import openpyxl
from openpyxl.styles import (
    PatternFill, Font, Alignment, Border, Side, GradientFill
)
from openpyxl.utils import get_column_letter
from openpyxl.styles.numbers import FORMAT_TEXT

wb = openpyxl.Workbook()
ws = wb.active
ws.title = "Physiological Changes"

# ── Color Palette ──────────────────────────────────────────────────────────
COLORS = {
    "navy":      "1B2A4A",
    "white":     "FFFFFF",
    "cns":       "6A0DAD",   # purple
    "cns_light": "EDE7F6",
    "cvs":       "C0392B",   # red
    "cvs_light": "FDEDEC",
    "resp":      "1A6B8A",   # teal
    "resp_light":"E8F4F8",
    "heme":      "D35400",   # orange
    "heme_light":"FEF9E7",
    "renal":     "1E8449",   # green
    "renal_light":"E9F7EF",
    "gi":        "8E44AD",   # violet
    "gi_light":  "F5EEF8",
    "endo":      "2874A6",   # blue
    "endo_light":"EBF5FB",
    "msk":       "6D4C41",   # brown
    "msk_light": "EFEBE9",
    "skin":      "B7950B",   # gold
    "skin_light":"FEF9E7",
    "inc":       "D5F5E3",   # light green tint for ↑
    "dec":       "FADBD8",   # light red tint for ↓
    "neut":      "EBF5FB",   # light blue for ~no change
    "row_alt":   "F7F9FC",
    "header_row":"2C3E50",
}

def mkfill(hex_color):
    return PatternFill("solid", fgColor=hex_color)

def mkfont(bold=False, color="000000", size=10, italic=False):
    return Font(bold=bold, color=color, size=size, italic=italic, name="Arial")

def mkalign(h="center", v="center", wrap=True):
    return Alignment(horizontal=h, vertical=v, wrap_text=wrap)

thin = Side(style="thin", color="CCCCCC")
med  = Side(style="medium", color="888888")

def thin_border():
    return Border(left=thin, right=thin, top=thin, bottom=thin)

def med_border():
    return Border(left=med, right=med, top=med, bottom=med)

# ─── Title ────────────────────────────────────────────────────────────────
ws.merge_cells("A1:F1")
ws["A1"] = "PHYSIOLOGICAL CHANGES DURING PREGNANCY"
ws["A1"].fill = mkfill(COLORS["navy"])
ws["A1"].font = mkfont(bold=True, color=COLORS["white"], size=16)
ws["A1"].alignment = mkalign()
ws.row_dimensions[1].height = 36

ws.merge_cells("A2:F2")
ws["A2"] = "Based on DC Dutta's Textbook of Obstetrics  |  Ref: Morgan & Mikhail's Clinical Anesthesiology 7e, Braunwald's Heart Disease, Creasy & Resnik's Maternal-Fetal Medicine"
ws["A2"].fill = mkfill("3D566E")
ws["A2"].font = mkfont(italic=True, color=COLORS["white"], size=9)
ws["A2"].alignment = mkalign()
ws.row_dimensions[2].height = 20

# ─── Column Headers ───────────────────────────────────────────────────────
headers = ["System", "Parameter", "Change", "Magnitude / Value", "Mechanism / Notes", "Clinical Significance"]
col_widths = [18, 26, 10, 28, 52, 44]

for i, (h, w) in enumerate(zip(headers, col_widths), 1):
    c = ws.cell(row=3, column=i, value=h)
    c.fill = mkfill(COLORS["header_row"])
    c.font = mkfont(bold=True, color=COLORS["white"], size=11)
    c.alignment = mkalign()
    c.border = thin_border()
    ws.column_dimensions[get_column_letter(i)].width = w

