feat: comprehensive light theme support across entire site

- CSS foundation: theme-aware scrollbars, section glows, glass cards with
  gold shadows, stronger animated borders and glow effects for light mode
- Hero: consistent dark-video treatment for both themes, brighter gold
  gradient text, glowing CTA button
- Gradient text: auto-switch to warm gold tones on light backgrounds via
  html:not(.dark) selector
- Team profile: inverted ambient photo bg with white overlay for light,
  dark text/borders, gold-dark labels for contrast
- All sections: text-neutral-500→600 upgrades for WCAG AA contrast,
  gold shadow accents on cards (About, Pricing, FAQ, DayCard, News)
- Admin: replaced hardcoded #c9a96e with theme tokens, fixed select
  options, array editor borders, booking badges contrast
- Header: white text on transparent hero, dark text after scroll
- UI components: BackToTop, FloatingHearts, ShowcaseLayout tabs,
  SignupModal, NewsModal, GroupCard adapted for light backgrounds
- Updated CLAUDE.md to reflect dual theme support

src/components/sections/OpenDay.tsx

@@ -85,8 +85,8 @@ export function OpenDay({ data, popups, teamMembers, locations }: OpenDayProps)
         {/* Pricing info */}
         <Reveal>
           <div className="mt-6 text-center space-y-1">
-            <p className="text-lg font-semibold text-white">
-              {event.pricePerClass} BYN <span className="text-neutral-400 font-normal text-sm">за занятие</span>
+            <p className="text-lg font-semibold text-neutral-900 dark:text-white">
+              {event.pricePerClass} BYN <span className="text-neutral-500 dark:text-neutral-400 font-normal text-sm">за занятие</span>
             </p>
             {event.discountPrice > 0 && event.discountThreshold > 0 && (
               <p className="text-sm text-gold">
@@ -99,7 +99,7 @@ export function OpenDay({ data, popups, teamMembers, locations }: OpenDayProps)
 
         {event.description && (
           <Reveal>
-            <div className="mt-4 text-center text-sm text-neutral-400 max-w-2xl mx-auto">
+            <div className="mt-4 text-center text-sm text-neutral-500 dark:text-neutral-400 max-w-2xl mx-auto">
               {formatMarkup(event.description)}
             </div>
           </Reveal>
@@ -112,7 +112,7 @@ export function OpenDay({ data, popups, teamMembers, locations }: OpenDayProps)
             <Reveal>
               <div className="max-w-lg mx-auto space-y-3">
                 <div className="text-center mb-4">
-                  <h3 className="text-base font-semibold text-white">{halls[0]}</h3>
+                  <h3 className="text-base font-semibold text-neutral-900 dark:text-white">{halls[0]}</h3>
                   {hallAddress[halls[0]] && (
                     <p className="text-sm text-gold/70 mt-0.5 flex items-center justify-center gap-1.5">
                       <MapPin size={13} />
@@ -137,8 +137,8 @@ export function OpenDay({ data, popups, teamMembers, locations }: OpenDayProps)
               {halls.map((hall) => (
                 <Reveal key={hall}>
                   <div>
-                    <div className="text-center mb-4 rounded-lg bg-white/[0.03] border border-white/[0.06] py-3 px-4">
-                      <h3 className="text-base font-semibold text-white">{hall}</h3>
+                    <div className="text-center mb-4 rounded-lg bg-neutral-50 border border-neutral-200 py-3 px-4 dark:bg-white/[0.03] dark:border-white/[0.06]">
+                      <h3 className="text-base font-semibold text-neutral-900 dark:text-white">{hall}</h3>
                       {hallAddress[hall] && (
                         <p className="text-sm text-gold/70 mt-0.5 flex items-center justify-center gap-1.5">
                           <MapPin size={13} />
@@ -196,15 +196,15 @@ function ClassCard({
 
