Read the following passage:
In the heart of the forest, sunlight filtered through the leaves of the tall trees, creating patterns of light and shadow on the forest floor. Birds sang cheerfully, and a gentle breeze rustled the branches, making the world feel alive. This serene environment reminded Mia of her childhood, when she spent hours exploring nature's beauty and finding joy in every little detail.
The tranquility of the forest filled her with peace, urging her to reflect on the simple pleasures in life that often go unnoticed.
What central idea is conveyed in this passage?