Chart Prompts

Restyle my chart in the "Significance Bars" style described below. Keep my data, chart type, title meaning and units; change only the presentation. Use the charting library this project already uses (plain SVG if there is none). If the library can't express a detail, draw it in a custom layer instead of dropping it. Measurements assume a 960 x 600 chart; scale them proportionally.

Mood: a clean lab-results figure from an experimental biology paper. Honest and statistical: every observation is visible, uncertainty is explicit and pairwise tests are marked with brackets.

Colors (use these exact values):
- Page: #F3F4F6 (very light gray) behind everything; plot area #FFFFFF with a 1px #D3D7DD border.
- Treatment fills, colorblind safe, in this order: #0072B2 (blue), #E69F00 (orange), #009E73 (bluish green).
- Ink for bar outlines, whiskers, brackets, data point outlines, ticks and titles: #1A1A1A.
- Secondary text: #5B616B. Gridlines: #E7E9ED.

Typography (Google Fonts):
- Source Sans 3 throughout (quote the family name in CSS, it ends in a digit): title 700 27px stating the finding; subtitle 400 16px #5B616B with measure, unit, "mean ± s.e.m." and n; legend 600 15px; tick labels 15px; y axis title 600 15px rotated; group labels 700 17px; group means 14px #5B616B; footnote 14px; source 13px.
- Significance marks: asterisks 700 20px #1A1A1A; "n.s." italic 400 14px #5B616B.

Layout:
- 48px left margin. Title, subtitle, then a legend row at about y 110: 14px square swatches with 0.8px #1A1A1A outline, plus an open-circle key "Individual seedling" (or the unit of observation).
- White plot area from about x 104 to 912 and y 140 to 478, with y tick labels outside it on the gray page.
- Category groups centered at about 27% and 73% of the plot width; group label and a muted "Means a, b, c unit" line underneath.
- Footnote naming the test and the star thresholds ("** p < 0.01, *** p < 0.001, n.s. not significant") and a source line at the bottom.

Axes and grid:
- y axis starts at zero, with 5px outward ticks and horizontal 1px #E7E9ED gridlines inside the white area. Leave about 25% headroom above the tallest point for brackets.
- No x axis ticks; groups are labeled beneath.

Marks:
- Bar chart: 76px wide bars, 14px apart within a group, filled in treatment color with a 1px #1A1A1A outline and square corners, height = group mean. Over each bar, every observation as an open circle (r 3.6, 1.1px #1A1A1A stroke, white fill at 35% opacity) jittered horizontally within about ±17px. A 1.8px #1A1A1A whisker spanning mean ± s.e.m. with 18px caps at both ends.
- Brackets: 1.2px #1A1A1A, a horizontal bar 16px above the highest point in the group with short vertical drops toward each compared bar (5 to 7px); adjacent pairs share the lowest tier with 4px gaps at the shared bar, wider comparisons stack 36px higher. Label centered above each bracket.
- Line chart: 2px lines in the treatment colors joining means across an ordered x variable, filled circle markers r 4.5 with 1px #1A1A1A outline, the same whiskers with caps at each mean, raw observations as jittered open circles around each x position, and brackets drawn vertically at the right end between series that differ.

Avoid: gradients, shadows, rounded bars, 3D, dynamite plots without the raw points, significance marks without brackets, and color as the only cue when a label can do the job.

When you're done, render the chart and check that whiskers and caps are centered on each bar, jittered points stay inside their bar's width, no bracket touches a data point or another bracket, the star labels match the footnote's thresholds, and the title is true for the plotted means.