   if (cls.cancelled) {
     return (
-      <div className="rounded-xl border border-white/[0.06] bg-white/[0.02] p-3 sm:p-4 opacity-50">
+      <div className="rounded-xl border border-neutral-200 bg-neutral-50 p-3 sm:p-4 opacity-50 dark:border-white/[0.06] dark:bg-white/[0.02]">
         <div className="flex items-center justify-between gap-3">
           <div className="flex-1 min-w-0 space-y-1">
-            <span className="rounded-md bg-neutral-800 px-2 py-0.5 text-xs font-bold text-neutral-500">
+            <span className="rounded-md bg-neutral-200 px-2 py-0.5 text-xs font-bold text-neutral-500 dark:bg-neutral-800">
               <time dateTime={`${cls.startTime}-${cls.endTime}`}>{cls.startTime}–{cls.endTime}</time>
             </span>
             <p className="text-sm text-neutral-500"><del>{cls.trainer} · {cls.style}</del></p>
           </div>
-          <span className="text-xs text-neutral-500 bg-neutral-800 rounded-full px-2.5 py-0.5 font-medium">
+          <span className="text-xs text-neutral-500 bg-neutral-200 rounded-full px-2.5 py-0.5 font-medium dark:bg-neutral-800">
             Отменено
           </span>
         </div>
@@ -217,8 +217,8 @@ function ClassCard({
   return (
     <div className={`rounded-xl border transition-all ${
       isFull
-        ? "border-white/[0.04] bg-white/[0.01]"
-        : "border-white/[0.06] bg-white/[0.02] hover:border-white/[0.12] hover:bg-white/[0.04]"
+        ? "border-neutral-200 bg-neutral-50/50 dark:border-white/[0.04] dark:bg-white/[0.01]"
+        : "border-neutral-200 bg-white hover:border-neutral-300 hover:bg-neutral-50 dark:border-white/[0.06] dark:bg-white/[0.02] dark:hover:border-white/[0.12] dark:hover:bg-white/[0.04]"
     }`}>
       <div className="flex items-start gap-3 p-3 sm:p-4">
         {/* Trainer photo */}
@@ -227,14 +227,14 @@ function ClassCard({
             window.dispatchEvent(new CustomEvent("openTrainerProfile", { detail: cls.trainer }));
           }}
           aria-label={`Профиль тренера: ${cls.trainer}`}
-          className="relative flex items-center justify-center h-11 w-11 rounded-full overflow-hidden shrink-0 ring-1 ring-white/10 hover:ring-gold/30 transition-all cursor-pointer mt-0.5"
+          className="relative flex items-center justify-center h-11 w-11 rounded-full overflow-hidden shrink-0 ring-1 ring-neutral-200 hover:ring-gold/30 transition-all cursor-pointer mt-0.5 dark:ring-white/10"
           title={`Подробнее о ${cls.trainer}`}
         >
           {trainerPhoto ? (
             <Image src={trainerPhoto} alt={cls.trainer} fill className="object-cover" sizes="44px" />
           ) : (
-            <div className="flex items-center justify-center h-full w-full bg-white/[0.06]">
-              <User size={16} className="text-white/40" />
+            <div className="flex items-center justify-center h-full w-full bg-neutral-100 dark:bg-white/[0.06]">
+              <User size={16} className="text-neutral-400 dark:text-white/40" />
             </div>
           )}
         </button>
@@ -245,7 +245,7 @@ function ClassCard({
             onClick={() => {
               window.dispatchEvent(new CustomEvent("openTrainerProfile", { detail: cls.trainer }));
             }}
-            className="text-sm font-semibold text-white/90 hover:text-gold transition-colors cursor-pointer"
+            className="text-sm font-semibold text-neutral-900 hover:text-gold transition-colors cursor-pointer dark:text-white/90"
           >
             {cls.trainer}
           </button>
@@ -256,7 +256,7 @@ function ClassCard({
               <span className="rounded-md bg-gold/10 px-2 py-0.5 text-xs font-bold text-gold min-w-[80px] text-center">
                 <time dateTime={`${cls.startTime}-${cls.endTime}`}>{cls.startTime}–{cls.endTime}</time>
               </span>
-              <span className="text-sm font-medium text-white/60">{cls.style}</span>
+              <span className="text-sm font-medium text-neutral-500 dark:text-white/60">{cls.style}</span>
             </div>
           </div>
 
@@ -265,8 +265,8 @@ function ClassCard({
             {maxParticipants > 0 && (
               <span className={`rounded-full px-2.5 py-0.5 text-xs font-semibold ${
                 isFull
-                  ? "bg-amber-500/15 border border-amber-500/25 text-amber-400"
-                  : "bg-white/[0.04] border border-white/[0.08] text-white/45"
+                  ? "bg-amber-500/15 border border-amber-500/25 text-amber-500 dark:text-amber-400"
+                  : "bg-neutral-100 border border-neutral-200 text-neutral-600 dark:bg-white/[0.04] dark:border-white/[0.08] dark:text-white/45"
               }`}>
                 {cls.bookingCount}/{maxParticipants} мест
               </span>
@@ -280,7 +280,7 @@ function ClassCard({
           className={`shrink-0 self-center rounded-xl px-4 py-2.5 text-xs font-semibold transition-all cursor-pointer ${
             isFull
               ? "bg-amber-500/10 border border-amber-500/25 text-amber-400 hover:bg-amber-500/20 hover:border-amber-500/40"
-              : "bg-gold/10 border border-gold/25 text-gold hover:bg-gold/20 hover:border-gold/40"
+              : "bg-gold/10 border border-gold/25 text-gold hover:bg-gold/20 hover:border-gold/40 dark:bg-gold/5 dark:border-gold/15"
           }`}
         >
           {isFull ? "Лист ожидания" : "Записаться"}