feat(lessons): add lessons from client db

src/pages/student/lessons/ProportionalLesson.tsx

@@ -0,0 +1,480 @@
+import React, { useRef, useState, useEffect } from "react";
+import {
+  ArrowDown,
+  Check,
+  BookOpen,
+  Scale,
+  Calculator,
+  ArrowLeftRight,
+  Percent,
+} from "lucide-react";
+import RatioVisualizerWidget from "../../../components/lessons/RatioVisualizerWidget";
+import UnitConversionWidget from "../../../components/lessons/UnitConversionWidget";
+import PercentChangeWidget from "../../../components/lessons/PercentChangeWidget";
+import MultiStepPercentWidget from "../../../components/lessons/MultiStepPercentWidget";
+import Quiz from "../../../components/lessons/Quiz";
+import {
+  PROPORTIONAL_QUIZ_DATA,
+  PERCENTAGES_ADV_QUIZ,
+  PERCENTAGES_QUIZ_DATA,
+} from "../../../utils/constants";
+import { Frac } from "../../../components/Math";
+
+interface LessonProps {
+  onFinish?: () => void;
+}
+
+const ProportionalLesson: React.FC<LessonProps> = ({ onFinish }) => {
+  const [activeSection, setActiveSection] = useState(0);
+  const sectionsRef = useRef<(HTMLElement | null)[]>([]);
+
+  const scrollToSection = (index: number) => {
+    setActiveSection(index);
+    sectionsRef.current[index]?.scrollIntoView({
+      behavior: "smooth",
+      block: "start",
+    });
+  };
+
+  useEffect(() => {
+    const observer = new IntersectionObserver(
+      (entries) => {
+        entries.forEach((entry) => {
+          if (entry.isIntersecting) {
+            const index = sectionsRef.current.indexOf(
+              entry.target as HTMLElement,
+            );
+            if (index !== -1) {
+              setActiveSection(index);
+            }
+          }
+        });
+      },
+      { rootMargin: "-20% 0px -60% 0px" },
+    );
+
+    sectionsRef.current.forEach((section) => {
+      if (section) observer.observe(section);
+    });
+    return () => observer.disconnect();
+  }, []);
+
+  const SectionMarker = ({
+    index,
+    title,
+    icon: Icon,
+  }: {
+    index: number;
+    title: string;
+    icon: any;
+  }) => {
+    const isActive = activeSection === index;
+    const isPast = activeSection > index;
+    return (
+      <button
+        onClick={() => scrollToSection(index)}
+        className={`flex items-center gap-3 p-3 w-full rounded-lg transition-all ${isActive ? "bg-white shadow-md border border-amber-100" : "hover:bg-slate-100"}`}
+      >
+        <div
+          className={`w-8 h-8 rounded-full flex items-center justify-center shrink-0 ${isActive ? "bg-amber-600 text-white" : isPast ? "bg-amber-400 text-white" : "bg-slate-200 text-slate-500"}`}
+        >
+          {isPast ? (
+            <Check className="w-4 h-4" />
+          ) : (
+            <Icon className="w-4 h-4" />
+          )}
+        </div>
+        <div className="text-left">
+          <p
+            className={`text-sm font-bold ${isActive ? "text-amber-900" : "text-slate-600"}`}
+          >
+            {title}
+          </p>
+        </div>
+      </button>
+    );
+  };
+
+  const allQuizzes = [
+    ...PROPORTIONAL_QUIZ_DATA,
+    ...PERCENTAGES_ADV_QUIZ,
+    ...PERCENTAGES_QUIZ_DATA,
+  ];
+
+  return (
+    <div className="flex flex-col lg:flex-row min-h-screen">
+      <aside className="w-full lg:w-64 lg:fixed lg:top-20 lg:bottom-0 lg:overflow-y-auto p-4 border-r border-slate-200 bg-slate-50 z-0 hidden lg:block">
+        <nav className="space-y-2">
+          <SectionMarker index={0} title="Ratios" icon={Scale} />
+          <SectionMarker
+            index={1}
+            title="Unit Conversions"
+            icon={ArrowLeftRight}
+          />
+          <SectionMarker index={2} title="Percent Changes" icon={Percent} />
+          <SectionMarker
+            index={3}
+            title="Multi-Step & Interest"
