diff --git a/plots/ohlc-bar/implementations/python/highcharts.py b/plots/ohlc-bar/implementations/python/highcharts.py
index 6210e0a9c8..7949d2dce8 100644
--- a/plots/ohlc-bar/implementations/python/highcharts.py
+++ b/plots/ohlc-bar/implementations/python/highcharts.py
@@ -1,10 +1,11 @@
-""" pyplots.ai
+""" anyplot.ai
 ohlc-bar: OHLC Bar Chart
-Library: highcharts unknown | Python 3.13.11
-Quality: 91/100 | Created: 2026-01-09
+Library: highcharts unknown | Python 3.13.13
+Quality: 88/100 | Updated: 2026-05-23
 """
 
 import json
+import os
 import tempfile
 import time
 import urllib.request
@@ -12,18 +13,29 @@
 from pathlib import Path
 
 import numpy as np
+from PIL import Image
 from selenium import webdriver
 from selenium.webdriver.chrome.options import Options
 
 
-# Data - 50 trading days of simulated stock prices
+# Theme tokens
+THEME = os.getenv("ANYPLOT_THEME", "light")
+PAGE_BG = "#FAF8F1" if THEME == "light" else "#1A1A17"
+ELEVATED_BG = "#FFFDF6" if THEME == "light" else "#242420"
+INK = "#1A1A17" if THEME == "light" else "#F0EFE8"
+INK_SOFT = "#4A4A44" if THEME == "light" else "#B8B7B0"
+GRID = "rgba(26,26,23,0.10)" if THEME == "light" else "rgba(240,239,232,0.10)"
+
+# Semantic exception: finance — green=bullish/up, red=bearish/down (anyplot positions 1 and 3)
+UP_COLOR = "#009E73"
+DOWN_COLOR = "#B71D27"
+
+# Data — 50 trading days of simulated stock prices
 np.random.seed(42)
 
-# Start price and generate OHLC data
 start_price = 150.0
 n_days = 50
 
-# Generate realistic stock movements
 opens = [start_price]
 highs = []
 lows = []
@@ -34,9 +46,8 @@
     if i > 0:
         opens.append(open_price)
 
-    # Daily volatility
     daily_range = abs(np.random.randn() * 2) + 0.5
-    direction = np.random.choice([-1, 1], p=[0.48, 0.52])  # Slight bullish bias
+    direction = np.random.choice([-1, 1], p=[0.48, 0.52])
 
     close_price = open_price + direction * np.random.rand() * daily_range
     high_price = max(open_price, close_price) + abs(np.random.randn() * 0.8)
@@ -48,110 +59,133 @@
 
 opens = [round(o, 2) for o in opens]
 
-# Generate dates (trading days, skip weekends)
+# 5-day SMA for trend layer
+sma_period = 5
+sma_closes = []
+for i in range(sma_period - 1, n_days):
+    avg = sum(closes[i - sma_period + 1 : i + 1]) / sma_period
+    sma_closes.append(round(avg, 2))
+
+# Generate trading dates (skip weekends)
 start_date = datetime(2024, 6, 1)
 dates = []
 current_date = start_date
 while len(dates) < n_days:
-    if current_date.weekday() < 5:  # Monday to Friday
+    if current_date.weekday() < 5:
         dates.append(current_date)
     current_date += timedelta(days=1)
 
-# Format data for Highcharts: [timestamp, open, high, low, close]
+# Format as Highcharts timestamps: [timestamp_ms, open, high, low, close]
 ohlc_data = []
 for i in range(n_days):
-    timestamp = int(dates[i].timestamp() * 1000)  # JavaScript timestamp in ms
+    timestamp = int(dates[i].timestamp() * 1000)
     ohlc_data.append([timestamp, opens[i], highs[i], lows[i], closes[i]])
 
