Transcription: Steps in Prokaryotes and Eukaryotes

"""
Visual Study Guide: Transcription (Prokaryotes & Eukaryotes) + Post-Transcriptional Modifications
Generated using ReportLab
"""

from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.units import mm, cm
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    HRFlowable, KeepTogether, PageBreak
)
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_JUSTIFY
from reportlab.platypus.flowables import Flowable
from reportlab.graphics.shapes import Drawing, Rect, String, Line, Polygon, Circle, Arrow
from reportlab.graphics import renderPDF
from reportlab.graphics.shapes import Group
import math

# ── Colour Palette ──────────────────────────────────────────────────────────
NAVY       = colors.HexColor("#1A3A5C")
TEAL       = colors.HexColor("#0E7490")
CYAN_LIGHT = colors.HexColor("#CFFAFE")
BLUE_MID   = colors.HexColor("#3B82F6")
BLUE_LIGHT = colors.HexColor("#DBEAFE")
GREEN_DARK = colors.HexColor("#065F46")
GREEN_MID  = colors.HexColor("#10B981")
GREEN_LIGHT= colors.HexColor("#D1FAE5")
PURPLE_MID = colors.HexColor("#7C3AED")
PURPLE_LIGHT=colors.HexColor("#EDE9FE")
ORANGE_MID = colors.HexColor("#D97706")
ORANGE_LIGHT=colors.HexColor("#FEF3C7")
RED_MID    = colors.HexColor("#DC2626")
RED_LIGHT  = colors.HexColor("#FEE2E2")
GREY_LIGHT = colors.HexColor("#F1F5F9")
GREY_MID   = colors.HexColor("#94A3B8")
GREY_DARK  = colors.HexColor("#334155")
WHITE      = colors.white
BLACK      = colors.black
PINK_LIGHT = colors.HexColor("#FCE7F3")
PINK_MID   = colors.HexColor("#DB2777")

PAGE_W, PAGE_H = A4

# ── Styles ───────────────────────────────────────────────────────────────────
styles = getSampleStyleSheet()

def make_style(name, parent="Normal", **kwargs):
    return ParagraphStyle(name, parent=styles[parent], **kwargs)

S_TITLE     = make_style("Title2",   fontName="Helvetica-Bold",  fontSize=22, textColor=WHITE,       alignment=TA_CENTER, spaceAfter=4)
S_SUBTITLE  = make_style("Sub2",     fontName="Helvetica",       fontSize=11, textColor=CYAN_LIGHT,  alignment=TA_CENTER, spaceAfter=2)
S_H1        = make_style("H1",       fontName="Helvetica-Bold",  fontSize=14, textColor=WHITE,       spaceBefore=6, spaceAfter=4)
S_H2        = make_style("H2",       fontName="Helvetica-Bold",  fontSize=11, textColor=NAVY,        spaceBefore=4, spaceAfter=3)
S_H3        = make_style("H3",       fontName="Helvetica-Bold",  fontSize=9.5,textColor=TEAL,        spaceBefore=3, spaceAfter=2)
S_BODY      = make_style("Body2",    fontName="Helvetica",       fontSize=8.5,textColor=GREY_DARK,   spaceAfter=2, leading=12)
S_BULLET    = make_style("Bullet2",  fontName="Helvetica",       fontSize=8,  textColor=GREY_DARK,   leftIndent=12, bulletIndent=4, spaceAfter=1, leading=11)
S_CAPTION   = make_style("Caption2", fontName="Helvetica-Oblique",fontSize=7.5,textColor=GREY_MID,   alignment=TA_CENTER, spaceAfter=2)
S_LABEL     = make_style("Label2",   fontName="Helvetica-Bold",  fontSize=8,  textColor=WHITE,       alignment=TA_CENTER)
S_TABLE_H   = make_style("TH",       fontName="Helvetica-Bold",  fontSize=8,  textColor=WHITE,       alignment=TA_CENTER)
S_TABLE_B   = make_style("TB",       fontName="Helvetica",       fontSize=7.5,textColor=GREY_DARK,   alignment=TA_CENTER)
S_TABLE_BL  = make_style("TBL",      fontName="Helvetica",       fontSize=7.5,textColor=GREY_DARK,   alignment=TA_LEFT)
S_NOTE      = make_style("Note",     fontName="Helvetica-Oblique",fontSize=7.5,textColor=GREY_DARK,  spaceAfter=2)
S_BOX_TITLE = make_style("BoxTitle", fontName="Helvetica-Bold",  fontSize=9,  textColor=WHITE,       alignment=TA_CENTER)
S_BOX_BODY  = make_style("BoxBody",  fontName="Helvetica",       fontSize=8,  textColor=GREY_DARK,   leading=11)
S_STEP_NUM  = make_style("StepNum",  fontName="Helvetica-Bold",  fontSize=16, textColor=WHITE,       alignment=TA_CENTER)
S_STEP_TXT  = make_style("StepTxt",  fontName="Helvetica-Bold",  fontSize=9,  textColor=NAVY,        spaceAfter=1)


# ── Custom Flowables ─────────────────────────────────────────────────────────

class ColorBanner(Flowable):
    """Full-width colored banner with title and subtitle."""
    def __init__(self, title, subtitle="", bg=NAVY, height=55*mm):
        super().__init__()
        self.title = title
        self.subtitle = subtitle
        self.bg = bg
        self.bh = height
        self.width = PAGE_W - 2*cm

    def wrap(self, aw, ah):
        self.width = aw
        return (aw, self.bh)

    def draw(self):
        c = self.canv
        w, h = self.width, self.bh
        # Background
        c.setFillColor(self.bg)
        c.roundRect(0, 0, w, h, 8, fill=1, stroke=0)
        # Decorative circles
        c.setFillColor(colors.HexColor("#FFFFFF20"))
        c.circle(w - 30, h - 20, 40, fill=1, stroke=0)
        c.circle(w - 60, 10, 25, fill=1, stroke=0)
        c.circle(20, h + 5, 30, fill=1, stroke=0)
        # Title
        c.setFillColor(WHITE)
        c.setFont("Helvetica-Bold", 20)
        c.drawCentredString(w/2, h - 28, self.title)
        # Subtitle
        if self.subtitle:
            c.setFillColor(CYAN_LIGHT)
            c.setFont("Helvetica", 10)
            c.drawCentredString(w/2, h - 44, self.subtitle)
        # Bottom accent line
        c.setStrokeColor(TEAL)
        c.setLineWidth(2)
        c.line(w*0.2, 8, w*0.8, 8)


