style.css

/* GLOBAL */
*{
    box-sizing: border-box;
}
html{
    scroll-behavior: smooth;
}
body{
    margin: 0px;
    background-color: rgb(191, 224, 199);
    padding: 0px ;

}

.nav, .main, .footer{
    margin:0px auto;
        
}



/* GLOBAL END */

/* NAV START */
.nav{
    height: 100px;
    background-color:rgb(14, 75, 90) ;
    width: 80%;
    top:0px;
    left: 10%;
    position:fixed;
    z-index: 1;
    display: block;
    
}
.logo{
    margin:0px 0px 0px 30px;
    padding:0px;
    float: left;
    
}
.logo h1{
    padding: 0px;
    color:white;
}
.menu{
    float: right;
    margin-top:20px;
}
.menu ul li{
    list-style: none;
    display: inline;

}
.menu ul li:not(:last-child){
    margin-right: 50px;
}
.menu ul li:last-child{
    margin-right: 20px;
}
.menu ul li a{
    text-decoration: none;
    position:relative;
    transition: all .35s ease;
    color:aquamarine;
}
.menu ul li a:hover::after{
    content: ""; 
    position: absolute;
    width: 100%;
    height: 2px;
    bottom: 0;
    left: 0;
    background-color: #fff;
    visibility: visible;
    -webkit-transition: all 0.3s ease-in-out 0s; 
    transition: all 0.3s ease-in-out 0s;
    -webkit-transform: scaleX(1);
    transform: scaleX(1);
    top:20px;
}
.menu ul li a:hover{
    color:#fff
}

/* NAV END */


/* MAIN SECTION */ 

.main{
    background-color: rgb(41, 167, 199);
    width: 80%;
    height: auto;
    position: relative;
    overflow: hidden;
    margin-top: 5.55%;

    
}

/* MAIN SECTION END */ 


/*sidebar */

.sidebar{
    margin:0px 0px;
    width: 15%;
    height: 100vh;
    background-color:  rgb(24, 110, 131);
    position:fixed;
    top:13.5%;
}
.sidebar{
    padding:5px 10px;
}
.sidebar a{
    display: block;
    color: white;
    margin: 20px 0px;
    border:1px solid #fff;
    padding:10px;
    transition: all 0.3s ease-in-out 0s;
    -webkit-transform: scaleX(1);
    transform: scaleX(1);
    text-align: center;
    text-decoration: none;

}

.sidebar a:hover{
    background-color: blue;
}

.sidebar a:visited{
    background-color: rgb(48, 48, 214);
}
.sidebar a:active{
    background-color: rgb(135, 15, 182);
}

/*sidebar end*/

/* content */

.content {
    height: auto;
    width: 81.3%;
    background-color: rgb(31, 138, 165);
    margin-left: 18.7%;
    position: relative;
    padding: 0px;

}
/* Inside content */

.content>div{
    height: 100vh;
    padding: 30% 3%;
    margin: 3% 0;
    width: 100%;

}
.block1{
    background-color: rgb(118 212 134);
}

.block1 button{
    border-radius:50%;
    height: 100px;
    width: 100px;
    font-size:20px;
    border:none;
    background-color: orange;

    transition: all 0.3s ease-in-out 0s;
    position: relative;
}

.block1 button:hover{
    background-color: rgb(255, 115, 0);

}



.block1 button:hover:after{
    
    content:'I LOVE YOU';
     /* no need for qoutes */
    color: #fff;
    display: block;
    position: absolute;
    left: 123px; /* change this value to one that suits you */
    top: 0px; 
    background-color: rgb(211, 23, 23);
    height: 100px;
    width: 400px;
    text-align: center;
    vertical-align: middle;
    line-height: 5rem;  
    border-radius: 50px;
    animation-name: example;
    animation-duration: 3s;
    animation-iteration-count: infinite;
  
    
}

@keyframes example {
    from {background-color: rgb(187, 56, 56);}
    to {background-color: rgb(192, 56, 219);}
    25%  { left:200px; top:0px;}
  }


.block2{
    background-color: rgb(216, 94, 89);
    /* display: flex;   */
}


/* block 2 */

.emoji {
    padding: 3rem;
    font-size: 6rem;
    transform: scale(.5);
    text-shadow: 0 2px 4px rgba(0,0,0,.3);
    transition: 
      text-shadow .2s ease-in-out,
      transform .2s ease-in-out;
  }
  
  .emoji:hover {
    transform: scale(1) translatey(-20px);
    text-shadow: 0 20px 20px rgba(0,0,0,.3);
  }
  
  .emoji--happy:before {
    content: '🙂';
  }
  
  .emoji--happy:hover:before {
    content: '😄';
  }
  
  .emoji--sad:before {
    content: '😕';
  }
  
  .emoji--sad:hover:before {
    content: '☹️';
  }
  
  .emoji--crying:before {
    content: '😥';
  }
  
  .emoji--crying:hover:before {
    content: '😰';
  }
  
  .emoji--grimacing:before {
    content: '😬';
  }
  
  .emoji--grimacing:hover:before {
    content: '😁';
  }
/* block 2 end */


.block3{
    background-color: rgb(54, 182, 221);
}

.flag-border{
    height: 15em;
    width: 35em;
    background-color: green;
    position: relative;
    overflow: hidden;
}
.flag-circle{
    height: 10em;
    width: 10em;
    border-radius: 50%;
    background-color: red;
    top: 16%;
    left: 35%;
    position: absolute;

}

/* Inside content end */



/* content end */



/* Footer Section */
.footer{
    height: 100px;
    width:80%;
    background-color:rgb(14, 75, 90) ;
    overflow: hidden;
    z-index: 1;
    position:relative;

}
.footer p{
    color: #fff;
    text-align: center;
    vertical-align: middle;
    line-height: 4rem;  
}
/* Footer END */