* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
html {
    font-size: 62.5%;
}
header {
    display: flex;
    flex-wrap: wrap;
    background-color: #000000;
    padding: 2rem;
    font-family: 'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif;
    color: #fff;
    justify-content: space-evenly;
}
body{
    background-color: #000000;
}
h1 {
    display: inline-block;
    font-size: 4.8rem;
}

nav ul li {
    padding-top: 1.5rem;
    font-size: 2rem;
    font-family: 'Gill Sans', 'Gill Sans MT', Calibri, 'Trebuchet MS', sans-serif;
    display: inline-block;
    justify-content:flex-end;
    margin-left: 2.5rem;
}

main {
    display: flex;
    flex-wrap: wrap;
    flex-direction: row;
    justify-content: space-around;
}

div {
    background-color: white;
    height: 15rem;
    width: 30rem;
    padding: 2rem;
    border: 1px solid  rgb(255, 255, 255);
    border-radius: 2rem;
    margin: 2rem;
    opacity: 0.6;
    text-align: center;
    line-height: 2 rem;
    font-size: 2.5rem;
    font-weight: bold;
    box-shadow: 10px 10px 10px #aaa;
}

div:hover {
    opacity: 1.0;
    transform: rotate(-1deg) scale(1.1);
}
.InsjQueryElements {
    background-image: url(./assets/InsJQueryElements.PNG);
    background-size:130px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StujQueryElements {
    background-image: url(./assets/StujQueryElements.PNG);
    background-size:200px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsClickEvents {
    background-image: url(./assets/InsClickEvents.PNG);
    background-size:80px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuClickEvents {
    background-image: url(./assets/StuClickEvents.PNG);
    background-size:120px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsFormElements {
    background-image: url(./assets/InsFormElements.PNG);
    background-size:120px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuFormElements {
    background-image: url(./assets/StuFormElements.PNG);
    background-size:160px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsDomTraversal {
    background-image: url(./assets/InsDomTraversal.PNG);
    background-size:100px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuDomTraversal {
    background-image: url(./assets/StuDomTraversal.PNG);
    background-size:80px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsEventDelegation {
    background-image: url(./assets/InsEventDelegation.PNG);
    background-size:80px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuEventDelegation {
    background-image: url(./assets/StuEventDelegation.PNG);
    background-size:80px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsBootstrapComponents {
    background-image: url(./assets/InsBootstrapComponents.PNG);
    background-size:200px 60px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuBootstrapComponents {
    background-image: url(./assets/StuBootstrapComponents.PNG);
    background-size:200px 50px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsBootstrapLayout {
    background-image: url(./assets/InsBootstrapLayout.PNG);
    background-size:200px 40px;;
    background-repeat: no-repeat;
    background-position:bottom;   
}

.StuBootstrapLayout {
    background-image: url(./assets/StuBootstrapLayouts.PNG);
    background-size:200px 70px;;
    background-repeat: no-repeat;
    background-position:bottom;   
}

.InsBootstrapUtilities {
    background-image: url(./assets/InsBootstrapUtilities.PNG);
    background-size:200px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;  
}

.StuBootstrapUtilities {
    background-image: url(./assets/StuBootstrapUtilities.PNG);
    background-size:60px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsBootstrapExtended {
    background-image: url(./assets/InsBootstrapExtended.PNG);
    background-size:150px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuBootstrapExtended {
    background-image: url(./assets/StuBootstrapExtend.PNG);
    background-size:150px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsGoogleFonts {
    background-image: url(./assets/InsGoogleFonts.PNG);
    background-size:150px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuGoogleFonts {
    background-image: url(./assets/StuGoogleFonts.PNG);
    background-size:200px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsJQueryUIWidgets {
    background-image: url(./assets/InsJQueryUIWidgets.PNG);
    background-size:100px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuJQueryWidgets {
    background-image: url(./assets/StuJQueryUIWidgets.PNG);
    background-size:200px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsJQueryUIInteraction {
    background-image: url(./assets/InsJQueryUIInteraction.PNG);
    background-size:70px 70px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuJQueryUIInteraction {
    background-image: url(./assets/StuJQueryUIInteraction.PNG);
    background-size:150px 70px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.InsMomentFormat {
    background-image: url(./assets/InsMomentFormat2.PNG);
    background-size:100px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuMomentFormat {
    background-image: url(./assets/StuMomentFormat.PNG);
    background-size:100px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.StuMiniProject {
    background-image: url(./assets/StuMiniProject.PNG);
    background-size:100px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

.Homework {
    background-image: url(./assets/Homework.PNG);
    background-size:150px 90px;;
    background-repeat: no-repeat;
    background-position:bottom;
}

/* Dark mide Switch */
.switch {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
  }
  
  /* Hide default HTML checkbox */
  .switch input {
    opacity: 0;
    width: 0;
    height: 0;
  }
  
  /* The slider */
  .slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ff0000;
    -webkit-transition: .4s;
    transition: .4s;
  }
  
  .slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: rgb(255, 255, 255);
    -webkit-transition: .4s;
    transition: .4s;
  }
  
  input:checked + .slider {
    background-color: rgb(0, 255, 0);
  }
  
  input:focus + .slider {
    box-shadow: 0 0 1px rgb(29, 128, 210);
  }
  
  input:checked + .slider:before {
    -webkit-transform: translateX(26px);
    -ms-transform: translateX(26px);
    transform: translateX(26px);
  }
  
  /* Rounded sliders */
  .slider.round {
    border-radius: 34px;
  }
  
  .slider.round:before {
    border-radius: 50%;
  }
  
  .row {
    margin: 20px;
    display: flex;
  }
  .col {
    margin: 20px;
  }
  /* Dark mide Switch */