class SectionHeader(Flowable):
    """Colored section header bar."""
    def __init__(self, text, bg=TEAL, text_color=WHITE, height=10*mm):
        super().__init__()
        self.text = text
        self.bg = bg
        self.text_color = text_color
        self.bh = height

    def wrap(self, aw, ah):
        self.width = aw
        return (aw, self.bh)

    def draw(self):
        c = self.canv
        w, h = self.width, self.bh
        c.setFillColor(self.bg)
        c.roundRect(0, 0, w, h, 5, fill=1, stroke=0)
        c.setFillColor(self.text_color)
        c.setFont("Helvetica-Bold", 11)
        c.drawString(10, h/2 - 4, self.text)


class StepBox(Flowable):
    """Numbered step box with title and bullet items."""
    def __init__(self, number, title, bullets, bg=BLUE_LIGHT, accent=BLUE_MID, width=None, height=None):
        super().__init__()
        self.number = number
        self.title = title
        self.bullets = bullets
        self.bg = bg
        self.accent = accent
        self._width = width or 85*mm
        self._height = height or 55*mm

    def wrap(self, aw, ah):
        return (self._width, self._height)

    def draw(self):
        c = self.canv
        w, h = self._width, self._height
        # Background
        c.setFillColor(self.bg)
        c.roundRect(0, 0, w, h, 6, fill=1, stroke=0)
        # Accent left bar
        c.setFillColor(self.accent)
        c.roundRect(0, 0, 6, h, 6, fill=1, stroke=0)
        c.rect(3, 0, 3, h, fill=1, stroke=0)  # square right side of bar
        # Step circle
        c.setFillColor(self.accent)
        c.circle(22, h - 16, 12, fill=1, stroke=0)
        c.setFillColor(WHITE)
        c.setFont("Helvetica-Bold", 13)
        c.drawCentredString(22, h - 20, str(self.number))
        # Title
        c.setFillColor(NAVY)
        c.setFont("Helvetica-Bold", 9.5)
        c.drawString(40, h - 20, self.title)
        # Divider
        c.setStrokeColor(self.accent)
        c.setLineWidth(0.5)
        c.line(12, h - 28, w - 8, h - 28)
        # Bullets
        c.setFillColor(GREY_DARK)
        c.setFont("Helvetica", 7.5)
        y = h - 40
        for b in self.bullets:
            # Bullet dot
            c.setFillColor(self.accent)
            c.circle(20, y + 2.5, 2, fill=1, stroke=0)
            c.setFillColor(GREY_DARK)
            # Text wrapping
            max_chars = int((w - 36) / 4.3)
            words = b.split()
            line = ""
            first = True
            for word in words:
                test = (line + " " + word).strip()
                if len(test) <= max_chars:
                    line = test
                else:
                    c.drawString(26, y, line)
                    y -= 10
                    line = word
                    first = False
            if line:
                c.drawString(26, y, line)
                y -= 11
            if y < 8:
                break


class ArrowDiagram(Flowable):
    """Horizontal flow arrow diagram for transcription steps."""
    def __init__(self, steps, colors_list, width=None, height=22*mm):
        super().__init__()
        self.steps = steps
        self.colors_list = colors_list
        self._width = width or PAGE_W - 2*cm
        self._height = height

    def wrap(self, aw, ah):
        self._width = aw
        return (aw, self._height)

    def draw(self):
        c = self.canv
        n = len(self.steps)
        w, h = self._width, self._height
        box_w = (w - (n-1)*8) / n
        bh = h - 4

        for i, (step, col) in enumerate(zip(self.steps, self.colors_list)):
            x = i * (box_w + 8)
            # Chevron shape
            if i < n - 1:
                # Draw arrow shape
                pts = [
                    x, bh,
                    x + box_w - 6, bh,
                    x + box_w + 2, bh/2,
                    x + box_w - 6, 0,
                    x, 0,
                    x + 6, bh/2,
                ]
                if i == 0:
                    pts = [
                        x, bh,
                        x + box_w - 6, bh,
                        x + box_w + 2, bh/2,
                        x + box_w - 6, 0,
                        x, 0,
                    ]
                c.setFillColor(col)
                p = c.beginPath()
                p.moveTo(pts[0], pts[1])
                for j in range(2, len(pts), 2):
                    p.lineTo(pts[j], pts[j+1])
                p.close()
                c.drawPath(p, fill=1, stroke=0)
            else:
                c.setFillColor(col)
                c.roundRect(x, 0, box_w, bh, 4, fill=1, stroke=0)

            # Text
            c.setFillColor(WHITE)
            c.setFont("Helvetica-Bold", 7.5)
            txt_x = x + box_w/2 + (3 if i > 0 else 0)
            lines = step.split("\n")
            start_y = bh/2 + (len(lines)-1) * 5
            for li, ln in enumerate(lines):
                c.drawCentredString(txt_x, start_y - li*10, ln)


class ComparisonTable(Flowable):
    """Side-by-side comparison panel."""
    def __init__(self, headers, rows, col_colors, width=None, height=None):
        super().__init__()
        self.headers = headers
        self.rows = rows
        self.col_colors = col_colors
        self._width = width
        self._height = height

    def wrap(self, aw, ah):
        self._width = self._width or aw
        return (self._width, self._height or 60*mm)

    def draw(self):
        c = self.canv
        w = self._width
        n_cols = len(self.headers)
        col_w = w / n_cols
        row_h = 14
        header_h = 16

