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HTML 

              
                <!-- BUTTON SHOW/HIDE INSTRUCTION -->
<input type="checkbox" id="u-instruction__button" name="u-instruction__button">
<label for="u-instruction__button" class="c-button c-instruction__button">
  <span class="c-button__off">OFF</span><span class="c-button__on">ON</span>
  <div class="c-instruction__button__frame">  
    <div class="c-button__instruction__toggle"></div>
  </div>
</label>
<div class="c-instruction__text">Switch the toggle for see different action buttons made with checkbox trick.</div>


<div class="c-mobile-view">
  <!-- CONTROLLERS -->
  <input type="checkbox" id="u-mobile__button" name="u-mobile__button">
  <input type="checkbox" id="u-topbar__button" name="u-topbar__button">
  <input type="checkbox" id="u-cards-switcher__button" name="u-cards-switcher__button">
  <input type="checkbox" id="u-cards-hide__button" name="u-cards-hide__button">
  <!-- / controllers-->

  <!-- MOBILE VIEW CONTAINER -->
  <div class="c-mobile-view__inner">

    <!-- TOPBAR -->
    <div class="c-mobile__topbar">
      <label for="u-topbar__button" class="c-button c-topbar__button--menu fa fa-bars"></label>
      <label for="u-topbar__button" class="c-button c-topbar__button--close fa fa-times"></label>
      <ul>
        <li><a href="" class="u-link__effect">Events list</a></li>
        <li><a href="" class="u-link__effect">Favorites</a></li>
        <li><a href="" class="u-link__effect">Credits</a></li>
      </ul>
    </div>

    <!-- CARDS -->
    <div class="c-cards__inner">
      <div class="c-card c-card--back">
        <div class="c-card__details">
          <div class="c-card__details__top">
            <h1>201-217 Central Park West</h1>
            <p>New York, NY 10024, Stati Uniti</p>
            <p>40.782093, -73.971731</p>
          </div>
          <div class="c-card__details__bottom">12<span>km</span></div>
        </div>
      </div>
      <div class="c-card c-card--front">
        <div class="c-card__details">
          <div class="c-card__details__top">
            <h1>284 5th Avenue</h1>
            <p>New York, NY 10001, Stati Uniti</p>
            <p>40.737330, -73.987470</p>
          </div>
          <div class="c-card__details__bottom">2.4<span>km</span></div>
        </div>
      </div>

      <!-- ANIMATED PIN -->
      <div class="c-pin"></div>
    </div>
  </div>

  <!-- OVERLAY -->
  <div class="c-overlay">
    <div class="c-overay__inner">
      <!-- BUTTON 1 -->
      <label for="u-mobile__button" class="c-button">
          <span class="c-overlay-inner__button fa fa-star button__1"></span>
        </label>
      <!-- BUTTON 2 -->
      <label for="u-mobile__button" class="c-button">
          <span class="c-overlay-inner__button fa fa-search button__2"></span>
        </label>
    </div>
  </div>

  <!-- SWITCHER CARDS BUTTON -->
  <label for="u-cards-switcher__button" class="c-button c-switcher__button">
      <span class="c-switcher__button--cards fa fa-refresh"></span>
  </label>

  <!-- HIDE CARDS BUTTON -->
  <label for="u-cards-hide__button" class="c-button c-show__button">
      <span class="c-show__button--cards fa fa-eye"></span>
  </label>
  <label for="u-cards-hide__button" class="c-button c-hide__button">
      <span class="c-hide__button--cards fa fa-eye-slash"></span>
  </label>

  <!-- BUTTON + -->
  <label for="u-mobile__button" class="c-button c-mobile__button">
      <span class="c-mobile__button__plus fa fa-plus"></span>
  </label>
  
  <!-- INSTRUCTION -->
  <div class="c-bubble__info c-bubble--menu"><div class="c-bubble__inner"><span>01</span><span>open menu</span></div></div>
  <div class="c-bubble__info c-bubble--plus"><div class="c-bubble__inner c-bubble__inner"><span>02</span><span>open plus menu</span></div></div>
  <div class="c-bubble__info c-bubble--switch"><div class="c-bubble__inner"><span>03</span><span>switch cards</span></div></div>
  <div class="c-bubble__info c-bubble--hide"><div class="c-bubble__inner"><span>04</span><span>hide cards</span></div></div>

</div>
!

