#fep-app {
    max-width: 1000px;
    margin: 20px auto;
    font-family: Arial;
}

.fep-header {
    background: #eee;
    padding: 10px;
}

.fep-product {
    margin-top: 5px;
}

.fep-shapes {
    border: 1px solid #ccc;
    padding: 10px;
    margin: 10px 0;
}

.fep-shapes button {
    margin: 5px;
    padding: 10px;
    cursor: pointer;
}

.fep-room {
    display: flex;
    gap: 10px;
    margin-bottom: 10px;
}

#fep-canvas {
    border: 1px solid #ccc;
    background: #fafafa;
}

.fep-result {
    margin: 10px 0;
    font-weight: bold;
}

#fep-calc {
    background: #28a745;
    color: #fff;
    padding: 10px 15px;
    border: none;
    cursor: pointer;
}