diff --git a/src/app/app.ts b/src/app/app.ts
index 957de88..6aba061 100644
--- a/src/app/app.ts
+++ b/src/app/app.ts
@@ -1,4 +1,4 @@
-import { Component } from '@angular/core';
+import { Component, OnInit } from '@angular/core';
 import { RouterOutlet } from '@angular/router';
 
 @Component({
@@ -7,5 +7,15 @@ import { RouterOutlet } from '@angular/router';
   templateUrl: './app.html',
   styleUrl: './app.css'
 })
-export class App {
+export class App implements OnInit {
+  ngOnInit(): void {
+    this.initTheme();
+  }
+
+  private initTheme(): void {
+    const savedTheme = localStorage.getItem('theme');
+    if (savedTheme === 'dark') {
+      document.documentElement.setAttribute('data-theme', 'dark');
+    }
+  }
 }
diff --git a/src/app/pages/welcome/welcome.component.css b/src/app/pages/welcome/welcome.component.css
index 9c86a94..edc7ffb 100644
--- a/src/app/pages/welcome/welcome.component.css
+++ b/src/app/pages/welcome/welcome.component.css
@@ -8,6 +8,180 @@
   position: relative;
 }
 
+.theme-toggle-container {
+  position: absolute;
+  top: 20px;
+  right: 20px;
+  z-index: 100;
+}
+
+.switch {
+  display: inline-block;
+  position: relative;
+}
+
+.switch__input {
+  clip: rect(1px, 1px, 1px, 1px);
+  clip-path: inset(50%);
+  height: 1px;
+  width: 1px;
+  margin: -1px;
+  overflow: hidden;
+  padding: 0;
+  position: absolute;
+}
+
+.switch__label {
+  position: relative;
+  display: inline-block;
+  width: 120px;
+  height: 60px;
+  background-color: #2B2B2B;
+  border: 5px solid #5B5B5B;
+  border-radius: 9999px;
+  cursor: pointer;
+  transition: all 0.4s cubic-bezier(.46,.03,.52,.96);
+}
+
+.switch__indicator {
+  position: absolute;
+  top: 50%;
+  left: 50%;
+  transform: translate(-50%, -50%) translateX(-72%);
+  display: block;
+  width: 40px;
+  height: 40px;
+  background-color: #7B7B7B;
+  border-radius: 9999px;
+  box-shadow: 10px 0px 0 0 rgba(0, 0, 0, 0.2) inset;
+  transition: all 0.4s cubic-bezier(.46,.03,.52,.96);
+}
+
+.switch__indicator::before,
+.switch__indicator::after {
+  position: absolute;
+  content: '';
+  display: block;
+  background-color: #FFFFFF;
+  border-radius: 9999px;
+  transition: all 0.4s cubic-bezier(.46,.03,.52,.96);
+}
+
+.switch__indicator::before {
+  top: 7px;
+  left: 7px;
+  width: 9px;
+  height: 9px;
+  opacity: 0.6;
+}
+
+.switch__indicator::after {
+  bottom: 8px;
+  right: 6px;
+  width: 14px;
+  height: 14px;
+  opacity: 0.8;
+}
+
+.switch__decoration {
+  position: absolute;
+  top: 65%;
+  left: 50%;
+  display: block;
+  width: 5px;
+  height: 5px;
+  background-color: #FFFFFF;
+  border-radius: 9999px;
+  animation: twinkle-stars 0.8s infinite -0.6s;
+  transition: all 0.4s cubic-bezier(.46,.03,.52,.96);
+}
+
+.switch__decoration::before,
+.switch__decoration::after {
+  position: absolute;
+  display: block;
+  content: '';
+  width: 5px;
+  height: 5px;
+  background-color: #FFFFFF;
+  border-radius: 9999px;
+}
+
+.switch__decoration::before {
+  top: -20px;
+  left: 10px;
+  opacity: 1;
+  animation: twinkle-stars 0.6s infinite;
+}
+
+.switch__decoration::after {
+  top: -7px;
+  left: 30px;
+  animation: twinkle-stars 0.6s infinite -0.2s;
+}
+
+@keyframes twinkle-stars {
+  50% { opacity: 0.2; }
+}
+
+.switch__input:checked + .switch__label {
+  background-color: #8FB5F5;
+  border-color: #347CF8;
+}
+
+.switch__input:checked + .switch__label .switch__indicator {
+  background-color: #ECD21F;
+  box-shadow: none;
+  transform: translate(-50%, -50%) translateX(72%);
+}
+
+.switch__input:checked + .switch__label .switch__indicator::before,
+.switch__input:checked + .switch__label .switch__indicator::after {
+  display: none;
+}
+
+.switch__input:checked + .switch__label .switch__decoration {
+  top: 50%;
+  transform: translate(0%, -50%);
+  animation: cloud 8s linear infinite;
+  width: 20px;
+  height: 20px;
+}
+
+.switch__input:checked + .switch__label .switch__decoration::before {
+  width: 10px;
+  height: 10px;
+  top: auto;
+  bottom: 0;
+  left: -8px;
+  animation: none;
+}
+
+.switch__input:checked + .switch__label .switch__decoration::after {
+  width: 15px;
+  height: 15px;
+  top: auto;
+  bottom: 0;
+  left: 16px;
+  animation: none;
+}
+
+.switch__input:checked + .switch__label .switch__decoration,
+.switch__input:checked + .switch__label .switch__decoration::before,
+.switch__input:checked + .switch__label .switch__decoration::after {
+  border-radius: 9999px 9999px 0 0;
+}
+
+.switch__input:checked + .switch__label .switch__decoration::after {
+  border-bottom-right-radius: 9999px;
+}
+
+@keyframes cloud {
+  0% { transform: translate(0%, -50%); }
+  50% { transform: translate(-50%, -50%); }
+  100% { transform: translate(0%, -50%); }
+}
+
 .clouds-container {
   display: flex;
   justify-content: center;
@@ -100,7 +274,7 @@
   top: -10px;
   left: 50%;
   transform: translateX(-50%);
-  width: 100px;
+  width: 75px;
   height: 15px;
   border: 2px solid rgba(255, 215, 0, 0.7);
   border-radius: 50%;
@@ -196,6 +370,21 @@ p {
 }
 