-# Chart options for Highcharts Stock OHLC chart
-# Using colorblind-safe palette: Python Blue for down bars, Python Yellow for up bars
+sma_data = []
+for i in range(sma_period - 1, n_days):
+    timestamp = int(dates[i].timestamp() * 1000)
+    sma_data.append([timestamp, sma_closes[i - (sma_period - 1)]])
+
+# Net-change subtitle for data storytelling
+net_change = closes[-1] - opens[0]
+pct_change = net_change / opens[0] * 100
+sign = "+" if net_change >= 0 else ""
+subtitle_text = f"Jun–Aug 2024  ·  Net change: {sign}${net_change:.2f} / {sign}{pct_change:.1f}%"
+
+title = "ohlc-bar · python · highcharts · anyplot.ai"
+
 chart_options = {
     "chart": {
         "type": "ohlc",
-        "width": 4800,
-        "height": 2700,
-        "backgroundColor": "#ffffff",
-        "marginBottom": 220,
-        "marginLeft": 250,
+        "width": 3200,
+        "height": 1800,
+        "backgroundColor": PAGE_BG,
+        "plotBorderWidth": 0,
+        "marginBottom": 160,
+        "marginLeft": 200,
         "marginRight": 80,
         "marginTop": 150,
-        "style": {"fontFamily": "Arial, sans-serif"},
-    },
-    "title": {
-        "text": "ohlc-bar · highcharts · pyplots.ai",
-        "style": {"fontSize": "72px", "fontWeight": "bold", "color": "#333333"},
-        "y": 60,
+        "style": {"fontFamily": "Arial, sans-serif", "color": INK},
     },
+    "title": {"text": title, "style": {"fontSize": "66px", "fontWeight": "600", "color": INK}, "y": 55},
+    "subtitle": {"text": subtitle_text, "style": {"fontSize": "36px", "color": INK_SOFT}, "y": 110},
     "xAxis": {
         "type": "datetime",
-        "title": {"text": "Date", "style": {"fontSize": "52px", "color": "#333333"}, "margin": 30},
-        "labels": {
-            "style": {"fontSize": "36px", "color": "#333333"},
-            "format": "{value:%b %d}",
-            "y": 45,
-            "step": 3,  # Show every 3rd label to prevent overlap
-        },
+        "title": {"text": "Date", "style": {"fontSize": "56px", "color": INK}, "margin": 25},
+        "labels": {"style": {"fontSize": "44px", "color": INK_SOFT}, "format": "{value:%b %d}", "y": 40, "step": 3},
         "gridLineWidth": 1,
-        "gridLineColor": "rgba(0, 0, 0, 0.15)",
-        "gridLineDashStyle": "Dash",
-        "lineWidth": 3,
-        "lineColor": "#333333",
-        "tickWidth": 3,
-        "tickColor": "#333333",
-        "tickLength": 15,
+        "gridLineColor": GRID,
+        "lineWidth": 2,
+        "lineColor": INK_SOFT,
+        "tickWidth": 2,
+        "tickColor": INK_SOFT,
+        "tickLength": 10,
     },
     "yAxis": {
-        "title": {"text": "Price (USD)", "style": {"fontSize": "52px", "color": "#333333"}, "margin": 30},
-        "labels": {"style": {"fontSize": "36px", "color": "#333333"}, "format": "${value:.0f}", "x": -15},
+        "title": {"text": "Price (USD)", "style": {"fontSize": "56px", "color": INK}, "margin": 25},
+        "labels": {"style": {"fontSize": "44px", "color": INK_SOFT}, "format": "${value:.0f}", "x": -15},
         "gridLineWidth": 1,
-        "gridLineColor": "rgba(0, 0, 0, 0.15)",
-        "gridLineDashStyle": "Dash",
-        "lineWidth": 3,
-        "lineColor": "#333333",
-        "opposite": False,  # Keep Y-axis on left side only
+        "gridLineColor": GRID,
+        "lineWidth": 2,
+        "lineColor": INK_SOFT,
+        "opposite": False,
+    },
+    "legend": {
+        "enabled": True,
+        "itemStyle": {"color": INK_SOFT, "fontSize": "36px", "fontWeight": "normal"},
+        "backgroundColor": "transparent",
+        "borderWidth": 0,
+        "align": "right",
+        "verticalAlign": "top",
+        "layout": "vertical",
+        "x": -80,
+        "y": 160,
     },
-    "legend": {"enabled": False},
     "tooltip": {
         "split": False,
-        "style": {"fontSize": "28px"},
+        "style": {"fontSize": "32px"},
         "headerFormat": "<b>{point.x:%b %d, %Y}</b><br/>",
         "pointFormat": "Open: ${point.open:.2f}<br/>"
         + "High: ${point.high:.2f}<br/>"
         + "Low: ${point.low:.2f}<br/>"
         + "Close: ${point.close:.2f}",
     },
-    "plotOptions": {
-        "ohlc": {
-            # Colorblind-safe: Python Yellow for up bars, Python Blue for down bars
-            "color": "#306998",  # Python Blue for down bars (close < open)
-            "upColor": "#FFD43B",  # Python Yellow for up bars (close > open)
-            "lineWidth": 5,  # Bar line width - visible at large size
-        }
-    },
+    "plotOptions": {"ohlc": {"color": DOWN_COLOR, "upColor": UP_COLOR, "lineWidth": 4}},
     "rangeSelector": {"enabled": False},
     "navigator": {"enabled": False},
     "scrollbar": {"enabled": False},
     "credits": {"enabled": False},
-    "series": [{"type": "ohlc", "name": "Stock Price", "data": ohlc_data}],
+    "series": [
+        {"type": "ohlc", "name": "Stock Price", "data": ohlc_data},
+        {
+            "type": "line",
+            "name": "5-day SMA",
+            "data": sma_data,
+            "color": INK_SOFT,
+            "lineWidth": 2,
+            "dashStyle": "Dash",
+            "enableMouseTracking": False,
+            "marker": {"enabled": False},
+        },
+    ],
 }
 
