Chart Prompts

Restyle my chart in the "Forge Temper" 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 bladesmith's tempering log. Black steel, hot color and one decisive white quench: the line changes color as the metal heats, exactly the way oxide colors run along a blade.

Colors (use these exact values):
- Background: #0E0E10 (black steel), with a soft radial lift to #17171A at the center.
- Temper colors by value band: bare steel #5A5E66 below the first band, then #E8C872 (straw), #B8783A (bronze), #9A5CC0 (purple), #4A7FE0 (temper blue) and #8C9096 (gray) for the top band.
- Quench line and its label: #FFFFFF. Title: #F4F1EA. Secondary text: #8A8780. Gridlines: #26262B.

Typography (Google Fonts):
- Bitter for the title (700, 29px, #F4F1EA, stating the finding) and the subtitle (400, 15px, #8A8780) and source (12px).
- Teko for every label: eyebrow 500 17px with 2.5px letter-spacing; axis labels 18px; color tags 600 18px with 0.8px letter-spacing; quench label 600 20px white with a 17px #8A8780 second line; "MINUTES" axis title 500 15px with 2px letter-spacing.

Layout:
- 56px margins. Eyebrow at y 58, title at y 98, subtitle at y 126. Two staggered rows of color tags at y 144 and y 176. Plot from x 96 to 900, y 214 to 492. Source at the bottom left.

Axes and grid:
- 1px #26262B gridlines at round values with Teko labels right-aligned 12px left of the plot, units in the label (e.g. 300°).
- Each band's lower edge is a 0.8px dashed line (2 on, 5 off) in its own color at 45% opacity.
- 6px ticks below the plot with Teko 18px labels.

Marks:
- Line chart: one 4px round-capped line stroked with a vertical userSpaceOnUse gradient that has hard stops at the band edges, so the line is straw, bronze, purple, blue or gray depending on its value. Add a 5px blur glow merged under the line (filter region covering the whole canvas). Under the line, an area filled with the same gradient masked to fade from 22% opacity at the top to 0 at the baseline. After the quench the line continues in bare steel #5A5E66 at 2.5px.
- Bar chart: bars colored by the band their value falls in (same hard-stop gradient, userSpaceOnUse, so a tall bar shows each band it passes), 2px radius tops, a 4px blur glow, and the white quench or threshold rule across all bars.
- Color tags: 24px tall, 3px radius, filled with the band color (dark text on straw, bronze and gray, white text on purple and blue), centered at the moment the line first enters that band, with a 1px dotted drop line in the band color to a 3.5px dot on the line. A band never reached gets a dashed outline tag in its color and a "NOT REACHED" note.
- Quench: a sharp 1.6px white vertical line through the whole plot at the quench time, a 5px ring on the line where it meets it, and a two-line label to its right.

Avoid: rainbow gradients unrelated to the value, soft pastel colors, gridlines brighter than the data, rounded frames and any second glowing element.

When you're done, render the chart and check that the color change happens exactly at the band edges, every tag sits over its entry point without overlapping its neighbor, the glow is not clipped, and the quench value in the title matches the data.