polish: improve atmosphere effects and fix fog opacity jump

- Fire: reworked colour ramp (dark red → orange → amber → warm yellow core),
  per-column height variation via colFireH for jagged silhouette, ember glow
  at base, taller overall height, fire/rain combined in screenshot
- Rain: more translucent (0.15–0.40 opacity), halved speed range, direction
  tilts 90°→70° as intensity rises
- Embers: smaller particles (0.8–2.2px), more numerous (50–150)
- Fog: fix opacity jump at ~3s — CSS keyframe animation was overriding the
  inline intensity-based opacity value; replaced with CSS transition via
  React-managed mounted state

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/src/components/FogOverlay.module.css

@@ -4,19 +4,9 @@
   z-index: 9998;
   pointer-events: none;
   overflow: hidden;
-  animation: fadeIn 3s ease-in;
   filter: var(--fog-filter);
 }
 
-@keyframes fadeIn {
-  from {
-    opacity: 0;
-  }
-  to {
-    opacity: 1;
-  }
-}
-
 .layer1,
 .layer2,
 .layer3 {

client/src/components/FogOverlay.tsx

@@ -1,3 +1,4 @@
+import { useEffect, useState } from "react";
 import styles from "./FogOverlay.module.css";
 
 interface FogOverlayProps {
@@ -6,13 +7,23 @@ interface FogOverlayProps {
 }
 
 export default function FogOverlay({ active, intensity }: FogOverlayProps) {
+  // One-frame delay lets the browser paint opacity:0 first so the CSS transition fires.
+  // Without this the element mounts at full opacity with no fade-in.
+  const [visible, setVisible] = useState(false);
+
+  useEffect(() => {
+    if (!active) { setVisible(false); return; }
+    const id = requestAnimationFrame(() => setVisible(true));
+    return () => cancelAnimationFrame(id);
+  }, [active]);
+
   if (!active) return null;
 
   // Map 0–100 to 0.15–1.0 so fog is always at least faintly visible when active
-  const opacity = 0.15 + (intensity / 100) * 0.85;
+  const opacity = visible ? 0.15 + (intensity / 100) * 0.85 : 0;
 
   return (
-    <div className={styles.overlay} style={{ opacity }}>
+    <div className={styles.overlay} style={{ opacity, transition: "opacity 3s ease-in" }}>
       <div className={styles.layer1} />
       <div className={styles.layer2} />
       <div className={styles.layer3} />

client/src/components/ThreeFireOverlay.tsx

@@ -43,14 +43,14 @@ const FRAG = /* glsl */ `
     return v / 0.9375;
   }
 
-  // Fire colour ramp: black → dark red → orange → yellow → pale yellow
+  // Fire colour ramp: black → deep red tips → orange → amber → warm yellow core
   vec3 fireRamp(float t) {
     t = clamp(t, 0.0, 1.0);
-    vec3 c0 = vec3(0.00, 0.00, 0.00);
-    vec3 c1 = vec3(0.65, 0.04, 0.00);
-    vec3 c2 = vec3(1.00, 0.28, 0.00);
-    vec3 c3 = vec3(1.00, 0.76, 0.05);
-    vec3 c4 = vec3(1.00, 1.00, 0.55);
+    vec3 c0 = vec3(0.00, 0.00, 0.00); // black / transparent
+    vec3 c1 = vec3(0.68, 0.05, 0.00); // deep red (cool tips)
+    vec3 c2 = vec3(1.00, 0.32, 0.00); // rich orange (mid flame)
+    vec3 c3 = vec3(1.00, 0.56, 0.02); // amber-orange (inner flame)
+    vec3 c4 = vec3(1.00, 0.84, 0.28); // warm yellow (dense core, not pure white)
     if (t < 0.25) return mix(c0, c1, t * 4.0);
     if (t < 0.50) return mix(c1, c2, (t - 0.25) * 4.0);
     if (t < 0.75) return mix(c2, c3, (t - 0.50) * 4.0);
@@ -58,19 +58,25 @@ const FRAG = /* glsl */ `
   }
 
   void main() {
-    // How tall the fire reaches (fraction of screen height)
-    float fireH = 0.28 + uIntensity * 0.24; // 0.28–0.52
-
-    // Normalised height inside fire zone (0=ground, 1=top of flames)
-    float yN = vUv.y / fireH;
-
-    // Discard pixels comfortably above the fire zone
-    if (yN > 1.6) { gl_FragColor = vec4(0.0); return; }
-
     float t = uTime * 0.45;
 
