style.css

html {
  box-sizing: border-box;
  background: #ffc600;
  font-family: "Kavoon";
  font-size: 20px;
  font-weight: 200;
}

body {
  margin: 0;
}

*,
*:before,
*:after {
  box-sizing: inherit;
}

.panels {
  min-height: 100vh;
  overflow: hidden;
  display: flex;
}

.panel {
  background: #6b0f9c;
  box-shadow: inset 0 0 0 5px rgba(255, 255, 255, 0.1);
  color: white;
  text-align: center;
  align-items: center;
  /* Safari transitionend event.propertyName === flex */
  /* Chrome + FF transitionend event.propertyName === flex-grow */
  transition: font-size 0.7s cubic-bezier(0.61, -0.19, 0.7, -0.11),
    flex 0.7s cubic-bezier(0.61, -0.19, 0.7, -0.11), background 0.2s;
  font-size: 20px;
  background-size: cover;
  background-position: center;
  flex: 1;
  justify-content: center;
  display: flex;
  flex-direction: column;
}

.panel1 {
  background-image: url("./Against\ all\ odds.png");
}
.panel2 {
  background-image: url("./change.png");
}
.panel3 {
  background-image: url("./Go\ for\ it.png");
}
.panel4 {
  background-image: url("./I’ll\ be\ there.png");
}
.panel5 {
  background-image: url("./Never\ give\ up.png");
}

/* Flex Items */
.panel > * {
  margin: 0;
  width: 100%;
  transition: transform 0.5s;
  flex: 1 0 auto;
  display: flex;
  justify-content: center;
  align-items: center;
}

.panel > *:first-child {
  transform: translateY(-100%);
}
.panel.open-active > *:first-child {
  transform: translateY(0);
}
.panel > *:last-child {
  transform: translateY(100%);
}
.panel.open-active > *:last-child {
  transform: translateY(0);
}

.panel p {
  text-transform: uppercase;
  font-family: "Amatic SC", cursive;
  text-shadow: 0 0 4px rgba(0, 0, 0, 0.72), 0 0 14px rgba(0, 0, 0, 0.45);
  font-size: 2em;
}

.panel p:nth-child(2) {
  transition: transform 0.5s;
  display: none;
  font-size: 3em;
}

.panel.open {
  flex: 5;
  font-size: 40px;
}

/* 
  ===========================================================================     
  
   */

.container {
  position: fixed;
  top: 0px;
  left: 0px;
  width: 100%;
  height: 100%;
  z-index: 0;
  background: -webkit-radial-gradient(
    rgba(0, 0, 0, 0.1),
    rgba(0, 0, 0, 0.3) 35%,
    rgba(0, 0, 0, 0.7)
  );
  background: -moz-radial-gradient(
    rgba(0, 0, 0, 0.1),
    rgba(0, 0, 0, 0.3) 35%,
    rgba(0, 0, 0, 0.7)
  );
  background: -ms-radial-gradient(
    rgba(0, 0, 0, 0.1),
    rgba(0, 0, 0, 0.3) 35%,
    rgba(0, 0, 0, 0.7)
  );
  background: radial-gradient(
    rgba(0, 0, 0, 0.1),
    rgba(0, 0, 0, 0.3) 35%,
    rgba(0, 0, 0, 0.7)
  );
}
.content {
  background: black;
  position: absolute;
  width: 100%;
  height: 100%;
  left: 0px;
  top: 0px;
  z-index: 1000;
}
.container h2 {
  position: absolute;
  top: 50%;
  line-height: 100px;
  height: 100px;
  margin-top: -50px;
  font-size: 100px;
  width: 100%;
  text-align: center;
  color: transparent;
  animation: blurFadeInOut 3s ease-in backwards;
}
.container h2.frame-1 {
  animation-delay: 0s;
}
.container h2.frame-2 {
  animation-delay: 2.5s;
}
.container h2.frame-3 {
  animation-delay: 5s;
}
.container h2.frame-4 {
  animation-delay: 7.5s;
}
.container h2.frame-5 {
  animation: none;
  color: transparent;
  text-shadow: 0px 0px 1px #fff;
}
.container h2.frame-5 span {
  animation: blurFadeIn 3s ease-in 12s backwards;
  color: transparent;
  text-shadow: 0px 0px 1px #fff;
}
.container h2.frame-5 span:nth-child(2) {
  animation-delay: 13s;
}
.container h2.frame-5 span:nth-child(3) {
  animation-delay: 14s;
}

@keyframes blurFadeInOut {
  0% {
    opacity: 0;
    text-shadow: 0px 0px 40px #fff;
    transform: scale(0.9);
  }
  20%,
  75% {
    opacity: 1;
    text-shadow: 0px 0px 1px #fff;
    transform: scale(1);
  }
  100% {
    opacity: 0;
    text-shadow: 0px 0px 50px #fff;
    transform: scale(0);
  }
}
@keyframes blurFadeIn {
  0% {
    opacity: 0;
    text-shadow: 0px 0px 40px #fff;
    transform: scale(1.3);
  }
  50% {
    opacity: 0.5;
    text-shadow: 0px 0px 10px #fff;
    transform: scale(1.1);
  }
  100% {
    opacity: 1;
    text-shadow: 0px 0px 1px #fff;
    transform: scale(1);
  }
}
@keyframes fadeInBack {
  0% {
    opacity: 0;
    transform: scale(0);
  }
  50% {
    opacity: 0.4;
    transform: scale(2);
  }
  100% {
    opacity: 0.2;
    transform: scale(5);
  }
}

@media only screen and (max-width: 600px) {
  .panel p {
    font-size: 1em;
  }
}