CSS 

              
                @import 'https://fonts.googleapis.com/css?family=Roboto:400,900';
body { font-family: 'Roboto', sans-serif; font-size: 62.5%; }


//VARIBLES ----------------------------------------------------------------------
@col__black:    #160128;
@col__grey:     #747474;
@col__white:    #FFF;
@col__lightblu: #5873fe;
@col__purple:   #871cde;
@col__darkblu:  #192541;
@col__yellow:   #ecc54d;


//USEFUL LESS MIXIN -------------------------------------------------------------
.u-box-sizing (@type: border-box) {
	-webkit-box-sizing: @type;
	-moz-box-sizing:    @type;
	box-sizing:         @type;
}
.u-gradient (@startColor: @col__black, @endColor: @col__white) {
	background-color: @startColor;
	background: -webkit-gradient(linear, left top, right bottom, from(@startColor), to(@endColor));
	background: -moz-linear-gradient(top, @startColor, @endColor);
}
.u-border-radius (@radius: 5px) {
	-webkit-border-radius: @radius;
	-moz-border-radius:    @radius;
	border-radius:         @radius;
	-moz-background-clip:    padding;
	-webkit-background-clip: padding-box;
	background-clip:         padding-box;
}
.u-box-shadow (@string) {
	-webkit-box-shadow: @string;
	-moz-box-shadow:    @string;
	box-shadow:         @string;
}
.u-inner-shadow (@x: 0, @y: 1px, @blur: 2px, @alpha: 0.25) {
	-webkit-box-shadow: inset @x @y @blur rgba(255, 255, 255, @alpha);
	-moz-box-shadow:    inset @x @y @blur rgba(255, 255, 255, @alpha);
	box-shadow:         inset @x @y @blur rgba(255, 255, 255, @alpha);
}
.u-horizontal-center (@mleft) {
    left       : 50%;
    margin-left: @mleft;
}
.u-transform (@handler) {
    transform        : @handler;
    -webkit-transform: @handler;
}
.u-border (@border_size: 1px, @border_color: @col__white) {
  border: solid @border_size @border_color;
  -moz-border: solid @border_size @border_color;
  -webkit-border: solid @border_size @border_color;
}


//RESET  ------------------------------------------------------------------------
body  { background: darken(desaturate(@col__purple, 40%), 30%); }
input { display: none; } //important for hide the input checkbox
ul    { padding: 0; }
li    { list-style-type: none; }


//CONTAINER MOBILE VIEW ---------------------------------------------------------
.c-mobile-view {
  position:   relative;
  margin:     120px auto 0;
  width:      320px;
  height:     568px;
  background: url("https://www.lucapagot.it/mobile-codepen.jpg");
  background-position: bottom;
  background-size: cover;
  .u-animation-fadein (@duration: .5s, @delay: .1s,);
  .u-box-shadow (0 0 60px rgba(0,0,0,.6););
  .u-border-radius (@radius: 30px);
  &:before {
      position: absolute;
      content:  '';
      display:  block;
      top:      0;
      width:    100%;
      height:   100%;
      .u-inner-shadow (@x: 0, @y: -1px, @blur: 3px, @alpha: 0.2);
      .u-border-radius (@radius: 30px);
      .u-box-sizing (@type: border-box);
    }
}
.c-mobile-view__inner {
    overflow: hidden;
    width:    100%;
    height:   100%;
    .u-border-radius (@radius: 30px);
}