-# Download Highstock JS (includes OHLC support)
-highstock_url = "https://code.highcharts.com/stock/highstock.js"
-with urllib.request.urlopen(highstock_url, timeout=30) as response:
+# Download Highstock JS (OHLC type lives in Highstock)
+highstock_url = "https://cdn.jsdelivr.net/npm/highcharts/highstock.js"
+req = urllib.request.Request(highstock_url, headers={"User-Agent": "Mozilla/5.0"})
+with urllib.request.urlopen(req, timeout=30) as response:
     highstock_js = response.read().decode("utf-8")
 
-# Generate chart options JSON
 chart_options_json = json.dumps(chart_options)
 
-# Generate HTML with inline scripts
 html_content = f"""<!DOCTYPE html>
 <html>
 <head>
     <meta charset="utf-8">
     <script>{highstock_js}</script>
 </head>
-<body style="margin:0; background-color: #ffffff;">
-    <div id="container" style="width: 4800px; height: 2700px;"></div>
+<body style="margin:0; background:{PAGE_BG};">
+    <div id="container" style="width: 3200px; height: 1800px;"></div>
     <script>
         document.addEventListener('DOMContentLoaded', function() {{
             Highcharts.stockChart('container', {chart_options_json});
@@ -160,28 +194,37 @@
 </body>
 </html>"""
 
-# Write temp HTML file
-with tempfile.NamedTemporaryFile(mode="w", suffix=".html", delete=False, encoding="utf-8") as f:
+# Save HTML artifact
+with open(f"plot-{THEME}.html", "w", encoding="utf-8") as f:
     f.write(html_content)
-    temp_path = f.name
 
-# Also save the HTML for interactive viewing
-with open("plot.html", "w", encoding="utf-8") as f:
+# Write temp HTML and take screenshot
+with tempfile.NamedTemporaryFile(mode="w", suffix=".html", delete=False, encoding="utf-8") as f:
     f.write(html_content)
+    temp_path = f.name
 
