body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  color: white;
}

.content {
  position: fixed;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  color: #f1f1f1;
  width: 100%;
  padding: 10px;
}

.topnav {
  overflow: hidden;
  background-color: #333;
}

.topnav a {
  float: left;
  display: block;
  color: #f2f2f2;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  font-size: 17px;
}

.topnav a:hover {
  background-color: #781176;
  color: white;
}

.topnav a.active {
  background-color: #781176;
  color: white;
}

.topnav .icon {
  display: none;
}

 #leftbox {
            float: left;
            border-radius: 25px;
            /*background: grey;*/
            background-color: rgba(102, 102, 100, 0.2);
            width: 65%;
            height: 400px;
            padding: 10px; 
        }
 
        #middlebox {
            float: left;
            border-radius: 25px;
            background: Green;
            width: 50%;
            height: 280px;
            padding: 20px; 
        }
 
        #rightbox {
            float: right;
            border-radius: 25px;
            /*background: #666699;*/
            background-color: rgba(102, 102, 153, 0.2);
            width: 25%;
            height: 400px;
            padding: 10px; 
        }


#myVideo {
  width: 100vw;
   height: 100vh;
   object-fit: cover;
   position: fixed;
   left: 0;
   right: 0;
   top: 0;
   bottom: 0;
   z-index: -1;
}

@media screen and (max-width: 600px) {
  .topnav a:not(:first-child) {display: none;}
  .topnav a.icon {
    float: right;
    display: block;
  }
}

@media screen and (max-width: 600px) {
  .topnav.responsive {position: relative;}
  .topnav.responsive .icon {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a {
    float: none;
    display: block;
    text-align: left;
  }
}


.box {
    
                float: left;
            border-radius: 25px;
            /*background: grey;*/
            background-color: rgba(102, 102, 100, 0.2);
            width: 65%;
            height: 400px;
            padding: 10px; 
    
    
    
    
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 10px;
  height: 400px;
  width: 65%;
  border: 400px solid #0000;
  border-radius: 12px;
  background: linear-gradient(#131219, #131219) padding-box, linear-gradient(
        var(--angle),
        #070707,
        #687aff
      ) border-box;
  animation: 4s rotate linear infinite;
}

@keyframes rotate {
  to {
    --angle: 360deg;
  }
}

@property --angle {
  syntax: "<angle>";
  initial-value: 0deg;
  inherits: false;
}