Why does padding lead to jumpy animation?












-1















Why does the ::before pseudo element jump during a height transition when I apply top and bottom padding to its parent?






a {
font-size: 2em;
font-family: sans-serif;
text-transform: uppercase;
color: #fff;
text-decoration: none;
position: relative;
/* Removing this padding resolves the animation issue, but why? */
padding: 1em;
}

a::before {
content: "";
width: 0.06em;
height: 0%;
position: absolute;
background: #fff;
left: 0;
transition: height 0.25s linear;
}

a:hover::before {
height: 100%;
bottom: 0;
}

.container {
background: #3a3a3a;
height: 100%;
display: flex;
padding-top: 1em;
justify-content: center;
align-items: flex-start;
}

body,
html {
height: 100%;
margin: 0;
}

<div class="container">
<a href="#">Hover Me</a>
</div>












share|improve this question





























    -1















    Why does the ::before pseudo element jump during a height transition when I apply top and bottom padding to its parent?






    a {
    font-size: 2em;
    font-family: sans-serif;
    text-transform: uppercase;
    color: #fff;
    text-decoration: none;
    position: relative;
    /* Removing this padding resolves the animation issue, but why? */
    padding: 1em;
    }

    a::before {
    content: "";
    width: 0.06em;
    height: 0%;
    position: absolute;
    background: #fff;
    left: 0;
    transition: height 0.25s linear;
    }

    a:hover::before {
    height: 100%;
    bottom: 0;
    }

    .container {
    background: #3a3a3a;
    height: 100%;
    display: flex;
    padding-top: 1em;
    justify-content: center;
    align-items: flex-start;
    }

    body,
    html {
    height: 100%;
    margin: 0;
    }

    <div class="container">
    <a href="#">Hover Me</a>
    </div>












    share|improve this question



























      -1












      -1








      -1








      Why does the ::before pseudo element jump during a height transition when I apply top and bottom padding to its parent?






      a {
      font-size: 2em;
      font-family: sans-serif;
      text-transform: uppercase;
      color: #fff;
      text-decoration: none;
      position: relative;
      /* Removing this padding resolves the animation issue, but why? */
      padding: 1em;
      }

      a::before {
      content: "";
      width: 0.06em;
      height: 0%;
      position: absolute;
      background: #fff;
      left: 0;
      transition: height 0.25s linear;
      }

      a:hover::before {
      height: 100%;
      bottom: 0;
      }

      .container {
      background: #3a3a3a;
      height: 100%;
      display: flex;
      padding-top: 1em;
      justify-content: center;
      align-items: flex-start;
      }

      body,
      html {
      height: 100%;
      margin: 0;
      }

      <div class="container">
      <a href="#">Hover Me</a>
      </div>












      share|improve this question
















      Why does the ::before pseudo element jump during a height transition when I apply top and bottom padding to its parent?






      a {
      font-size: 2em;
      font-family: sans-serif;
      text-transform: uppercase;
      color: #fff;
      text-decoration: none;
      position: relative;
      /* Removing this padding resolves the animation issue, but why? */
      padding: 1em;
      }

      a::before {
      content: "";
      width: 0.06em;
      height: 0%;
      position: absolute;
      background: #fff;
      left: 0;
      transition: height 0.25s linear;
      }

      a:hover::before {
      height: 100%;
      bottom: 0;
      }

      .container {
      background: #3a3a3a;
      height: 100%;
      display: flex;
      padding-top: 1em;
      justify-content: center;
      align-items: flex-start;
      }

      body,
      html {
      height: 100%;
      margin: 0;
      }

      <div class="container">
      <a href="#">Hover Me</a>
      </div>








      a {
      font-size: 2em;
      font-family: sans-serif;
      text-transform: uppercase;
      color: #fff;
      text-decoration: none;
      position: relative;
      /* Removing this padding resolves the animation issue, but why? */
      padding: 1em;
      }

      a::before {
      content: "";
      width: 0.06em;
      height: 0%;
      position: absolute;
      background: #fff;
      left: 0;
      transition: height 0.25s linear;
      }

      a:hover::before {
      height: 100%;
      bottom: 0;
      }

      .container {
      background: #3a3a3a;
      height: 100%;
      display: flex;
      padding-top: 1em;
      justify-content: center;
      align-items: flex-start;
      }