-# Take screenshot with headless Chrome
 chrome_options = Options()
-chrome_options.add_argument("--headless")
+chrome_options.add_argument("--headless=new")
 chrome_options.add_argument("--no-sandbox")
 chrome_options.add_argument("--disable-dev-shm-usage")
 chrome_options.add_argument("--disable-gpu")
-chrome_options.add_argument("--window-size=4800,2700")
+chrome_options.add_argument("--hide-scrollbars")
+chrome_options.add_argument("--window-size=3200,1800")
 
 driver = webdriver.Chrome(options=chrome_options)
+driver.execute_cdp_cmd(
+    "Emulation.setDeviceMetricsOverride", {"width": 3200, "height": 1800, "deviceScaleFactor": 1, "mobile": False}
+)
 driver.get(f"file://{temp_path}")
 time.sleep(5)
-driver.save_screenshot("plot.png")
+driver.save_screenshot(f"plot-{THEME}.png")
 driver.quit()
 
-# Clean up temp file
 Path(temp_path).unlink()
+
+# Pin to exact canvas dimensions
+_img = Image.open(f"plot-{THEME}.png").convert("RGB")
+if _img.size != (3200, 1800):
+    _norm = Image.new("RGB", (3200, 1800), PAGE_BG)
+    _norm.paste(_img, ((3200 - _img.size[0]) // 2, (1800 - _img.size[1]) // 2))
+    _norm.save(f"plot-{THEME}.png")
diff --git a/plots/ohlc-bar/metadata/python/highcharts.yaml b/plots/ohlc-bar/metadata/python/highcharts.yaml
index 634b7f32ed..7508d3292e 100644
--- a/plots/ohlc-bar/metadata/python/highcharts.yaml
+++ b/plots/ohlc-bar/metadata/python/highcharts.yaml
@@ -1,161 +1,184 @@
 library: highcharts
+language: python
 specification_id: ohlc-bar
 created: '2026-01-09T08:18:41Z'
-updated: '2026-01-09T08:21:19Z'
-generated_by: claude-opus-4-5-20251101
-workflow_run: 20845567100
+updated: '2026-05-23T22:09:50Z'
+generated_by: claude-sonnet
+workflow_run: 26344376368
 issue: 3293
-python_version: 3.13.11
+language_version: 3.13.13
 library_version: unknown
-preview_url: https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/highcharts/plot.png
-preview_html: https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/highcharts/plot.html
-quality_score: 91
+preview_url_light: https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/python/highcharts/plot-light.png
+preview_url_dark: https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/python/highcharts/plot-dark.png
+preview_html_light: https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/python/highcharts/plot-light.html
+preview_html_dark: https://storage.googleapis.com/anyplot-images/plots/ohlc-bar/python/highcharts/plot-dark.html
+quality_score: 88
 review:
   strengths:
-  - Excellent use of colorblind-safe Python Blue/Yellow palette for up/down differentiation
-  - Proper Highstock OHLC chart type implementation with correct bar structure
-  - Realistic 50-day stock data with weekend skipping and proper OHLC relationships
-  - Clean title format following specification
-  - Well-configured tooltips with all OHLC values formatted nicely
-  - Appropriate grid styling with subtle dashed lines
+  - 'Finance semantic exception correctly applied: green (#009E73) for up-bars, red
+    (#B71D27) for down-bars with explicit rationale in code comment.'
+  - Informative subtitle with computed net-change statistics adds real data storytelling
+    value.
+  - 5-day SMA overlay provides trend context without cluttering the OHLC display.
+  - Both themes render cleanly with no dark-on-dark or light-on-light failures.
+  - Perfect spec compliance and data quality; all 50 OHLC bars and SMA visible.
+  - Canvas pinning via CDP + PIL fallback prevents dimension drift.
   weaknesses:
-  - Bar line width could be slightly thicker for optimal visibility at 4800x2700 resolution
-  - Could leverage more Highstock features like zoom controls (though disabled is
-    acceptable for static export)
-  image_description: 'The plot displays an OHLC (Open-High-Low-Close) bar chart showing
-    50 trading days of simulated stock price data from June 3rd to August 8th. Each
