*{
    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: #e7e7e7e7;
    min-height: 100vh;
    line-height: 1.5;
}

.image-gradient{
    position: absolute;
    top: 0;
    right: 0;
    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;
    padding:0 2rem;
    position: relative;
    overflow: hidden;


}
header{
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5rem;
    z-index: 999;
}

header h1{
    margin: 0;
    font-size: 3rem;
    font-weight: 300;

}

nav{
    display: flex;
    align-items: center;
    gap: 3rem;
    margin-left: -5%;
    
}
nav a{
    font-size: 1rem;
    letter-spacing: 0.1rem;
    transition: color 0.2s ease;
    text-decoration: none;
    color: inherit;

}

nav a:hover{
    color: #a7a7a7;
}

.btn-signing{
    background-color: #a7a7a7;
    color: black;
    padding: 0.8rem 2rem;
    border-radius: 50px;
    border: none;
    font-size: 1rem;
    font-weight: 500;
    transition: background-color 0.2s ease;
    cursor: pointer;

}

.btn-signing:hover{
    background-color: white;
}

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

.content{
    max-width: 40rem;
    margin-left: 10%;
    z-index: 999;
    margin-top: 95px;
}

.tag-box{
    position: relative;
    width: 18rem;
    height: 2.5rem;
    border-radius: 50px;
    background: linear-gradient(to right,#656565,#7f42a7,#6600c5,#5300a0,#757575,#656565);
    background-size: 200%;
    animation: animationGradient 2.5s linear infinite;
    box-shadow: 0 0 15px rgba(225,225,225,0.3);
}

@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: 0.5 ease;
    cursor: pointer;
}

.tag-box .tag:hover{
    color: #5300a0;
}

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

}

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

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

.btn-get-started{
    text-decoration: none;
    border: 1px solid #2a2a2a;
    padding: 0.7rem 1.2rem;
    border-radius: 1.2rem;
    font-weight: 600;
    letter-spacing: 0.1rem;
    transition: background-color 0.2s ease;

}

.btn-get-started:hover{
    background-color: #1a1a1a;
}

.btn-signing-main{
    text-decoration: none;
    background-color: lightgray;
    color: black;
    border: 1px solid #2a2a2a;
    padding: 0.7rem 1.2rem;
    border-radius: 1.2rem;
    font-weight: 600;
    letter-spacing: 0.1rem;
    transition: background-color 0.2s ease;

}

.btn-signing-main:hover{
    background-color:bisque;
}

.robot-3d{
    position: absolute;
    top: 0;
    right: -20%;
}
/* =========================
   RESPONSIVE
========================= */

@media (max-width: 1024px){

    header{
        padding: 1rem 2rem;
    }

    .content{
        margin-left: 5%;
    }

    .robot-3d{
    position: absolute;
    top: 0;
    right: -20%;
    width: 600px;
    max-width: 50%;
    height: auto;
}

/* Tablet */
@media (max-width: 1024px){
    .robot-3d{
        right: -30%;
        width: 450px;
        opacity: 0.7;
    }
}

/* Mobile */
@media (max-width: 768px){
    .robot-3d{
        right: -40%;
        width: 350px;
        opacity: 0.5;
    }
}

/* Small Mobile */
@media (max-width: 480px){
    .robot-3d{
        right: -55%;
        width: 280px;
        opacity: 0.4;
    }
}

}

@media (max-width: 768px){

    header{
        flex-direction: column;
        gap: 1.5rem;
        padding: 1.5rem;
        text-align: center;
    }

    nav{
        margin-left: 0;
        gap: 1.5rem;
        flex-wrap: wrap;
        justify-content: center;
    }

    .content{
        margin-left: 0;
        margin-top: 60px;
        text-align: center;
        max-width: 100%;
    }

    .content h1{
        font-size: 2.8rem;
    }

    .description{
        font-size: 1rem;
        max-width: 100%;
    }

    .buttons{
        flex-direction: column;
        align-items: center;
    }

    .tag-box{
        margin: 0 auto;
    }

    .robot-3d{
        display: none; /* mobile এ লুকিয়ে দাও */
    }

}

@media (max-width: 480px){

    header h1{
        font-size: 2rem;
    }

    nav a{
        font-size: 0.8rem;
    }

    .content h1{
        font-size: 2.2rem;
    }

    .btn-signing,
    .btn-get-started,
    .btn-signing-main{
        font-size: 0.8rem;
        padding: 0.6rem 1rem;
    }

}