*  {
    padding: 0;
    margin: 0%;
    text-decoration: none;
    box-sizing: border-box;
    font-family: 'Sarabun', Arial, sans-serif;
}



header {
    background-color: #1a458a;
    background-size: cover;
    border-bottom: 5px solid #ffc726;
    margin-bottom: 50px;
}

.responsive {
    max-width: 20%;
    height: auto;
    margin-top: 20px;
    margin-bottom: 20px;
    padding-left: 20px;
  }




img{
    width: 100%;
    height: 100%;
}



.page-container{
    position: absolute;
    perspective: 2048px;
    right: 8%;
}

.center-page {
    position: absolute;
    left: 50%;
    top: 60%;
    transform: translate(-50%, -50%);
    }
    iframe {
    border: 0;
    }

.page{
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    transform-style: preserve-3d;
    color: white;
}

.front, .back{
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
}


.next-btn{
    position: absolute;
    bottom: 13px;
    right: 13px;
    cursor: pointer;
    color: white;
    font-weight: 600;
}

.back-btn{
    position: absolute;
    bottom: 13px;
    left: 13px;
    cursor: pointer;
    color: white;
    font-weight: 600;
}

button {
    background-color: lightcoral;
    border-radius: 50%;
    color: #fff;
    padding: 12px 32px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 14px;
    margin: 4px 2px;
    cursor: pointer;
}

button i{
    color: #fff;
}

button:hover i{
    color: #fff;
}

footer {
    text-align: left;
    padding: 50px;
    margin-top: 50px;
    background-color: #1A458A;
    border-top: 5px solid #ffc726;
    color: white;
}