facelift: fix light-theme scrims/thumbs - :global() the data-theme overrides

Astro scopes compound selectors, so [data-theme=light] .hero__scrim inside a component style
block could never match html[data-theme] - the light theme rendered dark scrims (embossed
low-contrast copy). Wrap the theme prefix in :global() in Hero, ProjectCard and the blog index.
Light 'blueprint' hero now reads clean.

src/components/Hero.astro

@@ -106,7 +106,7 @@ import Constellation from "./Constellation.astro";
       rgba(9, 12, 20, 0.9) 100%
     );
   }
-  [data-theme="light"] .hero__scrim--x {
+  :global([data-theme="light"]) .hero__scrim--x {
     background: linear-gradient(
       90deg,
       rgba(246, 248, 251, 0.96) 0%,
@@ -115,7 +115,7 @@ import Constellation from "./Constellation.astro";
       rgba(246, 248, 251, 0.5) 100%
     );
   }
-  [data-theme="light"] .hero__scrim--y {
+  :global([data-theme="light"]) .hero__scrim--y {
     background: linear-gradient(
       180deg,
       rgba(246, 248, 251, 0.55) 0%,

src/components/ProjectCard.astro

@@ -65,7 +65,7 @@ const dossierNo = String(index).padStart(3, "0");
     position: relative;
     border-bottom: 1px solid rgba(63, 186, 245, 0.12);
   }
-  [data-theme="light"] .dossier__thumb {
+  :global([data-theme="light"]) .dossier__thumb {
     background: var(--surface-2);
     border-bottom-color: var(--border-accent);
   }

src/pages/blog/index.astro

@@ -193,7 +193,7 @@ const featuredSeries = series[featured.id];
     z-index: 1;
     background: linear-gradient(90deg, var(--panel-solid) 0%, transparent 45%);
   }
-  [data-theme="light"] .featured__art::before {
+  :global([data-theme="light"]) .featured__art::before {
     background: linear-gradient(90deg, var(--panel-solid) 0%, transparent 45%);
     opacity: 0.85;
   }