body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f3f3f3;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    background-color: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    margin-top: 0;
    margin-bottom: 20px;
    color: #333;
}

form {
    display: flex;
    flex-direction: column;
}

label {
    margin-bottom: 10px;
    color: #555;
    font-weight: bold;
}

.input-group {
    display: flex;
    align-items: center;
    margin-bottom: 15px;
}

.input-group select,
.input-group input[type="number"],
.input-group input[type="text"] {
    margin-left: 10px;
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 4px;
}

.input-group .btn-remove {
    margin-left: 10px;
    padding: 6px 12px;
    background-color: #007bff;
    color: white;
    border: none;
    cursor: pointer;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.input-group .btn-remove:hover {
    background-color: #0069d9;
}

#results {
    margin-top: 20px;
    text-align: center;
    font-weight: bold;
}

.btn-primary,
.btn-remove {
    text-align: center;
    border-radius: 4px;
}

.btn-primary {
    padding: 10px 20px;
    background-color: #007bff;
    color: white;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    background-color: #0069d9;
}

.btn-remove {
    padding: 6px 12px;
    background-color: #dc3545;
    color: white;
    border: none;
    cursor: pointer;
}

.btn-remove:hover {
    background-color: #c82333;
}

.result-item {
    border-bottom: 1px solid #ccc;
    padding-bottom: 10px;
    margin-bottom: 10px;
}

.result-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
    margin-bottom: 0;
}

.result-item p {
    margin: 0;
    text-align: left;
    color: #555;
}

.result-item strong {
    font-weight: bold;
}

.total-cost {
    font-size: 24px;
    font-weight: bold;
    margin-top: 15px;
    text-align: center;
    color: #555;
}

::placeholder {
    color: #bbb;
}

.shake {
    animation: shake 0.3s ease-in-out;
}

@keyframes shake {
    0% { transform: translateX(0); }
    25% { transform: translateX(-8px); }
    50% { transform: translateX(8px); }
    75% { transform: translateX(-8px); }
    100% { transform: translateX(0); }
}