* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}


body {
    font-family: 'Poppins', sans-serif;
    background-color: #f4f4f9;
    color: #333;
    background-image: url(image/uni_bg_img.png);
    background-size: cover;
    background-attachment: fixed;
    overflow-x: hidden;
}


nav {
    background-color: #2C3E50;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
    padding: 0 50px;
    position: sticky;
    top: 0;
    z-index: 10;
}

nav .nav-logo img {
    height: 50px;
    width: 50px;
}

.nav-opt ul {
    display: flex;
    list-style: none;
    transition: 0.5s;
}

.nav-opt ul li {
    margin-left: 30px;
}

.nav-opt ul li a {
    text-decoration: none;
    color: #ecf0f1;
    font-size: 18px;
    padding: 10px;
    transition: all 0.3s ease;
    position: relative;
}

.nav-opt ul li a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 3px;
    background: #3498db;
    left: 0;
    bottom: 0;
    transition: width 0.4s ease;
}

.nav-opt ul li a:hover::after {
    width: 100%;
}

.nav-opt ul li a:hover {
    color: #3498db;
}

.burger {
    display: none; 
    font-size: 30px;
    cursor: pointer;
    color: #ecf0f1;
    padding: 10px;
}

.introduction {
    text-align: center;
    padding: 100px 20px;
    background-color: rgba(0, 0, 0, 0.7);
    color: #fff;
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.intro-heading h1 {
    font-size: 50px;
    margin-bottom: 20px;
    animation: fadeInDown 1s ease;
}

.intro-heading span {
    color: #e67e22;
}

.sub-head h3 {
    font-size: 24px;
    margin-bottom: 40px;
    animation: fadeInUp 1.5s ease;
}

.intro-boxes {
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
}

.get-started-box-client, .get-started-box-engineer {
    background-color: #ecf0f1;
    width: 400px;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s;
}

.get-started-box-client:hover, .get-started-box-engineer:hover {
    transform: translateY(-10px);
}

.client-box-heading, .engineer-box-heading {
    text-align: center;
    font-size: 24px;
    color: #2C3E50;
    margin-bottom: 20px;
}

input[type="text"], input[type="email"] {
    width: 100%;
    padding: 10px;
    border-radius: 8px;
    border: 2px solid #bdc3c7;
    font-size: 16px;
    margin-top: 10px;
    transition: border-color 0.3s;
}

input[type="text"]:focus, input[type="email"]:focus {
    border-color: #3498db;
}

input[type="submit"] {
    margin-top: 20px;
    background-color: #3498db;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
}

input[type="submit"]:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 1024px) {
    nav ul li {
        margin-left: 15px;
    }

    .intro-heading h1 {
        font-size: 35px;
    }

    .sub-head h3 {
        font-size: 18px;
    }

    .get-started-box-client, .get-started-box-engineer {
        width: 80%;
    }
}

@media (max-width: 768px) {
    .burger {
        display: block;
    }

    .nav-opt ul {
        position: absolute;
        top: 80px;
        left: -100%; 
        background: #2C3E50;
        width: 100%;
        flex-direction: column;
        align-items: center;
        z-index: 1000;
    }

    .nav-opt ul.active {
        left: 0;
    }

    nav ul li {
        margin: 15px 0;
    }

    .intro-heading h1 {
        font-size: 30px;
    }

    .sub-head h3 {
        font-size: 16px;
    }

    .get-started-box-client, .get-started-box-engineer {
        width: 90%;
    }
}

@media (max-width: 576px) {
    nav ul li {
        margin-left: 5px;
    }

    .intro-heading h1 {
        font-size: 24px;
    }

    .sub-head h3 {
        font-size: 14px;
    }

    .nav-opt ul li a {
        font-size: 16px;
    }

    .intro-boxes {
        flex-direction: column;
    }

    input[type="text"], input[type="email"] {
        width: 95%;
        font-size: 12px;
    }

    input[type="submit"] {
        width: 100%;
        font-size: 14px;
    }
}