mkdir -p /home/daytona/workspace/cell-notes && ls /home/daytona/workspace/cell-n…

~/cell-notes/generate_notes.py

#!/usr/bin/env python3
"""
Class 11 Botany - The Unit of Life (Cell Chapter)
Topper-quality handwritten-style notes with diagrams
"""

from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.units import cm, mm
from reportlab.pdfgen import canvas
from reportlab.lib.colors import HexColor, Color
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
import math

W, H = A4  # 595 x 842

# ── Colour palette (pastel / highlighter feel) ───────────────────────────────
BG        = HexColor("#FFFDF4")   # warm paper
TITLE_BG  = HexColor("#1A3C5E")   # deep navy for header bar
TITLE_FG  = colors.white
H1_COL    = HexColor("#1A3C5E")   # section heading
H2_COL    = HexColor("#C0392B")   # sub-heading
BODY_COL  = HexColor("#2C2C2C")
NOTE_COL  = HexColor("#8B4513")   # brown for margin notes
BOX_BLUE  = HexColor("#D6EAF8")
BOX_YEL   = HexColor("#FEF9E7")
BOX_GRN   = HexColor("#E9F7EF")
BOX_RED   = HexColor("#FDEDEC")
BORDER_BL = HexColor("#2980B9")
BORDER_GR = HexColor("#27AE60")
BORDER_RD = HexColor("#E74C3C")
BORDER_YL = HexColor("#F39C12")
ARROW_COL = HexColor("#7F8C8D")
DIAG_COL  = HexColor("#154360")   # dark blue for diagram outlines
HIGH_YEL  = HexColor("#FFFF99")   # yellow highlight
HIGH_GRN  = HexColor("#CCFFCC")

# ── Helpers ──────────────────────────────────────────────────────────────────

def new_page(c):
    c.showPage()
    draw_page_bg(c)
    draw_ruled_lines(c)

def draw_page_bg(c):
    c.setFillColor(BG)
    c.rect(0, 0, W, H, fill=1, stroke=0)

def draw_ruled_lines(c):
    c.setStrokeColor(HexColor("#E8E0D0"))
    c.setLineWidth(0.3)
    y = H - 2.5*cm
    while y > 1.5*cm:
        c.line(1.5*cm, y, W - 1.5*cm, y)
        y -= 0.7*cm
    # left margin line
    c.setStrokeColor(HexColor("#F5B7B1"))
    c.setLineWidth(0.8)
    c.line(2.8*cm, H - 2.5*cm, 2.8*cm, 1.5*cm)

def draw_header_bar(c, title, subtitle=""):
    c.setFillColor(TITLE_BG)
    c.rect(0, H - 2.0*cm, W, 2.0*cm, fill=1, stroke=0)
    c.setFillColor(TITLE_FG)
    c.setFont("Helvetica-Bold", 13)
    c.drawCentredString(W/2, H - 1.3*cm, title)
    if subtitle:
        c.setFont("Helvetica", 9)
        c.drawCentredString(W/2, H - 1.75*cm, subtitle)

def draw_footer(c, page_num):
    c.setFillColor(HexColor("#AAB7B8"))
    c.setFont("Helvetica", 8)
    c.drawCentredString(W/2, 0.7*cm, f"Class 11 Botany | The Unit of Life  •  Page {page_num}")
    # decorative line
    c.setStrokeColor(HexColor("#AAB7B8"))
    c.setLineWidth(0.5)
    c.line(1.5*cm, 1.1*cm, W - 1.5*cm, 1.1*cm)

def section_heading(c, text, y, col=H1_COL):
    """Bold section heading with underline."""
    c.setFillColor(col)
    c.setFont("Helvetica-Bold", 13)
    c.drawString(3.0*cm, y, text)
    c.setStrokeColor(col)
    c.setLineWidth(1.2)
    tw = c.stringWidth(text, "Helvetica-Bold", 13)
    c.line(3.0*cm, y - 2, 3.0*cm + tw, y - 2)
    return y - 0.7*cm

def sub_heading(c, text, y, col=H2_COL):
    c.setFillColor(col)
    c.setFont("Helvetica-Bold", 11)
    c.drawString(3.2*cm, y, text)
    return y - 0.55*cm

def body_text(c, text, y, indent=3.2*cm, font_size=9.5, col=BODY_COL, bold=False):
    font = "Helvetica-Bold" if bold else "Helvetica"
    c.setFillColor(col)
    c.setFont(font, font_size)
    c.drawString(indent, y, text)
    return y - 0.52*cm

def bullet(c, text, y, indent=3.5*cm, col=BODY_COL, bullet_col=H2_COL):
    c.setFillColor(bullet_col)
    c.circle(indent - 0.25*cm, y + 0.12*cm, 0.08*cm, fill=1, stroke=0)
    c.setFillColor(col)
    c.setFont("Helvetica", 9.5)
    # wrap long text
    max_w = W - indent - 1.5*cm
    words = text.split()
    line = ""
    lines = []
    for w in words:
        test = line + " " + w if line else w
        if c.stringWidth(test, "Helvetica", 9.5) < max_w:
            line = test
        else:
            lines.append(line)
            line = w
    lines.append(line)
    for i, ln in enumerate(lines):
        c.drawString(indent + (0 if i == 0 else 0.2*cm), y - i*0.48*cm, ln)
    return y - len(lines)*0.48*cm - 0.1*cm

def highlight_box(c, x, y, w, h, bg=BOX_YEL, border=BORDER_YL, title="", lines=[], font_size=9):
    c.setFillColor(bg)
    c.setStrokeColor(border)
    c.setLineWidth(1.2)
    c.roundRect(x, y, w, h, 4, fill=1, stroke=1)
    ty = y + h - 0.4*cm
    if title:
        c.setFillColor(border)
        c.setFont("Helvetica-Bold", 9.5)
        c.drawString(x + 0.2*cm, ty, title)
        ty -= 0.45*cm
    c.setFillColor(BODY_COL)
    c.setFont("Helvetica", font_size)
    for ln in lines:
        c.drawString(x + 0.2*cm, ty, ln)
        ty -= 0.44*cm

def margin_note(c, text, y):
    c.setFillColor(NOTE_COL)
    c.setFont("Helvetica-Oblique", 8)
    c.drawString(0.25*cm, y, text)

def star_icon(c, x, y, col=HexColor("#E74C3C")):
    """Draw a small star."""
    c.setFillColor(col)
    c.setFont("Helvetica-Bold", 12)
    c.drawString(x, y, "★")

def draw_arrow(c, x1, y1, x2, y2, col=ARROW_COL):
    c.setStrokeColor(col)
    c.setLineWidth(0.8)
    c.line(x1, y1, x2, y2)
    # arrowhead
    angle = math.atan2(y2 - y1, x2 - x1)
    size = 0.2*cm
    for da in [0.4, -0.4]:
        ax = x2 - size * math.cos(angle - da)
        ay = y2 - size * math.sin(angle - da)
        c.line(x2, y2, ax, ay)

# ════════════════════════════════════════════════════════════════════════════
#  DIAGRAM FUNCTIONS
# ════════════════════════════════════════════════════════════════════════════

def draw_cell_diagram_animal(c, cx, cy, r=2.8*cm):
    """Draw a labelled animal cell."""
    # outer boundary (cell membrane)
    c.setStrokeColor(HexColor("#154360"))
    c.setFillColor(HexColor("#EBF5FB"))
    c.setLineWidth(1.5)
    c.ellipse(cx - r, cy - r*0.75, cx + r, cy + r*0.75, fill=1, stroke=1)

