*{
    margin: 0;
    padding: 0;
    font-family: "Roboto", sans-serif;
    
}

body{
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    background-image: url(./image/bg.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
    user-select: none;
    height: 100vh;
    width: 100vw;
}

nav{
    top: 0;
    height: 70px;
    width: 100%;
    position: fixed;
    border-bottom: 1px solid black;
}

.logo {
    cursor: pointer;
    float: left;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    height: 70px;
    width: 300px;

}
.sonu{
    height: 70px;
    width: 300px;
    font-size: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    float: right;

    
}

.sonu a{
    
    text-decoration: none;
    color: black;
    margin: 0px 5px;
    cursor: pointer;

    position: relative;
}


a::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: crimson; 
    transition: width 0.4s ease; 
}

a:hover::before {
    width: 100%;
}


@keyframes underlineAnimation {
    0% {
        width: 0;
        left: 0;
    }
    50% {
        width: 100%;
        left: 0;
    }
    100% {
        width: 0;
        left: 0;
    }
}

.animated-underline {
    display: inline-block;
    animation: underlineAnimation 2s infinite;
}


#heart {
    animation: beat 1s infinite ease-in-out;
}

@keyframes beat {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.2); 
    }
}


.fan{
    position: fixed;
    top: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 400px;
    width: 400px;
    background-repeat: no-repeat;
    background-size: cover;
    background-image: url(./image/fan.png);
    transition: transform 0.5s ease;

}

#btn{
    position: fixed;
    border: none;
    cursor: pointer;
    color: black;   
    background-color: rgb(79, 231, 170);
    height: 50px;
    width: 150px;
    font-size: 25px;
    margin-top: 470px;
    border-radius: 30px;
    
}


@media screen and (max-width: 600px){
    .logo{
        width: 120px;
        font-size: 12px;
        justify-content: start;
        padding-left: 20px;

    }
    .sonu{
        width: 230px;
        font-size: 18px;
        justify-content: end;
        padding-right: 30px;
    }
    .fan{
        width: 350px;
        height: 350px;
    }
    #btn{
        width: 150px;
        height: 50px;
        font-size: 25px;
        font-weight: bolder;
        margin-top: 250px;
    }
}


@media screen and (max-width: 400px){
    .logo{
        width: 170px;
        font-size: 12px;
        font-weight: bold;
        justify-content: start;
        padding-left: 20px;

    }
    .sonu{
        width: 180px;
        font-size: 15px;
        justify-content: end;
        padding-right: 10px;


    }

    #heart{
        height: 18px;
    }
    .fan{
        width: 300px;
        height: 300px;
    }
    #btn{
        width: 150px;
        height: 50px;
        font-size: 25px;
        font-weight: bolder;
        margin-top: 150px;
    }
}