Option 1 · TactileStyle: light-modelled skeuomorphism (accent) · Components: four-shadow pill, arrow disc · Art: none · Motion: press 0.97 + inset flip, disc turns 45° · Material: tactile 4-shadow
gradient fill → deep stop · 4 box-shadows · pressed inset swapped as a state

Option 2 · Frosted glass barStyle: glass control layer over media · Components: sticky Book bar, solid pill · Art: the real Aura room · Motion: press 0.97, halo on press · Material: frosted glass (bar only)
backdrop-filter: blur(var(--glass-blur)) saturate() over an 80 % surface tint · @supports fallback to solid

Option 3 · Liquid glassStyle: liquid glass on the control (A5) · Components: translucent capsule, specular rim, caustic glow · Art: aurora light pool behind · Motion: press 0.97, glow brightens · Material: frost + faked refraction
layered gradients + inset rims + backdrop blur; no SVG displacement, so iPhone sees the same

Option 4 · Light-upStyle: flat · monochrome + one accent · Components: solid pill, hex tap ripple · Art: none · Motion: one shimmer sweep, ripple, inner light on press · Material: flat / solid
Magic UI shimmer-button re-made in CSS · lab.js hex ripple · inset glow + halo ring on press

Option 5 · Grainy fieldStyle: grainy gradient (A8), one hue · Components: card footer field, near-black pay pill · Art: 5 % static grain · Motion: press 0.97, blue halo on press · Material: flat + grain
feTurbulence data-URI grain (--grain) over a one-hue gradient · hierarchy by fill (Ink on light, White on dark)