    # Nucleus
    nr = r * 0.35
    c.setFillColor(HexColor("#D4E6F1"))
    c.setStrokeColor(HexColor("#1A3C5E"))
    c.setLineWidth(1.2)
    c.ellipse(cx - nr, cy - nr*0.8, cx + nr, cy + nr*0.8, fill=1, stroke=1)
    # nucleolus
    c.setFillColor(HexColor("#1A3C5E"))
    c.circle(cx + 0.1*cm, cy + 0.05*cm, 0.12*cm, fill=1, stroke=0)

    # Mitochondria (2 small ellipses)
    for mx, my in [(cx + 1.5*cm, cy - 0.8*cm), (cx - 1.8*cm, cy + 0.5*cm)]:
        c.setFillColor(HexColor("#FDEBD0"))
        c.setStrokeColor(HexColor("#E67E22"))
        c.setLineWidth(0.8)
        c.ellipse(mx - 0.3*cm, my - 0.15*cm, mx + 0.3*cm, my + 0.15*cm, fill=1, stroke=1)
        # cristae lines
        c.setStrokeColor(HexColor("#E67E22"))
        c.setLineWidth(0.5)
        c.line(mx - 0.1*cm, my - 0.13*cm, mx - 0.1*cm, my + 0.13*cm)
        c.line(mx + 0.1*cm, my - 0.13*cm, mx + 0.1*cm, my + 0.13*cm)

    # Endoplasmic reticulum (wavy lines)
    c.setStrokeColor(HexColor("#8E44AD"))
    c.setLineWidth(0.6)
    for i in range(3):
        yy = cy - 0.4*cm + i*0.3*cm
        p = c.beginPath()
        p.moveTo(cx + 0.6*cm, yy)
        for j in range(4):
            xj = cx + 0.6*cm + j*0.35*cm
            dy = 0.1*cm if j % 2 == 0 else -0.1*cm
            p.lineTo(xj + 0.35*cm, yy + dy)
        c.drawPath(p, stroke=1, fill=0)

    # Golgi (stack of arcs)
    gx, gy = cx - 0.7*cm, cy - 1.2*cm
    c.setStrokeColor(HexColor("#1E8449"))
    c.setLineWidth(0.8)
    for i in range(3):
        arc_r = 0.3*cm + i*0.08*cm
        c.arc(gx - arc_r, gy - 0.1*cm, gx + arc_r, gy + 0.1*cm, 0, 180)
        gy += 0.18*cm

    # Ribosome dots
    c.setFillColor(HexColor("#E74C3C"))
    for rx, ry in [(cx + 0.4*cm, cy + 0.9*cm), (cx + 0.6*cm, cy + 0.75*cm),
                   (cx - 1.0*cm, cy - 0.9*cm), (cx + 1.8*cm, cy + 0.4*cm)]:
        c.circle(rx, ry, 0.06*cm, fill=1, stroke=0)

    # Vacuole (small)
    c.setFillColor(HexColor("#D6EAF8"))
    c.setStrokeColor(HexColor("#2980B9"))
    c.setLineWidth(0.6)
    c.ellipse(cx - 1.9*cm, cy - 0.3*cm, cx - 1.2*cm, cy + 0.2*cm, fill=1, stroke=1)

    # Labels with arrows
    label_map = [
        (cx + r + 0.15*cm,    cy + 0.55*cm,   cx + r - 0.05*cm, cy + 0.2*cm,   "Cell Membrane"),
        (cx + nr + 0.15*cm,   cy + nr + 0.2*cm, cx + 0.1*cm,    cy + nr*0.5,   "Nucleus"),
        (cx + 0.05*cm,        cy + 0.05*cm,   cx + 0.05*cm,     cy + 0.05*cm,  "Nucleolus"),
        (cx + 2.1*cm,         cy - 1.3*cm,    cx + 1.8*cm,      cy - 0.85*cm,  "Mitochondria"),
        (cx + 2.1*cm,         cy + 0.55*cm,   cx + 1.5*cm,      cy + 0.3*cm,   "ER (Rough)"),
        (cx - 2.6*cm,         cy - 1.5*cm,    cx - 0.7*cm,      cy - 1.2*cm,   "Golgi Body"),
        (cx + 0.1*cm,         cy + 1.3*cm,    cx + 0.5*cm,      cy + 0.95*cm,  "Ribosomes"),
        (cx - 2.6*cm,         cy - 0.05*cm,   cx - 1.9*cm,      cy - 0.05*cm,  "Vacuole"),
    ]
    c.setFont("Helvetica", 7.5)
    for lx, ly, ax, ay, lbl in label_map:
        c.setFillColor(HexColor("#154360"))
        c.drawString(lx, ly, lbl)
        draw_arrow(c, ax, ay, lx - 0.05*cm, ly + 0.05*cm, col=HexColor("#5D6D7E"))

def draw_plant_cell(c, cx, cy, r=3.0*cm):
    """Draw a labelled plant cell."""
    # Cell wall (outer rect-ish)
    c.setFillColor(HexColor("#EAFAF1"))
    c.setStrokeColor(HexColor("#196F3D"))
    c.setLineWidth(2.5)
    c.roundRect(cx - r, cy - r*0.85, 2*r, 2*r*0.85, 5, fill=1, stroke=1)
    # Cell membrane (inner)
    c.setFillColor(colors.transparent)
    c.setStrokeColor(HexColor("#154360"))
    c.setLineWidth(0.8)
    pad = 0.15*cm
    c.roundRect(cx - r + pad, cy - r*0.85 + pad, 2*r - 2*pad, 2*r*0.85 - 2*pad, 3, fill=0, stroke=1)

    # Large central vacuole
    vr = r * 0.5
    c.setFillColor(HexColor("#D6EAF8"))
    c.setStrokeColor(HexColor("#2980B9"))
    c.setLineWidth(0.8)
    c.ellipse(cx - vr, cy - vr*0.7, cx + vr, cy + vr*0.7, fill=1, stroke=1)

    # Nucleus (peripheral)
    nr = r * 0.3
    nx, ny = cx - 1.5*cm, cy + 1.5*cm
    # clamp inside cell
    if ny + nr > cy + r*0.85 - pad: ny = cy + r*0.85 - pad - nr
    c.setFillColor(HexColor("#D4E6F1"))
    c.setStrokeColor(HexColor("#1A3C5E"))
    c.setLineWidth(1.0)
    c.ellipse(nx - nr, ny - nr*0.8, nx + nr, ny + nr*0.8, fill=1, stroke=1)
    c.setFillColor(HexColor("#1A3C5E"))
    c.circle(nx + 0.05*cm, ny, 0.1*cm, fill=1, stroke=0)

    # Chloroplasts (2, oval green with grana)
    for clx, cly in [(cx + 1.2*cm, cy + 1.4*cm), (cx - 0.2*cm, cy - 1.5*cm)]:
        c.setFillColor(HexColor("#A9DFBF"))
        c.setStrokeColor(HexColor("#196F3D"))
        c.setLineWidth(0.7)
        c.ellipse(clx - 0.45*cm, cly - 0.2*cm, clx + 0.45*cm, cly + 0.2*cm, fill=1, stroke=1)
        # grana stacks
        c.setFillColor(HexColor("#1E8449"))
        for gi in [-1, 0, 1]:
            c.rect(clx + gi*0.12*cm - 0.04*cm, cly - 0.1*cm, 0.08*cm, 0.2*cm, fill=1, stroke=0)

    # Mitochondria
    c.setFillColor(HexColor("#FDEBD0"))
    c.setStrokeColor(HexColor("#E67E22"))
    c.setLineWidth(0.7)
    c.ellipse(cx + 1.8*cm, cy - 0.3*cm, cx + 2.4*cm, cy - 0.0*cm, fill=1, stroke=1)

