dagon | The Esoteric Order of Dagon

You could use map method by passing replacement value for every key you need.

What I would recommend doing is setting the left property to 50% on the left-most and right-most ::before pseudo-classes, and then adjusting the width of the left-most and middle pseudo-classes to cover the offset.

I'd also recommend increasing the top of the downwards connectors by 2px just to avoid spiky 'overhangs'.

A bit sloppy, but here's my attempt:

This is a sample of one line of the OP's XML file
109555912.69

The OP wants to use the IMPORTXML function to report the ID and Name as well as the Job Cost from the XML data. Presently, the OP's formula is:
=importxml("link","//job-base-cost")

There are two options:
1 - One long column
=importxml("link","//@id | //@name | //job-base-cost")

Note //@id and //@name in the xpath query: // indicate nodes in the document (at any level, not just the root level) and @ indicate attributes. The pipe | operator indicates AND. So the plain english query is to display the id, name and job-base-cost.

2 - Three columns (table format)
={IMPORTXML("link","//@name"),IMPORTXML("link","//job-base-cost"),IMPORTXML("link","//@id")}

This creates a series that will display the fields in each of three columns.

Note: there is an arrayformula that uses a single importXML function described in How do I return multiple columns of data using ImportXML in Google Spreadsheets?. Readers may want to look at whether that option can be implemented.

My thanks to @Tanaike for his comment which spurred me to look at how xpath works.