        # Header row
        for i, (hdr, col) in enumerate(zip(self.headers, self.col_colors)):
            c.setFillColor(col)
            c.rect(i * col_w, self._height - header_h, col_w, header_h, fill=1, stroke=0)
            c.setFillColor(WHITE)
            c.setFont("Helvetica-Bold", 8)
            c.drawCentredString(i * col_w + col_w/2, self._height - header_h + 5, hdr)

        # Data rows
        for r, row in enumerate(self.rows):
            y = self._height - header_h - (r+1) * row_h
            bg = GREY_LIGHT if r % 2 == 0 else WHITE
            c.setFillColor(bg)
            c.rect(0, y, w, row_h, fill=1, stroke=0)
            for ci, cell in enumerate(row):
                is_feature = (ci == 0)
                c.setFillColor(GREY_DARK if not is_feature else NAVY)
                c.setFont("Helvetica-Bold" if is_feature else "Helvetica", 7.2)
                # Left-align feature column, center others
                if is_feature:
                    c.drawString(ci * col_w + 4, y + 4, cell)
                else:
                    c.drawCentredString(ci * col_w + col_w/2, y + 4, cell)
            # Row border
            c.setStrokeColor(GREY_LIGHT)
            c.setLineWidth(0.3)
            c.line(0, y, w, y)

        # Outer border
        c.setStrokeColor(GREY_MID)
        c.setLineWidth(0.7)
        c.rect(0, self._height - header_h - len(self.rows)*row_h,
               w, header_h + len(self.rows)*row_h, fill=0, stroke=1)


class ModBox(Flowable):
    """Colored modification card."""
    def __init__(self, number, title, subtitle, points, bg, accent, width=None, height=50*mm):
        super().__init__()
        self.number = number
        self.title = title
        self.subtitle = subtitle
        self.points = points
        self.bg = bg
        self.accent = accent
        self._width = width or 85*mm
        self._height = height

    def wrap(self, aw, ah):
        if self._width is None:
            self._width = aw
        return (self._width, self._height)

    def draw(self):
        c = self.canv
        w, h = self._width, self._height
        # Background card
        c.setFillColor(self.bg)
        c.roundRect(0, 0, w, h, 7, fill=1, stroke=0)
        # Top accent bar
        c.setFillColor(self.accent)
        c.roundRect(0, h - 22, w, 22, 7, fill=1, stroke=0)
        c.rect(0, h - 22, w, 11, fill=1, stroke=0)
        # Number badge
        c.setFillColor(WHITE)
        c.setFillColorRGB(1, 1, 1, alpha=0.25)
        c.circle(18, h - 11, 10, fill=1, stroke=0)
        c.setFillColor(WHITE)
        c.setFont("Helvetica-Bold", 12)
        c.drawCentredString(18, h - 15, str(self.number))
        # Title
        c.setFillColor(WHITE)
        c.setFont("Helvetica-Bold", 9)
        c.drawString(32, h - 15, self.title)
        # Subtitle
        c.setFillColor(self.accent)
        c.setFont("Helvetica-Oblique", 7.5)
        c.drawString(10, h - 32, self.subtitle)
        # Divider
        c.setStrokeColor(self.accent)
        c.setLineWidth(0.5)
        c.line(8, h - 36, w - 8, h - 36)
        # Points
        c.setFont("Helvetica", 7.5)
        y = h - 46
        for pt in self.points:
            c.setFillColor(self.accent)
            c.circle(14, y + 2.5, 2.5, fill=1, stroke=0)
            c.setFillColor(GREY_DARK)
            max_chars = int((w - 30) / 4.3)
            words = pt.split()
            line = ""
            for word in words:
                test = (line + " " + word).strip()
                if len(test) <= max_chars:
                    line = test
                else:
                    c.drawString(21, y, line)
                    y -= 10
                    line = word
            if line:
                c.drawString(21, y, line)
                y -= 11
            if y < 8:
                break


class DNADiagram(Flowable):
    """Simple ASCII-art style DNA-to-mRNA transcription diagram."""
    def __init__(self, width=None, height=48*mm):
        super().__init__()
        self._width = width
        self._height = height

    def wrap(self, aw, ah):
        if self._width is None:
            self._width = aw
        return (self._width, self._height)

    def draw(self):
        c = self.canv
        w, h = self._width, self._height
        mid = w / 2
        # DNA double helix representation (simplified)
        # Top strand label
        c.setFillColor(NAVY)
        c.setFont("Helvetica-Bold", 8)
        c.drawString(8, h - 12, "5'")
        c.drawString(w - 16, h - 12, "3'")
        c.setFont("Helvetica", 7)
        c.setFillColor(GREY_DARK)
        c.drawCentredString(mid, h - 12, "Non-template (coding) strand  5' → 3'")

        # Draw DNA strands
        strand_y1 = h - 22
        strand_y2 = h - 34
        c.setStrokeColor(NAVY)
        c.setLineWidth(2.5)
        c.line(30, strand_y1, w - 30, strand_y1)
        c.setStrokeColor(TEAL)
        c.setLineWidth(2.5)
        c.line(30, strand_y2, w - 30, strand_y2)

        # Base pairs
        c.setStrokeColor(GREY_MID)
        c.setLineWidth(0.8)
        for i in range(8):
            bx = 40 + i * (w - 80) / 7
            c.line(bx, strand_y1, bx, strand_y2)

        # Labels on strands
        c.setFillColor(NAVY)
        c.setFont("Helvetica-Bold", 7.5)
        c.drawString(8, strand_y1 - 3, "")
        c.setFillColor(TEAL)
        c.drawString(8, strand_y2 - 3, "")

        c.setFillColor(GREY_DARK)
        c.setFont("Helvetica", 7)
        c.drawCentredString(mid, strand_y2 - 9, "Template (antisense) strand  3' → 5'")

        # Arrow down
        c.setStrokeColor(ORANGE_MID)
        c.setFillColor(ORANGE_MID)
        c.setLineWidth(1.5)
        arrow_x = mid
        c.line(arrow_x, strand_y2 - 18, arrow_x, strand_y2 - 28)
        # Arrowhead
        c.beginPath()
        c.moveTo(arrow_x - 5, strand_y2 - 25)
        c.lineTo(arrow_x + 5, strand_y2 - 25)
        c.lineTo(arrow_x, strand_y2 - 32)
        c.closePath()
        c.fill()