      body,
      html {
      height: 100%;
      margin: 0;
      }

      <div class="container">
      <a href="#">Hover Me</a>
      </div>





      a {
      font-size: 2em;
      font-family: sans-serif;
      text-transform: uppercase;
      color: #fff;
      text-decoration: none;
      position: relative;
      /* Removing this padding resolves the animation issue, but why? */
      padding: 1em;
      }

      a::before {
      content: "";
      width: 0.06em;
      height: 0%;
      position: absolute;
      background: #fff;
      left: 0;
      transition: height 0.25s linear;
      }

      a:hover::before {
      height: 100%;
      bottom: 0;
      }

      .container {
      background: #3a3a3a;
      height: 100%;
      display: flex;
      padding-top: 1em;
      justify-content: center;
      align-items: flex-start;
      }

      body,
      html {
      height: 100%;
      margin: 0;
      }

      <div class="container">
      <a href="#">Hover Me</a>
      </div>






      html css






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      share|improve this question













      share|improve this question




      share|improve this question








      edited Nov 21 '18 at 13:06









      jnuK

      1,5401425




      1,5401425










      asked Nov 21 '18 at 11:16









      JenyoinJenyoin

      689




      689
























          3 Answers
          3






          active

          oldest

          votes


















          1














          If you have padding on an element, then apply position absolute on one of it's children the padding amount will be added as an offset to that child element.



          Say you have padding-top:10px;, it'll become top:10px, i think some browsers do rest this.



          DEMO






          *,
          *:before,
          *:after {
          margin: 0;
          padding: 0;
          box-sizing: border-box;
          }

          .test {
          width: 100px;
          height: 100px;
          padding-top: 15px;
          border: 5px solid red;
          }

          .test>div {
          height: 50px;
          width: 50px;
          border: 5px solid red;
          }

          .test:hover>div {
          position: absolute;
          /* uncomment this line to see it */
          /* top: 0; */
          }

          <div class="test">
          <div></div>
          </div>







          Now to fix your issue.






          a {
          font-size: 2em;
          font-family: sans-serif;
          text-transform: uppercase;
          color: #fff;
          text-decoration: none;
          position: relative;
          padding: 1em;
          }

          a::before {
          content: "";
          width: 0.06em;
          height: 0%;
          position: absolute;
          background: #fff;
          left: 0;
          /* rest the top here */
          top: 0;
          transition: height 0.25s linear;
          }

          a:hover::before {
          height: 100%;
          bottom: 0;
          /* unsetting the top because top:0 bottom:0; is full heiht which will prevent the animation the way you want it*/
          /* unsetting the top and not the bottom so it goes upward */
          top: unset;
          }

          .container {
          background: #3a3a3a;
          height: 100%;
          display: flex;
          padding-top: 1em;
          justify-content: center;
          align-items: flex-start;
          }

          body,
          html {
          height: 100%;
          margin: 0;
          }

          <div class="container">
          <a href="#">Hover Me</a>
          </div>








          share|improve this answer

































            1














            Move the bottom: 0 rule from a:hover::before to the a::before rule set.



            In general, try to minimize amount of rules in selectors like :hover -- whenever a "hover" rule set applies, the chances of things jumping or moving because of inability to mentally calculate how the layout engine will render things, is ever higher the more properties are overriden. You don't need bottom: 0 there, but if you need to align to the bottom, set it on the same rule set without the :hover to it, i.e. the a::before -- it will be inherited anyway by the element in the "hover" state. If you on the other hand only desire the height of an element to transition as you hover over, then that's the only rule that should be set there, should it not?






            share|improve this answer


























            • I like the advice of minimizing :hover rules and the like. However, in this case I am intentionally changing the anchor point to get the desired animation.

              – Jenyoin
              Nov 21 '18 at 13:03











            • Am I to understand you want your white line to spread out from the vertical center of the following block?

