@media (max-width: 820px) {
  body {
    font-size: 13px;
  }

  header {
    position: sticky;
    top: 0;
    z-index: 1100;
    background: #fff;
    box-shadow: 0 8px 24px rgba(15, 23, 42, 0.12);
    border-bottom: 1px solid #e2e8f0;
    display: block;
    width: 100%;
  }

  .nav {
    flex-direction: column;
    align-items: center;
    gap: 0.45rem;
    padding: 0.75rem 1rem 0.9rem;
    max-width: none;
    width: 100%;
    margin: 0;
    background: #fff;
    border-radius: 0 0 16px 16px;
  }

  .brand {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .brand span {
    font-size: 0.88rem;
  }

  .mobile-menu-container {
    display: flex;
    width: 100%;
    justify-content: center;
    align-items: center;
    gap: 0.75rem;
    margin-top: 0.25rem;
  }

  .mobile-menu-toggle {
    display: inline-flex;
    flex-direction: row;
    justify-content: center;
    align-items: center;
    gap: 8px;
    width: auto;
    height: 38px;
    background: #0369a1;
    border: none;
    border-radius: 10px;
    padding: 6px 10px;
    box-shadow: 0 10px 20px rgba(3, 105, 161, 0.18);
    margin: 0 auto;
  }

  .mobile-menu-toggle .menu-bars {
    display: flex;
    flex-direction: column;
    gap: 5px;
  }

  .mobile-menu-toggle .menu-bars span {
    display: block;
    height: 3px;
    width: 24px;
    background: #fff;
    border-radius: 999px;
    transition: transform 0.2s ease, opacity 0.2s ease;
  }

  .mobile-menu-toggle.active .menu-bars span:nth-child(1) {
    transform: translateY(4px) rotate(45deg);
  }

  .mobile-menu-toggle.active .menu-bars span:nth-child(2) {
    opacity: 0;
  }

  .mobile-menu-toggle.active .menu-bars span:nth-child(3) {
    transform: translateY(-4px) rotate(-45deg);
  }

  .mobile-menu-toggle .menu-label {
    color: #fff;
    font-weight: 700;
    font-size: 0.9rem;
    letter-spacing: 0.01em;
  }

  .tabs {
    position: static;
    top: auto;
    left: auto;
    right: auto;
    transform: none;
    box-shadow: none;
    display: none;
    flex-direction: column;
    align-items: stretch;
    width: 100%;
    gap: 0.3rem;
    background: #fff;
    border-radius: 10px;
    border: 1px solid #e5e7eb;
    padding: 0.35rem 0.4rem;
  }

  .tabs.active {
    display: flex;
  }

  .tab {
    text-align: left;
    font-size: 0.9rem;
    padding: 0.55rem 0.7rem;
  }

  .toggle span {
    font-size: 0.85rem;
  }

  .actions {
    position: relative;
    left: 0;
    width: 100%;
    display: flex;
    justify-content: center;
    margin: 0.35rem 0 0.5rem;
  }

  .section {
    padding: 1.25rem 0;
  }

  .container {
    padding: 0 0.95rem;
  }

  .hero h1,
  .hero-alt h1,
  .hero-breast h1,
  .hero-cervical h1,
  .hero-colon h1,
  .hero-lung h1,
  .hero-prostate h1 {
    font-size: 1.8rem;
    margin-bottom: 0.9rem;
  }

  .info-panel,
  .detail-intro,
  .detail-card,
  .detail-note,
  .learn-card,
  .learn-intro {
    padding: 0.9rem 1rem;
    border-radius: 12px;
  }

  .info-block {
    gap: 1rem;
    flex-direction: column;
  }

  .detail-grid,
  .learn-grid {
    grid-template-columns: 1fr;
    gap: 0.9rem;
  }

  .cancer-cards.cancer-cards--row {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }

  .cancer-card {
    padding: 0.9rem 1rem;
    border-radius: 12px;
  }

  .mission-hero .container,
  .why-overview__stack {
    gap: 1rem;
  }

  .mission-hero h1 {
    font-size: 2.1rem;
    text-align: center;
  }

  .mission-hero p {
    text-align: center;
  }

  .why-overview__block {
    padding: 1.35rem;
  }

  .why-overview__block h1 {
    font-size: 1.5rem;
  }

  .why-overview__block p,
  .why-overview__list {
    font-size: 0.9rem;
  }

  .chatbot-toggle {
    width: 50px;
    height: 50px;
    bottom: 12px;
    right: 12px;
  }

  .chatbot-container {
    max-height: 90vh;
    width: 100%;
    max-width: none;
    right: 0;
    left: 0;
    bottom: 0;
    border-radius: 0;
  }

  .chatbot-header {
    padding: 0.6rem 0.85rem;
  }

  .chatbot-messages {
    padding: 0.7rem;
  }

  .chatbot-input-wrapper {
    gap: 0.45rem;
  }

  .learn-meta {
    gap: 0.45rem;
  }

  .pill {
    font-size: 0.78rem;
    padding: 0.25rem 0.5rem;
  }

  ul {
    padding-left: 0.9rem;
  }

  .info-card,
  .definition-bubble {
    padding: 0.85rem 0.95rem;
  }

  /* Make cancer tiles readable on small screens */
  .cancer-cards {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.85rem;
    overflow: visible;
  }

  .cancer-card {
    width: 100%;
    text-align: left;
    min-width: 0;
  }

  /* Remove hover effects on mobile */
  a:hover,
  .tab:hover,
  .cancer-card:hover,
  .why-card:hover {
    background: inherit;
    color: inherit;
    transform: none;
    box-shadow: none;
  }
}