    # Labels
    label_map = [
        (cx + r + 0.1*cm,  cy + 1.5*cm,  cx + r - 0.05*cm, cy + 1.0*cm, "Cell Wall"),
        (cx + r + 0.1*cm,  cy + 0.9*cm,  cx + r - 0.15*cm, cy + 0.5*cm, "Cell Membrane"),
        (cx + r + 0.1*cm,  cy - 0.0*cm,  cx + vr + 0.1*cm, cy,          "Central Vacuole"),
        (cx + r + 0.1*cm,  cy - 0.8*cm,  cx + r - 0.15*cm, cy - 0.55*cm,"Mitochondria"),
        (cx + r + 0.1*cm,  cy - 1.5*cm,  cx + 1.5*cm,      cy + 1.4*cm, "Chloroplast"),
        (cx - r - 2.2*cm,  cy + 1.5*cm,  cx - 1.5*cm,      cy + 1.5*cm, "Nucleus"),
        (cx - r - 2.2*cm,  cy + 0.8*cm,  cx - 1.5*cm,      cy + 1.0*cm, "Nucleolus"),
        (cx - r - 2.2*cm,  cy - 1.5*cm,  cx - 0.2*cm,      cy - 1.5*cm, "Chloroplast"),
    ]
    c.setFont("Helvetica", 7.5)
    for lx, ly, ax, ay, lbl in label_map:
        c.setFillColor(HexColor("#154360"))
        c.drawString(lx, ly, lbl)
        draw_arrow(c, ax, ay, lx - 0.05*cm, ly + 0.05*cm, col=HexColor("#5D6D7E"))

def draw_cell_membrane_model(c, cx, cy):
    """Fluid mosaic model of cell membrane."""
    bw, bh = 9*cm, 1.8*cm
    x0 = cx - bw/2
    # Phospholipid bilayer
    head_r = 0.18*cm
    tail_l = 0.4*cm
    step = 0.4*cm
    # Top layer heads
    c.setFillColor(HexColor("#F1948A"))
    c.setStrokeColor(HexColor("#C0392B"))
    c.setLineWidth(0.5)
    for i in range(int(bw/step)):
        hx = x0 + i*step + step/2
        # head
        c.circle(hx, cy + tail_l + head_r, head_r, fill=1, stroke=1)
        # tails
        c.setStrokeColor(HexColor("#7F8C8D"))
        c.setLineWidth(0.6)
        c.line(hx - 0.05*cm, cy + tail_l, hx - 0.05*cm, cy)
        c.line(hx + 0.05*cm, cy + tail_l, hx + 0.05*cm, cy + 0.05*cm)
        c.setStrokeColor(HexColor("#C0392B"))
        c.setFillColor(HexColor("#F1948A"))
        c.setLineWidth(0.5)

    # Bottom layer heads (inverted)
    for i in range(int(bw/step)):
        hx = x0 + i*step + step/2
        c.circle(hx, cy - tail_l - head_r, head_r, fill=1, stroke=1)
        c.setStrokeColor(HexColor("#7F8C8D"))
        c.setLineWidth(0.6)
        c.line(hx - 0.05*cm, cy - tail_l, hx - 0.05*cm, cy)
        c.line(hx + 0.05*cm, cy - tail_l, hx + 0.05*cm, cy - 0.05*cm)
        c.setStrokeColor(HexColor("#C0392B"))
        c.setFillColor(HexColor("#F1948A"))
        c.setLineWidth(0.5)

    # Integral proteins (2 large oval spanning bilayer)
    for px in [x0 + 2.0*cm, x0 + 6.5*cm]:
        c.setFillColor(HexColor("#A9CCE3"))
        c.setStrokeColor(HexColor("#1A5276"))
        c.setLineWidth(0.8)
        c.ellipse(px - 0.35*cm, cy - tail_l - head_r*0.5, px + 0.35*cm, cy + tail_l + head_r*0.5, fill=1, stroke=1)

    # Peripheral protein
    c.setFillColor(HexColor("#F9E79F"))
    c.setStrokeColor(HexColor("#9A7D0A"))
    c.setLineWidth(0.7)
    c.ellipse(x0 + 4.0*cm, cy + tail_l - 0.1*cm, x0 + 4.7*cm, cy + tail_l + head_r*1.5, fill=1, stroke=1)

    # Cholesterol (wedge shape)
    c.setFillColor(HexColor("#D7BDE2"))
    c.setStrokeColor(HexColor("#6C3483"))
    c.setLineWidth(0.6)
    c.ellipse(x0 + 7.5*cm, cy - 0.1*cm, x0 + 7.9*cm, cy + 0.35*cm, fill=1, stroke=1)

    # Labels
    c.setFont("Helvetica", 7.5)
    lbl_data = [
        (x0 - 0.1*cm,      cy + tail_l + head_r + 0.1*cm,  "Phospholipid Head (Hydrophilic)"),
        (x0 - 0.1*cm,      cy - tail_l - head_r - 0.25*cm, "Phospholipid Head"),
        (x0 + 0.8*cm,      cy + 0.5*cm,                    "Hydrophobic tails"),
        (x0 + 1.0*cm,      cy - 1.0*cm,                    "Integral Protein"),
        (x0 + 3.5*cm,      cy + 1.1*cm,                    "Peripheral Protein"),
        (x0 + 7.1*cm,      cy - 0.9*cm,                    "Cholesterol"),
    ]
    for lx, ly, lbl in lbl_data:
        c.setFillColor(HexColor("#154360"))
        c.drawString(lx, ly, lbl)

def draw_mitosis_phases(c, x0, y0):
    """Simple mitosis phase sequence."""
    phases = ["Prophase", "Metaphase", "Anaphase", "Telophase"]
    colors_p = [HexColor("#D4E6F1"), HexColor("#D5F5E3"), HexColor("#FCF3CF"), HexColor("#FDEBD0")]
    bw, bh = 2.5*cm, 2.5*cm
    gap = 0.4*cm
    for i, (ph, col) in enumerate(zip(phases, colors_p)):
        bx = x0 + i*(bw + gap)
        by = y0
        c.setFillColor(col)
        c.setStrokeColor(HexColor("#2C3E50"))
        c.setLineWidth(0.8)
        c.roundRect(bx, by, bw, bh, 4, fill=1, stroke=1)
        c.setFillColor(HexColor("#2C3E50"))
        c.setFont("Helvetica-Bold", 8)
        c.drawCentredString(bx + bw/2, by + bh - 0.45*cm, ph)
        # Draw simplified chromosome arrangement
        draw_phase_chromosomes(c, bx + bw/2, by + bh/2 - 0.3*cm, i)
        # arrow between phases
        if i < len(phases) - 1:
            ax = bx + bw + 0.05*cm
            ay = by + bh/2
            draw_arrow(c, ax, ay, ax + gap - 0.05*cm, ay, col=HexColor("#E74C3C"))