              – amn
              Nov 21 '18 at 13:28



















            0














            The issue is your before content is not aligned properly.
            Here is the solution...






            a {
            font-size: 2em;
            font-family: sans-serif;
            text-transform: uppercase;
            color: #fff;
            text-decoration: none;
            position: relative;
            /* Removing this padding resolves the animation issue, but why? */
            padding: 1em;
            }

            a::before {
            content: "";
            width: 0.06em;
            height: 0%;
            position: absolute;
            background: #fff;
            bottom:0;
            left: 0;
            transition: height 0.25s linear;
            }

            a:hover::before {
            top:0;
            height: 100%;
            }

            .container {
            background: #3a3a3a;
            height: 100%;
            display: flex;
            padding-top: 1em;
            justify-content: center;
            align-items: flex-start;
            }

            body,
            html {
            height: 100%;
            margin: 0;
            }

            <div class="container">
            <a href="#">Hover Me</a>
            </div>








            share|improve this answer


























            • Hi Jeet! That does indeed make the animation not jump, but I would like it to grow upwards and then shrink upwards as in my example. :-)

              – Jenyoin
              Nov 21 '18 at 11:22











            • I have updated the code. please check

              – OneJeet
              Nov 21 '18 at 11:39











            • This was the animation I created first. But I am trying to do the reverse animation: Grow and shrink upwards, not grow and shrink downwards. Also, I am trying to learn why it happens more so than fixing it.

              – Jenyoin
              Nov 21 '18 at 11:46








            • 1





              This is happening because when you remove top:0; from a::before content, the absolute position doesn't let is align. check developer tool with hover position on to see where it is aligned.

              – OneJeet
              Nov 21 '18 at 11:55











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            3 Answers
            3






            active

            oldest

            votes








            3 Answers
            3






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            1














            If you have padding on an element, then apply position absolute on one of it's children the padding amount will be added as an offset to that child element.



            Say you have padding-top:10px;, it'll become top:10px, i think some browsers do rest this.



            DEMO






            *,
            *:before,
            *:after {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            }

            .test {
            width: 100px;
            height: 100px;
            padding-top: 15px;
            border: 5px solid red;
            }

            .test>div {
            height: 50px;
            width: 50px;
            border: 5px solid red;
            }

            .test:hover>div {
            position: absolute;
            /* uncomment this line to see it */
            /* top: 0; */
            }

            <div class="test">
            <div></div>
            </div>







            Now to fix your issue.






            a {
            font-size: 2em;
            font-family: sans-serif;
            text-transform: uppercase;
            color: #fff;
            text-decoration: none;
            position: relative;
            padding: 1em;
            }

            a::before {
            content: "";
            width: 0.06em;
            height: 0%;
            position: absolute;
            background: #fff;
            left: 0;
            /* rest the top here */
            top: 0;
            transition: height 0.25s linear;
            }

            a:hover::before {
            height: 100%;
            bottom: 0;
            /* unsetting the top because top:0 bottom:0; is full heiht which will prevent the animation the way you want it*/
            /* unsetting the top and not the bottom so it goes upward */
            top: unset;
            }

            .container {
            background: #3a3a3a;
            height: 100%;
            display: flex;
            padding-top: 1em;
            justify-content: center;
            align-items: flex-start;
            }

            body,
            html {
            height: 100%;
            margin: 0;
            }

            <div class="container">
            <a href="#">Hover Me</a>
            </div>








            share|improve this answer






























              1














              If you have padding on an element, then apply position absolute on one of it's children the padding amount will be added as an offset to that child element.



              Say you have padding-top:10px;, it'll become top:10px, i think some browsers do rest this.



              DEMO






              *,
              *:before,
              *:after {
              margin: 0;
              padding: 0;
              box-sizing: border-box;
              }

              .test {
              width: 100px;
              height: 100px;
              padding-top: 15px;
              border: 5px solid red;
              }

              .test>div {
              height: 50px;
              width: 50px;
              border: 5px solid red;
              }

              .test:hover>div {
              position: absolute;
              /* uncomment this line to see it */
              /* top: 0; */
              }

              <div class="test">
              <div></div>
              </div>







              Now to fix your issue.






              a {
              font-size: 2em;
              font-family: sans-serif;
              text-transform: uppercase;
              color: #fff;
              text-decoration: none;
              position: relative;
              padding: 1em;
              }

              a::before {
              content: "";
              width: 0.06em;
              height: 0%;
              position: absolute;
              background: #fff;
              left: 0;
              /* rest the top here */
              top: 0;
              transition: height 0.25s linear;
              }

              a:hover::before {
              height: 100%;
              bottom: 0;
              /* unsetting the top because top:0 bottom:0; is full heiht which will prevent the animation the way you want it*/
              /* unsetting the top and not the bottom so it goes upward */
              top: unset;
              }

              .container {
              background: #3a3a3a;
              height: 100%;
              display: flex;
              padding-top: 1em;
              justify-content: center;
              align-items: flex-start;
              }

              body,
              html {
              height: 100%;
              margin: 0;
              }

              <div class="container">
              <a href="#">Hover Me</a>
              </div>








              share|improve this answer




























                1












                1








                1







                If you have padding on an element, then apply position absolute on one of it's children the padding amount will be added as an offset to that child element.