-    // Noise coords: aspect-corrected X, upward-scrolling Y
-    vec2 p = vec2(vUv.x * uAspect * 1.6, vUv.y / fireH * 1.4 - t);
+    // Base fire height (fraction of screen height) — taller overall
+    float fireH = 0.42 + uIntensity * 0.28; // 0.42–0.70
+
+    // Per-column height variation: slow wide FBM humps create distinct tall/short columns.
+    // Varying colFireH changes where yN=1 lands on screen, so the early discard below
+    // produces a naturally jagged silhouette rather than a flat top.
+    float heightVar = 0.52 * fbm(vec2(vUv.x * uAspect * 1.1 + t * 0.07, t * 0.05));
+    float colFireH  = fireH * (1.0 + heightVar); // per-column effective height
+
+    // Normalised height inside this column's fire zone (0=ground, 1=column top)
+    float yN = vUv.y / colFireH;
+
+    // Discard pixels above the fire zone — jagged because colFireH varies per column
+    if (yN > 1.6) { gl_FragColor = vec4(0.0); return; }
+
+    // Noise coords: aspect-corrected X, upward-scrolling Y scaled to column height
+    vec2 p = vec2(vUv.x * uAspect * 1.6, vUv.y / colFireH * 1.4 - t);
 
     // Layered FBM — coarse structure + fine flicker
     float n  = fbm(p * 1.8);
@@ -78,12 +84,12 @@ const FRAG = /* glsl */ `
     n += 0.20 * fbm(p * 7.0 - vec2(0.0, t * 0.6));
     n /= 1.75;
 
-    // Vary flame height horizontally for ragged top edge
-    float crest = 0.25 * noise(vec2(vUv.x * uAspect * 2.0 + t * 0.18, 0.3));
+    // Fine ragged tips on top of the broad column silhouette
+    float crest = 0.16 * noise(vec2(vUv.x * uAspect * 4.0 + t * 0.22, 1.1));
     float yMod  = yN + crest;
 
-    // Core fire value
-    float fire = (1.0 - yMod) * 1.1 + n * 0.75 - 0.05;
+    // Core fire value — 0.88 lets noise breathe at ground level
+    float fire = (1.0 - yMod) * 0.88 + n * 0.92 - 0.05;
     fire *= 1.0 + uIntensity * 0.35;
     fire = clamp(fire, 0.0, 1.0);
 
@@ -92,7 +98,10 @@ const FRAG = /* glsl */ `
     fire *= 0.72 + edge * 0.28;
 
     vec3  col   = fireRamp(fire);
-    float alpha = fire * fire; // quadratic → softer halo falloff
+    // Deep red/ember tint near the base — coals and heat where flame meets ground
+    float emberBase = smoothstep(0.30, 0.0, yN);
+    col = mix(col, vec3(0.70, 0.08, 0.00), emberBase * 0.45);
+    float alpha = pow(fire, 1.6);
 
     gl_FragColor = vec4(col * alpha, alpha);
   }

client/src/lib/particleConfigs.ts

@@ -1,25 +1,26 @@
 import type { ISourceOptions } from "@tsparticles/engine";
 