def draw_phase_chromosomes(c, cx, cy, phase):
    """Simplified chromosome drawings for each mitosis phase."""
    c.setFillColor(HexColor("#E74C3C"))
    c.setStrokeColor(HexColor("#922B21"))
    c.setLineWidth(0.8)
    if phase == 0:  # Prophase: X-shaped chromosomes scattered
        for dx, dy in [(-0.4, 0.3), (0.2, -0.2), (-0.1, -0.4)]:
            px, py = cx + dx*cm, cy + dy*cm
            c.setLineWidth(2.5)
            c.setStrokeColor(HexColor("#E74C3C"))
            c.line(px - 0.15*cm, py + 0.2*cm, px + 0.15*cm, py - 0.2*cm)
            c.line(px - 0.15*cm, py - 0.2*cm, px + 0.15*cm, py + 0.2*cm)
    elif phase == 1:  # Metaphase: lined up at centre
        for dy in [-0.3, 0.0, 0.3]:
            py = cy + dy*cm
            c.setLineWidth(2.5)
            c.setStrokeColor(HexColor("#E74C3C"))
            c.line(cx - 0.12*cm, py + 0.18*cm, cx + 0.12*cm, py - 0.18*cm)
            c.line(cx - 0.12*cm, py - 0.18*cm, cx + 0.12*cm, py + 0.18*cm)
        # metaphase plate
        c.setStrokeColor(HexColor("#196F3D"))
        c.setLineWidth(0.7)
        c.setDash(2, 2)
        c.line(cx, cy - 0.5*cm, cx, cy + 0.5*cm)
        c.setDash()
    elif phase == 2:  # Anaphase: moving to poles
        for side in [-1, 1]:
            for dy in [-0.15, 0.15]:
                px, py = cx + side*0.45*cm, cy + dy*cm
                c.setLineWidth(2.0)
                c.setStrokeColor(HexColor("#E74C3C"))
                c.line(px - 0.08*cm, py + 0.12*cm, px + 0.08*cm, py - 0.12*cm)
    elif phase == 3:  # Telophase: 2 nuclei forming
        for nx in [-0.38, 0.38]:
            c.setFillColor(HexColor("#D4E6F1"))
            c.setStrokeColor(HexColor("#1A3C5E"))
            c.setLineWidth(0.7)
            c.circle(cx + nx*cm, cy, 0.3*cm, fill=1, stroke=1)
        # cleavage furrow
        c.setStrokeColor(HexColor("#196F3D"))
        c.setLineWidth(0.8)
        c.setDash(3, 2)
        c.line(cx, cy - 0.4*cm, cx, cy + 0.4*cm)
        c.setDash()

def draw_nucleus_diagram(c, cx, cy):
    """Labelled nucleus diagram."""
    r = 1.8*cm
    # Nuclear envelope
    c.setFillColor(HexColor("#D4E6F1"))
    c.setStrokeColor(HexColor("#1A3C5E"))
    c.setLineWidth(1.5)
    c.ellipse(cx - r, cy - r*0.75, cx + r, cy + r*0.75, fill=1, stroke=1)
    # Inner membrane line
    c.setStrokeColor(HexColor("#5DADE2"))
    c.setLineWidth(0.7)
    pad = 0.12*cm
    c.ellipse(cx - r + pad, cy - r*0.75 + pad, cx + r - pad, cy + r*0.75 - pad, fill=0, stroke=1)
    # Nuclear pores (small gaps)
    c.setFillColor(HexColor("#FDFEFE"))
    c.setStrokeColor(HexColor("#1A3C5E"))
    c.setLineWidth(0.5)
    pore_positions = [0, 45, 90, 135, 180, 225, 270, 315]
    for angle_deg in pore_positions:
        angle = math.radians(angle_deg)
        px = cx + (r - 0.02*cm) * math.cos(angle)
        py = cy + (r*0.75 - 0.02*cm) * math.sin(angle)
        c.circle(px, py, 0.08*cm, fill=1, stroke=1)
    # Nucleolus
    c.setFillColor(HexColor("#1A3C5E"))
    c.circle(cx - 0.3*cm, cy + 0.2*cm, 0.25*cm, fill=1, stroke=0)
    # Chromatin threads
    c.setStrokeColor(HexColor("#8E44AD"))
    c.setLineWidth(0.5)
    for i in range(4):
        sx = cx - 1.0*cm + i*0.5*cm
        sy = cy - 0.3*cm
        p = c.beginPath()
        p.moveTo(sx, sy)
        p.curveTo(sx + 0.2*cm, sy + 0.4*cm, sx + 0.4*cm, sy - 0.3*cm, sx + 0.6*cm, sy + 0.2*cm)
        c.drawPath(p, stroke=1, fill=0)
    # Labels
    label_data = [
        (cx + r + 0.15*cm, cy + 0.6*cm,  "Nuclear Envelope"),
        (cx + r + 0.15*cm, cy + 0.0*cm,  "Nuclear Pore"),
        (cx - r - 2.5*cm,  cy + 0.3*cm,  "Nucleolus"),
        (cx - r - 2.5*cm,  cy - 0.4*cm,  "Chromatin"),
        (cx + r + 0.15*cm, cy - 0.6*cm,  "Inner Membrane"),
    ]
    c.setFont("Helvetica", 8)
    for lx, ly, lbl in label_data:
        c.setFillColor(HexColor("#154360"))
        c.drawString(lx, ly, lbl)
        if lx > cx:
            draw_arrow(c, cx + r*0.8, cy, lx - 0.1*cm, ly + 0.06*cm)
        else:
            draw_arrow(c, cx - r*0.7, cy, lx + c.stringWidth(lbl, "Helvetica", 8) + 0.15*cm, ly + 0.06*cm)

def draw_comparison_table(c, x, y, w, rows, header_bg=HexColor("#1A3C5E"),
                           row_colors=[BOX_YEL, BOX_GRN], col_widths=None):
    """Generic comparison table."""
    header, *data = rows
    ncols = len(header)
    if not col_widths:
        col_widths = [w / ncols] * ncols
    row_h = 0.5*cm
    # Header
    c.setFillColor(header_bg)
    c.rect(x, y - row_h, w, row_h, fill=1, stroke=0)
    c.setFillColor(colors.white)
    c.setFont("Helvetica-Bold", 9)
    cx_ = x
    for i, cell in enumerate(header):
        c.drawCentredString(cx_ + col_widths[i]/2, y - row_h + 0.12*cm, cell)
        cx_ += col_widths[i]
    y -= row_h
    # Rows
    for ri, row in enumerate(data):
        bg = row_colors[ri % 2]
        c.setFillColor(bg)
        c.rect(x, y - row_h, w, row_h, fill=1, stroke=0)
        # grid lines
        c.setStrokeColor(HexColor("#BDC3C7"))
        c.setLineWidth(0.4)
        c.rect(x, y - row_h, w, row_h, fill=0, stroke=1)
        c.setFillColor(BODY_COL)
        c.setFont("Helvetica", 8.5)
        cx_ = x
        for i, cell in enumerate(row):
            c.drawString(cx_ + 0.15*cm, y - row_h + 0.13*cm, str(cell))
            cx_ += col_widths[i]
        y -= row_h
    return y


# ════════════════════════════════════════════════════════════════════════════
#  BUILD PDF
# ════════════════════════════════════════════════════════════════════════════

def build_pdf(path):
    c = canvas.Canvas(path, pagesize=A4)
    c.setTitle("Class 11 Botany - The Unit of Life (Cell Chapter)")