ws.row_dimensions[3].height = 26

# ─── Data ─────────────────────────────────────────────────────────────────
# Format: (system, system_color, system_light, parameter, arrow, magnitude, mechanism, clinical)
data = [
    # ═══ CARDIOVASCULAR ═══
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Blood Volume", "↑", "+35–45% by 32–34 wks",
     "Increased EPO → RBC mass ↑ 20–30%; plasma volume ↑ 40–55%; plasma rises more → dilutional anaemia",
     "Hb falls to ~10.5 g/dL = physiological anaemia; supports uteroplacental flow"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Plasma Volume", "↑", "+50–55%",
     "Aldosterone & oestrogen-mediated Na+ and water retention; peak at 32–34 weeks",
     "Haemodilution of all blood elements; important in haemorrhage tolerance"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Cardiac Output", "↑", "+40–50% (peaks ~28–32 wks)",
     "HR ↑ 15–20 bpm + stroke volume ↑ 30%; further ↑ 60–80% during labour/delivery",
     "Heart disease may decompensate; greatest strain immediately postpartum"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Heart Rate", "↑", "+15–20 bpm (≈+20%)",
     "Progesterone, autonomic shift; sinus tachycardia is normal",
     "Baseline tachycardia may mask pathological tachyarrhythmias"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Stroke Volume", "↑", "+30%",
     "Increased preload from plasma volume expansion; decreased afterload",
     "Combined with HR rise → large CO increase"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Systolic BP", "↓", "-5 to -10 mmHg (1st/2nd trim)",
     "Peripheral vasodilation due to progesterone & NO; returns to baseline by 3rd trimester",
     "May mimic hypotension; DBP falls more than SBP"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Diastolic BP", "↓", "-10 to -15 mmHg",
     "Marked peripheral vasodilation; nadir at 24 wks; rises back at term",
     "Wide pulse pressure; useful in diagnosing PIH/pre-eclampsia"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Peripheral Vascular Resistance", "↓", "-15 to -20%",
     "Progesterone, oestrogen, prostacyclin, NO-mediated smooth muscle relaxation",
     "Protective against hypertension; low SVR mimics septic physiology"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "Pulmonary Vascular Resistance", "↓", "-30%",
     "Pulmonary vasodilation parallels systemic changes",
     "Important in pre-existing pulmonary hypertension management"),
    ("CARDIOVASCULAR", "cvs", "cvs_light",
     "IVC Compression (supine)", "↑ risk", "After 20 weeks",
     "Gravid uterus compresses IVC → ↓ venous return → ↓ CO; aortocaval compression syndrome",
     "Supine hypotension in ~5% (pallor, nausea, syncope); left lateral tilt mandatory"),
    # ═══ RESPIRATORY ═══
    ("RESPIRATORY", "resp", "resp_light",
     "Tidal Volume (VT)", "↑", "+40% (~500→700 mL)",
     "Progesterone stimulates respiratory centre; diaphragm elevation by 4 cm offsets",
     "Increased minute ventilation → respiratory alkalosis"),
    ("RESPIRATORY", "resp", "resp_light",
     "Respiratory Rate", "↑", "+15% (16→18–19/min)",
     "Progesterone-mediated central respiratory drive increase",
     "Tachypnoea > 20/min at rest is abnormal"),
    ("RESPIRATORY", "resp", "resp_light",
     "Minute Ventilation (MV)", "↑", "+50%",
     "Mainly VT increase; hyperventilation is physiological",
     "Leads to chronic compensated respiratory alkalosis"),
