feat: add rotating background wallpaper

Uses time-bucketed picsum seed (5-min intervals) so all sites
show the same image simultaneously. Sets --bg-url CSS custom
property on body, consumed by .bg-body background-image rule.

1 files changed, 9 insertions, 3 deletions

diff --git a/web/style.css b/web/style.css
index c7e82ae..34395a4 100644
--- a/web/style.css
+++ b/web/style.css
@@ -10,9 +10,9 @@
   --state-budget-exceeded:  #fb923c;
   --state-blocked:          #818cf8;
 
-  --bg:          #0f172a;
-  --surface:     #1e293b;
-  --border:      #334155;
+  --bg:          rgba(15, 23, 42, 0.8);
+  --surface:     rgba(30, 41, 59, 0.75);
+  --border:      rgba(51, 65, 85, 0.7);
   --text:        #e2e8f0;
   --text-muted:  #94a3b8;
   --accent:      #38bdf8;
@@ -32,6 +32,12 @@ body {
   min-height: 100dvh;
 }
 
+body.bg-body {
+  background-image: linear-gradient(rgba(2, 6, 23, 0.65), rgba(2, 6, 23, 0.65)), var(--bg-url, none);
+  background-size: cover;
+  background-position: center;
+}
+
 /* Header */
 header {
   background: var(--surface);