    # ── PAGE 1: Title & Cell Theory ──────────────────────────────────────────
    draw_page_bg(c)
    draw_ruled_lines(c)

    # Big title banner
    c.setFillColor(TITLE_BG)
    c.rect(0, H - 3.5*cm, W, 3.5*cm, fill=1, stroke=0)
    c.setFillColor(TITLE_FG)
    c.setFont("Helvetica-Bold", 20)
    c.drawCentredString(W/2, H - 1.8*cm, "THE UNIT OF LIFE")
    c.setFont("Helvetica-Bold", 13)
    c.setFillColor(HexColor("#AED6F1"))
    c.drawCentredString(W/2, H - 2.5*cm, "Class 11 Biology | Chapter 8  ★ Topper Notes ★")
    c.setFont("Helvetica", 9)
    c.setFillColor(HexColor("#D6EAF8"))
    c.drawCentredString(W/2, H - 3.1*cm, "Cell Theory • Cell Types • Organelles • Cell Division • Cell Membrane Model")

    y = H - 4.0*cm

    # Cell Theory box
    highlight_box(c, 3.0*cm, y - 3.2*cm, W - 5.0*cm, 3.0*cm,
                  bg=BOX_BLUE, border=BORDER_BL,
                  title="📌 CELL THEORY (Must Know!)",
                  lines=[
                      "1. All living organisms are composed of cells.  [Schleiden & Schwann, 1838-39]",
                      "2. Cell is the basic structural & functional unit of life.",
                      "3. All cells arise from pre-existing cells.  [Rudolf Virchow, 1855]",
                      "★ Exception: Viruses are NOT made of cells (acellular).",
                  ])
    y -= 3.4*cm

    y = section_heading(c, "🔬  TYPES OF CELLS", y)

    # Prokaryotic vs Eukaryotic comparison table
    rows = [
        ["Feature", "Prokaryotic Cell", "Eukaryotic Cell"],
        ["Size", "1-10 µm (smaller)", "10-100 µm (larger)"],
        ["Nucleus", "No true nucleus", "True nucleus (membrane-bound)"],
        ["Membrane-bound organelles", "Absent", "Present (mitochondria, ER, etc.)"],
        ["DNA", "Naked, circular, no histone", "Linear, histone-bound"],
        ["Ribosomes", "70S (50S + 30S)", "80S (60S + 40S)"],
        ["Cell Wall", "Present (peptidoglycan)", "Plants: cellulose; Fungi: chitin"],
        ["Examples", "Bacteria, Cyanobacteria", "Amoeba, Plants, Fungi, Animals"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y - 0.2*cm, W - 5.0*cm, rows,
                              col_widths=[4.5*cm, 5.5*cm, 5.5*cm])

    margin_note(c, "Prokaryote", y + 1.5*cm)
    margin_note(c, "= 'before", y + 1.0*cm)
    margin_note(c, "  nucleus'", y + 0.5*cm)

    y -= 0.4*cm
    highlight_box(c, 3.0*cm, y - 1.6*cm, W - 5.0*cm, 1.4*cm,
                  bg=BOX_YEL, border=BORDER_YL,
                  title="🧠 MNEMONIC",
                  lines=["Prokaryote: 'Before Kernel' (no real nucleus)",
                         "Eukaryote: 'True Kernel' (proper nucleus with envelope)"])
    y -= 1.8*cm

    draw_footer(c, 1)

    # ── PAGE 2: Animal & Plant Cell Diagrams ────────────────────────────────
    new_page(c)
    draw_header_bar(c, "CELL STRUCTURE — Diagrams", "Animal Cell vs Plant Cell")

    y = H - 2.5*cm

    section_heading(c, "ANIMAL CELL DIAGRAM (Labelled)", y)
    y -= 0.4*cm
    # Animal cell diagram centred
    draw_cell_diagram_animal(c, W/2 - 3*cm, y - 3.5*cm)
    y -= 7.2*cm

    section_heading(c, "PLANT CELL DIAGRAM (Labelled)", y)
    y -= 0.4*cm
    draw_plant_cell(c, W/2 - 1*cm, y - 3.8*cm)
    y -= 7.5*cm

    highlight_box(c, 3.0*cm, y - 1.8*cm, W - 5.0*cm, 1.6*cm,
                  bg=BOX_GRN, border=BORDER_GR,
                  title="✅ Plant Cell EXTRA structures vs Animal Cell:",
                  lines=["★ Cell Wall (cellulose)  ★ Chloroplasts  ★ Large Central Vacuole  ★ Plasmodesmata",
                         "★ Glyoxysomes  |  Animal cell has: Centrioles, Lysosomes (absent in plant cells)"])

    draw_footer(c, 2)

    # ── PAGE 3: Cell Organelles Part 1 ──────────────────────────────────────
    new_page(c)
    draw_header_bar(c, "CELL ORGANELLES — Part 1", "Nucleus · ER · Golgi · Mitochondria")

    y = H - 2.5*cm

    # Nucleus
    y = section_heading(c, "1️⃣  NUCLEUS", y)
    # Draw nucleus diagram on right, notes on left
    draw_nucleus_diagram(c, W - 5.5*cm, y - 2.5*cm)

    y = sub_heading(c, "Structure:", y)
    y = bullet(c, "Bounded by double-layered nuclear envelope (inner + outer membrane)", y)
    y = bullet(c, "Nuclear pores: regulate entry/exit of molecules (mRNA, proteins)", y)
    y = bullet(c, "Nucleolus: site of rRNA synthesis and ribosome assembly", y)
    y = bullet(c, "Chromatin: DNA + histone proteins (condensed → chromosomes during division)", y)
    y = sub_heading(c, "Functions:", y - 0.1*cm)
    y = bullet(c, "Controls all cellular activities ('Control Centre' of cell)", y)
    y = bullet(c, "Hereditary material (DNA) is stored here", y)
    y = bullet(c, "Site of transcription (DNA → mRNA)", y)
    y -= 3.0*cm  # skip past diagram area

    # Endoplasmic Reticulum
    y = section_heading(c, "2️⃣  ENDOPLASMIC RETICULUM (ER)", y)
    highlight_box(c, 3.0*cm, y - 2.3*cm, W - 5.0*cm, 2.1*cm,
                  bg=BOX_YEL, border=BORDER_YL, title="",
                  lines=[
                      "Rough ER (RER):  Has ribosomes → Protein synthesis & secretion",
                      "Smooth ER (SER): No ribosomes → Lipid & steroid synthesis, detoxification",
                      "★ Forms the endomembrane system with Golgi and lysosomes",
                      "★ RER forms the outer nuclear envelope membrane",
                  ])
    y -= 2.5*cm

    # Golgi Apparatus
    y = section_heading(c, "3️⃣  GOLGI APPARATUS (Golgi Body)", y)
    y = bullet(c, "Stack of flattened membrane-bound cisternae (4-8 in number)", y)
    y = bullet(c, "Cis face (receiving face): receives vesicles from ER", y)
    y = bullet(c, "Trans face (shipping face): sends modified molecules outward", y)
    y = bullet(c, "Functions: modification, packaging, sorting & secretion of proteins/lipids", y)
    y = bullet(c, "Produces lysosomes, forms acrosome of sperm, produces cell wall in plant cells", y)

    margin_note(c, "★ Golgi:", y + 2.5*cm)
    margin_note(c, "'Post", y + 2.0*cm)
    margin_note(c, " Office'", y + 1.5*cm)
    margin_note(c, " of cell", y + 1.0*cm)

    y -= 0.3*cm
    # Mitochondria
    y = section_heading(c, "4️⃣  MITOCHONDRIA", y)
    highlight_box(c, 3.0*cm, y - 2.6*cm, W - 5.0*cm, 2.4*cm,
                  bg=BOX_GRN, border=BORDER_GR, title="",
                  lines=[
                      "Double membrane: outer (smooth) + inner (folded as CRISTAE)",
                      "Matrix: contains enzymes of Krebs cycle, own DNA (circular), 70S ribosomes",
                      "★ POWERHOUSE of the cell → ATP production by cellular respiration",
                      "★ Semi-autonomous: has own DNA & ribosomes → self-replicating",
                      "Cristae increase surface area for ATP synthesis (inner membrane)",
                  ])
    y -= 2.8*cm

    draw_footer(c, 3)