        # RNA pol label
        c.setFillColor(ORANGE_MID)
        c.setFont("Helvetica-Bold", 8)
        c.drawString(arrow_x + 8, strand_y2 - 22, "RNA Polymerase")

        # mRNA strand
        mrna_y = strand_y2 - 42
        c.setStrokeColor(RED_MID)
        c.setLineWidth(2.5)
        c.line(30, mrna_y, w - 30, mrna_y)
        c.setFillColor(RED_MID)
        c.setFont("Helvetica-Bold", 7.5)
        c.drawString(8, mrna_y - 3, "5'")
        c.drawString(w - 22, mrna_y - 3, "3'")
        c.setFont("Helvetica", 7)
        c.setFillColor(GREY_DARK)
        c.drawCentredString(mid, mrna_y - 10, "Primary RNA transcript (mRNA)  5' → 3'")


# ── Document Build ────────────────────────────────────────────────────────────

def build_pdf(path):
    doc = SimpleDocTemplate(
        path,
        pagesize=A4,
        leftMargin=1.5*cm,
        rightMargin=1.5*cm,
        topMargin=1.2*cm,
        bottomMargin=1.2*cm,
        title="Transcription Visual Study Guide",
        author="Orris Medical",
    )

    story = []
    usable_w = PAGE_W - 3*cm

    # ── PAGE 1: COVER / OVERVIEW ───────────────────────────────────────────
    story.append(ColorBanner(
        "TRANSCRIPTION",
        "Visual Study Guide  |  Prokaryotes & Eukaryotes  |  Post-Transcriptional Modifications",
        bg=NAVY,
        height=52*mm
    ))
    story.append(Spacer(1, 5*mm))

    # Big overview flow diagram
    story.append(SectionHeader("  Overview: Flow of Genetic Information", bg=TEAL))
    story.append(Spacer(1, 3*mm))
    steps_overview = ["DNA\nTemplate", "RNA Poly-\nmerase Binds", "Initiation", "Elongation",
                      "Termination", "Primary\nTranscript", "Post-Tx\nModification", "Mature\nmRNA"]
    cols_overview  = [NAVY, TEAL, BLUE_MID, GREEN_MID, PURPLE_MID, ORANGE_MID, PINK_MID, RED_MID]
    story.append(ArrowDiagram(steps_overview, cols_overview, height=20*mm))
    story.append(Spacer(1, 3*mm))

    # DNA diagram
    story.append(DNADiagram(height=42*mm))
    story.append(Spacer(1, 4*mm))

    # Key facts box
    story.append(SectionHeader("  Key Concepts at a Glance", bg=GREY_DARK))
    story.append(Spacer(1, 3*mm))
    key_data = [
        [Paragraph("<b>Definition</b>", S_TABLE_H),
         Paragraph("Synthesis of RNA from a DNA template by RNA polymerase. RNA is made 5'→3', template read 3'→5'.", S_TABLE_BL)],
        [Paragraph("<b>Template strand</b>", S_TABLE_H),
         Paragraph("Antisense/noncoding strand (read 3'→5'). Coding strand = sense strand = same sequence as mRNA (T→U).", S_TABLE_BL)],
        [Paragraph("<b>Substrate</b>", S_TABLE_H),
         Paragraph("Ribonucleoside triphosphates (ATP, GTP, CTP, UTP). Each addition releases pyrophosphate.", S_TABLE_BL)],
        [Paragraph("<b>Primer?</b>", S_TABLE_H),
         Paragraph("None required. RNA pol starts de novo (unlike DNA pol which needs a primer).", S_TABLE_BL)],
        [Paragraph("<b>Proofreading?</b>", S_TABLE_H),
         Paragraph("No 3'→5' exonuclease activity. Higher error rate than replication. RNA pol pauses and backtracks on misincorporation.", S_TABLE_BL)],
    ]
    key_table = Table(key_data, colWidths=[3.5*cm, usable_w - 3.5*cm])
    key_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (0, -1), NAVY),
        ("BACKGROUND", (1, 0), (1, -1), WHITE),
        ("ROWBACKGROUNDS", (1, 0), (1, -1), [GREY_LIGHT, WHITE]),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 5),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
        ("GRID", (0, 0), (-1, -1), 0.4, GREY_MID),
        ("ROUNDEDCORNERS", [4]),
    ]))
    story.append(key_table)
    story.append(PageBreak())

    # ── PAGE 2: PROKARYOTIC TRANSCRIPTION ─────────────────────────────────
    story.append(ColorBanner("PROKARYOTIC TRANSCRIPTION",
                              "E. coli model | Single RNA Polymerase | No nuclear envelope",
                              bg=TEAL, height=38*mm))
    story.append(Spacer(1, 4*mm))

    # RNA Pol info
    story.append(SectionHeader("  RNA Polymerase Structure", bg=TEAL))
    story.append(Spacer(1, 3*mm))
    pol_data = [
        [Paragraph("<b>Form</b>", S_TABLE_H),
         Paragraph("<b>Subunits</b>", S_TABLE_H),
         Paragraph("<b>Function</b>", S_TABLE_H)],
        [Paragraph("Core Enzyme", S_TABLE_B),
         Paragraph("2α + β + β' + ω", S_TABLE_B),
         Paragraph("Template binding (β'), polymerase activity (β), assembly (α, ω). Cannot recognize promoter alone.", S_TABLE_BL)],
        [Paragraph("Holoenzyme", S_TABLE_B),
         Paragraph("Core + σ (sigma) factor", S_TABLE_B),
         Paragraph("σ factor enables promoter recognition. σ70 is the predominant sigma factor. After initiation, σ is released.", S_TABLE_BL)],
    ]
    pol_table = Table(pol_data, colWidths=[3*cm, 4*cm, usable_w - 7*cm])
    pol_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), NAVY),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [BLUE_LIGHT, CYAN_LIGHT]),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 5), ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 5),
        ("GRID", (0, 0), (-1, -1), 0.4, GREY_MID),
    ]))
    story.append(pol_table)
    story.append(Spacer(1, 4*mm))

