It is not exactly those lines. Remember the surround parameter from earlier? This is where you can just adjust the hanging-indent. Just make sure that the first-line-indent is also set to some relevant value.
Adapted from the default surround:
make-index(
...
surround: body => {
set par(
first-line-indent: 0pt,
spacing: 0.65em,
hanging-indent: 2em) // Try this if you use only level 1 and 2
body
},
...
)
Note: Also be aware of the box(width: lvl * 1em) that is inserted in front of every entry, which creates a manual first line indent. This may interfere with the way the hanging indent is displayed depending of the nested level. If you use nested level 3, a value over 2em would produce a visible result.
MWE with 3 nested levels
#import "@preview/in-dexter:0.7.2": *
#set page(paper: "a7")
#index("level1")
// Nested level3
#index("level2", lorem(8))
#index("level3", lorem(8), lorem(12))
// Debug - show the manual `first line indent`
#set box(stroke: red + 0.5pt)
#make-index(
title: "INDEX",
inline-page-numbers: true, // Custom parameter
entry-casing: x => x,
use-bang-grouping: true,
use-page-counter: true,
sort-order: upper,
surround: body => {
set par(
first-line-indent: 0em,
spacing: 0.65em,
hanging-indent: 2.5em,
)
body
},
)