    # ── PAGE 4: Cell Organelles Part 2 ──────────────────────────────────────
    new_page(c)
    draw_header_bar(c, "CELL ORGANELLES — Part 2", "Plastids · Ribosomes · Lysosomes · Vacuoles · Centrosome")

    y = H - 2.5*cm

    # Plastids
    y = section_heading(c, "5️⃣  PLASTIDS (Plant cells only)", y)
    y = sub_heading(c, "Types of Plastids:", y)
    rows2 = [
        ["Type", "Colour", "Function"],
        ["Chloroplasts", "Green (chlorophyll)", "Photosynthesis"],
        ["Chromoplasts", "Yellow/Red/Orange (carotenoids)", "Impart colour to flowers/fruits"],
        ["Leucoplasts", "Colourless", "Storage (amyloplasts=starch, elaioplasts=oil)"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y, W - 5.0*cm, rows2,
                              col_widths=[4.0*cm, 5.5*cm, 5.5*cm])
    y -= 0.2*cm
    y = bullet(c, "Chloroplast: double membrane; thylakoids stacked → GRANA; stroma contains enzymes", y)
    y = bullet(c, "Thylakoid membrane: site of light reactions (photosystem I & II)", y)
    y = bullet(c, "Stroma: site of dark reactions (Calvin cycle, CO₂ fixation)", y)
    y = bullet(c, "Semi-autonomous: own 70S ribosomes, circular DNA → can self-replicate", y)

    highlight_box(c, 3.0*cm, y - 1.2*cm, W - 5.0*cm, 1.0*cm,
                  bg=BOX_RED, border=BORDER_RD, title="",
                  lines=["Interconvertibility: Leucoplasts ⇌ Chromoplasts ⇌ Chloroplasts"])
    y -= 1.5*cm

    # Ribosomes
    y = section_heading(c, "6️⃣  RIBOSOMES", y)
    y = bullet(c, "Smallest cell organelle; NO membrane", y)
    y = bullet(c, "Made of rRNA + proteins; two subunits (large & small)", y)
    y = bullet(c, "Prokaryotes: 70S = 50S + 30S   |   Eukaryotes: 80S = 60S + 40S", y, bold_label=True)
    y = bullet(c, "Polyribosomes (polysomes): cluster of ribosomes on single mRNA", y)
    y = bullet(c, "Function: Protein synthesis (translation)", y)
    y -= 0.2*cm

    # Lysosomes
    y = section_heading(c, "7️⃣  LYSOSOMES", y)
    y = bullet(c, "Membrane-bound vesicles with hydrolytic enzymes (acid hydrolases, ~40 types)", y)
    y = bullet(c, "'Suicide bags' of the cell (Christian de Duve, 1955)", y)
    y = bullet(c, "Functions: intracellular digestion, autophagy, autolysis", y)
    y = bullet(c, "pH ~5 (acidic) inside; absent in plant cells", y)
    y -= 0.2*cm

    # Vacuoles
    y = section_heading(c, "8️⃣  VACUOLES", y)
    y = bullet(c, "Membrane: Tonoplast  |  Content: Cell sap (water, salts, sugars, pigments)", y)
    y = bullet(c, "Plant cells: large central vacuole (up to 90% of cell volume)", y)
    y = bullet(c, "Animal cells: small, temporary food/contractile vacuoles", y)
    y = bullet(c, "Functions: storage, turgor pressure, waste disposal", y)
    y -= 0.2*cm

    # Centrosome
    y = section_heading(c, "9️⃣  CENTROSOME & CENTRIOLES", y)
    y = bullet(c, "Present in animal cells & lower plants (absent in higher plants)", y)
    y = bullet(c, "Centrioles: 9 triplet microtubules arranged in ring (9+0 pattern)", y)
    y = bullet(c, "Function: forms spindle fibres during cell division; forms basal body of cilia/flagella", y)

    draw_footer(c, 4)

    # ── PAGE 5: Cell Membrane + Fluid Mosaic Model ──────────────────────────
    new_page(c)
    draw_header_bar(c, "CELL MEMBRANE (Plasma Membrane)", "Fluid Mosaic Model · Transport")

    y = H - 2.7*cm

    y = section_heading(c, "STRUCTURE OF CELL MEMBRANE", y)
    y = bullet(c, "Phospholipid bilayer + proteins + cholesterol + carbohydrates", y)
    y = bullet(c, "Selectively permeable (semi-permeable): allows selective passage of substances", y)
    y -= 0.2*cm

    y = sub_heading(c, "Fluid Mosaic Model (Singer & Nicolson, 1972):", y)
    y = bullet(c, "FLUID: phospholipid molecules can move laterally (lateral diffusion)", y)
    y = bullet(c, "MOSAIC: proteins embedded in bilayer like tiles in a mosaic", y)
    y = bullet(c, "Integral (intrinsic) proteins: embedded within the lipid bilayer; form channels", y)
    y = bullet(c, "Peripheral (extrinsic) proteins: loosely attached on surface", y)
    y = bullet(c, "Cholesterol: maintains fluidity & rigidity of membrane", y)
    y = bullet(c, "Glycoproteins/Glycolipids: cell recognition, signalling, blood groups", y)
    y -= 0.3*cm

    # Fluid mosaic model diagram
    y = sub_heading(c, "Diagram — Fluid Mosaic Model:", y)
    draw_cell_membrane_model(c, W/2, y - 1.5*cm)
    y -= 3.5*cm

    # Transport
    y = section_heading(c, "MEMBRANE TRANSPORT", y)
    rows3 = [
        ["Transport Type", "Direction", "Energy", "Example"],
        ["Simple Diffusion", "High → Low conc.", "None (passive)", "O₂, CO₂, ethanol"],
        ["Facilitated Diffusion", "High → Low conc.", "None (passive)", "Glucose via GLUT"],
        ["Osmosis", "High water → Low water", "None (passive)", "Water via aquaporins"],
        ["Active Transport", "Low → High conc.", "ATP required", "Na⁺/K⁺ pump"],
        ["Endocytosis", "Outside → inside", "ATP required", "Phagocytosis, pinocytosis"],
        ["Exocytosis", "Inside → outside", "ATP required", "Secretion of enzymes"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y - 0.2*cm, W - 5.0*cm, rows3,
                              col_widths=[4.0*cm, 4.0*cm, 3.0*cm, 4.5*cm])

    y -= 0.3*cm
    highlight_box(c, 3.0*cm, y - 1.2*cm, W - 5.0*cm, 1.0*cm,
                  bg=BOX_YEL, border=BORDER_YL, title="",
                  lines=["Osmosis special cases: Plasmolysis (cell loses water) | Turgidity (cell gains water) | Flaccidity"])

    draw_footer(c, 5)