//PIN ------------------------------------------------------------------------
.c-pin {
  position: absolute;
  width:   36px;
  height:  36px;
  top:     120px;
  left:    160px;
  z-index: -1;
  .u-border-radius (@radius: 50%);
  .u-border (4px, @col__lightblu);
  .u-animation-infinite (@duration: 1.5s);
}


//BUTTON ------------------------------------------------------------------------
.c-button {
  cursor: pointer;
  font-size: 1.2em;
}
.c-mobile__button {
  position:    absolute;
  width:       68px;
  height:      68px;
  bottom:      -26px;
  line-height: 60px;
  text-align:  center;
  z-index:     2;
  color:       @col__white;
  border:      solid 6px rgba(255,255,255,.2);
  .u-animation-fadein (@duration: .5s, @delay: .4s,);
  .u-gradient (@startColor: @col__lightblu, @endColor: @col__purple);
  .u-box-shadow (0 0 10px darken(@col__white, 75%));
  .u-horizontal-center (@mleft: -34px);
  .u-border-radius (@radius: 50%);
  .u-box-sizing (@type: border-box);
  .u-trans(@duration: 0.4s);   
  &:hover {
    width:       80px;
    height:      80px;
    line-height: 77px;
    bottom:      -26px;
    border:      solid 4px rgba(255,255,255,.2);
    .u-horizontal-center (@mleft: -40px);
    }
   .c-mobile__button__plus {
    .u-trans();
  }
}

input[name=u-mobile__button]:checked ~ .c-mobile__button .c-mobile__button__plus {
    .u-transform(@handler: rotate(45deg));
    .u-trans(@duration:.6s);
} 


//TOPBAR ------------------------------------------------------------------------
.c-mobile__topbar {
  position:     relative;
  overflow:     hidden;
  width:        100%;
  height:       10%;
  .u-trans();
  .u-border-radius (@radius: 30px 30px 0 100%);
  .u-gradient (@startColor: @col__lightblu, @endColor: @col__purple);
  & a  { 
    text-decoration: none;   
    color:           @col__white;
    letter-spacing:  3px;
    font-size:       1.4em;  
    z-index:         1;
    .u-trans();  
    &:hover { .u-trans(); color: @col__yellow; }
  } 
  & ul { text-align: right; padding-top: 40px; }
  & li { margin: 30px 30px 40px 0; }
}

//EXPAND TOPBAR ON MENU CLICK
input[name=u-topbar__button]:checked ~ .c-mobile-view__inner .c-mobile__topbar  {
    height: 50%; 
    .u-trans(@duration:.6s);
}


//ANCHOR HOVER EFFCET -------------------------------------------------------------------
.u-link__effect {
  position: relative;  
  &:after {
    position:   absolute;
    content:    '';
    display:    block;
    right:      0;
    width:      0;
    bottom:     -4px;
    height:     2px;
    background: @col__yellow;
    .u-trans(@duration: 0.4s);
  }
  &:hover:after { 
    width: 100%;
    .u-trans();
  }
}


//TOPBAR BUTTON ----------------------------------------------------------------
.c-topbar__button--menu {
  position: absolute;
  right:    32px;
  top:      32px;
  z-index:  1;
  color:    @col__white;
  .u-transform (scale(1));
  .u-trans();
}

.c-topbar__button--close {
  position: absolute;
  right:    32px;
  top:      32px;
  z-index:  1;
  cursor:   pointer;
  color:    @col__white;
  .u-transform (scale(0));
  .u-trans();
}

//HIDE/SHOW MENU BUTTON ON CLICK
input[name=u-topbar__button]:checked ~ .c-mobile-view__inner .c-topbar__button--menu  {
    .u-transform (scale(0));
    .u-trans(@duration:.6s);
}

//SHOW/HIDE CLOSE BUTTON ON CLICK
input[name=u-topbar__button]:checked ~ .c-mobile-view__inner .c-topbar__button--close  {
    .u-transform (scale(1));
    .u-trans(@duration:.6s);
}