 @media (max-width: 768px) {
+  .theme-toggle-container {
+    top: 10px;
+    right: 10px;
+  }
+
+  .switch__label {
+    width: 100px;
+    height: 50px;
+  }
+
+  .switch__indicator {
+    width: 33px;
+    height: 33px;
+  }
+
   .welcome-shell {
     padding: var(--size-lg);
   }
diff --git a/src/app/pages/welcome/welcome.component.html b/src/app/pages/welcome/welcome.component.html
index d4f84c9..d5b67d8 100644
--- a/src/app/pages/welcome/welcome.component.html
+++ b/src/app/pages/welcome/welcome.component.html
@@ -1,4 +1,13 @@
 <main class="welcome-shell">
+  <div class="theme-toggle-container">
+    <div class="switch">
+      <input type="checkbox" class="switch__input" id="themeToggle" (change)="toggleDarkMode()" [checked]="!isDarkMode()">
+      <label class="switch__label" for="themeToggle">
+        <span class="switch__indicator"></span>
+        <span class="switch__decoration"></span>
+      </label>
+    </div>
+  </div>
   <div class="clouds-container">
     <div class="cloud cloud-left">
       <img src="arabian-chess/player-one.gif" alt="Player One" class="cloud-gif" />
diff --git a/src/app/pages/welcome/welcome.component.ts b/src/app/pages/welcome/welcome.component.ts
index e13a0da..3f3c149 100644
--- a/src/app/pages/welcome/welcome.component.ts
+++ b/src/app/pages/welcome/welcome.component.ts
@@ -24,7 +24,16 @@ export class WelcomeComponent {
   constructor(
     private readonly router: Router,
     private readonly gameApi: GameApiService
-  ) {}
+  ) {
+    this.initTheme();
+  }
+
+  private initTheme(): void {
+    const savedTheme = localStorage.getItem('theme');
+    if (savedTheme === 'dark') {
+      document.documentElement.setAttribute('data-theme', 'dark');
+    }
+  }
 
   startOneVsOne(): void {
     if (this.creating) {
@@ -108,4 +117,21 @@ export class WelcomeComponent {
     this.gameIdInput = '';
     this.errorMessage = '';
   }
+
+  toggleDarkMode(): void {
+    const htmlElement = document.documentElement;
+    const isDarkMode = htmlElement.getAttribute('data-theme') === 'dark';
+    
+    if (isDarkMode) {
+      htmlElement.removeAttribute('data-theme');
+      localStorage.removeItem('theme');
+    } else {
+      htmlElement.setAttribute('data-theme', 'dark');
+      localStorage.setItem('theme', 'dark');
+    }
+  }
+
+  isDarkMode(): boolean {
+    return document.documentElement.getAttribute('data-theme') === 'dark';
+  }
 }
diff --git a/src/styles-variables.css b/src/styles-variables.css
index 0d782a0..32b9dc3 100644
--- a/src/styles-variables.css
+++ b/src/styles-variables.css
@@ -2,19 +2,20 @@
    COLOR VARIABLES - Semantic Naming
    ======================================== */
 
