span inside div hover effect letter spacing effect

Issue

I have the following code for a span inside a div:

<div class="mission-button"><span class="mission">view our mission</span></div>

And the following css:

.mission-button::before {
    content:'';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    transition: all 1s;
    border-left-width: 2px;
    border-right-width: 2px;
    border-left-style: solid;
    border-right-style: solid;
    background-color: transparent;
    border-color: var(--main-dark); 
    animation: borderOnLoad 2s forwards;
}

@keyframes changeColor {
    0% {
        letter-spacing: 0px;
        color: white;
    }
    100% {
        letter-spacing: 2px;
        color: var(--main-dark);
    }
}

@keyframes borderOnLoad {
    0% {
        width: 100%;
        border-left-width: 3px;
        border-right-width: 3px;
        height: 100%;   
        top: 0;
        color: white;
        background-color: var(--main-dark);
    }
    50% {
        width: 200%;    
        left: -150px;
        border-left-width: 3px; 
        border-right-width: 3px;    
        height: 100%;   
        top: 0;
        color: white;
    } 
    100% {
        width: 65%;
        left: -150px;
        border-left-width: 200px;
        border-right-width: 200px;  
        height: 1px;
        top: 30px;
        color: var(--main-dark);    
        background-color: transparent;
    }
}

.mission-button {
    padding: 20px;
    /* background-color: #083958;*/
    cursor: pointer;
    width: 50%;
    position: relative;
    margin-top: 20px;   
    font-size: 20px;
    text-align: center;
}

.mission {
    letter-spacing: 0px;    
    -webkit-transition: all 1s ease;    
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
    cursor: pointer;
    animation: changeColor 2s forwards;
}   

.mission-button:hover .mission {
    letter-spacing: 5px;    
}

.mission-button:hover::before {
    width: 32%;
    border-left-width: 200px;
    border-right-width: 200px;  
    height: 1px;
    top: 30px;
}   

The changeColor and borderOnLoad animations are working as expected but when I hover the div, I'd like the span to change it's letter-spacing via:

.mission {
    letter-spacing: 0px;    
    -webkit-transition: all 1s ease;    
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
    cursor: pointer;
    animation: changeColor 2s forwards;
}   

.mission-button:hover .mission {
    letter-spacing: 5px;    
}

but it's doing anything. I'm thinking it's because there's already an animation for the mission-button and that one is taking priority over the rest, but I don't know

Solution

This is because you've set the animation-fill-mode to forwards, which maintains the styles of the last keyframe, including line-spacing:2px. It might make more sense to move the original line-spacing of 2px from the last keyframe to .mission:

@keyframes changeColor {
    0% {
        letter-spacing: 0px;
        color: white;
    }
    100% {
        color: black;
    }
}

.mission {
    letter-spacing: 2px;    
    -webkit-transition: all 1s ease;    
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
    cursor: pointer;
    animation: changeColor 2s forwards;
}   

.mission-button:hover .mission{
    letter-spacing: 5px;    
}

.mission-button::before {
    content:'';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    transition: all 1s;
    border-left-width: 2px;
    border-right-width: 2px;
    border-left-style: solid;
    border-right-style: solid;
    background-color: transparent;
    border-color: black; 
    animation: borderOnLoad 2s forwards;
}

@keyframes changeColor {
    0% {
        letter-spacing: 0px;
        color: white;
    }
    100% {
        color: black;
    }
}

@keyframes borderOnLoad {
    0% {
        width: 100%;
        border-left-width: 3px;
        border-right-width: 3px;
        height: 100%;   
        top: 0;
        color: white;
        background-color: black;
    }
    50% {
        width: 200%;    
        left: -150px;
        border-left-width: 3px; 
        border-right-width: 3px;    
        height: 100%;   
        top: 0;
        color: white;
    } 
    100% {
        width: 65%;
        left: -150px;
        border-left-width: 200px;
        border-right-width: 200px;  
        height: 1px;
        top: 30px;
        color: black;    
        background-color: transparent;
    }
}

.mission-button {
    padding: 20px;
    /* background-color: #083958;*/
    cursor: pointer;
    width: 50%;
    position: relative;
    margin-top: 20px;   
    font-size: 20px;
    text-align: center;
}

.mission {
    letter-spacing: 2px;    
    -webkit-transition: all 1s ease;    
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
    cursor: pointer;
    animation: changeColor 2s forwards;
}   

