*{ /* removing browsers default margin , padding*/
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body{
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background-color: black;
    color: #e7e7e7; /*lightgray = #e7e7e7*/
    min-height: 100vh;
    line-height: 1.5;
}

.image_gradient{
    position: absolute; 
    top:  0;
    right: o;
    opacity: 0.5;
    z-index: -1;
}

.layer_blur{
    height: 0;
    width: 30rem;
    position: absolute;
    top: 20%;
    right: 0;
    box-shadow:0 0 700px 15px white ;
    rotate: -30deg;
    z-index: -1;
}


.container{    
    width: 100%;
    margin: 0 auto; /*making it center*/ /* margin : top_bottom left_right */
    padding: 0 2rem; 
    position: relative;
    overflow: hidden;
}

header{
    display: flex; /*to align elements horizontaly*/
    justify-content: space-between; /*to push the logo and navigation links horizontal */
    align-items: center;
    padding: 1rem 5rem;
    
}

header h1{
    margin: 0;
    font-size: 2rem;
    font-weight: 400;
}

nav{
    display: flex;
    align-items: center;
    gap: 3rem; /*gap between links */
    margin-left: -5%;    
}

nav a {
    font-size: 1rem;
    letter-spacing: 0.1rem;
    transition: color 0.3s ease;
    text-decoration: none;
    color: inherit;
    z-index: 999; 
}

nav a:hover{
    color: #a7a7a7;
}

.btn_sin{
    background-color: #a7a7a7;
    color: black;
    padding: 0.8rem 1rem;
    font-size: .8rem;
    font-weight: 700;
    border: none;
    border-radius: .5rem;
    transition: background-color 0.3s ease;
    cursor: pointer;
    z-index: 999; 
}

.btn_sin:hover{
    background-color: white;
}


/*MAIN CONTENT*/
main{
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: calc(90vh - 6rem);
}

.content{
    max-width: 40rem;
    margin-left: 10%;
    z-index: 999;
}

.tag_box {
    position: relative;
    width: 18rem;
    height: 2.5rem;
    border-radius: 50px;
    background: linear-gradient(to right,
    #4a148c,
    #6a1b9a,
    #7b1fa2,
    #8e24aa,
    #6a1b9a,
    #4a148c);

    background-size: 200%;
    animation: animationGradient 2.5s linear infinite;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.3);
}

@keyframes animationGradient {
    to {
        background-position: 200%;
    }    
}


.tag_box .tag{
    position: absolute;
    inset: 3px 3px 3px 3px;
    background-color: black;
    border-radius: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: 0.5s ease;
    cursor: pointer;
}


.tag_box .tag:hover{
    color: #5300a0;
}


.content h1{
    font-size: 4rem;
    font-weight: 600;
    letter-spacing: 0.1rem;
    margin: 2rem 0;
    line-height: 1.2;
    text-shadow: 0 0 10px gray;
}

.description{
    font-size: 1.2rem;
    letter-spacing: 0.05em ;
    max-width: 35rem;
    color: gray;
}

.btns{
    display: flex;
    gap: 1rem;
    margin-top: 3rem;

}

.btn_get_started{
    text-decoration: none;
    border: 1px solid #2a2a2a;
    padding: 0.8rem 1.2rem;
    border-radius: 20px;
    font-size: 1.2rem;
    color: #6a1b9a;
    font-weight: 600;
    letter-spacing: 0.1rem;
    transition: background-color .5s  ease;
}

.btn_get_started:hover{
    background-color: #2a2a2a;
    color: white;
}


.btn_sigining_main{
    text-decoration: none;
    background-color: lightgray;
    color: black;
    padding: 0.7rem 2rem;
    border-radius: 20px;
    font-size: 1.2rem;
    font-weight: 600;
    letter-spacing: 0.1rem;
    border: none;
    transition: background-color 0.5s ease;
}

.btn_sigining_main:hover{
    background-color: #6f18f1;
    color: white;
}


.btn_get_started,
.btn_sigining_main {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}



.robot_3d{
    position: absolute;
    top: 0;
    right: -20%;
}

/*Tablet responsive*/
@media (max-width: 1300px) {
    header{
        padding: 1rem 0.5rem;
    }

    .content{
        margin-top: 85%;
    }

    .robot_3d{
        scale:  0.8;
        top: -20%;
        right: 2%;
    }
}

/*mobile responsive*/
@media (max-width: 768px) {
    body {
        overflow-x: hidden;
    }
    header{
        padding: 1rem 0.1rem;
    }
    
    nav{
        display: none;
    }
    
    header h1{
        font-size: 1.9rem;
    }

    .btn_sin{
        padding: 0.6rem 1.5rem;
    }

    .robot_3d{
        scale: 0.45;
        top: -25%;
        right: 0;
    }


    .content{
        max-width: 30rem;
        margin-left: 10%;
    }

    .tag_box{
        width: 12rem;
    }

    .content h1{
        font-size: 2rem;
    }

    .description{
        font-size: 0.8rem;
    }

    .btn_get_started{
        font-size: 0.7rem;
        padding: 0.5rem 1.2rem;
    }
    .btn_sigining_main{
        font-size: 0.7rem;
        padding: 0.5rem 2rem;
    }
}

/*
lets add smooth animate on scroll library by this steps 
go to - https://michalsnik.github.io/aos/
click on the github logo then find installation , add styles in <head> link that in html 
and script inside body copy and past that in html
*/