Cyberpunk visual overhaul

Dark CARTO basemap (was default bright OSM tiles), Orbitron/Share Tech
Mono fonts, neon cyan/magenta HUD chrome with glassmorphism panels,
glowing divIcon portal markers (pulsing when claimed) replacing plain
circle dots, neon drop-shadow filters on links/fields, and a subtle
scanline overlay. Login and team-pick screens restyled to match.

frontend/src/style.css

@@ -6,3 +6,80 @@ html, body, #app {
   height: 100%;
   margin: 0;
 }
+
+body {
+  background: #050508;
+  color: #d8fbff;
+  font-family: 'Share Tech Mono', monospace;
+}
+
+h1, h2, .font-display {
+  font-family: 'Orbitron', sans-serif;
+}
+
+/* Subtle animated scanline field over the whole app — cheap, pure-CSS. */
+#app::before {
+  content: '';
+  position: fixed;
+  inset: 0;
+  pointer-events: none;
+  z-index: 2000;
+  background-image: repeating-linear-gradient(
+    0deg,
+    rgba(0, 255, 242, 0.035) 0px,
+    rgba(0, 255, 242, 0.035) 1px,
+    transparent 1px,
+    transparent 3px
+  );
+  mix-blend-mode: screen;
+}
+
+.text-glow-cyan { text-shadow: 0 0 8px rgba(0, 255, 242, 0.85); }
+.text-glow-orange { text-shadow: 0 0 8px rgba(255, 95, 31, 0.9); }
+.text-glow-green { text-shadow: 0 0 8px rgba(57, 255, 20, 0.9); }
+
+.hud-panel {
+  background: rgba(8, 10, 20, 0.88);
+  backdrop-filter: blur(10px);
+  border: 1px solid rgba(0, 255, 242, 0.35);
+  box-shadow: 0 0 20px rgba(0, 255, 242, 0.12), inset 0 0 30px rgba(0, 255, 242, 0.04);
+  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
+}
+
+/* Darken + tint the CARTO dark tiles a bit further and desaturate slightly
+   so our neon markers/links pop harder against the basemap. */
+.leaflet-tile-pane {
+  filter: brightness(0.75) saturate(1.3) hue-rotate(-6deg);
+}
+
+.leaflet-container {
+  background: #050508 !important;
+}
+
+.leaflet-popup-content-wrapper,
+.leaflet-tooltip {
+  background: rgba(8, 10, 20, 0.92) !important;
+  color: #d8fbff !important;
+  border: 1px solid rgba(0, 255, 242, 0.4) !important;
+  font-family: 'Share Tech Mono', monospace !important;
+  box-shadow: 0 0 12px rgba(0, 255, 242, 0.25) !important;
+}
+.leaflet-popup-tip {
+  background: rgba(8, 10, 20, 0.92) !important;
+}
+
+.regress-portal-marker {
+  filter: drop-shadow(0 0 4px var(--portal-glow, #9ca3af));
+}
+.regress-portal-marker.claimed {
+  animation: portal-pulse 2.4s ease-in-out infinite;
+}
+@keyframes portal-pulse {
+  0%, 100% { filter: drop-shadow(0 0 4px var(--portal-glow, #9ca3af)); }
+  50% { filter: drop-shadow(0 0 10px var(--portal-glow, #9ca3af)); }
+}
+
+.regress-link-orange { filter: drop-shadow(0 0 4px #ff5f1f); }
+.regress-link-green { filter: drop-shadow(0 0 4px #39ff14); }
+.regress-field-orange { filter: drop-shadow(0 0 6px #ff5f1f); }
+.regress-field-green { filter: drop-shadow(0 0 6px #39ff14); }