                Say you have padding-top:10px;, it'll become top:10px, i think some browsers do rest this.



                DEMO






                *,
                *:before,
                *:after {
                margin: 0;
                padding: 0;
                box-sizing: border-box;
                }

                .test {
                width: 100px;
                height: 100px;
                padding-top: 15px;
                border: 5px solid red;
                }

                .test>div {
                height: 50px;
                width: 50px;
                border: 5px solid red;
                }

                .test:hover>div {
                position: absolute;
                /* uncomment this line to see it */
                /* top: 0; */
                }

                <div class="test">
                <div></div>
                </div>







                Now to fix your issue.






                a {
                font-size: 2em;
                font-family: sans-serif;
                text-transform: uppercase;
                color: #fff;
                text-decoration: none;
                position: relative;
                padding: 1em;
                }

                a::before {
                content: "";
                width: 0.06em;
                height: 0%;
                position: absolute;
                background: #fff;
                left: 0;
                /* rest the top here */
                top: 0;
                transition: height 0.25s linear;
                }

                a:hover::before {
                height: 100%;
                bottom: 0;
                /* unsetting the top because top:0 bottom:0; is full heiht which will prevent the animation the way you want it*/
                /* unsetting the top and not the bottom so it goes upward */
                top: unset;
                }

                .container {
                background: #3a3a3a;
                height: 100%;
                display: flex;
                padding-top: 1em;
                justify-content: center;
                align-items: flex-start;
                }

                body,
                html {
                height: 100%;
                margin: 0;
                }

                <div class="container">
                <a href="#">Hover Me</a>
                </div>








                share|improve this answer















                If you have padding on an element, then apply position absolute on one of it's children the padding amount will be added as an offset to that child element.



                Say you have padding-top:10px;, it'll become top:10px, i think some browsers do rest this.



                DEMO






                *,
                *:before,
                *:after {
                margin: 0;
                padding: 0;
                box-sizing: border-box;
                }

                .test {
                width: 100px;
                height: 100px;
                padding-top: 15px;
                border: 5px solid red;
                }

                .test>div {
                height: 50px;
                width: 50px;
                border: 5px solid red;
                }

                .test:hover>div {
                position: absolute;
                /* uncomment this line to see it */
                /* top: 0; */
                }

                <div class="test">
                <div></div>
                </div>







                Now to fix your issue.






                a {
                font-size: 2em;
                font-family: sans-serif;
                text-transform: uppercase;
                color: #fff;
                text-decoration: none;
                position: relative;
                padding: 1em;
                }

                a::before {
                content: "";
                width: 0.06em;
                height: 0%;
                position: absolute;
                background: #fff;
                left: 0;
                /* rest the top here */
                top: 0;
                transition: height 0.25s linear;
                }

                a:hover::before {
                height: 100%;
                bottom: 0;
                /* unsetting the top because top:0 bottom:0; is full heiht which will prevent the animation the way you want it*/
                /* unsetting the top and not the bottom so it goes upward */
                top: unset;
                }

                .container {
                background: #3a3a3a;
                height: 100%;
                display: flex;
                padding-top: 1em;
                justify-content: center;
                align-items: flex-start;
                }

                body,
                html {
                height: 100%;
                margin: 0;
                }

                <div class="container">
                <a href="#">Hover Me</a>
                </div>








                *,
                *:before,
                *:after {
                margin: 0;
                padding: 0;
                box-sizing: border-box;
                }

                .test {
                width: 100px;
                height: 100px;
                padding-top: 15px;
                border: 5px solid red;
                }

                .test>div {
                height: 50px;
                width: 50px;
                border: 5px solid red;
                }

                .test:hover>div {
                position: absolute;
                /* uncomment this line to see it */
                /* top: 0; */
                }

                <div class="test">
                <div></div>
                </div>





                *,
                *:before,
                *:after {
                margin: 0;
                padding: 0;
                box-sizing: border-box;
                }

                .test {
                width: 100px;
                height: 100px;
                padding-top: 15px;
                border: 5px solid red;
                }

                .test>div {
                height: 50px;
                width: 50px;
                border: 5px solid red;
                }

