:root {
    --bg-color: #f0f2f5;
    --container-bg-color: #ffffff;
    --text-color: #333;
    --button-bg-color: #007BFF;
    --button-hover-bg-color: #0056b3;
    --button-shadow-color: rgba(0, 123, 255, 0.4);
    --button-hover-shadow-color: rgba(0, 123, 255, 0.6);
}

[data-theme="dark"] {
    --bg-color: #282c36;
    --container-bg-color: #3b4252;
    --text-color: #eceff4;
    --button-bg-color: #88c0d0;
    --button-hover-bg-color: #81a1c1;
    --button-shadow-color: rgba(136, 192, 208, 0.4);
    --button-hover-shadow-color: rgba(136, 192, 208, 0.6);
}

body {
    font-family: sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: var(--bg-color);
    margin: 0;
    background-image: url("data:image/svg+xml,%3Csvg width='42' height='44' viewBox='0 0 42 44' xmlns='http://www.w3.org/2000/svg'%3E%3Cg id='Page-1' fill='none' fill-rule='evenodd'%3E%3Cg id='brick-wall' fill='%23cccccc' fill-opacity='0.4'%3E%3Cpath d='M0 0h42v44H0V0zm1 1h40v20H1V1zM0 23h20v20H0V23zm22 0h20v20H22V23z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    transition: background-color 0.3s ease;
}

.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
    background-color: var(--button-bg-color);
    color: white;
    border: none;
    padding: 10px 15px;
    font-size: 1rem;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.theme-toggle:hover {
    background-color: var(--button-hover-bg-color);
    transform: translateY(-2px);
}

.container {
    text-align: center;
    background-color: var(--container-bg-color);
    padding: 50px;
    border-radius: 20px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    transition: background-color 0.3s ease;
}

h1 {
    color: var(--text-color);
    font-size: 2.5rem;
    margin-bottom: 40px;
    font-weight: bold;
    transition: color 0.3s ease;
}

.lotto-numbers {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 40px;
}

.lotto-number {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    color: white;
    font-size: 1.8rem;
    font-weight: bold;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

#generate-btn {
    background-color: var(--button-bg-color);
    color: white;
    border: none;
    padding: 18px 35px;
    font-size: 1.2rem;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px var(--button-shadow-color);
}

#generate-btn:hover {
    background-color: var(--button-hover-bg-color);
    box-shadow: 0 8px 25px var(--button-hover-shadow-color);
    transform: translateY(-3px);
}