Annotated Peak Stem

import matplotlib.pyplot as plt
import numpy as np

COLORS = {
    'stem': '#6366F1',
    'highlight': '#EF4444',
    'background': '#FFFFFF',
    'text': '#1E293B',
    'text_muted': '#64748B',
    'grid': '#F1F5F9',
}

x = np.arange(1, 11)
y = [35, 42, 38, 55, 48, 72, 65, 58, 62, 70]
highlight_idx = 5  # Peak

fig, ax = plt.subplots(figsize=(10, 6), dpi=100)
ax.set_facecolor(COLORS['background'])
fig.patch.set_facecolor(COLORS['background'])

for i, (xi, yi) in enumerate(zip(x, y)):
    color = COLORS['highlight'] if i == highlight_idx else COLORS['stem']
    ax.plot([xi, xi], [0, yi], color=color, linewidth=2.5, alpha=0.7, zorder=2)
    ax.scatter(xi, yi, s=150 if i == highlight_idx else 100, c=color, alpha=0.2, zorder=3)
    ax.scatter(xi, yi, s=80 if i == highlight_idx else 50, c=color, 
               edgecolors='white', linewidths=2, zorder=4)

# Annotation for peak
ax.annotate(f'Peak: {y[highlight_idx]}', xy=(x[highlight_idx], y[highlight_idx]),
            xytext=(x[highlight_idx] + 1.5, y[highlight_idx] + 8),
            fontsize=10, fontweight='bold', color=COLORS['highlight'],
            arrowprops=dict(arrowstyle='->', color=COLORS['highlight'], lw=1.5))

ax.axhline(0, color=COLORS['text'], linewidth=1, zorder=1)

ax.spines['top'].set_visible(False)
ax.spines['right'].set_visible(False)
ax.spines['left'].set_color(COLORS['grid'])
ax.spines['bottom'].set_color(COLORS['grid'])

ax.yaxis.grid(True, color=COLORS['grid'], linewidth=1, zorder=0)
ax.set_axisbelow(True)
ax.tick_params(axis='both', colors=COLORS['text_muted'], labelsize=9, length=0, pad=8)

ax.set_xlim(0, 12)
ax.set_ylim(0, 90)
ax.set_xlabel('Month', fontsize=10, color=COLORS['text'], labelpad=10)
ax.set_ylabel('Value', fontsize=10, color=COLORS['text'], labelpad=10)

plt.tight_layout()
plt.show()