body {
    font-family: Arial, sans-serif;
    background: #f4f4f4;
    margin: 0;
    padding: 0;
}
.container {
    width: 80%;
    margin: auto;
    background: #fff;
    padding: 2em;
    margin-top: 2em;
    box-shadow: 0 0 10px #ccc;
}
.board {
    display: flex;
    gap: 1em;
}
.column {
    flex: 1;
    background: #eef;
    border-radius: 8px;
    padding: 1em;
}
.column h2 {
    text-align: center;
}
ul {
    list-style: none;
    padding: 0;
}
li {
    margin-bottom: 1em;
    background: #fff;
    padding: 0.5em;
    border-radius: 5px;
    box-shadow: 0 0 3px #ccc;
}
.btn {
    background-color: #3498db;
    color: #fff;
    padding: 0.5em 1em;
    text-decoration: none;
    border-radius: 5px;
    margin-bottom: 1em;
}
.small-btn {
    background: #2ecc71;
    color: #fff;
    padding: 0.2em 0.5em;
    font-size: 0.8em;
    border-radius: 3px;
    margin-top: 0.3em;
    display: inline-block;
}