body {
  background: #000 url(images/bg-website.jpg) center top no-repeat;
  background-size: cover;
  color: #fff;
  font-family: "Kanit", sans-serif;
  display: flex;
  flex-direction: column !important;
  min-height: 100vh;
  overflow-x: hidden;
}
.main-logo{
  width: 60%;
  max-width: 320px;
  margin: auto;
  margin-bottom: -40px;
}
.main-section{
  min-height: 80vh;
}
footer{
  background: url(images/bg-footer.jpg);
  background-size: 1920px;
  font-size: .9em;
}
.ct-center{
  width: 75%;
  margin: 0 auto;
}
.box-vdo{
  background: url(images/bg-vdo.png) center top no-repeat;
  background-size: 100% ;
  width: 350px;
  max-width: 700px;
  height: auto;
  padding: 20px 5% 0 7%;
  position: relative;
  margin: auto;
  margin-top: -20px;
}
.box-vdo iframe{
  width: 100%;
  height: 200px;
  border-radius: 10px;
  border: 2px solid #6a2d03;
}
.btn-main{
  width: 44%;
  display: inline-block;
}
.btn-download{
  width: 150px;
  display: block;
}
.fixed-menu{
  position: fixed;
  background: url(images/monster1.png) top center no-repeat;
  background-size: 100%;
  width: 100px;
  padding-top: 50px;
  right: 3%;
  top: 25%;
  z-index: 100;
  -webkit-animation: action 1s infinite  alternate;
  animation: action 1s infinite  alternate;
}


@media (min-width: 500px){
  .main-logo{
    width: 50%;
    max-width: 320px;
    margin: auto;
    margin-bottom: -50px;
  }
  .box-vdo{
    width:540px;
    max-width: 560px;
    height: auto;
    padding: 39px 7% 50px 8%;
    margin: 0 auto;
    margin-top:-10px;
  }
  .box-vdo iframe{
    width: 100%;
    height: 255px;
  }
  .btn-main{
    width: 160px;
  }
}
@media (min-width: 768px) {
  .main-logo{
    width: 300px;
    max-width: 320px;
    margin: auto;
    margin-bottom: 40px;
  }
  .box-vdo{
    width: 570px;
    max-width: auto;
    padding: 40px 35px 80px 38px;
  }
  .box-vdo iframe{
    width: 100%;
    height: 268px;
    border-radius: 15px;
  }
  .btn-main{
    width: 160px;
  }
  .main-section{
    overflow: hidden;
  }
  .ct-l{
    position: absolute;
    bottom: -105px;
    left: -450px;
    width: 550px;
  }
  .ct-r{
    position: absolute;
    bottom: -105px;
    right: -420px;
    width: 500px;
  }
  footer{
    min-height: 20vh;
    font-size: .9em;
  }
}
@media (min-width: 992px) {  
  .box-vdo{
    width: 700px;
    padding: 50px 40px 76px 49px;
  }
  .box-vdo iframe{
    width: 100%;
    height: 330px;
    border-radius: 15px;
  }
  .btn-main{
    width: 190px;
  }
  .ct-box{
    width: 100%;
    height: 10px;
  }
  .ct-l{
    position: absolute;
    bottom: -105px;
    left: -550px;
    width: 650px;
  }
  .ct-r{
    position: absolute;
    bottom: -105px;
    right: -520px;
    width: 600px;
  }
  footer{
    min-height: 200px;
    font-size: .9em;
  }
  .btn-download {
    width: 220px;
  }
}

@media (min-width: 1200px) {
  .fixed-menu{
    position: fixed;
    background: url(images/monster1.png) top center no-repeat;
    background-size: 100%;
    width: 190px;
    padding-top: 95px;
    right: 3%;
    top: 10%;
    z-index: 100;
    -webkit-animation: action 1s infinite  alternate;
    animation: action 1s infinite  alternate;
  }
  .main-section{
    overflow: hidden;
    min-height: none;
  }
  .box-vdo {
    background: url(images/bg-vdo.png) center no-repeat;
    background-size: 100%;
    width: 90%;
    max-width: 691px;
    height: 509px;
    padding: 46px 40px 86px 43px;
    position: relative; 
  }
  .box-vdo iframe{
    height: 330px;
    border-radius: 20px;
  }
  footer{
    background: url(images/bg-footer.jpg);
    min-height: 170px;
    margin-top: 20px;
  }
  .btn-main{
    width: 200px;
  }
  .ct-l{
    position: absolute;
    bottom: -125px;
    left: -550px;
    width: 650px;
  }
  .ct-r{
    position: absolute;
    bottom: -125px;
    right: -520px;
    width: 600px;
  }
  .btn-download {
    width: 250px;
    display: block;
  }
  .box-btn {
    margin-top: 10px;
  }
}




@-webkit-keyframes action {
  0% { transform: translateY(0); }
  100% { transform: translateY(-10px); }
}

@keyframes action {
  0% { transform: translateY(0); }
  100% { transform: translateY(-10px); }
}