Fix Invoice/Estimate template issues and Add Payment Receipt, Custom Payment Modes and Item units

resources/assets/sass/components/mail-test-modal.scss

@@ -0,0 +1,44 @@
+.mail-test-modal {
+
+    .card-footer {
+        display: flex;
+        justify-content: flex-end;
+        padding: 20px 20px;
+    }
+
+    .input-label {
+        text-align: end;
+        padding-right: 0;
+        position: relative;
+    }
+
+    .required {
+        position: absolute;
+        margin-left: 4px;
+        color: $ls-color-red;
+    }
+
+    .compound-tax-toggle {
+        display: flex;
+        align-items: center;
+        margin-top: 9px;
+    }
+
+}
+
+@media(max-width: $x-small-breakpoint ) {
+
+    .base-modal {
+
+        .mail-test-modal {
+            width: 100vw;
+
+            .input-label {
+                text-align: left;
+            }
+
+        }
+
+    }
+
+}