    # Three steps
    story.append(SectionHeader("  Steps of Prokaryotic Transcription", bg=TEAL))
    story.append(Spacer(1, 3*mm))

    half_w = (usable_w - 4*mm) / 2
    third_w = (usable_w - 8*mm) / 3

    step1 = StepBox(1, "INITIATION",
        ["Holoenzyme binds promoter region (not transcribed)",
         "-35 sequence (TTGACA): initial contact, closed complex forms",
         "Pribnow box / -10 sequence (TATAAT): DNA melts ~14 bp",
         "Open complex (transcription bubble) forms",
         "Short RNA fragments made & discarded until >10 nt",
         "σ factor released; core enzyme clears promoter"],
        bg=BLUE_LIGHT, accent=BLUE_MID, width=third_w, height=62*mm)

    step2 = StepBox(2, "ELONGATION",
        ["Core enzyme moves along template strand 3'→5'",
         "NTPs added sequentially, RNA grows 5'→3'",
         "Short DNA-RNA hybrid helix maintained in bubble",
         "Topoisomerases relieve supercoiling ahead of pol",
         "No primer needed; no proofreading (3'→5' exonuclease)",
         "Misincorporation causes pol to pause & backtrack"],
        bg=GREEN_LIGHT, accent=GREEN_MID, width=third_w, height=62*mm)

    step3 = StepBox(3, "TERMINATION",
        ["Rho-independent: GC-rich hairpin + poly-U tail",
         "Hairpin in nascent RNA destabilizes transcription complex",
         "Weak U:A base pairs facilitate RNA release",
         "Rho-dependent: ρ protein (hexameric ATPase/helicase)",
         "ρ binds rut site, chases polymerase, unwinds hybrid",
         "RNA transcript released from DNA"],
        bg=PURPLE_LIGHT, accent=PURPLE_MID, width=third_w, height=62*mm)

    steps_row = Table([[step1, Spacer(4*mm, 1), step2, Spacer(4*mm, 1), step3]],
                      colWidths=[third_w, 4*mm, third_w, 4*mm, third_w])
    steps_row.setStyle(TableStyle([("VALIGN", (0,0), (-1,-1), "TOP"), ("TOPPADDING", (0,0),(-1,-1),0), ("LEFTPADDING",(0,0),(-1,-1),0)]))
    story.append(steps_row)
    story.append(Spacer(1, 4*mm))

    # Promoter info
    story.append(SectionHeader("  Prokaryotic Promoter Elements", bg=NAVY))
    story.append(Spacer(1, 3*mm))

    prom_data = [
        [Paragraph("<b>Element</b>", S_TABLE_H),
         Paragraph("<b>Position</b>", S_TABLE_H),
         Paragraph("<b>Consensus Sequence</b>", S_TABLE_H),
         Paragraph("<b>Function</b>", S_TABLE_H)],
        [Paragraph("-35 Sequence", S_TABLE_B),
         Paragraph("~35 bp upstream", S_TABLE_B),
         Paragraph("5'-TTGACA-3'", S_TABLE_B),
         Paragraph("Initial holoenzyme docking; closed complex", S_TABLE_BL)],
        [Paragraph("Pribnow Box", S_TABLE_B),
         Paragraph("~10 bp upstream", S_TABLE_B),
         Paragraph("5'-TATAAT-3'", S_TABLE_B),
         Paragraph("DNA melting site; open complex (transcription bubble)", S_TABLE_BL)],
        [Paragraph("Start site", S_TABLE_B),
         Paragraph("+1", S_TABLE_B),
         Paragraph("Usually a purine", S_TABLE_B),
         Paragraph("First nucleotide incorporated into RNA transcript", S_TABLE_BL)],
    ]
    prom_table = Table(prom_data, colWidths=[3*cm, 3*cm, 4*cm, usable_w - 10*cm])
    prom_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), NAVY),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [CYAN_LIGHT, WHITE]),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 5), ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 5),
        ("GRID", (0, 0), (-1, -1), 0.4, GREY_MID),
    ]))
    story.append(prom_table)
    story.append(Spacer(1, 4*mm))

    # Antibiotic note
    antibiotic_data = [[
        Paragraph("ANTIBIOTIC TARGETS", S_BOX_TITLE),
        Paragraph(
            "<b>Rifampin (Rifampicin):</b> Binds β subunit of prokaryotic RNA pol → blocks chain elongation beyond 3 nt. "
            "Key drug in tuberculosis treatment.<br/>"
            "<b>Actinomycin D (Dactinomycin):</b> Intercalates between DNA bases → inhibits both initiation and elongation. Used in tumour chemotherapy.",
            S_BOX_BODY)
    ]]
    atab = Table(antibiotic_data, colWidths=[4.5*cm, usable_w - 4.5*cm])
    atab.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (0, 0), RED_MID),
        ("BACKGROUND", (1, 0), (1, 0), RED_LIGHT),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 7), ("BOTTOMPADDING", (0, 0), (-1, -1), 7),
        ("LEFTPADDING", (0, 0), (-1, -1), 7),
        ("ROUNDEDCORNERS", [5]),
        ("BOX", (0, 0), (-1, -1), 0.5, RED_MID),
    ]))
    story.append(atab)
    story.append(PageBreak())

    # ── PAGE 3: EUKARYOTIC TRANSCRIPTION ──────────────────────────────────
    story.append(ColorBanner("EUKARYOTIC TRANSCRIPTION",
                              "Three RNA Polymerases | Transcription Factors | Occurs in Nucleus",
                              bg=PURPLE_MID, height=38*mm))
    story.append(Spacer(1, 4*mm))

