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

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --background: #f8fafc;
    --card-background: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}

header {
    text-align: center;
    margin-bottom: 4rem;
    padding-top: 2rem;
    position: relative;
}

header h1 {
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

header h1 i {
    color: var(--primary-color);
}

.github-link {
    position: absolute;
    top: 2rem;
    right: 0;
    font-size: 2rem;
    color: var(--text-secondary);
    transition: all 0.3s ease;
    text-decoration: none;
}

.github-link:hover {
    color: var(--text-primary);
    transform: scale(1.1);
}

.subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    font-weight: 400;
}

main {
    flex: 1;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

.tool-card {
    background: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
    position: relative;
    display: flex;
    flex-direction: column;
}

.tool-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.tool-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-hover));
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    font-size: 2rem;
    color: white;
}

.tool-card h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.tool-card p {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.5;
    flex: 1;
}

.tool-arrow {
    position: absolute;
    top: 2rem;
    right: 2rem;
    font-size: 1.25rem;
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.tool-card:hover .tool-arrow {
    color: var(--primary-color);
    transform: translateX(4px);
}

footer {
    text-align: center;
    padding: 2rem 0;
    color: var(--text-secondary);
    border-top: 1px solid var(--border-color);
    margin-top: auto;
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    header h1 {
        font-size: 2rem;
    }

    .github-link {
        font-size: 1.5rem;
        top: 1rem;
    }

    .subtitle {
        font-size: 1rem;
    }

    .tools-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .tool-card {
        padding: 1.5rem;
    }
}