:root {
    --bg-color: #fff;
    --text-color: #222;
    --button-bg: #eee;
    --button-text: #222;
}

[data-theme="dark"] {
    --bg-color: #121212;
    --text-color: #eee;
    --button-bg: #333;
    --button-text: #eee;
}

body {
    margin: 0;
    height: 100vh;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-family:
        -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu,
        Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
    transition:
        background-color 0.3s ease,
        color 0.3s ease;
}

h1 {
    margin-bottom: 1rem;
    font-size: 3rem;
    text-align: center;
}

button#toggleTheme {
    background-color: var(--button-bg);
    color: var(--button-text);
    border: none;
    padding: 0.6rem 1.2rem;
    border-radius: 4px;
    font-size: 1rem;
    cursor: pointer;
    transition:
        background-color 0.3s ease,
        color 0.3s ease;
    user-select: none;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

button#toggleTheme:focus {
    outline: 2px solid #007bff;
    outline-offset: 2px;
}

.japanese-text {
    font-family: "Sawarabi Mincho", serif;
    font-weight: normal;
    font-size: 1.5rem;
    margin-top: 0;
    color: var(--text-color);
    transition: color 0.3s ease;
}

/* Style for Material Symbols Rounded */
.material-symbols-rounded {
    font-variation-settings:
        "FILL" 1,
        "wght" 300,
        "GRAD" 0,
        "opsz" 48;
    font-family: "Material Symbols Rounded";
    vertical-align: middle;
    user-select: none;
    color: var(--text-color);
    transition: color 0.3s ease;
}

/* Style for Font Awesome icons */
.fa-solid {
    font-family: "Font Awesome 6 Free";
    font-weight: 900;
    vertical-align: middle;
    user-select: none;
    color: var(--text-color);
    transition: color 0.3s ease;
    font-size: 48px;
}

/* Container for icons to center-align */
#iconContainer {
    margin-top: 1.5rem;
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    align-items: center;
}