/* =====================================================
   REDOX HEALTH SCIENCE — MAIN STYLESHEET
   File: redox.css
===================================================== */

:root {
  --redox-blue-dark: #12384f;
  --redox-blue: #1f5f7a;
  --redox-aqua: #2dc4c4;
  --redox-soft: #eef8f8;
  --redox-light: #f6fbfb;
  --redox-line: #dbe7ec;
  --redox-text: #24323a;
  --redox-muted: #647681;
  --redox-white: #ffffff;
  --redox-shadow: rgba(15, 58, 85, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  color: var(--redox-text);
  background: var(--redox-white);
  line-height: 1.6;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: var(--redox-blue);
}

a:hover {
  color: var(--redox-aqua);
}

main {
  width: 100%;
}

/* =====================================================
   HEADER — DESKTOP + MOBILE ACCORDION
===================================================== */

.site-header {
  background: #ffffff;
  border-bottom: 1px solid var(--redox-line);
  position: relative;
  z-index: 10000;
}

.header-inner {
  max-width: 1300px;
  margin: 0 auto;
  padding: 18px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 30px;
}

.logo {
  color: var(--redox-blue-dark);
  font-size: 24px;
  font-weight: 900;
  letter-spacing: 0.3px;
  text-decoration: none;
  white-space: nowrap;
}

.logo span {
  color: var(--redox-aqua);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.main-nav > a,
.nav-parent > a {
  color: var(--redox-blue-dark);
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
  padding: 10px 0;
  display: block;
}

.main-nav > a:hover,
.nav-parent > a:hover {
  color: var(--redox-aqua);
}

.nav-dropdown {
  position: relative;
}

.nav-parent {
  display: block;
}

.dropdown-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 245px;
  background: #ffffff;
  border: 1px solid var(--redox-line);
  box-shadow: 0 8px 22px rgba(15, 58, 85, 0.14);
  z-index: 99999;
  padding: 8px 0;
  border-radius: 10px;
}

.dropdown-menu a {
  display: block;
  padding: 12px 16px;
  color: var(--redox-blue-dark);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}

.dropdown-menu a:hover {
  background: var(--redox-soft);
  color: var(--redox-aqua);
}

@media (min-width: 901px) {
  .nav-dropdown:hover > .dropdown-menu {
    display: block;
  }

  .mobile-menu-toggle,
  .submenu-toggle {
    display: none;
  }
}

/* =====================================================
   MOBILE HAMBURGER + ACCORDION MENU
===================================================== */

.mobile-menu-toggle {
  display: none;
  border: none;
  background: transparent;
  color: var(--redox-blue-dark);
  font-size: 30px;
  font-weight: 800;
  cursor: pointer;
  padding: 4px 8px;
  line-height: 1;
}

.submenu-toggle {
  display: none;
  border: none;
  background: transparent;
  color: var(--redox-blue-dark);
  font-size: 24px;
  font-weight: 800;
  cursor: pointer;
  padding: 6px 10px;
  line-height: 1;
}

@media (max-width: 900px) {
  .header-inner {
    flex-wrap: wrap;
    align-items: center;
  }

  .mobile-menu-toggle {
    display: block;
    margin-left: auto;
  }

  .main-nav {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin-top: 14px;
    border-top: 1px solid var(--redox-line);
  }

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

  .main-nav > a {
    padding: 13px 0;
    border-bottom: 1px solid var(--redox-line);
  }

  .nav-dropdown {
    width: 100%;
    position: static;
  }

  .nav-parent {
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--redox-line);
  }

  .nav-parent > a {
    flex: 1;
    padding: 13px 0;
  }

  .submenu-toggle {
    display: inline-block;
    flex: 0 0 auto;
  }

  .dropdown-menu {
    display: none;
    position: static;
    min-width: 0;
    box-shadow: none;
    border: none;
    border-left: 3px solid var(--redox-aqua);
    border-radius: 0;
    padding: 6px 0 10px 16px;
    margin: 0 0 8px 0;
    background: transparent;
  }

  .nav-dropdown.is-open > .dropdown-menu {
    display: block;
  }

  .nav-dropdown.is-open .submenu-toggle {
    transform: rotate(45deg);
  }

  .dropdown-menu a {
    padding: 9px 0;
    font-size: 15px;
    white-space: normal;
  }
}

/* =====================================================
   HERO / PAGE INTRO
===================================================== */

.hero-placeholder {
  background: linear-gradient(135deg, var(--redox-blue-dark), var(--redox-blue));
  color: #ffffff;
  text-align: center;
  padding: 90px 24px;
}

.hero-placeholder h1 {
  font-size: 52px;
  line-height: 1.15;
  margin: 0 0 20px;
}

.hero-placeholder p {
  max-width: 900px;
  margin: 0 auto;
  font-size: 21px;
  line-height: 1.7;
}