+            icon={Calculator}
+          />
+          <SectionMarker index={4} title="Practice" icon={BookOpen} />
+        </nav>
+      </aside>
+
+      <div className="flex-1 lg:ml-64 p-6 md:p-12 max-w-4xl mx-auto">
+        {/* Section 1: Ratios */}
+        <section
+          ref={(el) => {
+            sectionsRef.current[0] = el;
+          }}
+          className="min-h-screen flex flex-col justify-center mb-24 pt-20 lg:pt-0"
+        >
+          <h2 className="text-4xl font-extrabold text-slate-900 mb-6">
+            Ratios & Proportions
+          </h2>
+          <div className="prose prose-slate text-lg text-slate-600 mb-8">
+            <p>
+              A <strong>Ratio</strong> compares two quantities. A critical SAT
+              skill is distinguishing between <strong>Part-to-Part</strong> and{" "}
+              <strong>Part-to-Whole</strong> ratios, and knowing which one a
+              question is asking for.
+            </p>
+            <div className="grid md:grid-cols-2 gap-4 mt-4">
+              <div className="bg-amber-50 border border-amber-200 rounded-xl p-5">
+                <p className="font-bold text-amber-900 mb-2">Part-to-Part</p>
+                <p className="text-sm text-slate-700 mb-2">
+                  Compares one part of a whole to another part. Neither number
+                  is the total.
+                </p>
+                <div className="font-mono text-center bg-white py-1 rounded text-amber-700 text-sm">
+                  Boys : Girls = 3 : 2
+                </div>
+                <p className="text-xs text-slate-500 mt-2">
+                  Means: for every 3 boys there are 2 girls. Total parts = 5.
+                </p>
+              </div>
+              <div className="bg-amber-50 border border-amber-200 rounded-xl p-5">
+                <p className="font-bold text-amber-900 mb-2">Part-to-Whole</p>
+                <p className="text-sm text-slate-700 mb-2">
+                  Compares one part to the total. This is equivalent to a
+                  fraction or percentage.
+                </p>
+                <div className="font-mono text-center bg-white py-1 rounded text-amber-700 text-sm">
+                  Boys : Total = 3 : 5
+                </div>
+                <p className="text-xs text-slate-500 mt-2">
+                  Means: boys make up 3 out of 5 = 60% of the total group.
+                </p>
+              </div>
+            </div>
+            <div className="mt-4 bg-slate-100 p-4 rounded-xl border-l-4 border-amber-500 text-sm">
+              <p className="font-bold text-amber-900 mb-1">
+                Cross-Multiplication for Proportions
+              </p>
+              <p className="text-slate-700 mb-2">
+                When two ratios are equal (a proportion), cross-multiply to
+                solve for an unknown:
+              </p>
+              <div className="font-mono text-center bg-white py-2 rounded text-slate-700 font-bold mb-1">
+                <Frac n="a" d="b" /> = <Frac n="c" d="d" /> → a × d = b × c
+              </div>
+              <p className="text-xs text-slate-500">
+                Example: <Frac n="3" d="4" /> = <Frac n="x" d="20" /> → 3 × 20 =
+                4 × x → 60 = 4x → x = <strong>15</strong>
+              </p>
+            </div>
+            <div className="mt-4 bg-amber-50 border border-amber-200 rounded-xl p-4 text-sm">
+              <p className="font-bold text-amber-900 mb-1">
+                The k-Multiplier Method
+              </p>
+              <p className="text-slate-700">
+                If a ratio is a : b, the actual amounts are <strong>ak</strong>{" "}
+                and <strong>bk</strong> for some positive number k. Use this
+                when you know the ratio and the total.