.mission-button:hover .mission{
    letter-spacing: 5px;    
}

.mission-button:hover::before {
    width: 32%;
    border-left-width: 200px;
    border-right-width: 200px;  
    height: 1px;
    top: 30px;
}   

  <div class="mission-button"><span class="mission">view our mission</span></div>

If you can't change the original spacing, to overwrite it you can either use !important:

.mission-button:hover .mission{
    letter-spacing: 5px !important;    
}

.mission-button::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  transition: all 1s;
  border-left-width: 2px;
  border-right-width: 2px;
  border-left-style: solid;
  border-right-style: solid;
  background-color: transparent;
  border-color: black;
  animation: borderOnLoad 2s forwards;
}

@keyframes changeColor {
  0% {
    letter-spacing: 0px;
    color: white;
  }
  100% {
    letter-spacing: 2px;
    color: black;
  }
}

@keyframes borderOnLoad {
  0% {
    width: 100%;
    border-left-width: 3px;
    border-right-width: 3px;
    height: 100%;
    top: 0;
    color: white;
    background-color: black;
  }
  50% {
    width: 200%;
    left: -150px;
    border-left-width: 3px;
    border-right-width: 3px;
    height: 100%;
    top: 0;
    color: white;
  }
  100% {
    width: 65%;
    left: -150px;
    border-left-width: 200px;
    border-right-width: 200px;
    height: 1px;
    top: 30px;
    color: black;
    background-color: transparent;
  }
}

.mission-button {
  padding: 20px;
  /* background-color: #083958;*/
  cursor: pointer;
  width: 50%;
  position: relative;
  margin-top: 20px;
  font-size: 20px;
  text-align: center;
}

.mission {
  letter-spacing: 0px;
  -webkit-transition: all 1s ease;
  -moz-transition: all 1s ease;
  -o-transition: all 1s ease;
  transition: all 1s ease;
  cursor: pointer;
  animation: changeColor 2s forwards;
}

.mission-button:hover .mission {
  letter-spacing: 5px !important;
}

.mission-button:hover::before {
  width: 32%;
  border-left-width: 200px;
  border-right-width: 200px;
  height: 1px;
  top: 30px;
}

<div class="mission-button"><span class="mission">view our mission</span></div>

Or wrap the text in another container and specify the style on that container:

.mission-button:hover .text-spacing{
    letter-spacing: 5px;    
}

<div class="mission-button">
    <span class="mission">
        <div class="text-spacing">view our mission</div>
    </span>
</div>

.mission-button::before {
    content:'';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    transition: all 1s;
    border-left-width: 2px;
    border-right-width: 2px;
    border-left-style: solid;
    border-right-style: solid;
    background-color: transparent;
    border-color: black; 
    animation: borderOnLoad 2s forwards;
}

@keyframes changeColor {
    0% {
        letter-spacing: 0px;
        color: white;
    }
    100% {
        letter-spacing: 2px;
        color: black;
    }
}

@keyframes borderOnLoad {
    0% {
        width: 100%;
        border-left-width: 3px;
        border-right-width: 3px;
        height: 100%;   
        top: 0;
        color: white;
        background-color: black;
    }
    50% {
        width: 200%;    
        left: -150px;
        border-left-width: 3px; 
        border-right-width: 3px;    
        height: 100%;   
        top: 0;
        color: white;
    } 
    100% {
        width: 65%;
        left: -150px;
        border-left-width: 200px;
        border-right-width: 200px;  
        height: 1px;
        top: 30px;
        color: black;    
        background-color: transparent;
    }
}

.mission-button {
    padding: 20px;
    /* background-color: #083958;*/
    cursor: pointer;
    width: 50%;
    position: relative;
    margin-top: 20px;   
    font-size: 20px;
    text-align: center;
}

.mission {
    letter-spacing: 0px;    
    -webkit-transition: all 1s ease;    
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
    cursor: pointer;
    animation: changeColor 2s forwards;
}   

.mission-button:hover .text-spacing{
    letter-spacing: 5px;    
}

.mission-button:hover::before {
    width: 32%;
    border-left-width: 200px;
    border-right-width: 200px;  
    height: 1px;
    top: 30px;
}

<div class="mission-button">
    <span class="mission">
        <div class="text-spacing">view our mission</div>
    </span>
</div>

Answered By - SyndRain