:root {
    --bg-color: #f0f0f0;
    --container-bg: white;
    --text-color: #333;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --number-bg: #eee;
}

[data-theme="dark"] {
    --bg-color: #1a1a2e;
    --container-bg: #16213e;
    --text-color: #eee;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --number-bg: #0f3460;
}

body {
    font-family: sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: var(--bg-color);
    transition: background-color 0.3s ease;
    margin: 0;
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    border: none;
    background-color: var(--container-bg);
    box-shadow: 0 2px 10px var(--shadow-color);
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    transition: all 0.3s ease;
    z-index: 1000;
}

.theme-toggle:hover {
    transform: scale(1.1);
}

.icon-sun,
.icon-moon {
    position: absolute;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.icon-moon {
    opacity: 0;
    transform: rotate(-90deg);
}

[data-theme="dark"] .icon-sun {
    opacity: 0;
    transform: rotate(90deg);
}

[data-theme="dark"] .icon-moon {
    opacity: 1;
    transform: rotate(0deg);
}

.container {
    text-align: center;
    background-color: var(--container-bg);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 0 10px var(--shadow-color);
    transition: all 0.3s ease;
}

h1 {
    margin-bottom: 1rem;
    color: var(--text-color);
    transition: color 0.3s ease;
}

.numbers-container {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.number {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: var(--number-bg);
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    transition: transform 0.3s ease;
}

.number:hover {
    transform: scale(1.1);
}

#generate-btn {
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
}

#generate-btn:hover {
    background-color: #45a049;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}