    # ── PAGE 6: Cell Wall ────────────────────────────────────────────────────
    new_page(c)
    draw_header_bar(c, "CELL WALL", "Structure · Layers · Plasmodesmata")

    y = H - 2.7*cm

    y = section_heading(c, "CELL WALL (Present in: Plants, Fungi, Bacteria)", y)
    y = bullet(c, "Absent in animal cells and most protozoans", y)
    y = bullet(c, "Main component in plants: CELLULOSE (β-1,4 glycosidic bonds) → microfibrils", y)
    y = bullet(c, "Fungi: Chitin  |  Bacteria: Peptidoglycan  |  Algae: Cellulose + pectin", y)
    y -= 0.2*cm

    y = sub_heading(c, "Layers of Plant Cell Wall:", y)
    rows4 = [
        ["Layer", "Composition", "Location"],
        ["Middle Lamella", "Calcium pectate (pectin)", "Between adjacent cells — cements cells"],
        ["Primary Cell Wall", "Cellulose, hemicellulose, pectin", "Thin, flexible, growing cells"],
        ["Secondary Cell Wall", "Cellulose + lignin", "Thick, rigid, mature cells (wood)"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y, W - 5.0*cm, rows4,
                              col_widths=[4.0*cm, 5.5*cm, 6.0*cm])
    y -= 0.3*cm

    y = sub_heading(c, "Plasmodesmata:", y)
    y = bullet(c, "Cytoplasmic connections between adjacent plant cells through cell wall", y)
    y = bullet(c, "Allow communication, transport of water, nutrients, signals", y)
    y = bullet(c, "Lined by plasma membrane, contain desmotubule (ER-derived tube)", y)

    y -= 0.3*cm
    highlight_box(c, 3.0*cm, y - 1.5*cm, W - 5.0*cm, 1.3*cm,
                  bg=BOX_GRN, border=BORDER_GR, title="★ Important for Exam",
                  lines=["Cellulose → most abundant organic molecule on Earth",
                         "Cell wall gives rigidity & protection; does NOT control what enters/exits (plasma membrane does)"])
    y -= 1.7*cm

    # Difference in Cell walls
    y = section_heading(c, "CELL WALL — Organism Comparison", y)
    rows5 = [
        ["Organism", "Cell Wall Material"],
        ["Bacteria", "Peptidoglycan (murein)"],
        ["Cyanobacteria", "Peptidoglycan + additional layers"],
        ["Fungi", "Chitin (N-acetylglucosamine)"],
        ["Algae", "Cellulose, pectin, silica (diatoms)"],
        ["Higher Plants", "Cellulose + lignin + pectin"],
        ["Animals", "ABSENT"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y - 0.2*cm, W - 5.0*cm, rows5,
                              col_widths=[6.5*cm, 9.0*cm])

    draw_footer(c, 6)

    # ── PAGE 7: Cell Division ────────────────────────────────────────────────
    new_page(c)
    draw_header_bar(c, "CELL DIVISION", "Cell Cycle · Mitosis · Meiosis")

    y = H - 2.7*cm

    y = section_heading(c, "THE CELL CYCLE", y)
    y = bullet(c, "Sequence of events from one cell division to the next", y)
    y -= 0.1*cm

    rows6 = [
        ["Phase", "Sub-phase", "Key Events"],
        ["Interphase (S+G1+G2)", "G1 (Gap 1)", "Cell growth; organelle synthesis; G1 checkpoint"],
        ["", "S (Synthesis)", "DNA replication (each chr. = 2 chromatids)"],
        ["", "G2 (Gap 2)", "Protein synthesis for division; G2 checkpoint"],
        ["Mitotic phase (M)", "Karyokinesis", "Nuclear division (PMAT stages)"],
        ["", "Cytokinesis", "Cytoplasm divides → 2 daughter cells"],
        ["Quiescent phase", "G0", "Cell exits cycle; non-dividing state"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y - 0.1*cm, W - 5.0*cm, rows6,
                              col_widths=[4.5*cm, 3.5*cm, 7.5*cm])
    y -= 0.4*cm

    # Mitosis diagram
    y = section_heading(c, "MITOSIS — Phases (PMAT)", y)
    draw_mitosis_phases(c, 3.0*cm, y - 3.2*cm)
    y -= 3.6*cm

    highlight_box(c, 3.0*cm, y - 2.8*cm, W - 5.0*cm, 2.6*cm,
                  bg=BOX_BLUE, border=BORDER_BL, title="📌 MITOSIS Quick Notes",
                  lines=[
                      "PROPHASE: Chromatin → chromosomes; nucleolus disappears; spindle forms",
                      "METAPHASE: Chromosomes align at metaphase plate (equatorial plate); BEST phase to COUNT chromosomes",
                      "ANAPHASE: Centromeres split; chromatids pulled to poles by spindle; cell elongates",
                      "TELOPHASE: Nuclear envelope reforms; nucleolus reappears; chromosomes decondense",
                      "CYTOKINESIS: Animals = cleavage furrow;  Plants = cell plate (phragmoplast → middle lamella)",
                  ])
    y -= 3.0*cm

    highlight_box(c, 3.0*cm, y - 1.2*cm, W - 5.0*cm, 1.0*cm,
                  bg=BOX_YEL, border=BORDER_YL, title="",
                  lines=["Mitosis result: 2 genetically identical diploid cells | Significance: Growth, repair, asexual reproduction"])

    draw_footer(c, 7)

    # ── PAGE 8: Meiosis ──────────────────────────────────────────────────────
    new_page(c)
    draw_header_bar(c, "MEIOSIS — Reductional Division", "Meiosis I & Meiosis II")

    y = H - 2.7*cm

    y = section_heading(c, "OVERVIEW OF MEIOSIS", y)
    y = bullet(c, "Also called reductional division: diploid (2n) → 4 haploid (n) cells", y)
    y = bullet(c, "Occurs in germ cells (gonads) for gamete formation", y)
    y = bullet(c, "Involves 2 divisions: Meiosis I (reductional) + Meiosis II (equational)", y)
    y = bullet(c, "KEY event: Crossing over (recombination) during Prophase I → genetic variation", y)
    y -= 0.2*cm

    # Meiosis I
    y = section_heading(c, "MEIOSIS I — Prophase I Stages (ZPLDD)", y)
    highlight_box(c, 3.0*cm, y - 3.8*cm, W - 5.0*cm, 3.6*cm,
                  bg=BOX_GRN, border=BORDER_GR, title="PROPHASE I Sub-stages (Mnemonic: 'Z P L D D')",
                  lines=[
                      "Z = LEPTOTENE:  Chromosomes become visible; chromatin condenses",
                      "P = ZYGOTENE:   Synapsis — homologous chromosomes pair (bivalents form)",
                      "L = PACHYTENE:  Crossing over (chiasmata); tetrads clearly visible",
                      "D = DIPLOTENE:  Bivalents begin to separate except at chiasmata",
                      "D = DIAKINESIS: Chromosomes fully condensed; nuclear envelope dissolves",
                  ])
    y -= 4.0*cm

    rows7 = [
        ["Phase (Meiosis I)", "Key Events"],
        ["Metaphase I", "Bivalents align at equatorial plate (NOT individual chromosomes)"],
        ["Anaphase I", "Homologous chromosomes separate to poles (centromeres intact)"],
        ["Telophase I", "2 haploid cells form (each with 2 chromatids per chromosome)"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y - 0.1*cm, W - 5.0*cm, rows7,
                              col_widths=[5.0*cm, 10.5*cm])
    y -= 0.4*cm

    # Meiosis II
    y = section_heading(c, "MEIOSIS II — Equational Division", y)
    y = bullet(c, "Similar to mitosis but starts with haploid cells", y)
    y = bullet(c, "Metaphase II: chromosomes (of n cells) align; Anaphase II: chromatids separate", y)
    y = bullet(c, "Result: 4 genetically diverse haploid cells (gametes)", y)
    y -= 0.2*cm

    rows8 = [
        ["Feature", "Mitosis", "Meiosis"],
        ["Divisions", "1", "2"],
        ["Cells produced", "2 diploid", "4 haploid"],
        ["Genetic makeup", "Identical to parent", "Different (variation)"],
        ["Crossing over", "No", "Yes (Prophase I)"],
        ["Where occurs", "Somatic cells", "Germ cells (gonads)"],
        ["Significance", "Growth, repair", "Sexual reproduction, variation"],
    ]
    y = draw_comparison_table(c, 3.0*cm, y - 0.2*cm, W - 5.0*cm, rows8,
                              col_widths=[4.5*cm, 5.5*cm, 5.5*cm])

    y -= 0.4*cm
    highlight_box(c, 3.0*cm, y - 1.4*cm, W - 5.0*cm, 1.2*cm,
                  bg=BOX_RED, border=BORDER_RD, title="",
                  lines=["★ Significance of Meiosis: Maintains chromosome number across generations;",
                         "   Crossing over → genetic recombination → variation → evolution"])
    draw_footer(c, 8)

