* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: system-ui, sans-serif;
      background: #f5f5f5;
    }

    .main_top{
      
    }

    .top__header--menu a  {
      color: rgb(255, 0, 0);    
      padding: 5px;  
      left: 100px;  
      font-weight: 500px;
      letter-spacing: 0.2px;
      text-decoration: none;
      display: block;
      position:fixed;
      top: 20px;
      z-index: 1000;
      
}

    .gallery-header {
      padding: 20px;
      text-align: center;
      background: white;
      color:rgb(81, 255, 0);
      position: sticky;
      font-size:30px;
      top: 0;
      z-index: 999;
      opacity: 999;
      box-shadow: 15px 15px 25px rgb(255, 0, 0);
    }

    .image-grid {
      display: grid;
      grid-template-rows:repeat(3, 1fr); 
      gap: 20px;
      /*padding: 10px;
      margin: 15px;  */
      }
      
    .image-item {
      width: 400px;
      height: 325px;
      cursor: pointer;
    }

  

    /* Мобильные устройства */
    @media (max-width: 768px) {
      .image-grid {
        grid-template-columns: repeat(1, 1fr);
        gap: 10px;
        padding: 10px;
      }
      .gallery-header{
        font-size:20PX;
        width: 400px;
        margin: 20px;
        align-content: center;
      }
    }
    @media (min-width: 440px) {
      .image-grid {
        grid-template-columns: repeat(1, 1fr);
        gap: 10px;
        padding: 10px;
      }
    }

    /* Планшеты */
    @media (min-width: 769px) and (max-width: 1024px) {
      .image-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    /* Десктопы */
    @media (min-width: 1025px) {
      .image-grid {
        grid-template-columns: repeat(3, 1fr);
      }
    }

    /* Большие экраны */
    @media (min-width: 1600px) {
      .image-grid {
        grid-template-columns: repeat(3, 1fr);
      }
      .gallery-header{
        font-size: 60px;
      }
      .top__header--menu{
        font-size: 60px;
      }
    }