diff --git a/profile.d/rain.sh b/profile.d/rain.sh
index 86598e0..69d143f 100644
--- a/profile.d/rain.sh
+++ b/profile.d/rain.sh
@@ -42,21 +42,48 @@ _rain_build_colors()
     local base_color="$1"
     RAIN_ENGINE_COLORS=()
 
-    case $base_color in
-        green)
-            for i in {22..28} {34..40} {46..48}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
-        blue)
-            for i in {17..21} {27..33} {39..45}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
-        red)
-            for i in {52..52} {88..88} {124..124} {160..160} {196..201}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
-        yellow)
-            for i in {58..58} {100..100} {142..142} {184..184} {226..229}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
-        cyan)
-            for i in {30..31} {37..38} {44..45} {50..51}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
-        *)
-            RAIN_ENGINE_COLORS=("\e[37m" "\e[37;1m")
-            for i in {244..255}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
-    esac
+    local use_truecolor=0
+    _rainbow_supports_truecolor && use_truecolor=1
+
+    if (( use_truecolor )); then
+        # 24-bit gradient from a near-black shade to a vivid hue.
+        # 20 steps provide smooth depth variation across simultaneous drops.
+        local steps=20
+        local r1 g1 b1 r2 g2 b2
+        case "${base_color}" in
+            green)  r1=0;  g1=12;  b1=2;   r2=50;  g2=255; b2=90  ;;
+            blue)   r1=0;  g1=5;   b1=25;  r2=60;  g2=140; b2=255 ;;
+            red)    r1=15; g1=0;   b1=0;   r2=255; g2=40;  b2=40  ;;
+            yellow) r1=25; g1=18;  b1=0;   r2=255; g2=240; b2=50  ;;
+            cyan)   r1=0;  g1=18;  b1=18;  r2=50;  g2=255; b2=240 ;;
+            *)      r1=40; g1=40;  b1=45;  r2=220; g2=220; b2=255 ;;
+        esac
+
+        local i r g b
+        for ((i = 0; i < steps; i++)); do
+            r=$(( r1 + (r2 - r1) * i / (steps - 1) ))
+            g=$(( g1 + (g2 - g1) * i / (steps - 1) ))
+            b=$(( b1 + (b2 - b1) * i / (steps - 1) ))
+            RAIN_ENGINE_COLORS+=("\e[38;2;${r};${g};${b}m")
+        done
+    else
+        # Fallback: 256-colour palettes.
+        case $base_color in
+            green)
+                for i in {22..28} {34..40} {46..48}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
+            blue)
+                for i in {17..21} {27..33} {39..45}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
+            red)
+                for i in {52..52} {88..88} {124..124} {160..160} {196..201}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
+            yellow)
+                for i in {58..58} {100..100} {142..142} {184..184} {226..229}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
+            cyan)
+                for i in {30..31} {37..38} {44..45} {50..51}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
+            *)
+                RAIN_ENGINE_COLORS=("\e[37m" "\e[37;1m")
+                for i in {244..255}; do RAIN_ENGINE_COLORS+=("\e[38;5;${i}m"); done ;;
+        esac
+    fi
 }
 
 _rain_build_chars()