    # Three RNA Pols
    story.append(SectionHeader("  Three Nuclear RNA Polymerases", bg=PURPLE_MID))
    story.append(Spacer(1, 3*mm))

    rpol_data = [
        [Paragraph("<b>Enzyme</b>", S_TABLE_H),
         Paragraph("<b>Location</b>", S_TABLE_H),
         Paragraph("<b>Products</b>", S_TABLE_H),
         Paragraph("<b>Inhibitor</b>", S_TABLE_H)],
        [Paragraph("RNA Pol I", S_TABLE_B),
         Paragraph("Nucleolus", S_TABLE_B),
         Paragraph("28S, 18S, 5.8S rRNA (~80% of all cellular RNA)", S_TABLE_BL),
         Paragraph("Not α-amanitin sensitive", S_TABLE_B)],
        [Paragraph("RNA Pol II", S_TABLE_B),
         Paragraph("Nucleoplasm", S_TABLE_B),
         Paragraph("hnRNA (pre-mRNA), snRNA — all protein-coding genes", S_TABLE_BL),
         Paragraph("α-Amanitin (high sensitivity)", S_TABLE_B)],
        [Paragraph("RNA Pol III", S_TABLE_B),
         Paragraph("Nucleoplasm", S_TABLE_B),
         Paragraph("tRNA, 5S rRNA, some snRNA & snoRNA", S_TABLE_BL),
         Paragraph("α-Amanitin (low sensitivity)", S_TABLE_B)],
    ]
    rpol_table = Table(rpol_data, colWidths=[2.8*cm, 2.8*cm, usable_w - 9*cm, 4*cm])
    rpol_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), PURPLE_MID),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [PURPLE_LIGHT, WHITE]),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 5), ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 5),
        ("GRID", (0, 0), (-1, -1), 0.4, GREY_MID),
    ]))
    story.append(rpol_table)
    story.append(Spacer(1, 4*mm))

    # Steps eukaryotic
    story.append(SectionHeader("  Steps of Eukaryotic Transcription (RNA Pol II)", bg=PURPLE_MID))
    story.append(Spacer(1, 3*mm))

    e_step1 = StepBox(1, "CHROMATIN REMODELING",
        ["Transcribed genes in euchromatin (decondensed)",
         "HATs (histone acetyltransferases) acetylate histone lysines",
         "Acetylation reduces histone-DNA affinity, opens chromatin",
         "HDACs reverse this: restore positive charge, condense chromatin",
         "ATP-dependent nucleosome repositioning also required"],
        bg=ORANGE_LIGHT, accent=ORANGE_MID, width=third_w, height=60*mm)

    e_step2 = StepBox(2, "INITIATION",
        ["General TFs (TFIIA, B, D, E, F, H) assemble at core promoter",
         "TFIID (TBP subunit) binds TATA box first",
         "Other GTFs and RNA Pol II join sequentially",
         "TFIIH phosphorylates CTD of RNA Pol II",
         "Promoter escape occurs; pol clears the promoter",
         "Enhancers + specific TFs increase transcription rate via DNA looping"],
        bg=BLUE_LIGHT, accent=BLUE_MID, width=third_w, height=60*mm)

    e_step3 = StepBox(3, "ELONGATION & TERMINATION",
        ["DNA locally unwound; RNA synthesized 5'→3'",
         "5' cap added co-transcriptionally as RNA emerges",
         "Entire gene (exons + introns) transcribed = pre-mRNA/hnRNA",
         "Termination linked to polyadenylation signal (AAUAAA)",
         "Pre-mRNA cleaved downstream of signal",
         "Poly-A tail added; pol terminates at variable downstream site"],
        bg=GREEN_LIGHT, accent=GREEN_MID, width=third_w, height=60*mm)

    e_steps_row = Table([[e_step1, Spacer(4*mm, 1), e_step2, Spacer(4*mm, 1), e_step3]],
                        colWidths=[third_w, 4*mm, third_w, 4*mm, third_w])
    e_steps_row.setStyle(TableStyle([("VALIGN", (0,0),(-1,-1),"TOP"),("TOPPADDING",(0,0),(-1,-1),0),("LEFTPADDING",(0,0),(-1,-1),0)]))
    story.append(e_steps_row)
    story.append(Spacer(1, 4*mm))

    # Core promoter elements
    story.append(SectionHeader("  Eukaryotic Core Promoter Elements (RNA Pol II)", bg=NAVY))
    story.append(Spacer(1, 3*mm))
    ep_data = [
        [Paragraph("<b>Element</b>", S_TABLE_H),
         Paragraph("<b>Position</b>", S_TABLE_H),
         Paragraph("<b>Consensus</b>", S_TABLE_H),
         Paragraph("<b>Notes</b>", S_TABLE_H)],
        [Paragraph("TATA box (Hogness box)", S_TABLE_B),
         Paragraph("~-25", S_TABLE_B),
         Paragraph("TATA(A/T)A", S_TABLE_B),
         Paragraph("Found in ~12.5% of eukaryotic promoters. Bound by TBP (subunit of TFIID).", S_TABLE_BL)],
        [Paragraph("BRE (TFIIB recognition)", S_TABLE_B),
         Paragraph("~-35 to -30", S_TABLE_B),
         Paragraph("GC-rich", S_TABLE_B),
         Paragraph("Bound by TFIIB. Helps determine transcription direction.", S_TABLE_BL)],
        [Paragraph("Initiator (Inr)", S_TABLE_B),
         Paragraph("+1", S_TABLE_B),
         Paragraph("PyPyA+1NPyPy", S_TABLE_B),
         Paragraph("Spans transcription start site; present in TATA-less promoters.", S_TABLE_BL)],
        [Paragraph("DPE (Downstream)", S_TABLE_B),
         Paragraph("+28 to +34", S_TABLE_B),
         Paragraph("AGCG", S_TABLE_B),
         Paragraph("Works with Inr in TATA-less promoters. Bound by TAF subunits of TFIID.", S_TABLE_BL)],
    ]
    ep_table = Table(ep_data, colWidths=[4*cm, 2.5*cm, 3*cm, usable_w - 9.5*cm])
    ep_table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), NAVY),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [PURPLE_LIGHT, WHITE]),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 5), ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 5),
        ("GRID", (0, 0), (-1, -1), 0.4, GREY_MID),
    ]))
    story.append(ep_table)
    story.append(PageBreak())