-    trading day is represented by a vertical bar with horizontal tick marks: the vertical
-    line shows the high-low range, while left and right ticks indicate opening and
-    closing prices respectively. The chart uses a colorblind-safe palette with Python
-    Blue (#306998) for down bars (close < open) and Python Yellow (#FFD43B) for up
-    bars (close > open). The Y-axis shows "Price (USD)" ranging from $141 to $158
-    with dollar formatting. The X-axis shows dates formatted as "Mon DD" with labels
-    appearing every few days to prevent overlap. Dashed grid lines are visible in
-    both directions. The title "ohlc-bar · highcharts · pyplots.ai" appears at the
-    top. The data shows an overall upward trend with the price starting around $150,
-    dipping to a low around $142 in early July, then rallying to highs around $157
-    by early August.'
+  - Both horizontal and vertical gridlines enabled; for an OHLC financial chart, y-axis-only
+    gridlines are conventional and reduce visual noise — remove gridLineWidth from
+    xAxis.
+  - Red/green up/down coloring is the sole visual discriminator for CVD users; bar
+    direction provides secondary signal but a shape/pattern difference would improve
+    accessibility.
+  - Subtitle at 36px is smaller than tick labels at 44px, creating a hierarchy anomaly
+    — consider 40px for subtitle.
+  - Legend marker for ohlc series renders as a filled circle rather than an OHLC bar
+    symbol, which can mislead readers.
+  image_description: |-
+    Light render (plot-light.png):
+      Background: Warm off-white (#FAF8F1) — correct theme surface, not pure white
+      Chrome: Title "ohlc-bar · python · highcharts · anyplot.ai" in dark ink (#1A1A17) — clearly readable. Subtitle "Jun–Aug 2024 · Net change: +$5.40 / +3.6%" in muted ink (#4A4A44). Y-axis label "Price (USD)" and X-axis label "Date" in dark ink. Tick labels ($141–$158 on Y, Jun 04–Aug 09 on X) in muted ink.
+      Data: Up-bars in #009E73 (anyplot position 1), down-bars in #B71D27 (anyplot position 3). Dashed SMA line in muted gray. Legend in upper right with filled circle markers.
+      Legibility verdict: PASS
+
+    Dark render (plot-dark.png):
+      Background: Warm near-black (#1A1A17) — correct theme surface, not pure black
+      Chrome: Title in near-white (#F0EFE8) — clearly readable against dark background. Subtitle and tick labels in muted light gray (#B8B7B0). Axis labels in near-white. No dark-on-dark failures detected.
+      Data: Colors identical to light render — #009E73 up-bars and #B71D27 down-bars. Dashed SMA line in lighter muted gray. Data identity confirmed.
+      Legibility verdict: PASS
   criteria_checklist:
     visual_quality:
-      score: 36
-      max: 40
+      score: 28
+      max: 30
       items:
       - id: VQ-01
         name: Text Legibility
-        score: 9
-        max: 10
+        score: 7
+        max: 8
         passed: true
-        comment: Title, axis labels, and tick labels are all clearly readable at full
-          size. Font sizes appropriate for 4800x2700 canvas.
+        comment: All font sizes explicitly set; readable in both themes. Subtitle
+          at 36px slightly small vs tick labels at 44px.
       - id: VQ-02
         name: No Overlap
-        score: 8
-        max: 8
+        score: 6
+        max: 6
         passed: true
-        comment: No overlapping text elements. Date labels spaced appropriately with
-          step=3.
+        comment: No overlapping elements; date labels spaced with step=3.
       - id: VQ-03
         name: Element Visibility
-        score: 7
-        max: 8
+        score: 6
+        max: 6
         passed: true
-        comment: OHLC bars clearly visible with lineWidth=5. Bars could be slightly
-          thicker for optimal visibility.
+        comment: OHLC bars at lineWidth=4 well-proportioned for 50 data points; SMA
+          clearly distinguishable.
       - id: VQ-04
