Chart Prompts

Restyle my chart in the "Seasonal Spread" 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 grain analyst's seasonal chart on a dark slate screen. Quiet history in the background (a soft steel band and a dashed average), last year in a thin teal line, and this year in thick warm wheat so the story is the gap between them.

Colors (use these exact values):
- Canvas: #141C2B (dark slate blue).
- Historical min-max band: #4A6585 at 45% opacity.
- Historical average: #C9CFD8, 1.6px, dashed 6 on 4 off.
- Prior period: #2CB3A4 (teal), 1.6px.
- Current period: #E8C872 (wheat), 3.5px, and the eyebrow text.
- Text: #EEF1F6 primary, #8D98AB secondary. Gridlines: #243049; zero line and baseline #3A4966.

Typography (Google Fonts): Commissioner for all text.
- Eyebrow 12px 600 uppercase, 2.4px letter-spacing, wheat. Title 32px 600, -0.4px letter-spacing, #EEF1F6, stating the finding. Subtitle 16px 400 #8D98AB with measure, unit and period.
- Legend 13px (the current period's entry 600 in #EEF1F6), axis labels 12.5px, month initials 13px 500, the latest-value callout 18px 700 wheat with a 12.5px note under it, footer 12.5px.

Layout:
- 56px side margins; eyebrow at y 58, title y 100, subtitle y 130.
- An inline legend key directly under the subtitle at y 164: a 22 x 12px band swatch, then 22px line samples for average, prior and current, each followed by its label, left to right in that order.
- Plot from x 88 to x 872, y 206 to 508. Leave room to the right of the current line's end for its callout.
- Footer rule at y 556, a one-line note explaining the band on the left and the source on the right at y 580.

Axes and grid:
- Horizontal 1px #243049 gridlines every 5 units with signed labels on the left; the zero line slightly stronger (#3A4966, 1.2px). Unit label ("¢/bu") above the top label.
- The x axis is the calendar: single month initials (J F M A M J J A S O N D) centered in each month, with 6px ticks at month boundaries on a #3A4966 baseline.

Marks:
- Line chart: draw the band first (smooth monotone upper and lower edges), then the average, then the prior period, then the current period over an 8px canvas-colored halo so it cuts through the others. End the current line with a 5px wheat dot with a 2px canvas ring and a callout giving its value and how far it sits outside the band.
- Bar chart: show each period as a slim wheat bar (about 45% of the band) with the historical min-max drawn behind it as a wider steel-blue range bar at 45% opacity, the average as a short dashed #C9CFD8 tick across each range, and the prior period as a 2px teal tick.

Avoid: rounded cards, glows, gradients, more than one bright color, and a boxed legend.

When you're done, render the chart and check that the current line clearly reads above everything else, the teal and dashed gray lines are distinguishable where they overlap, and the callout's gap figure equals the latest value minus the band's top at that date.