<div class="sea">
    <div class="circle-wrapper">
        <div class="bubble"></div>
        <div class="submarine-wrapper">
            <div class="submarine-body">
                <div class="window"></div>
                <div class="engine"></div>
                <div class="light"></div>
            </div>
            <div class="helix"></div>
            <div class="hat">
              <div class="leds-wrapper">
                  <div class="periscope"></div>
                  <div class="leds"></div>
              </div>
            </div>
        </div>
    </div>
</div>




<!-- Link to my website -->
<a id="ajerez" href="http://www.ajerez.es/en/" target="_blank"><img src="https://i.imgur.com/AI4BS2I.png"/></a>


$color1: #306D85;
$color2: #D93A54;

body {
    background-color: $color1;
    

}

*, *:before, *:after {
    box-sizing: border-box;
}


.sea {
    margin: 40px auto 0 auto;
    overflow: hidden;
    
    .bubble {
        position: absolute;
        width: 7px;
        height: 7px;
        border-radius: 50%;
        background-color: lighten($color1, 25%);
        opacity: 0.9;
        animation: bubble1-h-movement 1s ease-in infinite, bubble1-v-movement 300ms ease-in-out infinite alternate, bubble-scale-movement 300ms ease-in-out infinite alternate;
        
        &:after {
            position: absolute;
            content: "";
            width: 7px;
            height: 7px;
            border-radius: 50%;
            background-color: lighten($color1, 25%);
            opacity: 0.9;
            
        }
        &:after {
          top: -20;
          left:100px;
          width: 9px;
          height: 9px;
        }
        

    }
    
    .circle-wrapper {
        position: relative;
        background: linear-gradient(darken($color1, 3%), darken($color1, 12%));
        width:300px;
        height:300px;
        margin: 10px auto 0 auto;
        overflow: hidden;
        z-index: 0;
        border-radius:50%;
        padding: 0 50px 0 50px;
        border: 6px solid lighten($color1, 10%);
        
    }
    
    .submarine-wrapper {
        height: 300px;
        width: 300px;
        padding: 30px 50px 30px 150px;
        margin: 0 auto 0 auto;
        animation: diving 3s ease-in-out infinite, diving-rotate 3s ease-in-out infinite;
        
       .submarine-body {
           
           width: 150px;
           height: 80px;
           position: absolute;
           margin-top: 50px;
           left: 25px;
           background-color: $color2;
           border-radius: 40px;
           background: linear-gradient($color2, darken($color2, 10%));
           
           .light {
                position:absolute;
                width: 0;
                height: 0;
                border-style: solid;
                border-width: 0 40px 150px 40px;
                border-color: transparent transparent lighten($color1,5%) transparent;
               
                transform: rotate(-50deg);
               top:40px;
               left:99%;
               
               &:after {
                   content:"";
                   position: absolute;
                   width: 20px;
                   height:13px;
                   border-radius:5px;
                   background-color:darken($color2, 5%);
                   margin-left:-10px;
               }

           }
           
           .window {
               width: 37px;
               height: 37px;
               position: absolute;
               margin-top: 23px;
               right: 18px;
               background: linear-gradient(darken($color1, 13%), darken($color1, 18%));
               border-radius: 50%;
               border: 3px solid $color2;
               
                &:after {
                  content: "";
                  position: absolute;
                  margin-top:3px;
                  margin-left:3px;
                  width: 25px;
                  height: 25px;
                  border-radius: 50%;
                  background-color: transparent;
                  opacity:0.8;
                  border-top:3px solid white;
                  transform:rotate(-45deg); 
                }
           }
           
           .engine {
               width: 30px;
               height: 30px;
               position: absolute;
               margin-top: 32px;
               left: 53px;
               background-color: darken($color2, 10%);
               border-radius: 50%;
               border: 5px solid $color2;
               
               &:after, &:before {
                  position: absolute;
                  content: "";
                  border-radius: 2px;
                  background-color: white;
                  animation:spin 900ms linear infinite;
                  opacity:0.8;
                }
                &:after {
                  top:8px;
                  width: 20px;
                  height: 4px;
                  
                }
                &:before {
                  left:8px;
                  width: 4px;
                  height: 20px;
                  
                }
           }
       }
       
        .helix {
           width: 30px;
           height: 70px;
           position: absolute;
           margin-top: 55px;
           left:0;
           background-color: $color2;
           border-radius: 7px;
           background: linear-gradient($color2, darken($color2, 10%));
           