    ("RESPIRATORY", "resp", "resp_light",
     "Functional Residual Capacity (FRC)", "↓", "-20 to -25%",
     "Diaphragm elevation by 4 cm due to uterus; closing volume may exceed FRC in supine",
     "Rapid desaturation on apnoea; prone to atelectasis; difficult intubation risk"),
    ("RESPIRATORY", "resp", "resp_light",
     "Residual Volume (RV)", "↓", "-20%",
     "Diaphragm elevation; reduced chest wall compliance",
     "Part of FRC reduction"),
    ("RESPIRATORY", "resp", "resp_light",
     "Inspiratory Capacity (IC)", "↑", "+5–10%",
     "Compensatory increase; TLC essentially unchanged",
     "Maintains adequate tidal breathing despite diaphragm elevation"),
    ("RESPIRATORY", "resp", "resp_light",
     "TLC", "↓ slightly", "-5%",
     "Minimal change; IC ↑ partially compensates RV+ERV ↓",
     "FVC and FEV1 not significantly changed"),
    ("RESPIRATORY", "resp", "resp_light",
     "Airway Resistance", "↓", "-35%",
     "Progesterone-mediated bronchodilation; mucosal oedema increases upper airway resistance",
     "Asthma may improve; upper airway oedema worsens intubation difficulty"),
    ("RESPIRATORY", "resp", "resp_light",
     "PaO₂", "↑", "+10% (~104–108 mmHg)",
     "Hyperventilation increases alveolar O₂; progesterone raises hypoxic drive",
     "Protects fetus; falls significantly in supine position"),
    ("RESPIRATORY", "resp", "resp_light",
     "PaCO₂", "↓", "-15% (40→28–32 mmHg)",
     "Hyperventilation; CO₂ eliminated faster; gradient favours fetal CO₂ transfer",
     "Respiratory alkalosis; compensated by renal HCO₃ excretion"),
    ("RESPIRATORY", "resp", "resp_light",
     "HCO₃", "↓", "-15% (~18–22 mEq/L)",
     "Renal compensation for respiratory alkalosis; pre-pregnant norm ~24 mEq/L",
     "ABG interpretation: normal in pregnancy = slightly alkalotic pH ~7.44"),
    ("RESPIRATORY", "resp", "resp_light",
     "O₂ Consumption", "↑", "+20–50%",
     "Fetal metabolic demand + increased maternal cardiac/respiratory work",
     "Rapid hypoxaemia during apnoea; pre-oxygenation essential before GA"),
    # ═══ HAEMATOLOGICAL ═══
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "Haemoglobin", "↓", "~11.5–12 g/dL (non-preg ~13)",
     "Plasma volume ↑ > RBC mass ↑ → dilutional; physiological not pathological if ≥10.5",
     "WHO defines anaemia in pregnancy as Hb < 11 g/dL (1st/3rd trim) or < 10.5 (2nd trim)"),
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "RBC Mass", "↑", "+20–30%",
     "Erythropoietin ↑ (especially with iron supplementation); iron demand ~1000 mg total",
     "Iron and folate supplementation essential; without iron, RBC rise is blunted"),
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "Platelets", "↓ slightly", "-10% (gestational thrombocytopenia)",
     "Dilution + increased consumption; rarely pathological if >100,000",
     "Gestational thrombocytopenia: mild (>70k), no foetal risk; resolves postpartum"),
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "Clotting Factors", "↑", "+30–250% (I, VII, VIII, IX, X, XII)",
     "Oestrogen-driven hepatic synthesis ↑; fibrinogen rises to 400–600 mg/dL",
     "Hypercoagulable state: DVT/PE risk ↑ 5×; Virchow's triad present"),
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "Fibrinogen", "↑", "400–600 mg/dL (norm 200–400)",
     "Markedly elevated; contributes to raised ESR in pregnancy",
     "High ESR is normal in pregnancy; elevated D-dimer unreliable for DVT diagnosis"),