//SWITCHER CARDS BUTTON ----------------------------------------------------------------
.c-switcher__button {
  position: absolute;
  left:     20px;
  bottom:   20px;
  color:    @col__white;
}

.c-switcher__button--cards {
  .u-transform (rotate(0));
  .u-trans(@duration:.6s);
}

//ROTATE SWITCHER BUTTON ON CLICK
input[name=u-cards-switcher__button]:checked ~ .c-switcher__button .c-switcher__button--cards  {
  .u-transform (rotate(180deg));
  .u-trans(@duration:.6s);
}

//SWITCH CARDS ON CLICK
input[name=u-cards-switcher__button]:checked ~ .c-mobile-view__inner .c-card--back  {
  z-index: 1;
  opacity: 1;
  bottom:  60px;
  .u-trans(@duration:.6s);
  .u-transform (scale(1));
}

input[name=u-cards-switcher__button]:checked ~ .c-mobile-view__inner .c-card--front  {
  z-index: 0;
  opacity: .7;
  bottom:  30px;
  .u-trans(@duration:.6s);
  .u-transform (scale(0.9));
}

//HIDE CARDS ON CLICK 
.c-hide__button, .c-show__button {
  position: absolute;
  right:    20px;
  bottom:   20px;
  color:    @col__white;
}

.c-show__button--cards {
  .u-transform (scale(1));
  .u-trans(@duration:.6s);
}
.c-hide__button--cards {
  .u-transform (scale(0));
  .u-trans(@duration:.6s);
}


//HIDE/SHOW EYE BUTTON ON CLICK 
input[name=u-cards-hide__button]:checked ~ .c-show__button .c-show__button--cards  {
    .u-transform (scale(0));
    .u-trans(@duration:.6s);
}

//SHOW/HIDE EYE SLASH BUTTON ON CLICK 
input[name=u-cards-hide__button]:checked ~ .c-hide__button .c-hide__button--cards  {
    .u-transform (scale(1));
    .u-trans(@duration:.6s);
}

//HIDE/SHOW CARDS ON CLICK 
input[name=u-cards-hide__button]:checked ~ .c-mobile-view__inner .c-card  {
    opacity: 0;
    .u-trans(@duration:.6s);
}


// CARDS ------------------------------------------------------------------------
.cards__inner {
  position: relative;
}

.c-card {
  position:   absolute;
  bottom:     60px;
  width:      ~"calc(100% - 40px)"; //for use calc on LESS, close value inside  ~""
  margin:     0 20px;
  overflow:   hidden;
  opacity:    1;
  .u-trans(@duration:.8s);
  .u-box-shadow (0 0 10px 0 fade(@col__black, 90));
  .u-border-radius (@radius: 20px);
}

.c-card--back {
  bottom:     30px;
  opacity:    0.7;
  .u-transform (scale(0.9));
  .c-card__details__bottom { background: @col__purple; }
  .c-card__details__top { 
    h1 { color: @col__purple; } 
  }
}

.c-card__details {
  position: relative;
  height:   150px;
}

.c-card__details__top {
  .u-box-sizing;
  position:   absolute;
  height:     110px;
  top:        0;
  width:      100%;
  padding:    20px;
  background: @col__black;
  .u-border-radius (@radius: 20px 20px 0 0);
  h1 { font-size: 1.6em; color: @col__lightblu; font-size: 1.6em; margin: 0; }
  p { color: @col__white; font-size: 1.1em; margin: 6px 0; }
  p:last-child { color: @col__grey;  font-size: 1em; margin: 14px 0; }
}

.c-card__details__bottom {
  position:    absolute;
  height:      40px;
  width:       100%;
  bottom:      0;
  text-align:  center;
  line-height: 40px;
  font-size:   1.6em;
  font-weight: 900;
  background: fade(@col__lightblu, 80%);
  .u-border-radius (@radius: 0 0 20px 20px);
  & span { font-size: 0.7em; padding-left: 6px; }
}