                .test:hover>div {
                position: absolute;
                /* uncomment this line to see it */
                /* top: 0; */
                }

                <div class="test">
                <div></div>
                </div>





                a {
                font-size: 2em;
                font-family: sans-serif;
                text-transform: uppercase;
                color: #fff;
                text-decoration: none;
                position: relative;
                padding: 1em;
                }

                a::before {
                content: "";
                width: 0.06em;
                height: 0%;
                position: absolute;
                background: #fff;
                left: 0;
                /* rest the top here */
                top: 0;
                transition: height 0.25s linear;
                }

                a:hover::before {
                height: 100%;
                bottom: 0;
                /* unsetting the top because top:0 bottom:0; is full heiht which will prevent the animation the way you want it*/
                /* unsetting the top and not the bottom so it goes upward */
                top: unset;
                }

                .container {
                background: #3a3a3a;
                height: 100%;
                display: flex;
                padding-top: 1em;
                justify-content: center;
                align-items: flex-start;
                }

                body,
                html {
                height: 100%;
                margin: 0;
                }

                <div class="container">
                <a href="#">Hover Me</a>
                </div>





                a {
                font-size: 2em;
                font-family: sans-serif;
                text-transform: uppercase;
                color: #fff;
                text-decoration: none;
                position: relative;
                padding: 1em;
                }

                a::before {
                content: "";
                width: 0.06em;
                height: 0%;
                position: absolute;
                background: #fff;
                left: 0;
                /* rest the top here */
                top: 0;
                transition: height 0.25s linear;
                }

                a:hover::before {
                height: 100%;
                bottom: 0;
                /* unsetting the top because top:0 bottom:0; is full heiht which will prevent the animation the way you want it*/
                /* unsetting the top and not the bottom so it goes upward */
                top: unset;
                }

                .container {
                background: #3a3a3a;
                height: 100%;
                display: flex;
                padding-top: 1em;
                justify-content: center;
                align-items: flex-start;
                }

                body,
                html {
                height: 100%;
                margin: 0;
                }

                <div class="container">
                <a href="#">Hover Me</a>
                </div>






                share|improve this answer














                share|improve this answer



                share|improve this answer








                edited Nov 21 '18 at 12:43

























                answered Nov 21 '18 at 12:19









                Zohir SalakZohir Salak

                2,5031414




                2,5031414

























                    1














                    Move the bottom: 0 rule from a:hover::before to the a::before rule set.



                    In general, try to minimize amount of rules in selectors like :hover -- whenever a "hover" rule set applies, the chances of things jumping or moving because of inability to mentally calculate how the layout engine will render things, is ever higher the more properties are overriden. You don't need bottom: 0 there, but if you need to align to the bottom, set it on the same rule set without the :hover to it, i.e. the a::before -- it will be inherited anyway by the element in the "hover" state. If you on the other hand only desire the height of an element to transition as you hover over, then that's the only rule that should be set there, should it not?






                    share|improve this answer


























                    • I like the advice of minimizing :hover rules and the like. However, in this case I am intentionally changing the anchor point to get the desired animation.

                      – Jenyoin
                      Nov 21 '18 at 13:03











                    • Am I to understand you want your white line to spread out from the vertical center of the following block?

                      – amn
                      Nov 21 '18 at 13:28
















                    1














                    Move the bottom: 0 rule from a:hover::before to the a::before rule set.



                    In general, try to minimize amount of rules in selectors like :hover -- whenever a "hover" rule set applies, the chances of things jumping or moving because of inability to mentally calculate how the layout engine will render things, is ever higher the more properties are overriden. You don't need bottom: 0 there, but if you need to align to the bottom, set it on the same rule set without the :hover to it, i.e. the a::before -- it will be inherited anyway by the element in the "hover" state. If you on the other hand only desire the height of an element to transition as you hover over, then that's the only rule that should be set there, should it not?






                    share|improve this answer


























                    • I like the advice of minimizing :hover rules and the like. However, in this case I am intentionally changing the anchor point to get the desired animation.

                      – Jenyoin
                      Nov 21 '18 at 13:03











                    • Am I to understand you want your white line to spread out from the vertical center of the following block?

                      – amn
                      Nov 21 '18 at 13:28














                    1












                    1








                    1







                    Move the bottom: 0 rule from a:hover::before to the a::before rule set.



