Stacked Stairs

import matplotlib.pyplot as plt
import numpy as np

COLORS = {
    'layer1': '#6366F1',
    'layer2': '#10B981',
    'layer3': '#F59E0B',
    'background': '#FFFFFF',
    'text': '#1E293B',
    'text_muted': '#64748B',
    'grid': '#F1F5F9'
}

edges = np.arange(11)
y1 = np.array([2, 3, 4, 3, 4, 5, 4, 3, 4, 3])
y2 = np.array([1.5, 2, 2.5, 3, 2.5, 2, 3, 2.5, 2, 2.5])
y3 = np.array([1, 1.5, 2, 1.5, 2, 1.5, 2, 2, 1.5, 2])

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

ax.stairs(y1, edges, fill=True, alpha=0.6, facecolor=COLORS['layer1'], linewidth=2, edgecolor=COLORS['layer1'], label='Infrastructure')
ax.stairs(y1 + y2, edges, fill=True, alpha=0.6, facecolor=COLORS['layer2'], linewidth=2, edgecolor=COLORS['layer2'], baseline=y1, label='Platform')
ax.stairs(y1 + y2 + y3, edges, fill=True, alpha=0.6, facecolor=COLORS['layer3'], linewidth=2, edgecolor=COLORS['layer3'], baseline=y1+y2, label='Application')

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, 10)
ax.set_ylim(0, 10)
ax.set_xlabel('Sprint', fontsize=10, color=COLORS['text'], labelpad=10)
ax.set_ylabel('Cost ($K)', fontsize=10, color=COLORS['text'], labelpad=10)
ax.legend(loc='upper center', bbox_to_anchor=(0.5, -0.12), ncol=3, frameon=False, fontsize=10, labelcolor=COLORS['text_muted'])

plt.tight_layout()
plt.show()