// OVERLAY ----------------------------------------------------------------------
.c-overlay {
  position:   absolute;
  top:        0;
  width:      100%;
  height:     100%;
  background: fade(@col__black, 80%);
  opacity:    0;
  .u-border-radius (@radius: 30px);
  .u-trans(@duration:.4s, @easing: ease-in-out)
}

//SHOW BLACK OVERLAY ON + CLICK
input[name=u-mobile__button]:checked ~ .c-overlay {
   opacity: 1;
   z-index: 1;
  .u-trans(@easing: ease-in-out);
} 


//OVERLAY INNER BUTTONS ------------------------------------------------------------------
.c-overlay__inner {
  position: relative;
  width:    100%;
  height:   100%;
}

.c-overlay-inner__button {
  position:    absolute;
  left:        ~"calc(50% - 30px)";
  width:       60px;
  height:      60px;
  text-align:  center;
  line-height: 60px;
  background:  @col__white;
  color:       @col__purple;
  .u-border-radius (@radius: 50%);
  .u-transform (scale(0));
  &:hover {
    color: @col__yellow;
    .u-trans();
  }
  &.button__1 {
    transition-delay:         .1s;
    -webkit-transition-delay: .1s;
    -moz-transition-delay:    .1s;
    bottom:                   80px;
  }
  &.button__2 {
    transition-delay:         .2s;
    -webkit-transition-delay: .2s;
    -moz-transition-delay:    .2s;
    bottom:                   160px;
  }
}

//SHOW BUTTONS INSIDE OVERLAY ON CLICK
input[name=u-mobile__button]:checked ~ .c-overlay .c-overlay-inner__button {
   z-index: 1;
  .u-transform (scale(1));
  .u-trans(@duration: .6s);
} 

// INSTRUCTION -----------------------------------------------------
.c-bubble__info {
  position: absolute;
  width:      100px;
  height:     100px;
  background: @col__white;
  margin:     20px;
  .u-border-radius (@radius: 50%);  
  
  &.c-bubble--plus   { 
    left:   ~"calc(50% - 70px)"; 
    bottom: -160px;
    .u-transform (scale(0));
    .u-trans(@duration: .4s, @delay: 0);
  }
  &.c-bubble--switch { 
    left:  -45px;
    .u-transform (scale(0));
    .u-trans(@duration: .4s, @delay: 0);
  }
  &.c-bubble--hide { 
    right:   -45px;
    .u-transform (scale(0));
    .u-trans(@duration: .4s, @delay: 0);
  }
  &.c-bubble--menu { 
    right: -130px; 
    top:   -30px;
    .u-transform (scale(0));
    .u-trans(@duration: .4s, @delay: 0);
  }
}

//SHOW/HIDE INSTRUCTION BUBBLE
input[name=u-instruction__button]:checked + label ~ .c-mobile-view .c-bubble--menu {
  .u-transform (scale(1));
  .u-trans (@duration: .4s, @delay: 0s);
} 
input[name=u-instruction__button]:checked + label ~ .c-mobile-view .c-bubble--plus {
  .u-transform (scale(1));
  .u-trans (@duration: .4s, @delay: .5s);
} 
input[name=u-instruction__button]:checked + label ~ .c-mobile-view .c-bubble--switch {
  .u-transform (scale(1));
  .u-trans (@duration: .4, @delay: 1s);
} 
input[name=u-instruction__button]:checked + label ~ .c-mobile-view .c-bubble--hide {
  .u-transform (scale(1));
  .u-trans (@duration: .4s, @delay: 1.5s);
} 

// BUBBLE INNER CONTAINER ------------------------------------------------------
.c-bubble__inner {
  position:   relative;
  width:      100px;
  height:     100px;
  text-align: center;
  &:before {
    content:  '';
    display:  block;
    position: absolute;
    width:    30px;
    height:   30px;
    z-index:  -1;
    background: @col__white;
    .u-horizontal-center (-15px);
    .u-transform (rotate(45deg));
  }  
  span { 
    display:     block; 
    font-size:   2.4em;
    padding-top: 26px;
    font-weight: 900;
  }
  span:last-child { font-size: 1.2em; padding-top: 0; font-weight: 400;
  }
}

