:root {
    --bg-color: #ffffff;
    --surface-color: #f3f4f6;
    --text-primary: #111827;
    --text-secondary: #4b5563;
    --accent-color: #2563eb;
    /* Stronger Blue for light mode */
    --accent-hover: #1d4ed8;
    --border-color: #e5e7eb;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --max-width: 1000px;
}

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

body {
    font-family: var(--font-sans);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* Layout */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* Typography */
h1,
h2,
h3 {
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2rem;
    font-weight: 600;
}

a {
    color: inherit;
    text-decoration: none;
    transition: 0.2s;
}

a:hover {
    color: var(--accent-color);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    background-color: var(--accent-color);
    color: white;
    font-weight: 600;
    border-radius: 50px;
    text-decoration: none;
    transition: all 0.3s ease;
    border: 1px solid transparent;
}

.btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.3);
    color: white;
}

.btn-secondary {
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.btn-secondary:hover {
    border-color: var(--text-primary);
    color: var(--text-primary);
    background-color: var(--surface-color);
}

/* Cards */
.card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 30px;
    transition: 0.3s;
}

.card:hover {
    border-color: var(--accent-color);
}


.card h2 {
    font-size: 1.5rem;
    border-bottom: none;
    margin-bottom: 15px;
    display: block;
}

/* Footer */
footer {
    text-align: center;
    padding: 60px 0;
    margin-top: 60px;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Utilities */
.btn {
    display: inline-block;
    background-color: var(--accent-color);
    color: white;
    padding: 12px 30px;
    border-radius: 30px;
    font-weight: 600;
    transition: background-color 0.2s;
}

.btn:hover {
    background-color: var(--accent-hover);
    text-decoration: none;
}

/* Responsive */
@media (max-width: 600px) {
    h1 {
        font-size: 2.2rem;
    }

    .hero {
        padding: 60px 0;
    }

    .card {
        padding: 20px;
    }
}