:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --text-color: #1f2937;
    --light-bg: #f3f4f6;
    --white: #ffffff;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
}

/* Header & Navigation */
header {
    background: var(--white);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    z-index: 1000;
}

nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

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

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

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

/* Main Content */
main {
    padding-top: 4rem;
}

section {
    padding: 4rem 1rem;
    max-width: 1200px;
    margin: 0 auto;
}

/* Hero Section */
.hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    align-items: center;
    min-height: 80vh;
}

.hero-content h1 {
    font-size: 3rem;
    line-height: 1.2;
    margin-bottom: 1.5rem;
}

.hero-content p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    color: #4b5563;
}

.cta-button {
    display: inline-block;
    background: var(--primary-color);
    color: var(--white);
    padding: 1rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: background-color 0.3s ease;
}

.cta-button:hover {
    background: var(--secondary-color);
}

.hero-image img {
    width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

/* Features Section */
.features {
    background: var(--light-bg);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.feature-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    transition: transform 0.3s ease;
}

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

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

/* How It Works Section */
.steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.step {
    text-align: center;
    padding: 2rem;
}

.step-number {
    width: 40px;
    height: 40px;
    background: var(--primary-color);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
    font-weight: bold;
}

/* Download Section */
.download {
    text-align: center;
    background: var(--light-bg);
}

.download-card {
    background: var(--white);
    padding: 3rem;
    border-radius: 12px;
    max-width: 400px;
    margin: 2rem auto;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.download-card img {
    width: 80px;
    height: 80px;
    margin-bottom: 1.5rem;
}

.download-button {
    display: inline-block;
    background: var(--primary-color);
    color: var(--white);
    padding: 1rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    margin: 1.5rem 0;
    transition: background-color 0.3s ease;
}

.download-button:hover {
    background: var(--secondary-color);
}

.system-req {
    color: #6b7280;
    font-size: 0.875rem;
}

/* Footer */
footer {
    background: #1f2937;
    color: var(--white);
    padding: 4rem 1rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section a {
    color: #9ca3af;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: var(--white);
}

.footer-bottom {
    max-width: 1200px;
    margin: 2rem auto 0;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    text-align: center;
    color: #9ca3af;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content {
        order: 1;
    }

    .hero-image {
        order: 2;
    }

    nav ul {
        gap: 1rem;
    }
}