/* =====================================================
   GENERAL SECTIONS
===================================================== */

.redox-section {
  padding: 64px 24px;
  background: #ffffff;
}

.redox-section.feature {
  background: var(--redox-light);
}

.section-title {
  max-width: 980px;
  margin: 0 auto 38px;
  text-align: center;
}

.section-title h2 {
  color: var(--redox-blue-dark);
  font-size: 40px;
  line-height: 1.2;
  margin: 0 0 16px;
}

.section-title p {
  color: var(--redox-muted);
  font-size: 18px;
  line-height: 1.7;
  margin: 0;
}

/* =====================================================
   CARD LAYOUTS
===================================================== */

.cards {
  max-width: 1180px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 26px;
}

.card {
  background: #ffffff;
  padding: 30px 28px;
  border-radius: 14px;
  box-shadow: 0 8px 24px var(--redox-shadow);
}

.card h3 {
  color: var(--redox-blue-dark);
  font-size: 23px;
  line-height: 1.25;
  margin: 0 0 14px;
}

.card p {
  color: var(--redox-text);
  font-size: 16px;
  line-height: 1.65;
  margin: 0;
}

.card a {
  color: var(--redox-blue);
  font-weight: 700;
  text-decoration: none;
}

.card a:hover {
  color: var(--redox-aqua);
  text-decoration: underline;
}

/* =====================================================
   TWO COLUMN PANELS
===================================================== */

.two-col {
  max-width: 1180px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.list-panel {
  background: #ffffff;
  padding: 30px 28px;
  border-radius: 14px;
  box-shadow: 0 8px 24px var(--redox-shadow);
}

.list-panel h3 {
  color: var(--redox-blue-dark);
  font-size: 24px;
  margin: 0 0 16px;
}

.list-panel p {
  margin-top: 0;
}

.list-panel ul {
  margin: 0;
  padding-left: 22px;
}

.list-panel li {
  margin-bottom: 10px;
}

/* =====================================================
   RESEARCH / FEATURE LIST
===================================================== */

.research-list {
  max-width: 980px;
  margin: 0 auto;
}

.research-item {
  background: #ffffff;
  padding: 24px 26px;
  border-left: 5px solid var(--redox-aqua);
  border-radius: 10px;
  box-shadow: 0 6px 18px var(--redox-shadow);
  margin-bottom: 18px;
}

.research-item strong {
  color: var(--redox-blue-dark);
  font-size: 18px;
}

/* =====================================================
   BUTTONS
===================================================== */

.redox-button,
.primary-btn,
.secondary-btn {
  display: inline-block;
  padding: 13px 24px;
  border-radius: 999px;
  font-size: 16px;
  font-weight: 700;
  text-decoration: none;
  line-height: 1.2;
}

.redox-button,
.primary-btn {
  background: var(--redox-aqua);
  color: #ffffff;
}

.redox-button:hover,
.primary-btn:hover {
  background: var(--redox-blue-dark);
  color: #ffffff;
}

.secondary-btn {
  background: #ffffff;
  color: var(--redox-blue-dark);
  border: 2px solid var(--redox-aqua);
}

.secondary-btn:hover {
  background: var(--redox-aqua);
  color: #ffffff;
}

/* =====================================================
   VIDEOS PAGE — CURRENT REDOX HTML STRUCTURE
   Accordion index + video spacing
===================================================== */

#video-index {
  padding-top: 48px;
  padding-bottom: 80px;
}

.video-index-box {
  max-width: 950px;
  margin: 0 auto 80px;
  background: #ffffff;
  border-radius: 12px;
  box-shadow: 0 6px 18px var(--redox-shadow);
  overflow: hidden;
  padding: 0;
}

.video-index-box > summary {
  cursor: pointer;
  padding: 20px 24px;
  font-size: 24px;
  font-weight: 800;
  color: var(--redox-blue-dark);
  list-style: none;
}

.video-index-box > summary::-webkit-details-marker,
.nested-video-group > summary::-webkit-details-marker {
  display: none;
}

.video-index-box > summary::before {
  content: "+";
  display: inline-block;
  margin-right: 12px;
  color: var(--redox-aqua);
  font-size: 28px;
  font-weight: 800;
}

.video-index-box[open] > summary::before {
  content: "−";
}

.nested-video-group {
  border-top: 1px solid var(--redox-line);
}

.nested-video-group > summary {
  cursor: pointer;
  padding: 16px 28px;
  font-size: 20px;
  font-weight: 700;
  color: var(--redox-blue-dark);
  list-style: none;
}

.nested-video-group > summary::before {
  content: "+";
  display: inline-block;
  margin-right: 10px;
  color: var(--redox-aqua);
  font-size: 24px;
  font-weight: 800;
}

