:root {
    --background-color: #1a1a1a;
    --text-color: #ffffff;
    --accent-color: #ffde59;
    --container-background: #2c2c2c;
    --button-background: #3a3a3a;
    --button-hover-background: #4a4a4a;
    --shadow-color: rgba(0, 0, 0, 0.5);
    --bg-pattern: #333333;
}

[data-theme='light'] {
    --background-color: #f0f2f5;
    --text-color: #1a1a1a;
    --accent-color: #f57c00;
    --container-background: #ffffff;
    --button-background: #e4e6eb;
    --button-hover-background: #d8dadf;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --bg-pattern: #cccccc;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 60px 20px;
    box-sizing: border-box;
    transition: background-color 0.3s, color 0.3s;
    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='%23333333' fill-opacity='0.4' d='M1 3h1v1H1V3zm2-2h1v1H3V1z'%3E%3C/path%3E%3C/svg%3E");
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    background-color: var(--button-background);
    color: var(--text-color);
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.5rem;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 4px 10px var(--shadow-color);
    transition: transform 0.2s, background-color 0.3s;
}

.theme-toggle:hover {
    transform: scale(1.1);
    background-color: var(--button-hover-background);
}