/* ============================================================
   Sauna Health Authority - Design System (v2)
   Based on: Health Authority Design System
   Fonts: Newsreader (headings), Inter (body)
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Newsreader:wght@500;600;700&display=swap');

/* --- CSS Variables / Design Tokens --- */
:root {
  /* Colors from DESIGN.md */
  --color-surface: #f7f9fb;
  --color-surface-dim: #d8dadc;
  --color-surface-bright: #f7f9fb;
  --color-surface-container-lowest: #ffffff;
  --color-surface-container-low: #f2f4f6;
  --color-surface-container: #eceef0;
  --color-surface-container-high: #e6e8ea;
  --color-surface-container-highest: #e0e3e5;
  --color-on-surface: #191c1e;
  --color-on-surface-variant: #45464d;
  --color-inverse-surface: #2d3133;
  --color-inverse-on-surface: #eff1f3;
  --color-outline: #76777d;
  --color-outline-variant: #c6c6cd;
  --color-surface-tint: #565e74;
  --color-primary: #000000;
  --color-on-primary: #ffffff;
  --color-primary-container: #131b2e;
  --color-on-primary-container: #7c839b;
  --color-inverse-primary: #bec6e0;
  --color-secondary: #515f74;
  --color-on-secondary: #ffffff;
  --color-secondary-container: #d5e3fd;
  --color-on-secondary-container: #57657b;
  --color-tertiary: #000000;
  --color-on-tertiary: #ffffff;
  --color-tertiary-container: #161c22;
  --color-on-tertiary-container: #7e848c;
  --color-error: #ba1a1a;
  --color-on-error: #ffffff;
  --color-error-container: #ffdad6;
  --color-on-error-container: #93000a;
  --color-primary-fixed: #dae2fd;
  --color-primary-fixed-dim: #bec6e0;
  --color-on-primary-fixed: #131b2e;
  --color-on-primary-fixed-variant: #3f465c;
  --color-secondary-fixed: #d5e3fd;
  --color-secondary-fixed-dim: #b9c7e0;
  --color-on-secondary-fixed: #0d1c2f;
  --color-on-secondary-fixed-variant: #3a485c;
  --color-tertiary-fixed: #dde3eb;
  --color-tertiary-fixed-dim: #c1c7cf;
  --color-on-tertiary-fixed: #161c22;
  --color-on-tertiary-fixed-variant: #41474e;
  --color-background: #f7f9fb;
  --color-on-background: #191c1e;
  --color-surface-variant: #e0e3e5;

  /* Typography Families */
  --font-heading: 'Newsreader', Georgia, 'Times New Roman', serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;

  /* Spacing (8px base) */
  --spacing-base: 8px;
  --container-max: 1120px;
  --gutter: 24px;
  --margin-mobile: 16px;
  --section-gap: 80px;

  /* Border Radius (from DESIGN.md) */
  --radius-sm: 0.125rem;    /* 2px */
  --radius-md: 0.25rem;     /* 4px - DEFAULT */
  --radius-lg: 0.375rem;    /* 6px */
  --radius-xl: 0.5rem;      /* 8px */
  --radius-xxl: 0.75rem;    /* 12px */
  --radius-full: 9999px;

  /* Shadows (tonal, low-contrast) */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 2px 8px rgba(0,0,0,0.04);
  --shadow-lg: 0 4px 12px rgba(0,0,0,0.04);

  /* Transitions */
  --transition: 0.2s ease;

  /* Legacy aliases (mapped to new tokens) */
  --color-primary-dark: var(--color-primary-container);
  --color-primary-light: var(--color-secondary);
  --color-accent: var(--color-secondary);
  --color-accent-dark: var(--color-on-secondary-container);
  --color-bg: var(--color-surface);
  --color-white: var(--color-surface-container-lowest);
  --color-text: var(--color-on-surface);
  --color-text-light: var(--color-on-surface-variant);
  --color-border: var(--color-outline-variant);
  --color-footer-bg: var(--color-primary-container);
  --color-footer-text: var(--color-on-primary-container);
  --font-primary: var(--font-body);
  --max-width: var(--container-max);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-on-surface);
  background: var(--color-surface);
  overflow-x: hidden;
}

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

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

img {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-xl);
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* ============================================================
   HEADER / NAVIGATION
   ============================================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--color-surface-container-lowest);
  border-bottom: 1px solid var(--color-outline-variant);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
  height: 70px;
}

.logo a {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.3rem;
  font-weight: 700;
  font-family: var(--font-heading);
  color: var(--color-primary);
  text-decoration: none;
}

.logo a:hover {
  text-decoration: none;
}

.logo img {
  width: 42px;
  height: 42px;
  object-fit: contain;
}

/* --- Navigation --- */
.main-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.main-nav > a {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 0.9rem;
  color: var(--color-on-surface);
  padding: 8px 0;
  position: relative;
  transition: color var(--transition);
}