.nested-video-group[open] > summary::before {
  content: "−";
}

.nested-video-group ul {
  list-style: none;
  padding: 0 28px 22px 62px;
  margin: 0;
}

.nested-video-group li {
  margin-bottom: 12px;
}

.nested-video-group a {
  color: var(--redox-blue);
  font-weight: 600;
  text-decoration: none;
}

.nested-video-group a:hover {
  color: var(--redox-aqua);
  text-decoration: underline;
}

/* Extra spacing between index and first video */

.video-grid {
  margin-top: 70px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 34px;
  align-items: start;
}

.video-item {
  background: #ffffff;
  padding: 28px;
  border-radius: 12px;
  box-shadow: 0 8px 22px var(--redox-shadow);
  margin-bottom: 70px;
}

.video-item h3 {
  color: var(--redox-blue-dark);
  font-size: 22px;
  line-height: 1.3;
  margin: 20px 0 14px;
}

.video-item p {
  margin-bottom: 14px;
}

.video-wrapper {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  border-radius: 10px;
  background: #000000;
}

.video-wrapper iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.back-to-index {
  margin-top: 18px;
  margin-bottom: 38px;
}

.back-to-index a {
  color: var(--redox-blue);
  font-weight: 700;
  text-decoration: none;
}

.back-to-index a:hover {
  color: var(--redox-aqua);
  text-decoration: underline;
}

@media (max-width: 850px) {
  .video-grid {
    grid-template-columns: 1fr;
    margin-top: 50px;
  }

  .video-item {
    padding: 22px;
  }

  .video-index-box > summary {
    font-size: 21px;
  }

  .nested-video-group > summary {
    font-size: 18px;
  }
}

/* =====================================================
   NOTICES / DISCLAIMERS
===================================================== */

.notice {
  max-width: 980px;
  margin: 0 auto;
  background: var(--redox-soft);
  border-left: 5px solid var(--redox-aqua);
  padding: 28px 30px;
  border-radius: 12px;
}

.notice h2 {
  color: var(--redox-blue-dark);
  margin-top: 0;
}

.notice p {
  margin-bottom: 0;
}

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

.site-footer {
  background: var(--redox-blue-dark);
  color: #dce9ee;
  padding: 54px 24px 24px;
}

.footer-inner {
  max-width: 1300px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 42px;
  align-items: start;
}

.footer-brand h2 {
  color: #ffffff;
  font-size: 26px;
  margin: 0 0 14px;
}

.footer-brand p {
  color: #dce9ee;
  margin: 0;
  line-height: 1.7;
}

.footer-column h3 {
  color: #ffffff;
  font-size: 18px;
  margin: 0 0 16px;
}

.footer-links,
.social-links {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-links li,
.social-links li {
  margin-bottom: 10px;
}

.site-footer a {
  color: #ffffff;
  text-decoration: none;
  font-weight: 600;
}

.site-footer a:hover {
  color: var(--redox-aqua);
  text-decoration: underline;
}

.footer-bottom {
  max-width: 1300px;
  margin: 38px auto 0;
  padding-top: 18px;
  border-top: 1px solid rgba(255,255,255,0.18);
  text-align: center;
}

.footer-bottom p,
.footer-bottom div {
  color: #c8d8df;
  font-size: 14px;
  margin: 0 0 8px;
}

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

@media (max-width: 1100px) {
  .cards {
    grid-template-columns: repeat(2, 1fr);
  }

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

@media (max-width: 850px) {
  .hero-placeholder {
    padding: 72px 22px;
  }

  .hero-placeholder h1 {
    font-size: 40px;
  }

  .hero-placeholder p {
    font-size: 19px;
  }

  .section-title h2,
  .video-library-title,
  .video-index-title {
    font-size: 32px;
  }

  .two-col {
    grid-template-columns: 1fr;
  }

  .video-library-grid {
    grid-template-columns: 1fr;
  }

  .video-author-block h3 {
    font-size: 26px;
  }

  .video-library-card,
  .video-card,
  .video-item {
    padding: 22px;
  }

  .video-index-section {
    padding: 42px 20px 58px;
  }

  .video-index-item summary {
    font-size: 20px;
    padding: 16px 20px;
  }

  .video-index-item ul {
    padding-left: 48px;
  }

  .video-library-section,
  .video-group-section {
    padding-top: 60px;
  }
}

@media (max-width: 700px) {
  .cards {
    grid-template-columns: 1fr;
  }

  .redox-section,
  .video-index-section,
  .video-library-section,
  .video-group-section {
    padding-left: 20px;
    padding-right: 20px;
  }

  .card,
  .list-panel {
    padding: 24px 22px;
  }
}

@media (max-width: 650px) {
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .site-footer {
    padding: 42px 22px 20px;
  }
}