-:root {
-  /* Primary Colors */
+/* Light Mode Colors (Default) */
+:root:not([data-theme='dark']) {
+  /* Primary Colors - Light Mode */
   --color-primary: #BA6D4B;
   --color-primary-dark: #5A2C28;
   --color-primary-light: #F3C8A0;
 
-  /* Secondary Colors */
+  /* Secondary Colors - Light Mode */
   --color-secondary-mint: #B9DAD1;
   --color-secondary-blue: #B9C2DA;
   --color-secondary-purple: #C19EF5;
   --color-secondary-lime: #E1EAA9;
 
-  /* Functional Colors */
+  /* Functional Colors - Light Mode */
   --color-bg-main: #F3C8A0;
   --color-bg-board: #B9DAD1;
   --color-bg-card: #E1EAA9;
@@ -26,6 +27,36 @@
   --color-text-primary: #5A2C28;
   --color-text-button-hover: #F3C8A0;
   --color-border: #5A2C28;
+}
+
+/* Dark Mode Colors */
+:root[data-theme='dark'] {
+  /* Primary Colors - Dark Mode */
+  --color-primary: #1a3a52;
+  --color-primary-dark: #0f1f2e;
+  --color-primary-light: #2d5a7b;
+
+  /* Secondary Colors - Dark Mode */
+  --color-secondary-mint: #4a7c7c;
+  --color-secondary-blue: #5a6fa5;
+  --color-secondary-purple: #7d5fa8;
+  --color-secondary-lime: #6b8e23;
+
+  /* Functional Colors - Dark Mode */
+  --color-bg-main: #1a2f47;
+  --color-bg-board: #2d5a7b;
+  --color-bg-card: #3d4e63;
+  --color-bg-input: #2d4a6f;
+  --color-bg-input-focus: #3d5a8f;
+  --color-bg-button: #5a7da5;
+  --color-bg-button-hover: #7a9dc5;
+
+  --color-text-primary: #e8f0f8;
+  --color-text-button-hover: #ffffff;
+  --color-border: #4a7c9c;
+}
+
+:root {
 
   /* ========================================
      TYPOGRAPHY SIZES
diff --git a/src/styles.css b/src/styles.css
index 7354bb7..fa5a81b 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -5,13 +5,57 @@
   box-sizing: border-box;
 }
 
+/* Light Mode (Default) */
+html:not([data-theme='dark']),
+html:not([data-theme='dark']) body {
+  background: linear-gradient(160deg, var(--color-primary-light), var(--color-secondary-mint));
+  color: var(--color-text-primary);
+}
+
+html:not([data-theme='dark']) body::before {
+  display: none;
+}
+
+/* Dark Mode */
+html[data-theme='dark'],
+html[data-theme='dark'] body {
+  background: #0f1f2e;
+  background-image: 
+    radial-gradient(2px 2px at 20px 30px, rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0)),
+    radial-gradient(2px 2px at 60px 70px, rgba(255, 255, 255, 0.9), rgba(255, 255, 255, 0)),
+    radial-gradient(1px 1px at 50px 50px, rgba(255, 255, 255, 0.7), rgba(255, 255, 255, 0)),
+    radial-gradient(1px 1px at 130px 80px, rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0)),
+    radial-gradient(2px 2px at 90px 10px, rgba(255, 255, 255, 0.6), rgba(255, 255, 255, 0)),
+    radial-gradient(1px 1px at 130px 120px, rgba(255, 255, 255, 0.9), rgba(255, 255, 255, 0)),
+    radial-gradient(2px 2px at 10px 90px, rgba(255, 255, 255, 0.7), rgba(255, 255, 255, 0)),
+    radial-gradient(1px 1px at 40px 120px, rgba(255, 255, 255, 0.8), rgba(255, 255, 255, 0));
+  background-repeat: repeat;
+  background-size: 150px 150px;
+  background-attachment: fixed;
+  color: var(--color-text-primary);
+}
+
+html[data-theme='dark'] body::before {
+  content: '';
+  position: fixed;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background: 
+    radial-gradient(circle at 20% 80%, rgba(45, 90, 123, 0.1) 0%, transparent 50%),
+    radial-gradient(circle at 80% 20%, rgba(90, 111, 165, 0.1) 0%, transparent 50%),
+    radial-gradient(circle at 50% 50%, rgba(29, 53, 82, 0.05) 0%, transparent 50%);
+  pointer-events: none;
+  z-index: -1;
+}
+
 html,
 body {
   margin: 0;
   min-height: 100%;
   font-family: "Comic Sans MS", "Comic Sans", cursive;
-  background: linear-gradient(160deg, var(--color-primary-light), var(--color-secondary-mint));
-  color: var(--color-text-primary);
+  position: relative;
 }
 
 button,