design: cyan -> rgb(12,96,96) in light theme, #00F0FF stays in dark theme

- globals.css: add --cyan-ai CSS variable (rgb(12,96,96) light / #00F0FF dark)
  + opacity variants --cyan-ai-10/20/30/40/50/80
- Bulk replace all #00F0FF hardcoded Tailwind arbitrary values with
  var(--cyan-ai) / var(--cyan-ai-10) / etc across 55+ TSX/TS files
- Shadow glow colours also updated (suppressed by box-shadow:none in light mode)
- TypeScript: 0 errors

src/app/dashboard/streaks/page.tsx

@@ -1,4 +1,4 @@
-"use client"
+"use client"
 
 import { useState, useEffect } from "react"
 import { Card, CardContent } from "@/components/ui/card"
@@ -49,8 +49,8 @@ export default function StreaksPage() {
       <div className="flex flex-col md:flex-row md:items-end justify-between gap-4">
         <div>
           <h1 className="text-3xl md:text-4xl font-black tracking-tight flex items-center gap-3 mb-1">
-            <span className="p-2.5 rounded-xl bg-yellow-50 dark:bg-[#00F0FF]/10 border border-yellow-300/60 dark:border-[#00F0FF]/20">
-              <Flame className="text-yellow-600 dark:text-[#00F0FF]" size={28} />
+            <span className="p-2.5 rounded-xl bg-yellow-50 dark:bg-[var(--cyan-ai-10)] border border-yellow-300/60 dark:border-[var(--cyan-ai-20)]">
+              <Flame className="text-yellow-600 dark:text-[var(--cyan-ai)]" size={28} />
             </span>
             Your Learning Streak
           </h1>
@@ -88,7 +88,7 @@ export default function StreaksPage() {
                 </div>
                 <div>
                   <p className="text-sm text-muted-foreground mb-1">Total Streak Points Earned</p>
-                  <p className="text-3xl font-bold text-[#00F0FF]">{streakPoints.toLocaleString()}</p>
+                  <p className="text-3xl font-bold text-[var(--cyan-ai)]">{streakPoints.toLocaleString()}</p>
                   {streakPoints === 0 && (
                     <p className="text-xs text-muted-foreground mt-1">Take a test to activate consistency bonus points</p>
                   )}
@@ -106,7 +106,7 @@ export default function StreaksPage() {
       </div>
 
       <div className="pt-8">
-        <h2 className="text-2xl font-bold mb-6 flex items-center gap-2"><Gift className="text-[#00F0FF]" /> Streak Rewards</h2>
+        <h2 className="text-2xl font-bold mb-6 flex items-center gap-2"><Gift className="text-[var(--cyan-ai)]" /> Streak Rewards</h2>
         <div className="space-y-4">
           {rewards.map((reward, i) => (
             <div key={i} className={`p-5 rounded-2xl border flex items-center justify-between transition-colors ${reward.unlocked ? 'bg-primary/5 border-primary/30' : 'bg-secondary/10 border-border opacity-70'}`}>