.c-bubble__info.c-bubble--menu .c-bubble__inner:before {
    left:        0px;
    top:         35px;
    margin-left: 0; 
}

// INSTRUCTION BUTTON -----------------------------------------------------------
.c-instruction__button {
  position:   fixed;
  bottom:     20px;
  left:       20px;
  width:      80px;
  height:     40px;
  background: @col__white;
  overflow:   hidden;
  .u-border-radius (@radius: 3px);
}

.c-button__instruction__toggle {
  position:   absolute;
  left:       0;
  width:      40px;
  height:     40px;
  background: @col__purple;
  .u-box-sizing;
  .u-trans (@duration: .2s,  @easing: ease-in-out);
  .u-border-radius (@radius: 4px);
  .u-border (@border_size: 2px, @border_color: @col__white)
}

.c-button__off {
  position: absolute;
  line-height: 40px;
  width: 40px;
  text-align: center;
  color: @col__grey;
}
.c-button__on {
  .c-button__off;
  right: 0;
}

input[name=u-instruction__button]:checked + label .c-button__instruction__toggle {
    left: 40px;
    background: @col__lightblu;
    .u-trans (@duration: .2s, @easing: ease-in-out);
} 

.c-instruction__text {
  position:    fixed;
  bottom:      15px;
  left:        120px;
  width:       260px;
  font-size:   1.4em;
  line-height: 1.8em;
  color: @col__lightblu; 
}


// TRANSITIONS + ANIMATIONS -----------------------------------------------------
.u-trans(@property : all, @duration: 0.3s, @easing :  cubic-bezier(0.68, -0.55, 0.265, 1.55), @delay : 0 ) {
 transition-property: @property;
 transition-duration: @duration;
 transition-timing-function: @easing;
 transition-delay: @delay;
 -webkit-transition-property: @property;
 -webkit-transition-duration: @duration;
 -webkit-transition-timing-function: @easing;
 -webkit-transition-delay: @delay;
}
@keyframes animation-fadein {
   from { transform: scale(0); opacity: 0; }
   to   { transform: scale(1); opacity: 1; }
}
@-webkit-keyframes animation-fadein {
   from { -webkit-transform: scale(0); opacity: 0; }
   to   { -webkit-transform: scale(1); opacity: 1; }
}

.u-animation-fadein (@duration: 1s, @delay: 1s,) {
    opacity                    : 0;
    animation-name             : animation-fadein;
    animation-duration         : @duration;
    animation-delay            : @delay;
    animation-fill-mode        : forwards;
    animation-timing-function  : cubic-bezier(0.68, -0.55, 0.265, 1.55);
    -webkit-animation-name     : animation-fadein;
    -webkit-animation-duration : @duration;
    -webkit-animation-delay    : @delay;
    -webkit-animation-fill-mode: forwards;
    -webkit-animation-timing-function  : cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes animation-fadein-infinite {
   from { transform: scale(0); opacity: 1; }
   to   { transform: scale(1); opacity: 0; }
}
@-webkit-keyframes animation-fadein-infinite {
   from { -webkit-transform: scale(0); opacity: 1; }
   to   { -webkit-transform: scale(1); opacity: 0; }
}

.u-animation-infinite (@duration: 1.5s) {
    opacity                    : 0;
    animation-name             : animation-fadein-infinite;
    animation-duration         : @duration;
    animation-timing-function  : easy-in-out;
    animation-iteration-count  : infinite;
    -webkit-animation-name     : animation-fadein-infinite;
    -webkit-animation-duration : @duration;
    -webkit-animation-timing-function: easy-in-out;
    -webkit-animation-iteration-count: infinite;
}
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