:root {
    --bg-color: #ffffff;
    --text-color: #000000;
    --button-color: #007bff;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #1a1a1a;
        --text-color: #ffffff;
        --button-color: #0056b3;
    }
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    text-align: center;
}

input[type="file"] {
    margin: 20px 0;
    display: block;
    width: 100%;
    color: var(--text-color);
}

button {
    padding: 10px 20px;
    background-color: var(--button-color);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

button:disabled {
    background-color: #ccc;
}

.theme-switch {
    position: absolute;
    top: 20px;
    right: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

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

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--button-color);
}

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