                    In general, try to minimize amount of rules in selectors like :hover -- whenever a "hover" rule set applies, the chances of things jumping or moving because of inability to mentally calculate how the layout engine will render things, is ever higher the more properties are overriden. You don't need bottom: 0 there, but if you need to align to the bottom, set it on the same rule set without the :hover to it, i.e. the a::before -- it will be inherited anyway by the element in the "hover" state. If you on the other hand only desire the height of an element to transition as you hover over, then that's the only rule that should be set there, should it not?






                    share|improve this answer















                    Move the bottom: 0 rule from a:hover::before to the a::before rule set.



                    In general, try to minimize amount of rules in selectors like :hover -- whenever a "hover" rule set applies, the chances of things jumping or moving because of inability to mentally calculate how the layout engine will render things, is ever higher the more properties are overriden. You don't need bottom: 0 there, but if you need to align to the bottom, set it on the same rule set without the :hover to it, i.e. the a::before -- it will be inherited anyway by the element in the "hover" state. If you on the other hand only desire the height of an element to transition as you hover over, then that's the only rule that should be set there, should it not?







                    share|improve this answer














                    share|improve this answer



                    share|improve this answer








                    edited Nov 21 '18 at 13:00

























                    answered Nov 21 '18 at 12:43









                    amnamn

                    3,95553262




                    3,95553262













                    • I like the advice of minimizing :hover rules and the like. However, in this case I am intentionally changing the anchor point to get the desired animation.

                      – Jenyoin
                      Nov 21 '18 at 13:03











                    • Am I to understand you want your white line to spread out from the vertical center of the following block?

                      – amn
                      Nov 21 '18 at 13:28



















                    • I like the advice of minimizing :hover rules and the like. However, in this case I am intentionally changing the anchor point to get the desired animation.

                      – Jenyoin
                      Nov 21 '18 at 13:03











                    • Am I to understand you want your white line to spread out from the vertical center of the following block?

                      – amn
                      Nov 21 '18 at 13:28

















                    I like the advice of minimizing :hover rules and the like. However, in this case I am intentionally changing the anchor point to get the desired animation.

                    – Jenyoin
                    Nov 21 '18 at 13:03





                    I like the advice of minimizing :hover rules and the like. However, in this case I am intentionally changing the anchor point to get the desired animation.

                    – Jenyoin
                    Nov 21 '18 at 13:03













                    Am I to understand you want your white line to spread out from the vertical center of the following block?

                    – amn
                    Nov 21 '18 at 13:28





                    Am I to understand you want your white line to spread out from the vertical center of the following block?

                    – amn
                    Nov 21 '18 at 13:28











                    0














                    The issue is your before content is not aligned properly.
                    Here is the solution...






                    a {
                    font-size: 2em;
                    font-family: sans-serif;
                    text-transform: uppercase;
                    color: #fff;
                    text-decoration: none;
                    position: relative;
                    /* Removing this padding resolves the animation issue, but why? */
                    padding: 1em;
                    }

                    a::before {
                    content: "";
                    width: 0.06em;
                    height: 0%;
                    position: absolute;
                    background: #fff;
                    bottom:0;
                    left: 0;
                    transition: height 0.25s linear;
                    }

                    a:hover::before {
                    top:0;
                    height: 100%;
                    }

                    .container {
                    background: #3a3a3a;
                    height: 100%;
                    display: flex;
                    padding-top: 1em;
                    justify-content: center;
                    align-items: flex-start;
                    }

                    body,
                    html {
                    height: 100%;
                    margin: 0;
                    }

                    <div class="container">
                    <a href="#">Hover Me</a>
                    </div>








                    share|improve this answer


























                    • Hi Jeet! That does indeed make the animation not jump, but I would like it to grow upwards and then shrink upwards as in my example. :-)

                      – Jenyoin
                      Nov 21 '18 at 11:22











                    • I have updated the code. please check

                      – OneJeet
                      Nov 21 '18 at 11:39











                    • This was the animation I created first. But I am trying to do the reverse animation: Grow and shrink upwards, not grow and shrink downwards. Also, I am trying to learn why it happens more so than fixing it.

                      – Jenyoin
                      Nov 21 '18 at 11:46








                    • 1





                      This is happening because when you remove top:0; from a::before content, the absolute position doesn't let is align. check developer tool with hover position on to see where it is aligned.

