index.css

body {
    margin: 0;
    padding: 10px;
    font-family: Arial, Helvetica, sans-serif;
    min-width: 400px;
}
input {
    width: 100%;
    padding-left: 10px;
    padding-right: 10px;
    box-sizing: border-box;
    height: 30px;
    margin-bottom: 4px;
    border: 1px solid #5f9341;
}

#input-btn, #tab-btn {
    color: white;
    background-color: #5f9341;
    padding: 10px 20px;
    border: 1px solid #5f9341;
    cursor: pointer;
    font-weight: bold;
}

#delete-btn {
    background-color: white;
    color: #5f9341;
    padding: 10px 20px;
    border: 1px solid #5f9341;
    cursor: pointer;
    font-weight: bold;
}

ul {
    padding: 10px;
    margin-left: 15px;
}

li {
    color: #5f9341;
    list-style: none;
    margin-bottom: 7px;
}

li a {
    color: #5f9341;
}