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "Protein S / Antithrombin III", "↓", "Protein S ↓ ~55%",
     "Acquired thrombophilia state in pregnancy; protein C essentially unchanged",
     "Thromboprophylaxis critical in high-risk cases; warfarin teratogenic"),
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "WBC", "↑", "Up to 15,000/mm³ (labour: up to 25,000)",
     "Demargination + increased production; mainly neutrophilia",
     "Leukocytosis is normal; cannot reliably diagnose infection by WBC alone"),
    ("HAEMATOLOGICAL", "heme", "heme_light",
     "ESR", "↑", "Markedly elevated",
     "Elevated fibrinogen and globulins cause increased rouleaux formation",
     "ESR not useful diagnostically in pregnancy"),
    # ═══ RENAL ═══
    ("RENAL", "renal", "renal_light",
     "Renal Blood Flow (RBF)", "↑", "+50–80% by 16 wks",
     "Renal vasodilation parallels systemic vasodilation; relaxin mediates early rise",
     "Returns to normal by late 3rd trimester; important for drug clearance"),
    ("RENAL", "renal", "renal_light",
     "GFR", "↑", "+50% (120→180 mL/min)",
     "Increased RBF + glomerular hyperfiltration; filtration fraction also increases",
     "Serum creatinine, urea, uric acid fall – 'normal' values indicate renal impairment in pregnancy"),
    ("RENAL", "renal", "renal_light",
     "Serum Creatinine", "↓", "0.4–0.6 mg/dL (norm ~0.8)",
     "Dilution + increased GFR; >0.8 mg/dL may indicate renal pathology",
     "Interpret creatinine cautiously; lower normal range in pregnancy"),
    ("RENAL", "renal", "renal_light",
     "Serum Urea / BUN", "↓", "~8–10 mg/dL (norm ~13)",
     "Increased filtration + anabolic state",
     "BUN > 13 should raise concern in pregnancy"),
    ("RENAL", "renal", "renal_light",
     "Glycosuria", "Present", "Normally absent in non-pregnant",
     "Tubular reabsorptive capacity not increased despite ↑ GFR → glucose spills",
     "Glycosuria is normal in pregnancy; screen for GDM with OGTT, not dipstick"),
    ("RENAL", "renal", "renal_light",
     "Proteinuria", "↑ slightly", "Up to 300 mg/24 h",
     "Increased glomerular filtration; ≤300 mg/24 h is upper limit of normal",
     ">300 mg/24h = significant proteinuria; cardinal feature of pre-eclampsia"),
    ("RENAL", "renal", "renal_light",
     "Ureteric Dilation (Hydronephrosis)", "↑", "Right > Left",
     "Progesterone-mediated smooth muscle relaxation + mechanical compression by uterus",
     "Urinary stasis → ↑ UTI / pyelonephritis risk; asymmetric right-sided hydronephrosis is normal"),
    ("RENAL", "renal", "renal_light",
     "Bladder Capacity", "↓", "Reduced, urgency common",
     "Mechanical pressure from uterus; vesicoureteric reflux more common",
     "Frequency and urgency are physiological; screen for UTI regardless"),
    # ═══ GASTROINTESTINAL ═══
    ("GASTROINTESTINAL", "gi", "gi_light",
     "Gastric Motility", "↓", "Delayed gastric emptying",
     "Progesterone → smooth muscle relaxation → ↓ motility; displacement of stomach by uterus",
     "↑ risk of aspiration during GA (Mendelson's syndrome); RSI mandatory"),
    ("GASTROINTESTINAL", "gi", "gi_light",
     "Lower Oesophageal Sphincter (LOS) Tone", "↓", "Reduced barrier pressure",
     "Progesterone relaxes LOS; uterus elevates intragastric pressure",
     "Heartburn (pyrosis) universal; GERD; aspiration risk ↑ under GA"),
    ("GASTROINTESTINAL", "gi", "gi_light",
     "Gastric Acid Secretion", "↓ (1st/2nd trim)", "Hypochlorhydria",