                      – OneJeet
                      Nov 21 '18 at 11:55
















                    0














                    The issue is your before content is not aligned properly.
                    Here is the solution...






                    a {
                    font-size: 2em;
                    font-family: sans-serif;
                    text-transform: uppercase;
                    color: #fff;
                    text-decoration: none;
                    position: relative;
                    /* Removing this padding resolves the animation issue, but why? */
                    padding: 1em;
                    }

                    a::before {
                    content: "";
                    width: 0.06em;
                    height: 0%;
                    position: absolute;
                    background: #fff;
                    bottom:0;
                    left: 0;
                    transition: height 0.25s linear;
                    }

                    a:hover::before {
                    top:0;
                    height: 100%;
                    }

                    .container {
                    background: #3a3a3a;
                    height: 100%;
                    display: flex;
                    padding-top: 1em;
                    justify-content: center;
                    align-items: flex-start;
                    }

                    body,
                    html {
                    height: 100%;
                    margin: 0;
                    }

                    <div class="container">
                    <a href="#">Hover Me</a>
                    </div>








                    share|improve this answer


























                    • Hi Jeet! That does indeed make the animation not jump, but I would like it to grow upwards and then shrink upwards as in my example. :-)

                      – Jenyoin
                      Nov 21 '18 at 11:22











                    • I have updated the code. please check

                      – OneJeet
                      Nov 21 '18 at 11:39











                    • This was the animation I created first. But I am trying to do the reverse animation: Grow and shrink upwards, not grow and shrink downwards. Also, I am trying to learn why it happens more so than fixing it.

                      – Jenyoin
                      Nov 21 '18 at 11:46








                    • 1





                      This is happening because when you remove top:0; from a::before content, the absolute position doesn't let is align. check developer tool with hover position on to see where it is aligned.

                      – OneJeet
                      Nov 21 '18 at 11:55














                    0












                    0








                    0







                    The issue is your before content is not aligned properly.
                    Here is the solution...






                    a {
                    font-size: 2em;
                    font-family: sans-serif;
                    text-transform: uppercase;
                    color: #fff;
                    text-decoration: none;
                    position: relative;
                    /* Removing this padding resolves the animation issue, but why? */
                    padding: 1em;
                    }

                    a::before {
                    content: "";
                    width: 0.06em;
                    height: 0%;
                    position: absolute;
                    background: #fff;
                    bottom:0;
                    left: 0;
                    transition: height 0.25s linear;
                    }

                    a:hover::before {
                    top:0;
                    height: 100%;
                    }

                    .container {
                    background: #3a3a3a;
                    height: 100%;
                    display: flex;
                    padding-top: 1em;
                    justify-content: center;
                    align-items: flex-start;
                    }

                    body,
                    html {
                    height: 100%;
                    margin: 0;
                    }

                    <div class="container">
                    <a href="#">Hover Me</a>
                    </div>








                    share|improve this answer















                    The issue is your before content is not aligned properly.
                    Here is the solution...






                    a {
                    font-size: 2em;
                    font-family: sans-serif;
                    text-transform: uppercase;
                    color: #fff;
                    text-decoration: none;
                    position: relative;
                    /* Removing this padding resolves the animation issue, but why? */
                    padding: 1em;
                    }

                    a::before {
                    content: "";
                    width: 0.06em;
                    height: 0%;
                    position: absolute;
                    background: #fff;
                    bottom:0;
                    left: 0;
                    transition: height 0.25s linear;
                    }

                    a:hover::before {
                    top:0;
                    height: 100%;
                    }

                    .container {
                    background: #3a3a3a;
                    height: 100%;
                    display: flex;
                    padding-top: 1em;
                    justify-content: center;
                    align-items: flex-start;
                    }

                    body,
                    html {
                    height: 100%;
                    margin: 0;
                    }

                    <div class="container">
                    <a href="#">Hover Me</a>
                    </div>








                    a {
                    font-size: 2em;
                    font-family: sans-serif;
                    text-transform: uppercase;
                    color: #fff;
                    text-decoration: none;
                    position: relative;
                    /* Removing this padding resolves the animation issue, but why? */
                    padding: 1em;
                    }

                    a::before {
                    content: "";
                    width: 0.06em;
                    height: 0%;
                    position: absolute;
                    background: #fff;
                    bottom:0;
                    left: 0;
                    transition: height 0.25s linear;
                    }

                    a:hover::before {
                    top:0;
                    height: 100%;
                    }

