fix(guide): restructure curriculum guide articles (#36501)

* fix: restructure certifications guide articles
* fix: added 3 dashes line before prob expl
* fix: added 3 dashes line before hints
* fix: added 3 dashes line before solutions

guide/english/certifications/coding-interview-prep/project-euler/problem-5-smallest-multiple/index.md

@@ -1,39 +1,45 @@
 ---
 title: Smallest multiple
 ---
-## Problem 5: Smallest multiple
+# Problem 5: Smallest multiple
 
-### Method:
+---
+## Problem Explanation
 - In this challenge we need to find the LCM of 1 to n numbers. 
 - To find LCM of a number we use the following formula: 
   - ![lcm](https://wikimedia.org/api/rest_v1/media/math/render/svg/9453a93953efe119b7502c1827aeeb869ab121d6)
 - To find GCD (Greatest Common Divisor) of two number we use Euclidean algorithm.
 - Once we get LCM of two numbers, we can get LCM of the numbers from 1 to n.
 
-### Solution:
+
+---
+## Solutions
+<details><summary>Solution 1 (Click to Show/Hide)</summary>
+
 ```js
 //LCM of two numbers
-function lcm(a, b){
-  return (a*b)/gcd(a, b);
+function lcm(a, b) {
+  return (a * b) / gcd(a, b);
 }
 
-//Euclidean recursive algorithm 
-function gcd(a, b){
+//Euclidean recursive algorithm
+function gcd(a, b) {
   if (b === 0) return a;
-  return gcd(b, a%b);
+  return gcd(b, a % b);
 }
 
-function smallestMult(n){
+function smallestMult(n) {
   let maxLCM = 1;
-  
+
   //Getting the LCM in the range
-  for (let i = 2; i <= n; i++){
+  for (let i = 2; i <= n; i++) {
     maxLCM = lcm(maxLCM, i);
   }
   return maxLCM;
 }
 ```  
 
-### References:
+#### Relevant Links
 - [Euclidean algorithm](https://en.wikipedia.org/wiki/Euclidean_algorithm)
 - [LCM](https://en.wikipedia.org/wiki/Least_common_multiple)
+</details>