diff --git a/Natours/starter/css/style.css b/Natours/starter/css/style.css
index 16faf4a..a107e1d 100644
--- a/Natours/starter/css/style.css
+++ b/Natours/starter/css/style.css
@@ -53,17 +53,18 @@ body {
     top: 40%;
     left: 50%;
     transform: translate(-50%,-50%);
-
     /* 
      * Limpiar animaciones para evitar temblores 
      * No se sabe realmente por qué funciona o de dónde viene el error, pero lo hace
      */
     backface-visibility: hidden;
+    text-align: center;
 }
 
 .heading-primary {
     color: #fff;
     text-transform: uppercase;
+    margin-bottom: 60px;
 }
 
 .heading-primary-main {
@@ -71,15 +72,10 @@ body {
     font-size: 60px;
     font-weight: 400;
     letter-spacing: 35px;
-
-    animation-name: moveInLeft;
-    animation-duration: 1.2s;
-    animation-timing-function: ease-out;
-
-    /*
-    animation-delay: 3s;
-    animation-count: 3;
-    */
+    
+    animation-name: slideLeft;
+    animation-duration: 1s;
+    animation-timing-function: ease-in;
 }
 
 .heading-primary-sub {
@@ -87,41 +83,105 @@ body {
     font-size: 22px;
     font-weight: 700;
     letter-spacing: 16px;
-    /*
-    animation-name: moveInRight;
-    animation-duration: 1.2s;
-    */
-    animation: moveInRight 1.2s ease-out;
+    
+    animation-name: slideRight;
+    animation-duration: 1s;
+    animation-timing-function: ease-in;
 }
 
-@keyframes moveInLeft{
-    0%{
+@keyframes slideLeft {
+    0% {
+        transform: translateX(-160px);
         opacity: 0;
-        transform: translateX(-100px);
     }
 
-    80%{
-        transform: translateX(20px);
+    80% {
+        transform: translateX(15px);
     }
 
-    100%{
+    100% {
+        transform: translateX(0);
         opacity: 1;
-        transform: translate(0);
     }
 }
 
-@keyframes moveInRight{
-    0%{
+@keyframes slideRight {
+    0% {
+        transform: translateX(160px);
         opacity: 0;
-        transform: translateX(100px);
     }
 
-    80%{
-        transform: translateX(-20px);
+    80% {
+        transform: translateX(-15px);
     }
 
-    100%{
+    100% {
+        transform: translateX(0);
         opacity: 1;
-        transform: translate(0);
     }
+}
+
+@keyframes slideBottom {
+    0% {
+        transform: translateY(50px);
+        opacity: 0;
+    }
+
+    100% {
+        transform: translateY(0);
+        opacity: 1;
+    }
+}
+
+.btn:link,
+.btn:visited {
+    text-transform: uppercase;
+    text-decoration: none;
+    padding: 15px 40px;
+    display: inline-block;
+    border-radius: 100px;
+    transition: all 0.2s;
+    position: relative;
+}
+
+.btn-animated {
+    animation: slideBottom 0.7s ease-out .75s;
+    animation-fill-mode: backwards;
+}
+
+.btn:hover {
+    transform: translateY(-4px);
+    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
+}
+
+.btn:active {
+    transform: translateY(-1px);
+    box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
+}
+
+.btn-white {
+    background-color: #fff;
+    color: #777;
+}
+
+.btn::after {
+    content: "";
+    display: inline-block;
+    height: 100%;
+    width: 100%;
+    border-radius: 100px;
+    position: absolute;
+    top: 0;
+    left: 0;
+    z-index: -1;
+    transition: all 0.4s;
+}
+
+.btn-white::after{
+    background-color: #fff;
+}
+
+.btn:hover::after {
+    transform: scaleX(1.4) scaleY(1.6);
+    opacity: 0;
 }
\ No newline at end of file
diff --git a/Natours/starter/index.html b/Natours/starter/index.html
index 6f9e183..970972c 100644
--- a/Natours/starter/index.html
+++ b/Natours/starter/index.html
@@ -22,6 +22,8 @@
                     <span class="heading-primary-main">outdoors</span>
                     <span class="heading-primary-sub">is where life happens</span>
                 </h1>
+
+                <a href="#" class="btn btn-white btn-animated">Discover our tours</a>
             </div>
         </header>
     </body>
diff --git a/README.md b/README.md
index e0b1b5f..316aba1 100644
--- a/README.md
+++ b/README.md
@@ -7,3 +7,7 @@ Hay dos tipos de animaciones:
 - Con la propiedad 'transition'
 - Con keyframes
     - Lo ideal es solo animar con opacity y transform, porque los navegadores están optimizados para ellas dos solo.
+
+## Pseudo-elementos
+Estados especiales de un selector (:hover, :link, etc.)
+::after -> Add a virtual element 'after' el elemento