         name: Color Accessibility
-        score: 5
-        max: 5
+        score: 1
+        max: 2
         passed: true
-        comment: Excellent colorblind-safe Python Blue/Yellow palette. Avoids red-green
-          conflicts.
+        comment: Finance semantic exception valid; bar direction provides secondary
+          signal; red-green as primary CVD concern.
       - id: VQ-05
-        name: Layout Balance
+        name: Layout & Canvas
         score: 4
-        max: 5
+        max: 4
         passed: true
-        comment: Good layout with appropriate margins. Plot area fills good portion
-          of canvas.
+        comment: Canvas 3200x1800 confirmed. Good plot area utilization, balanced
+          margins.
       - id: VQ-06
-        name: Axis Labels
+        name: Axis Labels & Title
         score: 2
         max: 2
         passed: true
-        comment: Date for X-axis and Price (USD) with unit for Y-axis.
+        comment: Price (USD) with units; Date; correct mandated title format.
       - id: VQ-07
-        name: Grid & Legend
-        score: 1
+        name: Palette Compliance
+        score: 2
         max: 2
         passed: true
-        comment: Grid subtle with dashed style and 0.15 alpha. Legend disabled appropriate
-          for single series.
+        comment: '#009E73 up-bars, #B71D27 down-bars via finance semantic exception.
+          Correct backgrounds both themes. Theme-adaptive chrome.'
+    design_excellence:
+      score: 12
+      max: 20
+      items:
+      - id: DE-01
+        name: Aesthetic Sophistication
+        score: 5
+        max: 8
+        passed: true
+        comment: Thoughtful financial color coding with semantic exception; subtitle
+          with computed stats adds polish. Above configured-default but not exceptional.
+      - id: DE-02
+        name: Visual Refinement
+        score: 3
+        max: 6
+        passed: true
+        comment: 'Clean layout; Highcharts default chrome is clean. Deduction: both
+          x+y gridlines present — OHLC charts conventionally use y-only horizontal
+          grid.'
+      - id: DE-03
+        name: Data Storytelling
+        score: 4
+        max: 6
+        passed: true
+        comment: Subtitle with net-change stats, SMA overlay for trend context, directional
+          color coding — good visual hierarchy.
     spec_compliance:
-      score: 25
-      max: 25
+      score: 15
+      max: 15
       items:
       - id: SC-01
         name: Plot Type
-        score: 8
-        max: 8
-        passed: true
-        comment: Correct OHLC bar chart type with proper vertical lines and horizontal
-          ticks.
-      - id: SC-02
-        name: Data Mapping
         score: 5
         max: 5
         passed: true
-        comment: Date on X-axis, price on Y-axis. OHLC values correctly mapped.
-      - id: SC-03
+        comment: Highstock native ohlc type with vertical bars and open/close tick
+          marks.
+      - id: SC-02
         name: Required Features
-        score: 5
-        max: 5
+        score: 4
+        max: 4
         passed: true
-        comment: 'All features present: vertical lines, horizontal ticks, color differentiation,
-          grid lines.'
-      - id: SC-04
-        name: Data Range
+        comment: High-low bars, open/close ticks, directional color, time axis, grid
+          lines all present.
+      - id: SC-03
+        name: Data Mapping
         score: 3
         max: 3
         passed: true
-        comment: All data visible within axis range.
-      - id: SC-05
-        name: Legend Accuracy
-        score: 2
-        max: 2
-        passed: true
-        comment: Legend appropriately disabled; tooltip provides detailed OHLC info.
-      - id: SC-06
-        name: Title Format
-        score: 2
-        max: 2
+        comment: Date on X, Price (USD) on Y, all 50 days visible.
+      - id: SC-04
+        name: Title & Legend