     "hCG inhibits gastrin; 3rd trimester acid may ↑ due to placental gastrin",
     "Nausea/vomiting of pregnancy (NVP); peaks at 6–12 wks"),
    ("GASTROINTESTINAL", "gi", "gi_light",
     "Small Bowel Transit", "↓", "Prolonged transit time",
     "Progesterone reduces peristalsis throughout GI tract",
     "Constipation common; ↑ water/iron absorption; ↑ drug absorption from gut"),
    ("GASTROINTESTINAL", "gi", "gi_light",
     "Haemorrhoids", "↑ risk", "Common",
     "IVC compression → venous congestion; constipation + straining",
     "Symptomatic treatment; resolves postpartum in most cases"),
    ("GASTROINTESTINAL", "gi", "gi_light",
     "Liver (size, function)", "~", "Size unchanged",
     "Liver position displaced; ALP ↑ (placental isoform); GGT, ALT, AST normal",
     "Elevated ALP is normal; raised ALT/AST is pathological (e.g., HELLP, ICP)"),
    ("GASTROINTESTINAL", "gi", "gi_light",
     "Gallbladder", "↓ motility", "Bile stasis",
     "Progesterone reduces gallbladder emptying; bile more lithogenic (↑ cholesterol)",
     "Cholelithiasis risk ↑; pregnancy is gallstone-prone state ('stone age of life')"),
    # ═══ ENDOCRINE ═══
    ("ENDOCRINE", "endo", "endo_light",
     "hCG", "↑ then ↓", "Peaks 8–10 wks, then ↓",
     "Produced by syncytiotrophoblast; maintains corpus luteum progesterone till 10 wks",
     "Basis of pregnancy test; extremely high in molar pregnancy/choriocarcinoma"),
    ("ENDOCRINE", "endo", "endo_light",
     "Progesterone", "↑", "~150 ng/mL at term (20× normal)",
     "Corpus luteum (1st trim) → placenta (from 10 wks); essential for uterine quiescence",
     "Sedating; responsible for ↓ MAC, smooth muscle relaxation, nasal congestion, GI effects"),
    ("ENDOCRINE", "endo", "endo_light",
     "Oestrogens (estriol)", "↑", "1000× non-pregnant levels at term",
     "Placenta uses DHEAS from fetal adrenal; oestradiol and oestriol rise",
     "Drives uterine growth, breast development, SHBG rise; monitoring of fetoplacental unit"),
    ("ENDOCRINE", "endo", "endo_light",
     "Thyroid (Total T3/T4)", "↑", "↑ (bound); free T4 normal",
     "hCG stimulates TSH receptor (weak agonist); TBG rises (oestrogen ↑); TSH may ↓ in 1st trim",
     "Interpret TFTs with pregnancy-specific ranges; TSH 0.1–2.5 mU/L acceptable in 1st trim"),
    ("ENDOCRINE", "endo", "endo_light",
     "Insulin Resistance", "↑", "Increases progressively from 2nd trim",
     "HPL (human placental lactogen), progesterone, cortisol → anti-insulin effect; fasting glucose ↓",
     "GDM risk in predisposed; OGTT screen at 24–28 wks; fasting glucose lower in normal pregnancy"),
    ("ENDOCRINE", "endo", "endo_light",
     "Cortisol", "↑", "Total ↑↑; free cortisol ↑",
     "CBG rises (oestrogen effect); ACTH from placenta; normal Cushing's-like picture",
     "Striae gravidarum; impaired wound healing; immune modulation"),
    ("ENDOCRINE", "endo", "endo_light",
     "Prolactin", "↑", "10× by term",
     "Oestrogen-driven pituitary lactotroph hypertrophy; pituitary doubles in size",
     "Prepares breast for lactation; galactorrhoea; pituitary enlargement → visual field risk"),
    ("ENDOCRINE", "endo", "endo_light",
     "Relaxin", "↑", "Peak at 10 wks; persists",
     "Corpus luteum + placenta; relaxes pelvic ligaments, cervix, and systemic vasodilation",
     "Pelvic girdle pain (symphysis pubis dysfunction); facilitates delivery"),
    ("ENDOCRINE", "endo", "endo_light",
