:root {
    --background-color: #f0f2f5;
    --container-background: white;
    --text-color: #333;
    --button-background: #4CAF50;
    --button-text: white;
    --lotto-number-background: #f8f8f8;
    --lotto-number-border: #ddd;
}

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

body.dark-mode {
    --background-color: #121212;
    --container-background: #1e1e1e;
    --text-color: #e0e0e0;
    --button-background: #0056b3;
    --lotto-number-background: #2a2a2a;
    --lotto-number-border: #444;
}

.container {
    text-align: center;
    background-color: var(--container-background);
    padding: 40px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    position: relative;
}

h1 {
    color: var(--text-color);
    margin-bottom: 20px;
}

#generate-btn {
    background-color: var(--button-background);
    color: var(--button-text);
    padding: 15px 32px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border: none;
    border-radius: 5px;
    transition: background-color 0.3s;
}

#generate-btn:hover {
    opacity: 0.9;
}

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

.lotto-number {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: var(--lotto-number-background);
    border: 1px solid var(--lotto-number-border);
    margin: 0 5px;
    font-size: 20px;
    font-weight: bold;
    color: var(--text-color);
    opacity: 0;
    transform: scale(0.5);
    animation: number-appear 0.5s forwards;
}

@keyframes number-appear {
    to {
        opacity: 1;
        transform: scale(1);
    }
}


.theme-switch-wrapper {
    position: absolute;
    top: 20px;
    right: 20px;
    display: flex;
    align-items: center;
}

.theme-switch {
    display: inline-block;
    height: 34px;
    position: relative;
    width: 60px;
}

.theme-switch input {
    display:none;
}

.slider {
    background-color: #ccc;
    bottom: 0;
    cursor: pointer;
    left: 0;
    position: absolute;
    right: 0;
    top: 0;
    transition: .4s;
}

.slider:before {
    background-color: #fff;
    bottom: 4px;
    content: "";
    height: 26px;
    left: 4px;
    position: absolute;
    transition: .4s;
    width: 26px;
}

input:checked + .slider {
    background-color: #2196F3;
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.slider.round {
    border-radius: 34px;
}

.slider.round:before {
    border-radius: 50%;
}