:root {
    --primary-color: #4a90e2;
    --secondary-color: #f5a623;
    --background-color: #f0f2f5;
    --text-color: #333;
    --white: #fff;
}

body {
    font-family: 'Helvetica Neue', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 600px;
    background-color: var(--white);
    border-radius: 12px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    padding: 30px;
    text-align: center;
}

h1 {
    color: var(--primary-color);
    margin-bottom: 30px;
}

.generator {
    margin-bottom: 30px;
}

#generate-btn {
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: 8px;
    padding: 15px 30px;
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

#generate-btn:hover {
    background-color: #357abd;
}

.numbers-display {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-top: 30px;
}

.number-ball {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: var(--secondary-color);
    color: var(--white);
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    font-weight: bold;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.history h2 {
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 10px;
    margin-bottom: 20px;
}

#history-list {
    list-style: none;
    padding: 0;
    margin: 0;
    max-height: 200px;
    overflow-y: auto;
}

#history-list li {
    background-color: #f9f9f9;
    padding: 10px;
    border-radius: 5px;
    margin-bottom: 10px;
    font-size: 16px;
}