    # ── PAGE 4: POST-TRANSCRIPTIONAL MODIFICATIONS ────────────────────────
    story.append(ColorBanner("POST-TRANSCRIPTIONAL MODIFICATIONS",
                              "Eukaryotes only (mRNA)  |  All occur in the nucleus  |  hnRNA → Mature mRNA",
                              bg=GREEN_DARK, height=38*mm))
    story.append(Spacer(1, 4*mm))

    # Flow: hnRNA to mRNA
    story.append(SectionHeader("  Processing Pathway: hnRNA → Mature mRNA", bg=GREEN_DARK))
    story.append(Spacer(1, 3*mm))
    ptm_steps = ["Pre-mRNA\n(hnRNA)", "5' Capping\n(co-Tx)", "3' Poly-A\nTail", "RNA Splicing\n(Spliceosome)", "Mature\nmRNA", "Nuclear\nExport", "Translation\n(Cytoplasm)"]
    ptm_cols  = [TEAL, BLUE_MID, ORANGE_MID, PURPLE_MID, GREEN_MID, NAVY, RED_MID]
    story.append(ArrowDiagram(ptm_steps, ptm_cols, height=20*mm))
    story.append(Spacer(1, 4*mm))

    # Four modification cards
    mod_w = (usable_w - 6*mm) / 2

    mod1 = ModBox(1, "5' CAPPING",
        "Occurs co-transcriptionally as 5' end emerges",
        ["Terminal 5'-triphosphate loses one phosphate",
         "Guanylyltransferase adds GMP via 5'-to-5' triphosphate linkage",
         "Methyltransferase adds CH3 at N7 of guanine using SAM",
         "Result: 7-methylguanosine (m7G) cap",
         "Additional 2'-O-methylations: Cap 0, Cap 1, Cap 2",
         "Functions: protects mRNA from 5' exonucleases, required for translation initiation (eIF4E binding), aids nuclear export"],
        bg=BLUE_LIGHT, accent=BLUE_MID, width=mod_w, height=72*mm)

    mod2 = ModBox(2, "3' POLYADENYLATION",
        "Poly-A tail of 40-250 adenylates added to 3' end",
        ["Polyadenylation signal: AAUAAA (or variant) near 3' end",
         "Pre-mRNA cleaved ~10-30 nt downstream of signal",
         "Polyadenylate polymerase adds AMP residues using ATP",
         "Poly-A tail NOT encoded in DNA — added post-transcriptionally",
         "Histone mRNAs are the major exception (no poly-A tail)",
         "Functions: stability (protects from 3' exonucleases), nuclear export, translation efficiency"],
        bg=ORANGE_LIGHT, accent=ORANGE_MID, width=mod_w, height=72*mm)

    mod3 = ModBox(3, "RNA SPLICING",
        "Introns removed; exons joined by the spliceosome",
        ["Spliceosome = 5 snRNPs: U1, U2, U4, U5, U6",
         "U1 binds 5' splice site (GU at intron start)",
         "U2 binds branch point adenosine within intron",
         "2'-OH of branch A attacks 5' splice site → lariat intermediate",
         "Freed exon 3'-OH attacks 3' splice site (AG) → exons join",
         "Lariat intron excised and degraded",
         "Alternative splicing: multiple isoforms from one gene"],
        bg=PURPLE_LIGHT, accent=PURPLE_MID, width=mod_w, height=72*mm)

    mod4 = ModBox(4, "tRNA & rRNA PROCESSING",
        "Both prokaryotes and eukaryotes modify tRNA and rRNA",
        ["tRNA precursors (~100 nt) cleaved by RNase P (5' end)",
         "CCA triplet added to 3' end by nucleotidyltransferase",
         "Introns (anticodon loop) removed by endonucleases + RNA ligase",
         "Modified bases: dihydrouracil (D), pseudouridine (Ψ), ribothymidine (T), inosine",
         "rRNA: single 45S pre-rRNA → 28S + 18S + 5.8S (eukaryotes)",
         "Processed in nucleolus; snoRNAs guide base/ribose methylations"],
        bg=RED_LIGHT, accent=RED_MID, width=mod_w, height=72*mm)

    mods_row1 = Table([[mod1, Spacer(6*mm, 1), mod2]],
                      colWidths=[mod_w, 6*mm, mod_w])
    mods_row1.setStyle(TableStyle([("VALIGN",(0,0),(-1,-1),"TOP"),("TOPPADDING",(0,0),(-1,-1),0),("LEFTPADDING",(0,0),(-1,-1),0)]))
    story.append(mods_row1)
    story.append(Spacer(1, 4*mm))
    mods_row2 = Table([[mod3, Spacer(6*mm, 1), mod4]],
                      colWidths=[mod_w, 6*mm, mod_w])
    mods_row2.setStyle(TableStyle([("VALIGN",(0,0),(-1,-1),"TOP"),("TOPPADDING",(0,0),(-1,-1),0),("LEFTPADDING",(0,0),(-1,-1),0)]))
    story.append(mods_row2)
    story.append(Spacer(1, 4*mm))

    # Clinical note
    clin_data = [[
        Paragraph("CLINICAL RELEVANCE", S_BOX_TITLE),
        Paragraph(
            "<b>Vitamins B12 & Folate:</b> Required for SAM regeneration; their deficiency impairs 5' capping (mRNA methylation).<br/>"
            "<b>α-Amanitin poisoning:</b> Death cap mushroom toxin inhibits RNA Pol II → no mRNA synthesis → hepatocellular failure.<br/>"
            "<b>Splicing mutations:</b> ~15% of point mutations causing genetic disease affect splice sites, leading to exon skipping or intron retention.",
            S_BOX_BODY)
    ]]
    ctab = Table(clin_data, colWidths=[4.5*cm, usable_w - 4.5*cm])
    ctab.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (0, 0), GREEN_DARK),
        ("BACKGROUND", (1, 0), (1, 0), GREEN_LIGHT),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 7), ("BOTTOMPADDING", (0, 0), (-1, -1), 7),
        ("LEFTPADDING", (0, 0), (-1, -1), 7),
        ("BOX", (0, 0), (-1, -1), 0.5, GREEN_MID),
    ]))
    story.append(ctab)
    story.append(PageBreak())