+        score: 3
+        max: 3
         passed: true
-        comment: 'Correct format: ohlc-bar · highcharts · pyplots.ai'
+        comment: Exact title format; Stock Price and 5-day SMA legend labels appropriate.
     data_quality:
-      score: 18
-      max: 20
+      score: 15
+      max: 15
       items:
       - id: DQ-01
         name: Feature Coverage
-        score: 7
-        max: 8
+        score: 6
+        max: 6
         passed: true
-        comment: Shows bullish and bearish bars, variety of bar sizes, overall trend.
-          Missing extreme outliers.
+        comment: 50 trading days with both bullish and bearish bars; dip then rally
+          shows full OHLC behavior range.
       - id: DQ-02
         name: Realistic Context
-        score: 6
-        max: 7
+        score: 5
+        max: 5
         passed: true
-        comment: Plausible stock price scenario with 50 trading days, skips weekends.
+        comment: Realistic stock price scenario Jun-Aug 2024; neutral financial domain.
       - id: DQ-03
         name: Appropriate Scale
-        score: 5
-        max: 5
+        score: 4
+        max: 4
         passed: true
-        comment: Price values $141-$157 sensible for stock data. Daily volatility
-          realistic.
+        comment: Starting price $150, +3.6% gain over 50 days; realistic daily ranges.
     code_quality:
-      score: 8
+      score: 10
       max: 10
       items:
       - id: CQ-01
@@ -163,52 +186,63 @@ review:
         score: 3
         max: 3
         passed: true
-        comment: 'Linear script: imports → data → config → HTML → screenshot.'
+        comment: 'Flat: imports → data → chart options → export.'
       - id: CQ-02
         name: Reproducibility
-        score: 3
-        max: 3
+        score: 2
+        max: 2
         passed: true
-        comment: np.random.seed(42) set for reproducible data.
+        comment: np.random.seed(42) set.
       - id: CQ-03
         name: Clean Imports
-        score: 1
+        score: 2
         max: 2
         passed: true
-        comment: All imports used, json could be replaced by direct string formatting.
+        comment: All imports used; no stale imports.
       - id: CQ-04
-        name: No Deprecated API
-        score: 1
-        max: 1
+        name: Code Elegance
+        score: 2
+        max: 2
         passed: true
-        comment: Uses current Highstock API.
+        comment: Clean, readable; appropriate complexity.
       - id: CQ-05
-        name: Output Correct
-        score: 0
+        name: Output & API
+        score: 1
         max: 1
-        passed: false
-        comment: Saves plot.png (correct) but also plot.html which wasn't required.
-    library_features:
-      score: 4
-      max: 5
+        passed: true
+        comment: Saves plot-{THEME}.png and plot-{THEME}.html; current Highstock API.
+    library_mastery:
+      score: 8
+      max: 10
       items:
-      - id: LF-01
+      - id: LM-01
+        name: Idiomatic Usage
+        score: 4
+        max: 5
+        passed: true
+        comment: Correct Highstock ohlc type; CDP viewport + PIL canvas pinning follow
+          library guide. Bypasses highcharts_core Python bindings, appropriate for
+          Highstock.
+      - id: LM-02
         name: Distinctive Features
         score: 4
         max: 5
         passed: true
-        comment: Uses Highstock's native OHLC type, datetime handling, upColor/color
-          for bar coloring.
+        comment: 'Highstock-specific: ohlc series type, upColor/color directional
+          coloring, rangeSelector/navigator/scrollbar disabled, stockChart constructor.'
   verdict: APPROVED
 impl_tags:
   dependencies:
   - selenium
+  - pillow
   techniques:
   - html-export
+  - hover-tooltips
   patterns:
   - data-generation
   - iteration-over-groups
   dataprep:
+  - rolling-window
   - time-series
   styling:
   - grid-styling