main.css

body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    display: flex;
    height: 100vh;
    background-color: #1e1e1e;
    color: #e0e0e0;
}
#editor {
    flex: 1;
    padding: 20px;
}
#textarea {
    width: 100%;
    height: calc(100vh - 60px);
    background-color: #2d2d2d;
    color: #e0e0e0;
    border: none;
    padding: 10px;
    font-family: monospace;
    resize: none;
}
#sidebar {
    width: 300px;
    height: 100vh;
    padding: 20px;
    background-color: #252526;
    overflow-y: auto;
    box-sizing: border-box;
}
button {
    width: 100%;
    padding: 10px;
    margin-bottom: 20px;
    background-color: #0e639c;
    color: white;
    border: none;
    cursor: pointer;
}
button:hover {
    background-color: #1177bb;
}
h3 {
    margin-top: 20px;
    margin-bottom: 10px;
    color: #4ec9b0;
}
.setting {
    margin-bottom: 15px;
}
.checkbox-container {
    display: flex;
    align-items: center;
    position: relative;
    padding-left: 35px;
    margin-bottom: 12px;
    cursor: pointer;
    font-size: 16px;
    user-select: none;
    min-height: 25px;
}
.checkbox-container input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}
.checkmark {
    position: absolute;
    top: 50%;
    left: 0;
    height: 25px;
    width: 25px;
    background-color: #eee;
    border-radius: 4px;
    transform: translateY(-50%);
}
.checkbox-container:hover input ~ .checkmark {
    background-color: #ccc;
}
.checkbox-container input:checked ~ .checkmark {
    background-color: #2196F3;
}
.checkmark:after {
    content: "";
    position: absolute;
    display: none;
}
.checkbox-container input:checked ~ .checkmark:after {
    display: block;
}
.checkbox-container .checkmark:after {
    left: 9px;
    top: 5px;
    width: 5px;
    height: 10px;
    border: solid white;
    border-width: 0 3px 3px 0;
    transform: rotate(45deg);
}

input[type="number"], select {
    width: 100%;
    padding: 5px;
    margin-top: 5px;
    background-color: #3c3c3c;
    color: #e0e0e0;
    border: 1px solid #555;
    border-radius: 4px;
}

select {
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    background-image: url('data:image/svg+xml;utf8,<svg fill="%23ffffff" height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"><path d="M7 10l5 5 5-5z"/><path d="M0 0h24v24H0z" fill="none"/></svg>');
    background-repeat: no-repeat;
    background-position-x: 100%;
    background-position-y: 5px;
}