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

/* colors scheme */

:root{
  --bg-color : #F9F7F7;
  --primary-color : #112D4E;
  --secondary-color : #DBE2EF;
  --focus-color : #3F72AF;
  --plain-text-color : #000;
  --border-color : #2B3040;
}

body{
  background-color: var(--bg-color);
}

.todo-list-container{
  min-height: 10vh;
  max-width: 940px;
  padding : 0 30px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  flex-direction: column;
  gap: 20px;
}

header{
  padding: 1em;
  margin-top: 50px;
  color: var(--primary-color);
  font-family: Verdana, Geneva, Tahoma, sans-serif;
  font-size: clamp(1.1rem, 4vw, 2.7rem);
}
h1{
  border-right: solid .1em #303030;
  white-space: nowrap;
  overflow: hidden;
  animation: typing 3.5s steps(30, end), blink-caret .5s step-end infinite;
}

@keyframes typing {
  from{
    width: 0;
  }
  to{
    width: 100%;
  }
}

@keyframes blink-caret{
  from, to{
    border-color: transparent;
  }
  50%{
    border-color: #303030;
  }
}

.todo-label{
  display: inherit;
  align-items: center;
  width: clamp(300px, 100%, 800px);
  height: 50px;
}

#todo-input::placeholder{
  color: #808692;
}
#todo-input{
  text-indent: 10px;
  width: 100%;
  height: 100%;
  border: solid 1px var(--border-color);
  outline: none;
  background-color: var(--secondary-color);
  color: var(--plain-text-color);
  font-family: monospace;
  font-size: clamp(.8rem, 2vw, 1.05rem);
  overflow: none;
  transition: border 100ms ease;
}
#todo-input:focus{
  border-color: var(--focus-color);
}

#todo-add{
  border: none;
  border: solid 1px var(--border-color);
  background-color: var(--secondary-color);
  width: 60px;
  height: 50px;
  cursor: pointer;
  transition: button 100ms ease ;
}
#todo-add:focus{
  border-color: #596A95;
}

.todo-list{
  display: grid;
  place-content: center;
  width: 100%;
  grid-template-columns: repeat(auto-fill, 390px);
  grid-auto-flow: dense;
  gap: 10px;
}

.todo-item{
  border: solid 5px var(--border-color);
  padding: 1em;
  display: flex;
  align-items: center;
  transition: all .7s ease;
  transition-behavior: allow-discrete;
}

.todo-item.delete{
  transform: translateX(50px);
  display: none;
  opacity: 0;
  pointer-events: none;
}

.todo-item p{
  flex-shrink: 25;
  font-family: monospace;
  font-size: 1.05rem;
  margin-left: .4em;
  word-break: break-all;
}

.todo-item p.check{
  text-decoration: line-through;
  color: #808692;
}

.checkbox{
  width: 35px;
  height: 35px;
  position: relative;
}
.checkbox input{
  width: 100%;
  height: 100%;
  position: absolute;
  opacity: 0;
}

.checkbox span{
  display: block;
  width: 100%;
  height: 100%;
  position: absolute;
  border: solid 3px var(--border-color);
  border-radius: 5px;
  cursor: pointer;
}

.checkbox span::after{
  content: '';
  position: absolute;
  bottom: 9px;
  left: 10px;
  width: 0px;
  height: 0px;
  border: solid var(--primary-color);

  border-width: 0 5px 5px 0;
  transform: rotate(45deg);
  opacity: 0;
  transition: all .2s ease;
}

.checkbox input:checked ~ span::after{
   width: 15px;
   height: 30px;
   opacity: 1;
}

#todo-remove{
   margin-left: auto;
   border: none;
   background: none;
   cursor: pointer;
}
@media (max-width : 768px){
  .todo-list-container{
    padding: 0 14px;
  }
  .todo-list{
    grid-template-columns: repeat(auto-fill, 290px);
  }
}