* {
      box-sizing: border-box;
    }

    html, body {
      height: 100%;
      margin: 0;
      display: flex;
      flex-direction: column;
      font-family: 'Segoe UI', sans-serif;
      background-color: #fdfeff;
      color: #333;
    }

    header {
      background: linear-gradient(90deg, #2c3e50, #34495e);
      color: #ffffff;
      padding: 40px 20px;
      text-align: center;
      background-size: cover;
      background-position: center;
    }

    header h1 {
      font-size: 2.5rem;
      margin-bottom: 10px;
      text-shadow: 1px 1px 2px #000;
    }

    header p {
      font-size: 1.1rem;
      text-shadow: 1px 1px 1px #000;
    }

    nav {
      display: flex;
      justify-content: center;
      gap: 30px;
      padding: 15px 10px;
      background-color: #02000b;
      border-bottom: 1px solid #ddd;
    }

    nav a {
       color: white;
      text-decoration: none;
      font-weight: 500;
      font-size: 1rem;
      padding: 8px 0;
      position: relative;
      transition: color 0.3s;
    }

    nav a:not(.dropdown-toggle)::after {
      content: '';
      position: absolute;
      width: 0%;
      height: 2px;
      bottom: 0;
      left: 0;
      background-color: whitesmoke;
      transition: width 0.3s ease;
    }

    nav a:hover {
      color: whitesmoke;
    }

    nav a:not(.dropdown-toggle):hover::after {
      width: 100%;
    }

    main {
      flex: 1;
      width: 100%;
      max-width: 900px;
      margin: 30px auto;
      padding: 0 20px;
    }

    /* Card-like style for large screens */
    @media (min-width: 1025px) {
      main {
        background: white;
        border-radius: 10px;
        box-shadow: 0 0 20px rgba(0,0,0,0.05);
        padding: 30px;
      }
    }

    section {
      margin-bottom: 40px;
    }

    h2 {
      color: #2c3e50;
      font-size: 1.5rem;
    }

    p, li {
      font-size: 1rem;
      line-height: 1.6;
    }

    ul {
      padding-left: 20px;
    }

    section img {
      width: 100%;
      border-radius: 8px;
      margin-top: 10px;
    }

    .footer {
      background-color: #2c3e50;
      color: white;
      text-align: center;
      padding: 10px;
      font-size: 0.8em;
    }

    /* === Popup/Modal Styles === */
    .popup {
      display: none;
      position: fixed;
      z-index: 1000;
      left: 0;
      top: 0;
      width: 100%;
      height: 100%;
      background-color: rgba(44, 62, 80, 0.8);
      animation: fadeIn 0.3s ease;
    }

    @keyframes fadeIn {
      from {
        opacity: 0;
      }
      to {
        opacity: 1;
      }
    }

    .popup-content {
      background-color: #fdfeff;
      margin: 2% auto;
      padding: 0;
      border: 1px solid #ddd;
      width: 90%;
      height: 90%;
      border-radius: 10px;
      position: relative;
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
      animation: slideDown 0.3s ease;
    }

    @keyframes slideDown {
      from {
        transform: translateY(-50px);
        opacity: 0;
      }
      to {
        transform: translateY(0);
        opacity: 1;
      }
    }

    .popup-close {
      color: #999;
      position: absolute;
      right: 15px;
      top: 15px;
      font-size: 32px;
      font-weight: bold;
      cursor: pointer;
      z-index: 1001;
      background-color: white;
      border-radius: 50%;
      width: 45px;
      height: 45px;
      display: flex;
      align-items: center;
      justify-content: center;
      line-height: 1;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
      transition: all 0.3s ease;
    }

    .popup-close:hover,
    .popup-close:focus {
      color: #2c3e50;
      background-color: #f0f0f0;
      transform: rotate(90deg);
    }

    .popup-content iframe {
      width: 100%;
      height: 100%;
      border: none;
      border-radius: 10px;
    }

    /* Hide patients link by default */
    #patients-link {
      display: none;
    }

    /* === Dropdown Menu Styles === */
    .dropdown {
      position: relative;
      display: flex;
      align-items: center;
    }

    .dropdown-toggle {
      cursor: pointer;
      color: white;
      text-decoration: none;
      font-weight: 500;
      font-size: 1rem;
      padding: 8px 0;
      position: relative;
      transition: color 0.3s;
      display: inline-block;
    }

    .dropdown-toggle::after {
      content: '▼';
      font-size: 0.6rem;
      transition: transform 0.3s;
      display: inline-block;
      margin-left: 5px;
    }

    .dropdown.active .dropdown-toggle::after {
      transform: rotate(180deg);
    }

    .dropdown-menu {
      display: none;
      position: absolute;
      top: 100%;
      left: 0;
      background-color: white;
      min-width: 180px;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
      border-radius: 8px;
      margin-top: 10px;
      z-index: 1000;
      overflow: hidden;
    }

    .dropdown.active .dropdown-menu {
      display: block;
      animation: dropdownFade 0.2s ease;
    }

    @keyframes dropdownFade {
      from {
        opacity: 0;
        transform: translateY(-10px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    .dropdown-menu a {
      display: block;
      padding: 12px 20px;
      color: #333;
      text-decoration: none;
      font-weight: 400;
      transition: background-color 0.2s;
    }

    .dropdown-menu a:hover {
      background-color: #f5f5f5;
      color: #2c3e50;
    }

    .dropdown-menu a::after {
      display: none;
    }

    /* === Responsive Styles === */
    @media (max-width: 768px) {
      header h1 {
        font-size: 2rem;
      }

      header p {
        font-size: 1rem;
      }

      nav {
        flex-direction: column;
        align-items: center;
      }

      nav a {
        width: 100%;
        text-align: center;
        padding: 12px;
      }

      main {
        padding: 0 15px;
      }

      .popup-content {
        width: 95%;
        height: 95%;
        margin: 2.5% auto;
      }

      .popup-close {
        width: 40px;
        height: 40px;
        font-size: 28px;
        right: 10px;
        top: 10px;
      }
    }

    @media (max-width: 480px) {
      header {
        padding: 30px 10px;
      }

      header h1 {
        font-size: 1.7rem;
      }

      header p {
        font-size: 0.95rem;
      }

      nav a {
        font-size: 0.95rem;
      }

      h2 {
        font-size: 1.25rem;
      }

      p, li {
        font-size: 0.95rem;
      }

      .footer {
        font-size: 0.75rem;
        padding: 8px;
      }

      .popup-content {
        width: 98%;
        height: 98%;
        margin: 1% auto;
        border-radius: 8px;
      }

      .popup-close {
        width: 35px;
        height: 35px;
        font-size: 24px;
        right: 8px;
        top: 8px;
      }
    }