body {
    --background-color: #1a1a1a;
    --text-color: #fff;
    --machine-background: #333;
    --number-background: #fff;
    --number-color: #333;
    --button-background: #4CAF50;
    --button-hover-background: #45a049;
    --button-text: #fff;
    --button-shadow: rgba(76, 175, 80, 0.7);
    --button-hover-shadow: rgba(76, 175, 80, 1);
    --panel-shadow: 0 10px 20px rgba(0,0,0,0.19), 0 6px 6px rgba(0,0,0,0.23);

    background-color: var(--background-color);
    color: var(--text-color);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 100 100'%3E%3Cg fill='%23333' fill-opacity='0.1'%3E%3Crect x='0' y='0' width='50' height='50'/%3E%3Crect x='50' y='50' width='50' height='50'/%3E%3C/g%3E%3C/svg%3E");
    transition: background-color 0.3s ease, color 0.3s ease;
}

body[data-theme="light"] {
    --background-color: #f5f7fb;
    --text-color: #1f2937;
    --machine-background: #ffffff;
    --number-background: #1f2937;
    --number-color: #ffffff;
    --button-background: #2563eb;
    --button-hover-background: #1d4ed8;
    --button-shadow: rgba(37, 99, 235, 0.35);
    --button-hover-shadow: rgba(37, 99, 235, 0.55);
    --panel-shadow: 0 10px 20px rgba(15,23,42,0.12), 0 6px 6px rgba(15,23,42,0.08);

    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 100 100'%3E%3Cg fill='%2394a3b8' fill-opacity='0.16'%3E%3Crect x='0' y='0' width='50' height='50'/%3E%3Crect x='50' y='50' width='50' height='50'/%3E%3C/g%3E%3C/svg%3E");
}

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

.header {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

h1 {
    font-size: 3rem;
    margin: 0 0 1rem;
}

.machine {
    background-color: var(--machine-background);
    border-radius: 1rem;
    padding: 2rem;
    margin: 2rem 0;
    box-shadow: var(--panel-shadow);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.numbers {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.number {
    width: 4rem;
    height: 4rem;
    background-color: var(--number-background);
    color: var(--number-color);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    font-weight: bold;
    box-shadow: 0 5px 10px rgba(0,0,0,0.1), 0 3px 3px rgba(0,0,0,0.1);
    transition: background-color 0.3s ease, color 0.3s ease, transform 0.3s ease;
}

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

#generate,
#theme-toggle {
    background-color: var(--button-background);
    color: var(--button-text);
    padding: 1rem 2rem;
    border: none;
    border-radius: 0.5rem;
    font-size: 1.2rem;
    cursor: pointer;
    transition: background-color 0.3s, box-shadow 0.3s;
    box-shadow: 0 0 10px var(--button-shadow);
}

#theme-toggle {
    padding: 0.65rem 1rem;
    font-size: 0.95rem;
    margin-bottom: 1rem;
}

#generate:hover,
#theme-toggle:hover {
    background-color: var(--button-hover-background);
    box-shadow: 0 0 20px var(--button-hover-shadow);
}

@media (max-width: 640px) {
    h1 {
        font-size: 2.2rem;
    }

    .numbers {
        gap: 0.5rem;
        flex-wrap: wrap;
    }

    .number {
        width: 3.2rem;
        height: 3.2rem;
        font-size: 1.6rem;
    }
}