     "Aldosterone / RAAS", "↑", "↑↑ (10× non-pregnant)",
     "Oestrogen ↑ angiotensinogen; ↑ renin; ↑ angiotensin; ↑ aldosterone → Na/water retention",
     "Physiological hyperaldosteronism; suppressed in pre-eclampsia (paradox)"),
    # ═══ CNS / NEUROLOGICAL ═══
    ("CNS / NEUROLOGICAL", "cns", "cns_light",
     "MAC (Anaesthetic)", "↓", "-40% by term",
     "Progesterone (sedating); β-endorphin surge in labour; returns to normal by day 3 postpartum",
     "Requires lower GA doses; volatile agents effective at reduced concentrations"),
    ("CNS / NEUROLOGICAL", "cns", "cns_light",
     "Local Anaesthetic Sensitivity", "↑", "Dose reduced by ~30%",
     "Engorgement of epidural venous plexus (IVC compression) ↓ epidural space volume; hormonal neural sensitivity",
     "Regional block spreads further and higher; reduce epidural/spinal doses"),
    ("CNS / NEUROLOGICAL", "cns", "cns_light",
     "Epidural Venous Plexus", "↑ engorgement", "From 2nd trimester",
     "IVC obstruction by uterus → collateral drainage via epidural veins → epidural vascular congestion",
     "↑ risk of intravascular catheter placement; aspiration of blood before epidural injection essential"),
    ("CNS / NEUROLOGICAL", "cns", "cns_light",
     "Mood / Cognition", "Variable", "Mood lability, 'pregnancy brain'",
     "Hormonal changes, sleep deprivation, neuroplastic changes; hippocampal grey matter ↓ (1st time)",
     "Prenatal depression/anxiety common; screen routinely"),
    # ═══ MUSCULOSKELETAL ═══
    ("MUSCULOSKELETAL", "msk", "msk_light",
     "Pelvic Ligaments", "↑ laxity", "Relaxation from relaxin",
     "Relaxin + progesterone → symphysis pubis and SI joint laxity from 1st trimester",
     "Symphysis pubis diastasis; pelvic girdle pain; postural instability"),
    ("MUSCULOSKELETAL", "msk", "msk_light",
     "Lumbar Lordosis", "↑", "Progressive",
     "Anterior shift of centre of gravity due to gravid uterus; compensatory lordosis",
     "Low back pain in 50–80%; muscle strain; altered gait"),
    ("MUSCULOSKELETAL", "msk", "msk_light",
     "Weight Gain", "↑", "Recommended: 11–16 kg (normal BMI)",
     "Fetus ~3.3 kg; placenta ~0.6 kg; liquor ~0.8 kg; uterus ~0.9 kg; breasts ~0.4 kg; blood/fluid ~3–4 kg",
     "Excess gain → GDM, pre-eclampsia, macrosomia; inadequate gain → FGR"),
    # ═══ SKIN ═══
    ("SKIN / DERMATOLOGY", "skin", "skin_light",
     "Pigmentation", "↑", "Melasma, linea nigra",
     "↑ MSH (melanocyte-stimulating hormone); oestrogen and progesterone stimulate melanocytes",
     "Melasma ('mask of pregnancy'); linea nigra; darkening of nipples, axillae, genitalia"),
    ("SKIN / DERMATOLOGY", "skin", "skin_light",
     "Striae Gravidarum", "Appear", "Abdomen, breasts, thighs",
     "Mechanical stretching + cortisol-mediated collagen disruption in dermis",
     "Irreversible; creams minimally effective; worsened by excess weight gain"),
    ("SKIN / DERMATOLOGY", "skin", "skin_light",
     "Spider Angiomata / Palmar Erythema", "↑", "Common in 2nd trim onwards",
     "Oestrogen-mediated vasodilation and angiogenesis",
     "Normal finding; distinguish from signs of hepatic failure"),
    ("SKIN / DERMATOLOGY", "skin", "skin_light",
     "Hair", "↑ thickness", "Anagen prolonged; shedding ↓",
     "High oestrogen prolongs hair growth phase; mass telogen effluvium postpartum",
     "Postpartum hair loss (telogen effluvium) at 3–6 months is normal and self-limiting"),
]

