Chart Prompts

Restyle my chart in the "Engraved Certificate" 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 nineteenth-century share certificate engraved in intaglio. Bright white stock, one dark green-black ink, a guilloche border, a ribbon banner and fine line engraving. Formal, precise and trustworthy.

Colors (use these exact values):
- Stock: #FFFFFF for the whole canvas.
- Ink: #1B2A22 (green-black) for everything: border, text, lines and hatching. Shades come only from line density, never from gray fills or opacity.
- Serial red: #B0282E, used only for the serial number and one thin ring marking the key data point.

Typography (Google Fonts):
- Old Standard TT throughout. Ribbon title 700 23px uppercase with 3.4px letter-spacing, centered. Finding line italic 21px centered under the ribbon (state the finding, e.g. peak value and the change since). Subtitle 12px uppercase with 2.2px letter-spacing (measure, unit, period). Axis labels 15px. Callouts 700 16px. Serial 700 14px with 1.5px letter-spacing in red ("No. A 0418"). Corner and footer small caps 10 to 12px with 1.6 to 2px letter-spacing. Source italic 14px.

Layout:
- Guilloche border: along a rounded rectangle 34px inside the canvas (corner radius 14), draw 7 closed sine paths offset along the normal by 7.5 * sin(150t + phase) + 1.6 * sin(450t - 2 * phase), phases evenly spaced, plus 4 finer paths at amplitude 3.2 and 300 waves (0.35px). Stroke 0.5px ink, no fill. It must close seamlessly (whole-number wave counts over the perimeter).
- Frames: a 1.6px outer rule 23px in (radius 22), and inside the guilloche a 1.2px rule 45px in (radius 6) plus a 0.5px rule 50px in (radius 3).
- Ribbon banner centered at the top (about 504 x 42px at y 72): white fill, 1.4px ink outline, a 0.5px inner rule inset 5px, title centered inside. Behind each end a swallowtail tail (54px long, 12px lower, 18px notch) filled with 45° hatching (3px spacing, 0.9px lines at 55%) and a solid ink fold triangle where the band meets the tail.
- "EST. 1820"-style small caps at the left and the red serial at the right, level with the ribbon's middle. Finding line at y 160, subtitle at y 186, chart from y 232 to 470, footer at y 532 with the source left and a signature rule plus "REGISTRAR OF ..." small caps on the right.

Axes and grid:
- Dotted 0.5px ink gridlines (1 on, 3 off) at round values; y labels with the currency or unit symbol, right-aligned 14px left of the plot.
- A 1.6px baseline with a 0.5px rule 3px under it (a double rule). Ticks 0.9px, 7px at labeled years and 4px between.

Marks:
- Line chart: a smooth monotone curve, 2.2px ink, with a 6px white casing under it so it cuts cleanly through the hatching. Every point is an open circle (r 3.2, white fill, 1.2px ink). The area under the curve is engraved: horizontal lines every 3.2px (0.7px) crossed by diagonal lines every 5px at -38° (0.45px), clipped to the area. Mark the key point with a 6.5px red ring and a hairline leader to a bold callout.
- Bar chart: bars as open rectangles with a 1.2px ink outline filled with the same engraved hatching (horizontal plus diagonal), about 55% of the band; the key bar gets denser hatching (lines every 2px) and a thin red ring on its value; value labels 700 16px above the bars; the double-rule baseline.

Avoid: gray fills, gradients, color beyond the single red accent, sans serif type, drop shadows, and any fill that is not built from lines.

When you're done, render the chart and check that the guilloche closes without a seam, the ribbon text sits fully inside the band, the hatching reads as engraving at thumbnail size, only the serial and one ring are red, and the finding line is arithmetically true.