    # ── PAGE 5: COMPARISON TABLE ──────────────────────────────────────────
    story.append(ColorBanner("PROKARYOTES vs EUKARYOTES",
                              "Side-by-Side Comparison of Transcription",
                              bg=NAVY, height=35*mm))
    story.append(Spacer(1, 5*mm))

    comp_headers = ["Feature", "PROKARYOTES", "EUKARYOTES"]
    comp_rows = [
        ["RNA polymerase", "Single (core + σ)", "3 nuclear RNA Pols (I, II, III)"],
        ["Sigma / TFs", "σ factor for promoter recognition", "Multiple GTFs (TFIIA-H) + STFs"],
        ["Promoter (-35)", "TTGACA (~-35)", "Not conserved; upstream enhancers"],
        ["Promoter (-10)", "TATAAT (Pribnow box)", "TATA box ~-25 (only 12.5% of genes)"],
        ["Transcription site", "Cytoplasm (no nucleus)", "Nucleus"],
        ["Coupled translation?", "YES - simultaneous", "NO - separated by nuclear envelope"],
        ["Primary transcript", "= mature mRNA (mostly)", "hnRNA / pre-mRNA → needs processing"],
        ["5' Cap", "ABSENT", "7-methylguanosine (m7G)"],
        ["3' Poly-A tail", "ABSENT", "40-250 adenylates (AAUAAA signal)"],
        ["Introns / Splicing", "Absent (most prokaryotes)", "Present; removed by spliceosome"],
        ["mRNA stability", "Short-lived (mins)", "Enhanced by cap + poly-A tail"],
        ["Termination", "Rho-independent or rho-dependent", "Linked to poly-A signal cleavage"],
        ["Antibiotic/toxin", "Rifampin (β subunit)", "α-Amanitin (RNA Pol II)"],
        ["rRNA source", "Pre-rRNA → 23S, 16S, 5S", "45S pre-rRNA → 28S, 18S, 5.8S"],
    ]

    cw_feat = 4.5*cm
    cw_pro  = (usable_w - cw_feat) / 2
    cw_euk  = (usable_w - cw_feat) / 2

    comp_table_data = [
        [Paragraph(comp_headers[0], S_TABLE_H),
         Paragraph(comp_headers[1], S_TABLE_H),
         Paragraph(comp_headers[2], S_TABLE_H)]
    ]
    for row in comp_rows:
        comp_table_data.append([
            Paragraph(row[0], make_style("CTF", fontName="Helvetica-Bold", fontSize=7.5, textColor=NAVY)),
            Paragraph(row[1], S_TABLE_B),
            Paragraph(row[2], S_TABLE_B),
        ])

    ctable = Table(comp_table_data, colWidths=[cw_feat, cw_pro, cw_euk])
    row_bg = []
    for i in range(1, len(comp_table_data)):
        bg = CYAN_LIGHT if i % 2 == 0 else WHITE
        row_bg.append(("BACKGROUND", (1, i), (1, i), bg))
        row_bg.append(("BACKGROUND", (2, i), (2, i), PURPLE_LIGHT if i % 2 == 0 else WHITE))
        row_bg.append(("BACKGROUND", (0, i), (0, i), GREY_LIGHT))

    ctable.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), NAVY),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 4), ("BOTTOMPADDING", (0, 0), (-1, -1), 4),
        ("LEFTPADDING", (0, 0), (-1, -1), 5),
        ("GRID", (0, 0), (-1, -1), 0.3, GREY_MID),
    ] + row_bg))
    story.append(ctable)
    story.append(Spacer(1, 5*mm))

    # Quick memory tips
    story.append(SectionHeader("  Memory Tips", bg=ORANGE_MID))
    story.append(Spacer(1, 3*mm))

    tips = [
        ("Pribnow = -10 box", "Remember: P comes before T in the alphabet; Pribnow (-10) is closer to the start site than the -35 sequence."),
        ("σ70 = 70 kDa sigma", "The most common sigma factor in E. coli. 'σ70 in bacteria, TFIID in eukaryotes' — both are the first to recognize the core promoter."),
        ("AAUAAA = poly-A signal", "A mnemonic: 'AA U AAA' — the signal that says 'Add Adenines Until AAA.'"),
        ("GU-AG rule", "Introns begin with GU (5' splice site donor) and end with AG (3' splice site acceptor). 'GU...AG' = the spliceosome's address."),
        ("No cap in bacteria", "Prokaryotic mRNAs have no 5' cap and no poly-A tail — their mRNA is directly translated. Only eukaryotes need these modifications."),
    ]
    tips_data = [[Paragraph(f"<b>{t}</b>", S_H3), Paragraph(d, S_BODY)] for t, d in tips]
    tips_table = Table(tips_data, colWidths=[5*cm, usable_w - 5*cm])
    tips_table.setStyle(TableStyle([
        ("ROWBACKGROUNDS", (0, 0), (-1, -1), [ORANGE_LIGHT, WHITE]),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("TOPPADDING", (0, 0), (-1, -1), 5), ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
        ("GRID", (0, 0), (-1, -1), 0.3, GREY_MID),
    ]))
    story.append(tips_table)
    story.append(Spacer(1, 4*mm))

    # Footer note
    story.append(Paragraph(
        "Sources: Lippincott's Illustrated Reviews in Biochemistry 8e | Basic Medical Biochemistry: A Clinical Approach 6e | "
        "Thompson & Thompson Genetics and Genomics in Medicine 9e | Medical Microbiology 9e",
        S_CAPTION))

    # ── Build ─────────────────────────────────────────────────────────────
    doc.build(story)
    print(f"PDF saved to: {path}")


if __name__ == "__main__":
    out = "/tmp/workspace/transcription-guide/Transcription_Visual_Study_Guide.pdf"
    build_pdf(out)

Successfully replaced 1 instance(s) of the string in '/tmp/workspace/transcription-guide/generate_guide.py'

Successfully replaced 1 instance(s) of the string in '/tmp/workspace/transcription-guide/generate_guide.py'