arrow_fill = {
    "↑": mkfill("D5F5E3"),
    "↓": mkfill("FADBD8"),
    "~": mkfill(COLORS["neut"]),
    "↑ risk": mkfill("FDEBD0"),
    "↓ motility": mkfill("FADBD8"),
    "Variable": mkfill(COLORS["neut"]),
    "Present": mkfill("FDEBD0"),
    "Appear": mkfill("FDEBD0"),
    "↑ then ↓": mkfill("EBF5FB"),
    "↑ engorgement": mkfill("FADBD8"),
    "↑ laxity": mkfill("FDEBD0"),
    "↑ thickness": mkfill("D5F5E3"),
    "↓ (1st/2nd trim)": mkfill("FADBD8"),
}

row = 4
current_system = None
system_start = 4

for entry in data:
    system, sys_color, sys_light, param, arrow, magnitude, mechanism, clinical = entry

    # System merge – group rows for same system
    fill = mkfill(COLORS[sys_light])
    sys_fill = mkfill(COLORS[sys_color])

    c_sys = ws.cell(row=row, column=1, value=system if system != current_system else "")
    c_sys.fill = sys_fill
    c_sys.font = mkfont(bold=True, color=COLORS["white"], size=10)
    c_sys.alignment = mkalign()
    c_sys.border = thin_border()

    c_param = ws.cell(row=row, column=2, value=param)
    c_param.fill = fill
    c_param.font = mkfont(bold=True, size=10)
    c_param.alignment = mkalign(h="left")
    c_param.border = thin_border()

    arrow_cell = ws.cell(row=row, column=3, value=arrow)
    arrow_cell.fill = arrow_fill.get(arrow, mkfill(COLORS["neut"]))
    arrow_cell.font = mkfont(bold=True, size=14, color="2C3E50")
    arrow_cell.alignment = mkalign()
    arrow_cell.border = thin_border()

    c_mag = ws.cell(row=row, column=4, value=magnitude)
    c_mag.fill = fill
    c_mag.font = mkfont(size=10)
    c_mag.alignment = mkalign(h="left")
    c_mag.border = thin_border()

    c_mech = ws.cell(row=row, column=5, value=mechanism)
    c_mech.fill = fill
    c_mech.font = mkfont(size=9, italic=False)
    c_mech.alignment = mkalign(h="left")
    c_mech.border = thin_border()

    c_clin = ws.cell(row=row, column=6, value=clinical)
    c_clin.fill = mkfill("FDFEFE")
    c_clin.font = mkfont(size=9, color="1A252F")
    c_clin.alignment = mkalign(h="left")
    c_clin.border = thin_border()

    ws.row_dimensions[row].height = 45
    current_system = system
    row += 1

# ─── Legend Row ───────────────────────────────────────────────────────────
ws.merge_cells(f"A{row}:F{row}")
legend = ws.cell(row=row, column=1,
    value="LEGEND:  ↑ = Increase (green)   |   ↓ = Decrease (red)   |   ~ = Unchanged (blue)   |   ↑ risk / Present = Notable change (orange)")
legend.fill = mkfill(COLORS["navy"])
legend.font = mkfont(italic=True, color=COLORS["white"], size=9)
legend.alignment = mkalign()
ws.row_dimensions[row].height = 18

# ─── Freeze panes ─────────────────────────────────────────────────────────
ws.freeze_panes = "A4"

# ─── Sheet tab color ──────────────────────────────────────────────────────
ws.sheet_properties.tabColor = "1B2A4A"

# ─── Auto-filter ──────────────────────────────────────────────────────────
ws.auto_filter.ref = f"A3:F{row - 1}"

out_path = "/home/daytona/workspace/pregnancy-physiology/Physiological_Changes_Pregnancy_DC_Dutta.xlsx"
wb.save(out_path)
print(f"Saved: {out_path}")
print(f"Total data rows: {row - 4}")

Successfully replaced 1 instance(s) of the string in '/home/daytona/workspace/pregnancy-physiology/make_chart.py'