+              </p>
+              <div className="font-mono text-center bg-white py-1 rounded text-amber-700 text-sm mt-2">
+                Ratio 3:2, Total = 25 → 3k + 2k = 25 → k = 5 → Parts: 15 and 10
+              </div>
+            </div>
+            <p className="text-base text-slate-600 mt-4">
+              Use the tool below to see how scaling a ratio (multiplying by{" "}
+              <em>k</em>) keeps the proportions the same.
+            </p>
+          </div>
+          <RatioVisualizerWidget />
+          <button
+            onClick={() => scrollToSection(1)}
+            className="mt-12 group flex items-center text-amber-600 font-bold hover:text-amber-800 transition-colors"
+          >
+            Next: Unit Conversions{" "}
+            <ArrowDown className="ml-2 w-5 h-5 group-hover:translate-y-1 transition-transform" />
+          </button>
+        </section>
+
+        {/* Section 2: Unit Conversions */}
+        <section
+          ref={(el) => {
+            sectionsRef.current[1] = el;
+          }}
+          className="min-h-screen flex flex-col justify-center mb-24"
+        >
+          <h2 className="text-4xl font-extrabold text-slate-900 mb-6">
+            Dimensional Analysis
+          </h2>
+          <div className="prose prose-slate text-lg text-slate-600 mb-8">
+            <p>
+              To convert units, multiply by conversion fractions equal to 1
+              (like <strong>5280 ft per mile</strong>). Arrange the fractions so
+              the units you <em>don't</em> want cancel out (top and bottom).
+            </p>
+            <div className="mt-4 bg-amber-50 border border-amber-200 rounded-xl p-5">
+              <p className="font-bold text-amber-900 mb-2">
+                Step-by-Step Chain Multiplication
+              </p>
+              <ol className="list-decimal list-inside space-y-1 text-sm text-slate-700">
+                <li>
+                  Write the starting value as a fraction (e.g., 60 miles / 1
+                  hour).
+                </li>
+                <li>
+                  Multiply by a conversion fraction that cancels the unit you
+                  want to remove.
+                </li>
+                <li>Repeat until only the desired units remain.</li>
+                <li>
+                  Multiply all numerators, multiply all denominators, then
+                  divide.
+                </li>
+              </ol>
+            </div>
+            <div className="mt-4 bg-slate-100 p-4 rounded-xl border-l-4 border-amber-500 text-sm">
+              <p className="font-bold text-amber-900 mb-2">
+                Worked Example: Convert 60 miles/hour to feet/second
+              </p>
+              <div className="font-mono text-slate-700 space-y-2 text-xs">
+                <div className="bg-white rounded p-2">
+                  <span className="text-amber-700 font-bold">Step 1:</span>{" "}
+                  Start with 60 miles/hr
+                </div>
+                <div className="bg-white rounded p-2">
+                  <span className="text-amber-700 font-bold">Step 2:</span> ×
+                  (5280 ft / 1 mile) ← cancels "miles"
+                </div>
+                <div className="bg-white rounded p-2">
+                  <span className="text-amber-700 font-bold">Step 3:</span> × (1
+                  hr / 3600 sec) ← cancels "hours"
+                </div>
+                <div className="bg-white rounded p-3 border-2 border-amber-300">
+                  <span className="text-amber-700 font-bold">Result:</span>{" "}
+                  <Frac n="60 × 5280" d="1 × 3600" /> ={" "}
+                  <Frac n="316,800" d="3600" /> ={" "}
+                  <strong className="text-amber-800">88 feet per second</strong>
+                </div>
+              </div>
+              <p className="text-xs text-slate-500 mt-2">
+                Notice how miles and hours both cancel, leaving only feet/second
+                — exactly what was asked for.
