This example shows an animated SVG sunrise and sunset over a layered mountain landscape. The sky is a radial gradient that gradually shifts from aliceblue to indigo, while the sun moves along a vertical path from its center position downward. Three different gradient fills create depth across two landscape paths. The animation is driven by SMIL `<animate>` elements on the SVG attributes, with a 15-second cycle that repeats indefinitely. The visual demonstrates pure SVG fundamentals without external libraries.