body {
    margin: 0;
    font-family: 'Montserrat', Arial, sans-serif;
    background-color: #fff;
    color: #000;
}

header {
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    background: rgba(255, 255, 255, 0.95);
    padding: 1rem 2rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    z-index: 10;
    transform: translateY(-100%);
    transition: transform 0.3s ease;
    display: flex;
    justify-content: center;
}

header .container {
    max-width: 1350px;
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header .logo {
    font-weight: 700;
    font-size: 1.2em;
    letter-spacing: 2px;
}

header nav ul {
    list-style: none;
    display: flex;
    gap: 0.5rem;
    margin: 0;
    padding: 0;
}

header nav ul li a {
    text-decoration: none;
    color: #000;
    padding: 0.4rem 0.8rem;
    transition: background 0.3s ease, color 0.3s ease;
    border-radius: 4px;
    font-size: 0.9rem;
}

header nav ul li a:hover,
header nav ul li a.active {
    background: #000;
    color: #fff;
}

.hero {
    height: 100vh;
    background: url('https://www.tesla.com/sites/default/files/modelsx-new/social/model-x-social.png') center/cover no-repeat;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: #fff;
    position: relative;
}

.hero::after {
    content: "";
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
}

.hero h1 {
    font-size: 3em;
    margin: 0;
}

.hero p {
    font-size: 1.2em;
    margin: 1rem 0;
}

.hero .btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    background: #000;
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    border-radius: 4px;
    transition: background 0.3s ease;
}

.hero .btn:hover {
    background: #333;
}

main {
    padding: 4rem 2rem;
}

.welcome {
    max-width: 1000px;
    margin: 2rem auto;
    text-align: center;
}

.welcome .content {
    font-size: 1.1em;
    line-height: 1.8;
}

.features {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2rem;
    margin: 4rem auto;
    max-width: 1200px;
}

.feature {
    flex: 1 1 300px;
    background: #f9f9f9;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
    text-align: center;
    transition: transform 0.3s ease;
}

.feature:hover {
    transform: translateY(-5px);
}

.feature h3 {
    margin-top: 0;
    font-size: 1.4em;
}

.feature p {
    font-size: 1em;
    line-height: 1.6;
}

.call-to-action {
    text-align: center;
    margin: 4rem auto;
    max-width: 800px;
}

.call-to-action h2 {
    font-size: 2em;
    margin-bottom: 1rem;
}

.call-to-action p {
    font-size: 1.1em;
    margin-bottom: 2rem;
}

.call-to-action .btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    background: #000;
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    border-radius: 4px;
    transition: background 0.3s ease;
}

.call-to-action .btn:hover {
    background: #333;
}

footer {
    text-align: center;
    padding: 2rem;
    background: #f5f5f5;
    color: #666;
    font-size: 0.9em;
}

@media (max-width: 1024px) {
    .hero h1 {
        font-size: 2.5em;
    }
    .hero p {
        font-size: 1.1em;
    }
}

@media (max-width: 768px) {
    header .container {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }

    header nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.5rem;
    }

    .hero {
        height: auto;
        min-height: 60vh;
        padding: 4rem 1rem 2rem;
    }

    .hero-content {
        max-width: 90%;
    }

    .hero h1 {
        font-size: 2em;
    }

    .hero p {
        font-size: 1em;
    }

    .hero .btn {
        padding: 0.8rem 1.8rem;
        font-size: 1em;
    }

    main {
        padding: 2rem 1rem;
    }

    .welcome {
        margin: 1rem auto;
    }

    .welcome .content {
        font-size: 1em;
        line-height: 1.7;
    }

    .features {
        flex-direction: column;
        gap: 1.5rem;
        margin: 2rem auto;
    }

    .feature {
        max-width: 90%;
        margin: 0 auto;
    }

    .call-to-action {
        margin: 2rem auto;
        padding: 0 1rem;
    }

    .call-to-action h2 {
        font-size: 1.6em;
    }

    .call-to-action p {
        font-size: 1em;
    }
}

@media (max-width: 480px) {
    header {
        padding: 0.5rem 1rem;
    }

    header .logo {
        font-size: 1em;
        text-align: center;
    }

    header nav ul li a {
        font-size: 0.85rem;
        padding: 0.3rem 0.6rem;
    }

    .hero {
        padding: 3rem 1rem;
    }

    .hero h1 {
        font-size: 1.6em;
    }

    .hero p {
        font-size: 0.95em;
    }

    .hero .btn {
        font-size: 0.9em;
    }

    .welcome .content {
        font-size: 0.95em;
        text-align: justify;
    }

    .feature h3 {
        font-size: 1.2em;
    }

    .feature p {
        font-size: 0.9em;
    }

    .call-to-action h2 {
        font-size: 1.4em;
    }

    .call-to-action p {
        font-size: 0.95em;
    }

    footer {
        font-size: 0.8em;
        padding: 1rem;
    }
}