:root {
    --primary: #4a6bff;
    --dark: #1e293b;
    --light: #f8fafc;
    --gray: #64748b;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background: #fff;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--primary);
}

nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

nav a {
    text-decoration: none;
    color: var(--gray);
    font-weight: 500;
    transition: color 0.3s;
}

nav a.active {
    color: var(--primary);
}

.mobile-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
}

.hero {
    padding: 5rem 0;
    background: linear-gradient(135deg, #f5f7ff 0%, #f8fafc 100%);
}

.hero-content {
    max-width: 600px;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero p {
    font-size: 1.2rem;
    color: var(--gray);
    margin-bottom: 2rem;
}

.btn {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    background: var(--primary);
    color: white;
    border-radius: 0.3rem;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(74, 107, 255, 0.3);
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
}

.card {
    background: #fff;
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s;
}

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

.card i {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 1rem;
}

.content-image {
    width: 100%;
    max-width: 500px;
    margin: 2rem auto;
    display: block;
}

.concepts {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
}

.concepts div {
    background: #f8fafc;
    padding: 1.5rem;
    border-radius: 0.5rem;
}

pre {
    background: #1e293b;
    color: #f8fafc;
    padding: 1rem;
    border-radius: 0.5rem;
    overflow-x: auto;
    margin: 1rem 0;
}

.flow-steps {
    margin: 2rem 0;
    padding-left: 1.5rem;
}

.flow-steps li {
    margin-bottom: 1rem;
}

footer {
    background: var(--dark);
    color: white;
    padding: 2rem 0;
    text-align: center;
    margin-top: 3rem;
}

@media (max-width: 768px) {
    nav {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: white;
        padding: 1rem;
        box-shadow: 0 5px 10px rgba(0,0,0,0.1);
        transform: translateY(-150%);
        transition: transform 0.3s;
    }

    nav.active {
        transform: translateY(0);
    }

    nav ul {
        flex-direction: column;
        gap: 1rem;
    }

    .mobile-toggle {
        display: block;
    }

    .hero {
        text-align: center;
    }
}