            &:after {
                content: "";
                position: absolute;
                margin-top:5px;
                margin-left:7px;
                width: 17px;
                height: 60px;
                border-radius: 3px;
                background-color: transparent;
                opacity:0.8;
                background: linear-gradient(
                  to bottom,
                  $color2,
                  $color2 50%,
                  lighten($color2, 15%) 50%,
                  lighten($color2, 15%)
                );
                background-size: 100% 20px;
                animation:helix-movement 110ms linear infinite;

            }
        }
        
        
        .hat {
           width: 65px;
           height: 25px;
           position: absolute;
           margin-top: 26px;
           left:70px;
           background-color: $color2;
           border-radius: 10px 10px 0 0;
           background: linear-gradient($color2, darken($color2, 3%));
           
            .periscope {
                position: absolute;
                width: 7px;
                height: 20px;
                background-color: $color2;
                margin-top: -27px;
                margin-left:32px;
                border-radius:5px 5px 0 0;
                
                &:after, &:before {
                    content: "";
                    position: absolute;
                    width: 15px;
                    height: 7px;
                    border-radius: 5px;
                    background-color: $color2;
                }
            }
            
            .leds-wrapper {
               width: 53px;
               height: 13px;
               position: relative;
               top:7px;
               left:7px;
               background-color: $color2;
               border-radius: 10px;
               background: linear-gradient(darken($color2, 12%), darken($color2, 16%));
                
                .leds {
                    position: absolute;
                    margin-top:4px;
                    margin-left:7px;
                    width: 5px;
                    height: 5px;
                    border-radius: 50%;
                    background-color: white;
                    animation:leds-off 500ms linear infinite;

                    &:after, &:before {
                        content: "";
                        position: absolute;
                        width: 5px;
                        height: 5px;
                        border-radius: 50%;
                        background-color: white;
                    }
                    &:after {
                        margin-top:0px;
                        margin-left:17px;
                    }
                    &:before {
                        margin-top:0px;
                        margin-left:34px;
                    }
                }
            }
        }
        
        
    }
}


@keyframes spin { 
    100% { 
        transform:rotate(360deg); 
    } 
}

@keyframes leds-off { 
    100% { 
        opacity:0.3;
    } 
}

@keyframes helix-movement {
    100% {
        background: linear-gradient(
          to bottom,
          lighten($color2, 15%) 50%,
          lighten($color2, 15%),
          $color2,
          $color2 50%
        );
        background-size: 100% 20px;
    }
}


@keyframes diving {
	0% {
         margin-top:5px;
	}
    50% {
		 margin-top:15px;
	}
    
    100% {
		 margin-top:5px;
	}
}

@keyframes diving-rotate {
	0% {
         transform:rotate(0deg); 
	}
    50% {
         transform:rotate(3deg); 
	}
    75% {
        transform:rotate(-2deg); 
	}
    100% {
        transform:rotate(0deg); 
	}
}

    @keyframes bubble1-h-movement {
	  0% { 
          margin-left: 80%;
      }
	  100% { 
           margin-left: -100%; 
      }
	}	

    @keyframes bubble2-h-movement {
	  0% { 
          margin-left: 65%;
      }
	  100% { 
           margin-left: -5%; 
      }
	}

	@keyframes bubble1-v-movement {
	  0% { 
          margin-top: 115px; 
      }
	  100% { 
          margin-top:160px; 
      }
	}
    
    @keyframes bubble2-v-movement {
	  0% { 
          margin-top: 115px; 
      }
	  100% { 
          margin-top:90px; 
      }
	}

    @keyframes bubble-scale-movement {
	  0% { 
          transform: scale(1.4);
      }
	  100% { 
          transform: scale(0.9);
      }
	}

    @keyframes light-movement {
	  0% { 
          transform: rotate(-40deg);
      }
      50% {
          transform: rotate(-70deg);
      }
	  100% { 
          transform: rotate(-40deg);
      }
	}

/* Inspiration: http://drbl.in/nOzJ
 * CSS Submarine
 * A pen by Alberto Jerez
 * www.ajerez.es
 */

External CSS

  1. https://codepen.io/ajerez/pen/PqbdWK

External JavaScript

This Pen doesn't use any external JavaScript resources.