.invoice-wrapper {
    max-width: 800px;
    padding: 20px;
    background: #fff;
    font-family: sans-serif;
}
.invoice-wrapper input, .invoice-wrapper textarea, .invoice-wrapper button, .invoice-wrapper select {
    display: block;
    width: 100%;
    margin-bottom: 10px;
}
#items-body td input {
    width: 100%;
}
table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 10px;
}
th, td {
    border: 1px solid #ccc;
    padding: 8px;
}

.spinner {
  border: 2px solid #f3f3f3;
  border-top: 2px solid #333;
  border-radius: 50%;
  width: 14px;
  height: 14px;
  animation: spin 1s linear infinite;
  display: inline-block;
  vertical-align: middle;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}