#header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    transition: background-color 0.4s ease, box-shadow 0.4s ease;
    background-color: transparent;
  }

  /* состояние при скролле */
  #header.scrolled {
    background-color: rgba(255,255,255,0.95);
    box-shadow: 0 2px 12px rgba(0,0,0,0.0);
  }
    #header img {
      max-height: 40px;
    }
  }