Replace hero mockup with auto-rotating screenshot carousel

- Swap static dashboard card for 3-slide image carousel in hero section
- Slides auto-advance every 4.5s, pause on hover, support manual prev/next and dot navigation
- Add carousel CSS with fade transition, dot indicators, and glow border treatment
- Add carousel JS with goTo/prev/next/auto-rotate logic
- Images expected at img/screenshot-dashboard.png, img/screenshot-cashflow.png, img/screenshot-capital.png

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

styles.css

@@ -623,6 +623,103 @@ body {
   color: var(--gray-700);
 }
 
+/* ---- Screenshot Carousel ---- */
+.screenshot-carousel {
+  width: 100%;
+  max-width: 900px;
+  margin: 60px auto 0;
+  padding: 0 24px;
+}
+.carousel-frame {
+  border-radius: var(--radius-lg);
+  overflow: hidden;
+  border: 1px solid rgba(255,255,255,0.1);
+  box-shadow: 0 0 80px rgba(79,70,229,0.25), var(--shadow-lg);
+  background: var(--gray-800);
+  position: relative;
+}
+.carousel-slides {
+  position: relative;
+  width: 100%;
+}
+.carousel-slide {
+  display: none;
+  flex-direction: column;
+}
+.carousel-slide.active {
+  display: flex;
+}
+.carousel-slide img {
+  width: 100%;
+  height: auto;
+  display: block;
+  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
+}
+.slide-caption {
+  padding: 12px 18px;
+  font-size: 12px;
+  font-weight: 600;
+  color: var(--gray-500);
+  letter-spacing: 0.04em;
+  text-align: center;
+  background: var(--gray-800);
+  border-top: 1px solid rgba(255,255,255,0.06);
+}
+.carousel-controls {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  gap: 16px;
+  margin-top: 18px;
+}
+.carousel-btn {
+  background: rgba(255,255,255,0.06);
+  border: 1px solid rgba(255,255,255,0.1);
+  color: var(--gray-400);
+  width: 36px;
+  height: 36px;
+  border-radius: 50%;
+  cursor: pointer;
+  font-size: 16px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  transition: all 0.15s;
+  flex-shrink: 0;
+}
+.carousel-btn:hover {
+  background: rgba(79,70,229,0.25);
+  border-color: rgba(79,70,229,0.5);
+  color: #fff;
+}
+.carousel-dots {
+  display: flex;
+  gap: 8px;
+  align-items: center;
+}
+.carousel-dot {
+  width: 8px;
+  height: 8px;
+  border-radius: 50%;
+  background: var(--gray-700);
+  cursor: pointer;
+  transition: all 0.2s;
+}
+.carousel-dot.active {
+  background: var(--blue);
+  width: 22px;
+  border-radius: 4px;
+}
+
+/* Fade transition */
+.carousel-slide {
+  opacity: 0;
+  transition: opacity 0.4s ease;
+}
+.carousel-slide.active {
+  opacity: 1;
+}
+
 /* ---- Request Quote pricing ---- */
 .price-amount--quote {
   font-size: 32px;