margin-bottom: var(--space-md);
}

.sidebar-toc ul {
  list-style: none;
  padding: 0;
}

.sidebar-toc li {
  margin-bottom: var(--space-sm);
}

.sidebar-toc a {
  font-size: var(--fs-sm);
  color: var(--color-text-secondary);
  transition: color var(--transition-base);
}

.sidebar-toc a:hover,
.sidebar-toc a.active {
  color: var(--color-primary);
}


/* ------------------------------------------
   11. FAQ ACCORDION
   ------------------------------------------ */
.faq-section {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--color-surface);
}

.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-lg) 0;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-heading);
  font-size: var(--fs-md);
  color: var(--color-text);
  text-align: left;
}

.faq-question::after {
  content: '+';
  font-size: var(--fs-xl);
  color: var(--color-primary);
  transition: transform var(--transition-slow);
  flex-shrink: 0;
  margin-left: var(--space-md);
}

.faq-item.active .faq-question::after {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}

.faq-answer__inner {
  padding: 0 0 var(--space-lg);
}

.faq-answer p {
  font-size: var(--fs-base);
  color: var(--color-text-secondary);
}


/* ------------------------------------------
   12. DATA TABLES (.comparison-table)
   ------------------------------------------ */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-xl) 0;
  font-size: var(--fs-sm);
  border-radius: var(--radius-md);
}

.comparison-table thead {
  background: var(--color-dark);
  color: var(--color-white);
}

.comparison-table th {
  padding: var(--space-md) var(--space-lg);
  text-align: left;
  font-weight: 600;
  font-size: var(--fs-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.comparison-table td {
  padding: var(--space-md) var(--space-lg);
  border-bottom: 1px solid var(--color-surface);
  color: var(--color-text-secondary);
}

.comparison-table tbody tr:hover {
  background: rgba(232, 228, 223, 0.3);
}

.comparison-table tbody tr:nth-child(even) {
  background: rgba(250, 248, 245, 0.5);
}

.comparison-table tbody tr:nth-child(even):hover {
  background: rgba(232, 228, 223, 0.3);
}

/* Table wrapper -- horizontal scroll with fade indicator */
.table-wrapper {
  width: 100%;
  contain: inline-size;  /* content CANNOT expand this element */
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: var(--space-xl) 0;
  position: relative;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}

.table-wrapper .comparison-table {
  margin: 0;
}

/* Mobile: force horizontal scroll in wrapper */
@media (max-width: 768px) {
  .table-wrapper > table {
    width: auto;
    min-width: 580px;
  }
  .comparison-table th,
  .comparison-table td {
    font-size: var(--fs-xs);
    padding: var(--space-sm) var(--space-md);
  }
}


/* ------------------------------------------
   13. GLOBAL FOOTER (.site-footer)
   Supports BOTH BEM (.site-footer__*) and flat (.footer-grid, .footer-bottom)
   ------------------------------------------ */
.site-footer {
  background: var(--color-dark);
  color: var(--color-surface);
  padding: var(--space-4xl) 0 var(--space-xl);
  margin-top: var(--space-4xl);
  overflow: hidden;
  width: 100%;
}

/* Footer grid -- both naming patterns */
.site-footer__grid,
.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}

.site-footer h4 {
  color: var(--color-white);
  font-size: var(--fs-md);
  margin-bottom: var(--space-md);
}

.site-footer p {
  color: var(--color-muted);
  font-size: var(--fs-sm);
  line-height: var(--lh-base);
}

.site-footer ul {
  list-style: none;
  padding: 0;
}

.site-footer ul li {
  margin-bottom: var(--space-sm);
}

.site-footer a {
  color: var(--color-muted);
  font-size: var(--fs-sm);
  transition: color var(--transition-base);
}

.site-footer a:hover {
  color: var(--color-white);
}

/* Footer bottom / disclosure -- both naming patterns */
.site-footer__disclosure,
.footer-bottom {
  font-size: var(--fs-xs);
  color: var(--color-muted);
  line-height: var(--lh-loose);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-lg);
  margin-bottom: var(--space-md);
}

.footer-bottom p {
  font-size: var(--fs-xs);
  color: var(--color-muted);
  margin-bottom: var(--space-sm);
}

.footer-bottom p:last-child {
  margin-bottom: 0;
}

.site-footer__copyright {
  font-size: var(--fs-xs);
  color: var(--color-muted);
  text-align: center;
}


/* ------------------------------------------
   14. BACK TO TOP BUTTON
   ------------------------------------------ */
.back-to-top {
  position: fixed;
  bottom: var(--space-xl);
  right: var(--space-xl);
  width: 44px;
  height: 44px;
  background: var(--color-primary);
  color: var(--color-white);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  font-size: var(--fs-lg);
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-slow), visibility var(--transition-slow), transform var(--transition-base);
  z-index: 900;
  box-shadow: 0 2px 8px rgba(26, 26, 26, 0.15);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(196, 30, 58, 0.3);
}


