* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Arial', sans-serif;
}

body {
    background-color: #f0f2f5;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    background-color: white;
    border-radius: 10px;
    padding: 2rem;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 600px;
}

h1 {
    text-align: center;
    color: #1a1a1a;
    margin-bottom: 2rem;
}

.categories {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-bottom: 2rem;
}

.category-btn {
    padding: 0.8rem;
    border: 2px solid #e0e0e0;
    background-color: white;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: bold;
}

.category-btn:hover {
    background-color: #f0f2f5;
}

.category-btn.active {
    background-color: #4a90e2;
    color: white;
    border-color: #4a90e2;
}

.generate-btn {
    width: 100%;
    padding: 1rem;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: bold;
    margin-bottom: 1rem;
    transition: background-color 0.3s ease;
}

.generate-btn:hover {
    background-color: #45a049;
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    margin-top: 1rem;
}

.result-item {
    background-color: #f8f9fa;
    padding: 0.8rem;
    border-radius: 5px;
    text-align: center;
    font-weight: bold;
    border: 1px solid #e0e0e0;
}

.number-select {
    margin-bottom: 1rem;
    text-align: right;
}

.number-select select {
    padding: 0.5rem;
    border-radius: 5px;
    border: 1px solid #e0e0e0;
}

.github-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background-color: #24292e;
    color: white;
    border: none;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    transition: background-color 0.3s ease;
}

.github-btn:hover {
    background-color: #1a1f24;
}

.footer {
    text-align: center;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid #e0e0e0;
    color: #666;
    font-size: 0.9rem;
}

.footer a.link {
    color: #1384cf;
    text-decoration: none;
}