    # ── PAGE 9: Important Short Topics + Quick Revision ─────────────────────
    new_page(c)
    draw_header_bar(c, "IMPORTANT TOPICS & QUICK REVISION", "Frequently Asked in Exams")

    y = H - 2.7*cm

    y = section_heading(c, "ENDOMEMBRANE SYSTEM", y)
    y = bullet(c, "Comprises: ER + Golgi + Lysosomes + Vacuoles + Plasma membrane", y)
    y = bullet(c, "All interconnected by vesicle transport; coordinate cell secretion & digestion", y)
    y = bullet(c, "Mitochondria & Chloroplasts are NOT part of endomembrane system", y)
    y -= 0.2*cm

    y = section_heading(c, "SEMI-AUTONOMOUS ORGANELLES", y)
    highlight_box(c, 3.0*cm, y - 1.8*cm, W - 5.0*cm, 1.6*cm,
                  bg=BOX_BLUE, border=BORDER_BL, title="",
                  lines=[
                      "Mitochondria & Chloroplasts = Semi-autonomous because:",
                      "  ✔ Own circular DNA (like prokaryotes)",
                      "  ✔ Own 70S ribosomes (prokaryotic type)",
                      "  ✔ Can self-replicate by binary fission",
                      "  ✗ Still need nuclear genome for many proteins → NOT fully autonomous",
                  ])
    y -= 2.0*cm

    y = section_heading(c, "IMPORTANT ONE-LINERS (High Yield)", y)
    one_liners = [
        "★ Largest cell: Ostrich egg (macrolecithal egg)",
        "★ Smallest cell: Mycoplasma (PPLO — 0.1 µm)",
        "★ Longest cell: Nerve cell (up to 1 metre)",
        "★ Largest organelle: Nucleus",
        "★ Smallest organelle: Ribosome",
        "★ Power house of cell: Mitochondria",
        "★ Suicide bag: Lysosome",
        "★ Kitchen of cell: Chloroplast",
        "★ Traffic policeman: Golgi apparatus",
        "★ Security guard: Cell membrane",
        "★ Prokaryote ribosomes: 70S | Eukaryote: 80S | Mito/Chloro: 70S",
        "★ Cell plate formed by Golgi vesicles in plant cytokinesis",
        "★ Tonoplast = membrane of vacuole",
        "★ Phragmoplast = spindle fibres in plant cytokinesis",
        "★ Peroxisomes: contain catalase; detoxify H₂O₂; present in liver cells",
        "★ Microtubules: made of tubulin; form spindle, cilia, flagella",
        "★ Microfilaments: made of actin; involved in cell motility & contraction",
        "★ Intermediate filaments: mechanical strength; made of vimentin, keratin",
    ]
    for ol in one_liners:
        y = body_text(c, ol, y, indent=3.2*cm, font_size=8.8)
        if y < 2.0*cm:
            break

    draw_footer(c, 9)

    # ── PAGE 10: Mnemonics + Exam Tips ──────────────────────────────────────
    new_page(c)
    draw_header_bar(c, "MNEMONICS & EXAM TIPS", "Score Full Marks!")

    y = H - 2.7*cm

    y = section_heading(c, "🧠 MEMORY TRICKS & MNEMONICS", y)

    highlight_box(c, 3.0*cm, y - 1.2*cm, W - 5.0*cm, 1.0*cm,
                  bg=BOX_YEL, border=BORDER_YL, title="Mitosis stages = PMAT",
                  lines=["P-M-A-T : 'People Meet And Talk'  (Prophase→Metaphase→Anaphase→Telophase)"])
    y -= 1.4*cm

    highlight_box(c, 3.0*cm, y - 1.2*cm, W - 5.0*cm, 1.0*cm,
                  bg=BOX_GRN, border=BORDER_GR, title="Prophase I stages = LZPDD",
                  lines=["Leptotene-Zygotene-Pachytene-Diplotene-Diakinesis",
                         "Mnemonic: 'Lovely Zebras Play Daily Darts'"])
    y -= 1.4*cm

    highlight_box(c, 3.0*cm, y - 1.2*cm, W - 5.0*cm, 1.0*cm,
                  bg=BOX_BLUE, border=BORDER_BL, title="Ribosome subunits",
                  lines=["70S = 50S+30S (prokaryotes)  |  Remember: 50+30 ≠ 70 (Svedberg units are NOT additive!)"])
    y -= 1.4*cm

    highlight_box(c, 3.0*cm, y - 1.2*cm, W - 5.0*cm, 1.0*cm,
                  bg=BOX_RED, border=BORDER_RD, title="Differences in cell walls",
                  lines=["'Beware Clever People Always' = Bacteria(peptidoglycan), Chitin(fungi), Pectin(middle lamella), (plant)"])
    y -= 1.6*cm

    y = section_heading(c, "📝 PREVIOUS YEAR EXAM QUESTIONS (Important)", y)
    qs = [
        "Q1. What is the difference between prokaryotic and eukaryotic cells?",
        "Q2. Describe the structure of mitochondria with a labelled diagram.",
        "Q3. Explain the fluid mosaic model of plasma membrane.",
        "Q4. Describe the events of Prophase I of Meiosis I.",
        "Q5. What are plasmodesmata? State their functions.",
        "Q6. Differentiate between mitosis and meiosis. (5 marks table)",
        "Q7. Why are mitochondria and chloroplasts called semi-autonomous organelles?",
        "Q8. Write the functions of Golgi apparatus.",
        "Q9. What is cell cycle? Describe G1, S and G2 phases.",
        "Q10. Compare plant and animal cell (with diagram).",
    ]
    for q in qs:
        y = body_text(c, q, y, indent=3.2*cm, font_size=9, col=H1_COL, bold=True)
        y -= 0.05*cm

    y -= 0.2*cm
    y = section_heading(c, "✅ EXAM DAY TIPS", y)
    tips = [
        "Always draw diagrams with sharp pencil first; label neatly with scale bar",
        "Use blue/black pen for writing; highlight headings with light colours",
        "In 5-mark questions: always include a comparison table OR diagram",
        "Learn the one-liners on Page 9 — direct 1-mark questions!",
        "Cross-check: mitochondria has cristae; chloroplast has thylakoids (grana)",
        "Meiosis Prophase I = most complex; break it into LZPDD for easy recall",
    ]
    for t in tips:
        y = bullet(c, t, y, col=HexColor("#196F3D"), bullet_col=HexColor("#196F3D"))

    draw_footer(c, 10)

    c.save()
    print(f"PDF saved to: {path}")


if __name__ == "__main__":
    build_pdf("/home/daytona/workspace/cell-notes/Cell_Chapter_Class11_Topper_Notes.pdf")

cd /home/daytona/workspace/cell-notes && python generate_notes.py 2>&1

~/cell-notes/generate_notes.py

Successfully replaced 1 instance(s) of the string in '/home/daytona/workspace/cell-notes/generate_notes.py'

cd /home/daytona/workspace/cell-notes && python generate_notes.py 2>&1

ls -lh /home/daytona/workspace/cell-notes/Cell_Chapter_Class11_Topper_Notes.pdf