+              </p>
+            </div>
+          </div>
+          <UnitConversionWidget />
+          <button
+            onClick={() => scrollToSection(2)}
+            className="mt-12 group flex items-center text-amber-600 font-bold hover:text-amber-800 transition-colors"
+          >
+            Next: Percent Changes{" "}
+            <ArrowDown className="ml-2 w-5 h-5 group-hover:translate-y-1 transition-transform" />
+          </button>
+        </section>
+
+        {/* Section 3: Percent Increases & Decreases */}
+        <section
+          ref={(el) => {
+            sectionsRef.current[2] = el;
+          }}
+          className="min-h-screen flex flex-col justify-center mb-24"
+        >
+          <h2 className="text-4xl font-extrabold text-slate-900 mb-6">
+            Percent Increases & Decreases
+          </h2>
+          <div className="prose prose-slate text-lg text-slate-600 mb-8">
+            <p>
+              The most important SAT skill for percentages is using{" "}
+              <strong>multipliers</strong> — a single number that captures both
+              the original value and the change.
+            </p>
+            <div className="grid md:grid-cols-2 gap-4 mt-4">
+              <div className="bg-amber-50 border border-amber-200 rounded-xl p-5">
+                <p className="font-bold text-amber-900 mb-2">
+                  Percent Increase
+                </p>
+                <div className="font-mono text-center bg-white py-2 rounded text-amber-700 font-bold mb-2">
+                  New = Original × (1 + r)
+                </div>
+                <p className="text-xs text-slate-600">
+                  Where r is the rate as a decimal (e.g., 30% → r = 0.30)
+                </p>
+                <p className="text-xs text-slate-500 mt-1">
+                  Example: $200 increased by 15% → 200 × 1.15 ={" "}
+                  <strong>$230</strong>
+                </p>
+              </div>
+              <div className="bg-amber-50 border border-amber-200 rounded-xl p-5">
+                <p className="font-bold text-amber-900 mb-2">
+                  Percent Decrease
+                </p>
+                <div className="font-mono text-center bg-white py-2 rounded text-amber-700 font-bold mb-2">
+                  New = Original × (1 − r)
+                </div>
+                <p className="text-xs text-slate-600">
+                  Where r is the rate as a decimal (e.g., 25% → r = 0.25)
+                </p>
+                <p className="text-xs text-slate-500 mt-1">
+                  Example: $200 decreased by 25% → 200 × 0.75 ={" "}
+                  <strong>$150</strong>
+                </p>
+              </div>
+            </div>
+            <div className="mt-4 bg-slate-100 p-4 rounded-xl border-l-4 border-amber-500 text-sm">
+              <p className="font-bold text-amber-900 mb-1">
+                Finding the Percent Change
+              </p>
+              <div className="font-mono text-center bg-white py-2 rounded text-slate-700 font-bold mb-1">
+                % Change = <Frac n="New − Old" d="Old" /> × 100
+              </div>
+              <p className="text-xs text-slate-600">
+                Positive result = increase. Negative result = decrease.
+              </p>
+              <p className="text-xs text-slate-500 mt-1">
+                Example: Old = 80, New = 100 → <Frac n="100 − 80" d="80" /> ×
+                100 = <strong>25% increase</strong>
+              </p>
+            </div>
+          </div>
+          <PercentChangeWidget />
+          <button
+            onClick={() => scrollToSection(3)}
+            className="mt-12 group flex items-center text-amber-600 font-bold hover:text-amber-800 transition-colors"
+          >
+            Next: Multi-Step Changes{" "}
+            <ArrowDown className="ml-2 w-5 h-5 group-hover:translate-y-1 transition-transform" />
+          </button>
+        </section>
+
+        {/* Section 4: Multi-Step Changes */}
+        <section
+          ref={(el) => {
+            sectionsRef.current[3] = el;
+          }}
+          className="min-h-screen flex flex-col justify-center mb-24"
+        >
+          <h2 className="text-4xl font-extrabold text-slate-900 mb-6">
+            Multi-Step Percent Changes
+          </h2>
+          <div className="prose prose-slate text-lg text-slate-600 mb-8">
+            <p>
+              <strong>Trap Alert:</strong> Percentages do not simply add up. An
+              increase of 20% followed by a decrease of 20% does{" "}
+              <strong>not</strong> bring you back to the start!
