* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: "Segoe UI", Arial, sans-serif;
}

:root {
    --bg-color: #ffffff;
    --text-color: #000000;
    --nav-bg: #4CAF50;
    --nav-text: #ffffff;
    --sidebar-bg: #f1f1f1;
    --sidebar-hover: #cccccc;
    --sidebar-active: #4CAF50;
    --code-bg: #f8f8f8;
    --border-color: #e3e3e3;
    --button-bg: #4CAF50;
    --button-hover: #45a049;
}

[data-theme="dark"] {
    --bg-color: #1e1e1e;
    --text-color: #f1f1f1;
    --nav-bg: #2d2d2d;
    --sidebar-bg: #2d2d2d;
    --sidebar-hover: #444;
    --sidebar-active: #4CAF50;
    --code-bg: #2d2d2d;
    --border-color: #444;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    height: 100vh;
}

.topnav {
    background-color: var(--nav-bg);
    color: var(--nav-text);
    padding: 10px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: fixed;
    width: 100%;
    z-index: 10;
    height: 60px;
}

.topnav h1 {
    font-size: 20px;
}

.nav-controls {
    display: flex;
    gap: 15px;
}

.nav-controls input {
    padding: 5px;
    border-radius: 4px;
    border: none;
}

.theme-btn {
    background: transparent;
    color: white;
    border: 1px solid white;
    padding: 5px 10px;
    cursor: pointer;
    border-radius: 4px;
}

.sidebar {
    height: calc(100vh - 60px);
    width: 250px;
    position: fixed;
    top: 60px;
    left: 0;
    background-color: var(--sidebar-bg);
    overflow-x: hidden;
    padding-top: 20px;
    border-right: 1px solid var(--border-color);
}

.sidebar a {
    padding: 10px 15px;
    text-decoration: none;
    font-size: 16px;
    color: var(--text-color);
    display: block;
    cursor: pointer;
}

.sidebar a:hover {
    background-color: var(--sidebar-hover);
}

.sidebar a.active {
    background-color: var(--sidebar-active);
    color: white;
}

.main {
    margin-left: 250px;
    margin-top: 60px;
    padding: 20px;
    flex: 1;
    overflow-y: auto;
    height: calc(100vh - 60px);
}

.module-content {
    display: none;
    max-width: 900px;
    margin: 0 auto;
}

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

h2 {
    margin-bottom: 15px;
    color: var(--nav-bg);
}

p, ul, ol {
    margin-bottom: 15px;
    line-height: 1.5;
}

ul, ol {
    margin-left: 20px;
}

code {
    background-color: var(--code-bg);
    padding: 2px 5px;
    border-radius: 3px;
    color: #d63384;
    font-family: Consolas, monospace;
}

.editor-container {
    margin: 20px 0;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    overflow: hidden;
}

.editor-header {
    background-color: var(--sidebar-bg);
    padding: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
}

.run-btn {
    background-color: var(--button-bg);
    color: white;
    border: none;
    padding: 8px 15px;
    cursor: pointer;
    border-radius: 4px;
    font-weight: bold;
}

.run-btn:hover {
    background-color: var(--button-hover);
}

.editor-panes {
    display: flex;
    height: 400px;
}

.code-pane, .preview-pane {
    flex: 1;
    border: none;
    padding: 10px;
}

.code-pane {
    background-color: var(--code-bg);
    color: var(--text-color);
    border-right: 1px solid var(--border-color);
    font-family: Consolas, monospace;
    resize: none;
    white-space: pre;
    overflow-wrap: normal;
    overflow-x: auto;
}

.preview-pane {
    background-color: white;
}

.quiz-section {
    background-color: var(--sidebar-bg);
    padding: 20px;
    border-radius: 5px;
    margin-top: 30px;
}

.quiz-question {
    margin-bottom: 15px;
}

.quiz-options {
    margin-bottom: 10px;
}

.quiz-options label {
    display: block;
    margin-bottom: 5px;
    cursor: pointer;
}

.quiz-feedback {
    font-weight: bold;
    margin-top: 10px;
}

.footer-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
    padding-bottom: 40px;
}

.nav-btn {
    background-color: var(--button-bg);
    color: white;
    border: none;
    padding: 10px 20px;
    cursor: pointer;
    border-radius: 4px;
    text-decoration: none;
}

.nav-btn:hover {
    background-color: var(--button-hover);
}
.nav-btn[disabled] {
    background-color: #cccccc;
    cursor: not-allowed;
}

/* Mobile Responsiveness */
.menu-btn {
    display: none;
    background: transparent;
    color: white;
    border: 1px solid white;
    padding: 5px 10px;
    cursor: pointer;
    border-radius: 4px;
    margin-right: 10px;
}

@media screen and (max-width: 768px) {
    .menu-btn {
        display: inline-block;
    }
    .topnav h1 {
        font-size: 16px;
    }
    .sidebar {
        left: -250px;
        transition: 0.3s;
        z-index: 20;
    }
    .sidebar.show {
        left: 0;
    }
    .main {
        margin-left: 0;
    }
    .editor-panes {
        flex-direction: column;
        height: 600px;
    }
    .code-pane {
        border-right: none;
        border-bottom: 1px solid var(--border-color);
    }
}