.main-nav > a:hover,
.main-nav > a.active {
  color: var(--color-primary);
  text-decoration: none;
}

.main-nav > a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width var(--transition);
}

.main-nav > a:hover::after,
.main-nav > a.active::after {
  width: 100%;
}

/* --- Dropdown Menu --- */
.dropdown {
  position: relative;
}

.dropdown-toggle {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 0.9rem;
  color: var(--color-on-surface);
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px 0;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: color var(--transition);
}

.dropdown-toggle:hover {
  color: var(--color-primary);
}

.dropdown-toggle .arrow {
  font-size: 0.7rem;
  transition: transform var(--transition);
}

.dropdown:hover .dropdown-toggle .arrow {
  transform: rotate(180deg);
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  min-width: 280px;
  max-height: 70vh;
  overflow-y: auto;
  padding: 8px 0;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  z-index: 999;
  border: 1px solid var(--color-outline-variant);
}

.dropdown:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.dropdown-menu a {
  display: block;
  padding: 10px 20px;
  font-size: 0.85rem;
  font-family: var(--font-body);
  color: var(--color-on-surface);
  transition: all var(--transition);
  border-left: 3px solid transparent;
}

.dropdown-menu a:hover {
  background: var(--color-surface-container-low);
  color: var(--color-primary);
  border-left-color: var(--color-primary);
  text-decoration: none;
}

/* --- Mobile Menu Toggle --- */
.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.mobile-toggle span {
  display: block;
  width: 26px;
  height: 2px;
  background: var(--color-on-surface);
  border-radius: 2px;
  transition: all var(--transition);
}

/* --- Contact Button (Header) --- */
.contact-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-secondary);
  color: var(--color-on-secondary) !important;
  padding: 10px 24px !important;
  border-radius: var(--radius-full);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.85rem;
  transition: all var(--transition);
  border: none;
  cursor: pointer;
}

.contact-btn:hover {
  background: var(--color-on-secondary-container);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
  color: var(--color-on-secondary) !important;
  text-decoration: none;
}

.contact-btn::after {
  display: none !important;
}

/* ============================================================
   HERO / PAGE HEADER
   ============================================================ */

.page-hero {
  background: var(--color-surface-container-lowest);
  color: var(--color-on-surface);
  padding: 60px 20px;
  text-align: center;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--color-outline-variant);
}

.page-hero::before {
  display: none;
}

.page-hero h1 {
  font-family: var(--font-heading);
  font-size: 48px;
  font-weight: 600;
  line-height: 1.1;
  margin-bottom: 12px;
  position: relative;
  letter-spacing: -0.02em;
  color: var(--color-primary);
}

.page-hero h1 a {
  color: var(--color-primary);
  text-decoration: none;
}

.page-hero h1 a:hover {
  text-decoration: underline;
}

.page-hero p {
  font-family: var(--font-body);
  font-size: 18px;
  line-height: 1.6;
  font-weight: 400;
  opacity: 0.85;
  max-width: 700px;
  margin: 0 auto;
  position: relative;
  color: var(--color-on-surface);
}

/* ============================================================
   MAIN CONTENT
   ============================================================ */

.main-content {
  padding: var(--section-gap) 0;
}

.content-grid {
  max-width: var(--container-max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 50px;
  align-items: start;
}

.content-main {
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-xl);
  padding: 40px;
  border: 1px solid var(--color-outline-variant);
}

.content-main h2 {
  font-family: var(--font-heading);
  font-size: 32px;
  font-weight: 600;
  line-height: 1.2;
  color: var(--color-primary);
  margin: 48px 0 16px 0;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-outline-variant);
  position: relative;
}

.content-main h2:first-child {
  margin-top: 0;
}

.content-main p {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  font-weight: 400;
  margin-bottom: 18px;
  color: var(--color-on-surface-variant);
}

/* --- Content List / Reference URLs --- */
.content-main ul {
  list-style: none;
  padding: 0;
}

.content-main ul li {
  padding: 6px 0;
  border-bottom: 1px solid var(--color-outline-variant);
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.4;
  font-weight: 400;
}

.content-main ul li a {
  color: var(--color-secondary);
}

.content-main ul li a:hover {
  color: var(--color-primary);
}

/* --- Sidebar --- */
.sidebar {
  position: sticky;
  top: 90px;
}

.sidebar-card {
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-xl);
  padding: 24px;
  border: 1px solid var(--color-outline-variant);
  margin-bottom: 24px;
}

.sidebar-card h3 {
  font-family: var(--font-heading);
  font-size: 20px;
  font-weight: 500;
  line-height: 1.3;
  color: var(--color-primary);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--color-outline-variant);
}

.sidebar-card p {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.6;
  color: var(--color-on-surface-variant);
}

.sidebar-cta {
  display: inline-block;
  margin-top: 12px;
  background: var(--color-secondary);
  color: var(--color-on-secondary);
  padding: 10px 24px;
  border-radius: var(--radius-full);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.85rem;
  transition: all var(--transition);
}

