:root {
    --bg: #ffffff;
    --text: #333;
    --main-bg: #ffffff;
    --sidebar-bg: #f9f9f9;
    --link: #333;
    --link-hover: #000;
    --input-bg: #f5f5f5;
    --input-border: #ccc;
    --input-hover: #e0e0e0;
    --input-active: #d6d6d6;
}

[data-theme="dark"] {
    --bg: #1e1e1e;
    --text: #eaeaea;
    --main-bg: #2c2c2c;
    --sidebar-bg: #333;
    --link: #eaeaea;
    --link-hover: #ffffff;
    --input-bg: #444;
    --input-border: #666;
    --input-hover: #555;
    --input-active: #666;
}

* {
    box-sizing: border-box;
}

*::-webkit-scrollbar {
    display: none;
}

body {
    margin: 0;
    padding: 8px;
    height: 100vh;
    display: flex;
    overflow: hidden;
    font-family: "Zen Maru Gothic", serif;
    background-color: var(--bg);
    color: var(--text);
    transition: background-color 0.3s, color 0.3s;
}

/* Sidebar */
#sidebar {
    width: 200px;
    background-color: var(--sidebar-bg);
    color: var(--text);
    padding: 1rem;
    border-radius: 12px;
    box-shadow: inset 0 0 5px rgba(0, 0, 0, 0.05);
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-right: 8px;
    transition: background-color 0.3s, color 0.3s;
}

.menu-list {
    list-style: none;
    padding: 0;
    margin-top: 40px;
    width: 100%;
}

.menu-list li {
    margin-bottom: 20px;
    text-align: center;
}

.menu-list a {
    color: var(--link);
    text-decoration: none;
    font-size: 16px;
    font-weight: bold;
    display: block;
    margin: 4px 0;
    transition: color 0.3s;
}

.menu-list a:hover {
    color: var(--link-hover);
}

/* Main Content */
#main {
    flex: 1;
    background-color: var(--main-bg);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 0 8px rgba(0, 0, 0, 0.05);
    overflow-y: auto;
    text-align: center;
    transition: background-color 0.3s;
}

/* Sections */
.content-section {
    display: none;
}

.content-section.active {
    display: block;
}

/* Form Elements */
input,
button,
a {
    background-color: var(--input-bg);
    border: 1px solid var(--input-border);
    border-radius: 6px;
    padding: 6px 10px;
    margin: 4px 0;
    cursor: pointer;
    color: var(--text);
    font-size: 14px;
    transition: background-color 0.2s ease, transform 0.1s, color 0.3s;
    text-decoration: none;
}

input:hover,
button:hover,
a:hover {
    background-color: var(--input-hover);
}

input:active,
button:active,
a:active {
    background-color: var(--input-active);
    transform: scale(0.98);
}

/* Responsive */
@media (max-width: 768px) {
    body {
        flex-direction: column;
    }

    #sidebar {
        width: 100%;
        margin-right: 0;
        margin-bottom: 8px;
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: center;
    }

    .menu-list {
        margin-top: 0;
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: 12px;
    }

    .menu-list li {
        margin: 0;
    }

    #main {
        padding: 1rem;
    }
}