:root {
    --bg-color: #f0f0f0;
    --container-bg: #fff;
    --text-color: #333;
    --shadow-color: rgba(0,0,0,0.1);
    --ball-shadow: rgba(0,0,0,0.2);
    --btn-bg: #4CAF50;
    --btn-hover-bg: #45a049;
    --btn-glow: rgba(76, 175, 80, 0.7);
}

[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --container-bg: #2d2d2d;
    --text-color: #f0f0f0;
    --shadow-color: rgba(0,0,0,0.5);
    --ball-shadow: rgba(0,0,0,0.6);
    --btn-bg: #388E3C;
    --btn-hover-bg: #2E7D32;
    --btn-glow: rgba(56, 142, 60, 0.5);
}

body {
    font-family: sans-serif;
    background-color: var(--bg-color);
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='4' height='4' viewBox='0 0 4 4'%3E%3Cpath fill='%239C92AC' fill-opacity='0.1' d='M1 3h1v1H1V3zm2-2h1v1H3V1z'%3E%3C/path%3E%3C/svg%3E");
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    transition: background-color 0.3s ease;
}

.container {
    background-color: var(--container-bg);
    padding: 40px;
    border-radius: 16px;
    box-shadow: 0 10px 20px var(--shadow-color), 0 6px 6px var(--shadow-color);
    text-align: center;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
    position: relative;
}

h1 {
    color: var(--text-color);
    margin-bottom: 30px;
    font-size: 2.5rem;
}

.number-display {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 40px;
    min-height: 80px;
}

.lotto-ball {
    width: 70px;
    height: 70px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.8rem;
    font-weight: bold;
    color: #fff;
    box-shadow: 0 4px 8px var(--ball-shadow);
    transform: scale(0);
    animation: popIn 0.5s ease-in-out forwards;
}

.generate-btn {
    background-color: var(--btn-bg);
    color: white;
    padding: 15px 30px;
    border: none;
    border-radius: 8px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: background-color 0.3s, box-shadow 0.3s;
    box-shadow: 0 4px 6px var(--shadow-color);
}

.generate-btn:hover {
    background-color: var(--btn-hover-bg);
    box-shadow: 0 0 20px var(--btn-glow);
}

.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 5px;
    border-radius: 50%;
    transition: background-color 0.3s;
}

.theme-toggle:hover {
    background-color: rgba(128, 128, 128, 0.1);
}

@keyframes popIn {
    0% {
        transform: scale(0);
    }
    80% {
        transform: scale(1.1);
    }
    100% {
        transform: scale(1);
    }
}