.sidebar-cta:hover {
  background: var(--color-on-secondary-container);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
  color: var(--color-on-secondary);
  text-decoration: none;
}

/* --- Researchers Table --- */
.researchers-table {
  padding: var(--section-gap) 0;
}

.researchers-table h2 {
  font-family: var(--font-heading);
  font-size: 24px;
  font-weight: 500;
  line-height: 1.3;
  color: var(--color-primary);
  margin-bottom: 20px;
}

.researchers-table table {
  font-size: 0.75rem;
  width: 100%;
  border-collapse: collapse;
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-xl);
  overflow: hidden;
  border: 1px solid var(--color-outline-variant);
}

.researchers-table table td {
  padding: 4px 10px;
  vertical-align: top;
  font-family: var(--font-body);
  font-size: 12px;
  color: var(--color-on-surface-variant);
  border-bottom: 1px solid var(--color-outline-variant);
}

.researchers-table table tr:last-child td {
  border-bottom: none;
}

/* --- TikTok Embed --- */
.tiktok-embed {
  margin: 30px 0;
  text-align: center;
}

/* --- Random Image Placeholder --- */
#random-image-placeholder {
  margin: 24px 0;
}

#random-image-placeholder img {
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-xl);
  border: 1px solid var(--color-outline-variant);
}

/* ============================================================
   FOOTER
   ============================================================ */

.site-footer {
  background: var(--color-primary-container);
  color: var(--color-on-primary-container);
  padding: 60px 0 30px;
  border-top: 1px solid var(--color-outline-variant);
}

.footer-grid {
  max-width: var(--container-max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  padding: 0 var(--gutter);
}

.footer-col h4 {
  font-family: var(--font-heading);
  color: var(--color-on-secondary);
  font-size: 1.1rem;
  margin-bottom: 18px;
  position: relative;
  padding-bottom: 10px;
}

.footer-col h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 2px;
  background: var(--color-secondary);
}

.footer-col p {
  font-family: var(--font-body);
  font-size: 0.85rem;
  line-height: 1.7;
  margin-bottom: 16px;
  color: var(--color-on-primary-container);
}

.footer-col ul {
  list-style: none;
}

.footer-col ul li {
  margin-bottom: 10px;
}

.footer-col ul li a {
  color: var(--color-on-primary-container);
  font-family: var(--font-body);
  font-size: 0.85rem;
  transition: all var(--transition);
}

.footer-col ul li a:hover {
  color: var(--color-on-secondary);
  padding-left: 4px;
  text-decoration: none;
}

.social-links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.social-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  background: rgba(255,255,255,0.08);
  border-radius: 50%;
  color: var(--color-on-primary-container);
  font-size: 0.7rem;
  font-family: var(--font-body);
  font-weight: 600;
  transition: all var(--transition);
}

.social-links a:hover {
  background: var(--color-secondary);
  color: var(--color-on-secondary);
  transform: translateY(-2px);
  text-decoration: none;
}

.footer-bottom {
  max-width: var(--container-max);
  margin: 40px auto 0;
  padding: 20px var(--gutter) 0;
  border-top: 1px solid rgba(255,255,255,0.08);
  text-align: center;
  font-family: var(--font-body);
  font-size: 0.8rem;
  color: var(--color-on-primary-container);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */

@media (max-width: 920px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-hero h1 {
    font-size: 32px;
  }

  .content-main h2 {
    font-size: 28px;
  }
}

@media (max-width: 768px) {
  .mobile-toggle {
    display: flex;
  }

  .main-nav {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 70px;
    left: 0;
    width: 100%;
    background: var(--color-surface-container-lowest);
    box-shadow: var(--shadow-md);
    padding: 20px;
    gap: 12px;
    border-bottom: 1px solid var(--color-outline-variant);
  }

  .main-nav.open {
    display: flex;
  }

  .main-nav > a,
  .dropdown-toggle {
    width: 100%;
    text-align: left;
    padding: 12px 0;
  }

  .dropdown-menu {
    position: static;
    transform: none;
    box-shadow: none;
    border: none;
    opacity: 1;
    visibility: visible;
    max-height: 0;
    overflow: hidden;
    padding: 0;
    background: var(--color-surface-container-low);
    border-radius: var(--radius-md);
    transition: max-height var(--transition), padding var(--transition);
  }

  .dropdown.active .dropdown-menu {
    max-height: 2000px;
    padding: 8px 0;
  }

  .dropdown-menu a {
    padding: 10px 20px;
  }

  .content-grid {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
  }

  .page-hero h1 {
    font-size: 28px;
    line-height: 1.2;
  }

  .page-hero p {
    font-size: 16px;
  }

  .content-main {
    padding: 24px;
  }

  .content-main h2 {
    font-size: 24px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .container {
    padding: 0 var(--margin-mobile);
  }

  .main-content {
    padding: 40px 0;
  }
}