+            </p>
+            <div className="mt-4 bg-rose-50 border border-rose-200 rounded-xl p-5">
+              <p className="font-bold text-rose-900 mb-2">
+                Why 20% Up then 20% Down ≠ 0%
+              </p>
+              <div className="font-mono text-sm text-slate-700 space-y-1">
+                <div>
+                  Start: <strong>$100</strong>
+                </div>
+                <div>
+                  +20%: 100 × 1.20 = <strong>$120</strong>
+                </div>
+                <div>
+                  −20%: 120 × 0.80 = <strong>$96</strong> ← not $100!
+                </div>
+              </div>
+              <p className="text-xs text-slate-600 mt-2">
+                The decrease applies to the <em>new</em> (larger) amount, not
+                the original.
+              </p>
+            </div>
+            <div className="mt-4 bg-amber-50 border border-amber-200 rounded-xl p-5">
+              <p className="font-bold text-amber-900 mb-2">
+                The Multiplier Chain Method
+              </p>
+              <p className="text-sm text-slate-700 mb-2">
+                For any sequence of percent changes, multiply all the
+                multipliers together:
+              </p>
+              <div className="font-mono text-center bg-white py-2 rounded text-amber-700 font-bold mb-2">
+                Final = Original × m₁ × m₂ × m₃ × ...
+              </div>
+              <div className="font-mono text-sm text-slate-700 space-y-1">
+                <div>
+                  +20% then −20%: 1.20 × 0.80 = <strong>0.96</strong> →{" "}
+                  <strong>4% net decrease</strong>
+                </div>
+                <div>
+                  +50% then −50%: 1.50 × 0.50 = <strong>0.75</strong> →{" "}
+                  <strong>25% net decrease</strong>
+                </div>
+              </div>
+            </div>
+            <div className="mt-4 bg-slate-100 p-4 rounded-xl border-l-4 border-amber-500 text-sm">
+              <p className="font-bold text-amber-900 mb-1">
+                Compound Interest (Same Idea!)
+              </p>
+              <div className="font-mono text-center bg-white py-2 rounded text-slate-700 font-bold mb-1">
+                A = P × (1 + r)ⁿ
+              </div>
+              <p className="text-xs text-slate-600">
+                P = principal, r = annual rate (decimal), n = number of years.
+                This is just the multiplier chain with the same multiplier
+                repeated n times.
+              </p>
+              <p className="text-xs text-slate-500 mt-1">
+                Example: $1,000 at 5% for 3 years → 1000 × (1.05)³ ={" "}
+                <strong>$1,157.63</strong>
+              </p>
+            </div>
+          </div>
+          <MultiStepPercentWidget />
+          <button
+            onClick={() => scrollToSection(4)}
+            className="mt-12 group flex items-center text-amber-600 font-bold hover:text-amber-800 transition-colors"
+          >
+            Next: Practice Quiz{" "}
+            <ArrowDown className="ml-2 w-5 h-5 group-hover:translate-y-1 transition-transform" />
+          </button>
+        </section>
+
+        {/* Section 5: Quiz */}
+        <section
+          ref={(el) => {
+            sectionsRef.current[4] = el;
+          }}
+          className="min-h-screen flex flex-col justify-center"
+        >
+          <h2 className="text-4xl font-extrabold text-slate-900 mb-8">
+            Practice Time
+          </h2>
+          {allQuizzes.map((quiz, idx) => (
+            <div key={`quiz-${idx}`} className="mb-12">
+              <Quiz data={quiz} />
+            </div>
+          ))}
+          <div className="p-8 bg-amber-900 rounded-2xl text-white text-center mt-12">
+            <h3 className="text-2xl font-bold mb-4">Topic Mastered!</h3>
+            <button
+              onClick={onFinish}
+              className="px-6 py-3 bg-white text-amber-900 font-bold rounded-full hover:bg-amber-50 transition-colors"
+            >
+              Finish Lesson ✓
+            </button>
+          </div>
+        </section>
+      </div>
+    </div>
+  );
+};
+
+export default ProportionalLesson;