/* ------------------------------------------
   15. UTILITY CLASSES
   ------------------------------------------ */
.muted {
  color: var(--color-muted);
}

.text-center {
  text-align: center;
}

.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;
}

/* Divider */
.divider {
  border: none;
  border-top: 1px solid var(--color-surface);
  margin: var(--space-3xl) 0;
}


/* ------------------------------------------
   16. RESPONSIVE BREAKPOINTS
   ------------------------------------------ */

/* Tablet: 960px */
@media (max-width: 960px) {
  .article-grid,
  .article-cards {
    grid-template-columns: repeat(2, 1fr);
  }

  .site-footer__grid,
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .hero h1 {
    font-size: var(--fs-3xl);
  }

  h1 { font-size: var(--fs-2xl); }
  h2 { font-size: var(--fs-xl); }
}

/* Mobile: 768px */
@media (max-width: 768px) {
  :root {
    --fs-3xl: 2rem;
    --fs-2xl: 1.5rem;
    --fs-xl: 1.35rem;
    --fs-4xl: 2rem;
  }

  .container {
    padding: 0 var(--space-md);
  }

  /* Hero */
  .hero {
    padding: var(--space-2xl) 0 var(--space-xl);
  }

  .hero h1 {
    font-size: var(--fs-2xl);
  }

  .hero .subtitle,
  .hero .hero-subtitle,
  .hero-subtitle {
    font-size: var(--fs-base);
  }

  .hero-actions,
  .hero-ctas {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions .cta-button,
  .hero-ctas .cta-button {
    text-align: center;
    width: 100%;
  }

  /* Nav mobile -- both naming patterns */
  .site-nav__hamburger,
  .site-nav .nav-toggle {
    display: block;
  }

  .site-nav__links,
  .site-nav .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--color-white);
    flex-direction: column;
    padding: var(--space-lg);
    box-shadow: var(--shadow-nav);
    gap: var(--space-md);
  }

  .site-nav.nav-open .site-nav__links,
  .site-nav.nav-open .nav-links {
    display: flex;
  }

  /* Cards */
  .article-grid,
  .article-cards {
    grid-template-columns: 1fr;
  }

  /* Footer -- both naming patterns */
  .site-footer__grid,
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  /* Email capture -- stack vertically */
  form.email-capture,
  .email-capture__form {
    flex-direction: column;
  }

  form.email-capture .cta-button,
  .email-capture__form .cta-button,
  .email-capture__button {
    width: 100%;
    text-align: center;
  }

  .site-footer form.email-capture,
  .site-footer .email-capture__form {
    flex-direction: column;
  }

  /* CTA buttons full-width on mobile */
  .cta-button {
    width: 100%;
    text-align: center;
  }

  /* Article */
  .article-header {
    padding: var(--space-xl) 0 var(--space-md);
  }

  .article-header h1 {
    font-size: var(--fs-2xl);
  }

  .article-body p,
  .article-body li {
    font-size: var(--fs-base);
  }

  .sidebar-toc {
    position: static;
    margin-bottom: var(--space-xl);
  }

  /* Homepage sections */
  .homepage-section {
    padding: var(--space-2xl) 0;
  }

  .featured-articles {
    padding: var(--space-2xl) 0;
  }

  .methodology-section,
  .methodology-teaser {
    padding: var(--space-2xl) 0;
  }

  .email-section,
  .email-capture-section {
    padding: var(--space-2xl) 0;
  }

  /* Back to top */
  .back-to-top {
    bottom: var(--space-md);
    right: var(--space-md);
  }

  /* About page methodology grid */
  .methodology-grid {
    grid-template-columns: 1fr;
  }

  /* About sections reduced padding */
  .about-section {
    padding: var(--space-xl) 0;
  }

  /* Section header text size */
  .section-header p {
    font-size: var(--fs-base);
  }

  /* Email capture box */
  .email-capture-box {
    padding: var(--space-lg);
  }

  /* All articles list items */
  .articles-list .article-list-item h3 {
    font-size: var(--fs-lg);
  }
}

/* Small mobile: 480px */
@media (max-width: 480px) {
  :root {
    --fs-4xl: 1.75rem;
    --fs-3xl: 1.5rem;
    --fs-2xl: 1.35rem;
  }

  .hero {
    padding: var(--space-xl) 0;
  }

  .article-card__body {
    padding: var(--space-md);
  }

  .site-footer {
    padding: var(--space-2xl) 0 var(--space-md);
  }

  .tldr-box {
    padding: var(--space-md);
  }

  .email-capture-box {
    padding: var(--space-md);
  }
}