                    .container {
                    background: #3a3a3a;
                    height: 100%;
                    display: flex;
                    padding-top: 1em;
                    justify-content: center;
                    align-items: flex-start;
                    }

                    body,
                    html {
                    height: 100%;
                    margin: 0;
                    }

                    <div class="container">
                    <a href="#">Hover Me</a>
                    </div>





                    a {
                    font-size: 2em;
                    font-family: sans-serif;
                    text-transform: uppercase;
                    color: #fff;
                    text-decoration: none;
                    position: relative;
                    /* Removing this padding resolves the animation issue, but why? */
                    padding: 1em;
                    }

                    a::before {
                    content: "";
                    width: 0.06em;
                    height: 0%;
                    position: absolute;
                    background: #fff;
                    bottom:0;
                    left: 0;
                    transition: height 0.25s linear;
                    }

                    a:hover::before {
                    top:0;
                    height: 100%;
                    }

                    .container {
                    background: #3a3a3a;
                    height: 100%;
                    display: flex;
                    padding-top: 1em;
                    justify-content: center;
                    align-items: flex-start;
                    }

                    body,
                    html {
                    height: 100%;
                    margin: 0;
                    }

                    <div class="container">
                    <a href="#">Hover Me</a>
                    </div>






                    share|improve this answer














                    share|improve this answer



                    share|improve this answer








                    edited Nov 21 '18 at 11:39

























                    answered Nov 21 '18 at 11:19









                    OneJeetOneJeet

                    962310




                    962310













                    • Hi Jeet! That does indeed make the animation not jump, but I would like it to grow upwards and then shrink upwards as in my example. :-)

                      – Jenyoin
                      Nov 21 '18 at 11:22











                    • I have updated the code. please check

                      – OneJeet
                      Nov 21 '18 at 11:39











                    • This was the animation I created first. But I am trying to do the reverse animation: Grow and shrink upwards, not grow and shrink downwards. Also, I am trying to learn why it happens more so than fixing it.

                      – Jenyoin
                      Nov 21 '18 at 11:46








                    • 1





                      This is happening because when you remove top:0; from a::before content, the absolute position doesn't let is align. check developer tool with hover position on to see where it is aligned.

                      – OneJeet
                      Nov 21 '18 at 11:55



















                    • Hi Jeet! That does indeed make the animation not jump, but I would like it to grow upwards and then shrink upwards as in my example. :-)

                      – Jenyoin
                      Nov 21 '18 at 11:22











                    • I have updated the code. please check

                      – OneJeet
                      Nov 21 '18 at 11:39











                    • This was the animation I created first. But I am trying to do the reverse animation: Grow and shrink upwards, not grow and shrink downwards. Also, I am trying to learn why it happens more so than fixing it.

                      – Jenyoin
                      Nov 21 '18 at 11:46








                    • 1





                      This is happening because when you remove top:0; from a::before content, the absolute position doesn't let is align. check developer tool with hover position on to see where it is aligned.

                      – OneJeet
                      Nov 21 '18 at 11:55

















                    Hi Jeet! That does indeed make the animation not jump, but I would like it to grow upwards and then shrink upwards as in my example. :-)

                    – Jenyoin
                    Nov 21 '18 at 11:22





                    Hi Jeet! That does indeed make the animation not jump, but I would like it to grow upwards and then shrink upwards as in my example. :-)

                    – Jenyoin
                    Nov 21 '18 at 11:22













                    I have updated the code. please check

                    – OneJeet
                    Nov 21 '18 at 11:39





                    I have updated the code. please check

                    – OneJeet
                    Nov 21 '18 at 11:39













                    This was the animation I created first. But I am trying to do the reverse animation: Grow and shrink upwards, not grow and shrink downwards. Also, I am trying to learn why it happens more so than fixing it.

                    – Jenyoin
                    Nov 21 '18 at 11:46







                    This was the animation I created first. But I am trying to do the reverse animation: Grow and shrink upwards, not grow and shrink downwards. Also, I am trying to learn why it happens more so than fixing it.

                    – Jenyoin
                    Nov 21 '18 at 11:46






                    1




                    1





                    This is happening because when you remove top:0; from a::before content, the absolute position doesn't let is align. check developer tool with hover position on to see where it is aligned.

                    – OneJeet
                    Nov 21 '18 at 11:55





                    This is happening because when you remove top:0; from a::before content, the absolute position doesn't let is align. check developer tool with hover position on to see where it is aligned.

                    – OneJeet
                    Nov 21 '18 at 11:55


















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