 /**
- * Rain — intensity 0–100 → count 200–600, speed 15–30
- * Fast-falling blue-white circles. At this speed the motion itself
- * reads as rain streaks — no elongated shape needed.
+ * Rain — intensity 0–100 → count 200–600, speed 15–22.5
+ * More translucent, half speed range, direction tilts from 90° (vertical)
+ * to 70° (wind-driven) as intensity rises. In tsparticles degrees: 90=down, 70=bottom-right lean.
  */
 export function getRainConfig(intensity: number): ISourceOptions {
   const count = Math.round(200 + (intensity / 100) * 400);
-  const speed = 15 + (intensity / 100) * 15;
+  const speed = 15 + (intensity / 100) * 7.5;          // half the previous speed range
+  const direction = 90 - (intensity / 100) * 20;        // 90° straight down → 70° angled
   return {
     fullScreen: { enable: true, zIndex: 9997 },
     particles: {
       number: { value: count, density: { enable: false } },
       color: { value: "#aad4f5" },
       shape: { type: "circle" },
-      opacity: { value: { min: 0.4, max: 0.75 } },
+      opacity: { value: { min: 0.15, max: 0.40 } },
       size: { value: { min: 1, max: 2.5 } },
       move: {
         enable: true,
         speed: speed,
-        direction: "bottom",
+        direction: direction as never,
         straight: true,
         outModes: { default: "out" },
       },
@@ -29,12 +30,11 @@ export function getRainConfig(intensity: number): ISourceOptions {
 }
 
 /**
- * Embers — intensity 0–100 → count 20–80, speed 0.5–2
- * Slow-drifting warm amber dots with flickering opacity.
- * Clearly slower and dimmer than fire — different mood entirely.
+ * Embers — intensity 0–100 → count 50–150, speed 0.5–2
+ * Smaller, more numerous slow-drifting sparks. Flickering opacity.
  */
 export function getEmbersConfig(intensity: number): ISourceOptions {
-  const count = Math.round(20 + (intensity / 100) * 60);
+  const count = Math.round(50 + (intensity / 100) * 100);
   const speed = 0.5 + (intensity / 100) * 1.5;
   return {
     fullScreen: { enable: true, zIndex: 9997 },
@@ -46,7 +46,7 @@ export function getEmbersConfig(intensity: number): ISourceOptions {
         value: { min: 0.15, max: 0.9 },
         animation: { enable: true, speed: 0.6, sync: false, startValue: "random" },
       },
-      size: { value: { min: 1.5, max: 4 } },
+      size: { value: { min: 0.8, max: 2.2 } },
       move: {
         enable: true,
         speed: speed,

site/screenshots.js

@@ -198,13 +198,25 @@ async function captureAtmosphere(page) {
   await page.click('button[title="Atmosphere effects"]');
   await page.waitForTimeout(300);
 
-  // Toggle Fog on — the toggle button has aria-label="Toggle Fog"
+  // Toggle Fog on
   await page.click('button[aria-label="Toggle Fog"]');
-  await page.waitForTimeout(800); // wait for fog to render
-  // Screenshot captures fog effect over the campaign view
+  await page.waitForTimeout(400);
 
-  // Close the atmosphere panel after so it doesn't clutter other captures
-  await page.keyboard.press('Escape');
+  // Toggle Fire on and set intensity to 25%
+  // Effects order: fog(0), fire(1), rain(2), embers(3) — fire is 2nd slider
+  await page.click('button[aria-label="Toggle Fire"]');
+  await page.waitForTimeout(300);
+  await page.evaluate(() => {
+    const sliders = document.querySelectorAll('input[type="range"]');
+    const fireSlider = sliders[1];
+    fireSlider.value = '25';
+    fireSlider.dispatchEvent(new Event('input', { bubbles: true }));
+    fireSlider.dispatchEvent(new MouseEvent('mouseup', { bubbles: true }));
+  });
+  await page.waitForTimeout(1200); // wait for both effects to render
+
+  // Close the atmosphere panel so it doesn't clutter the screenshot
+  await page.click('button[title="Atmosphere effects"]');
   await page.waitForTimeout(200);
 }