head{
  background-color: purple;
  color: black;
  width: auto;
  padding: 0%;
  text-align: center;
}
.logo{
  font-family: 'Cinzel', serif;
}
body{
background-color: #f1f1f1;
padding: 0%;
text-align: center;
}
.container-fluid1{
background-image: url(../IMAGES/Mars.jpg);
background-repeat: no-repeat;
background-size: 100%;
}
/*image overlay*/
.image_container {
  position: relative;
  width: 100%;
}

.image {
  display: block;
  width: 100%;
  height: 300px;
}

.overlay {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  height: 100%;
  width: 100%;
  opacity: 0;
  transition: .5s ease;
  background-color: #008CBA;
}

.container:hover .overlay {
  opacity: 1;
}

.text {
  color: red;
  font-size: 20px;
  position: absolute;
  top: 50%;
  left: 50%;
  -webkit-transform: translate(-50%, -50%);
  -ms-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);
  text-align: center;
}
.container1{
  width: 350px;
  float: left;
}
.middle {
  transition: 0s ease;
  opacity: 0;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  -ms-transform: translate(-50%, -50%);
  text-align: center;
}

.container1:hover .image {
  opacity: 0.3;
}

.container1:hover .middle {
  opacity: 1;
}
.text {
  background-color: #4CAF50;
  color: white;
  font-size: 16px;
  padding: 16px 32px;
}
.container2{
  width: 400px;
  float: left;
}
.container3{
  width: 500px;
  height: 800px;
  float: left;
  text-align: center;
}
.container4{
  width: 900px;
  height: auto;
  float: left;
  text-align: center;
}

.footer{
  background-color: #f1f1f1;
  color: #000;
  padding: 0%;
  text-align: center;
  position: auto;
}
 /* Set height of the grid so .sidenav can be 100% (adjust if needed) */
 .row-content {height: 700px}
    
 /* Set gray background color and 100% height */
 .sidenav {
   background-color: #f1f1f1;
   height: 100%;
   padding: 0;
   width: 100px;
 }
 
 /* On small screens, set height to 'auto' for sidenav and grid */
 @media screen and (max-width: 767px) {
   .sidenav {
     height: auto;
     padding: 0;
   }
   .row.content {height: auto;} 
 }