@import url("https://fonts.googleapis.com/css2?family=Poppins:ital,wght@0,100;0,200;0,300;0,400;0,500;0,600;0,700;0,800;0,900;1,100;1,200;1,300;1,400;1,500;1,600;1,700;1,800;1,900&display=swap");

* {
  margin: 0;
  padding: 0;
  font-family: "Poppins", sans-serif;
}

/* Default Theme Variables */

:root {
  --bg-color: hsl(222, 26%, 31%);
  --calculatorBtn-bg-color: hsl(223, 31%, 20%);
  --text-color: #ffffff;
  --display-bg-color: hsl(224, 36%, 15%);
   --display-text-color: hsl(0, 0%, 100%); 
  --button-bg-color: #d1cccc ;
  --button-hover-bg-color: hsl(0, 27%, 96%);
  --box-shadow: 0px 4px 0px #636262;
  --button-text-color: hsl(221, 14%, 31%);
  --reset-bg-color: hsl(225, 21%, 49%);
  --reset-hover-bg-color: hsl(225, 37%, 64%);
  --box-shadow-color: 0px 4px 0px hsl(224, 28%, 35%);
  --equals-bg-color: hsl(6, 63%, 50%);
  --equals-hover-bg-color: hsl(6, 46%, 53%);
  --equals-box-shadow: 0px 4px 0px hsl(6, 70%, 34%);
}

/* Theme 2 Variables */

body.theme2 {
  --bg-color: hsl(0, 0%, 90%);
  --text-color: hsl(60, 10%, 19%);
  --display-bg-color: hsl(0, 0%, 93%);
  --calculatorBtn-bg-color: hsl(0, 5%, 81%);
  --inputBox-text-colr: hsl(60, 10%, 19%);
  --display-text-color: hsl(60, 10%, 19%);
  --button-bg-color: hsl(0, 0%, 93%);
  --box-shadow: 0px 4px 0px hsl(35, 11%, 61%);
  --button-text-color: hsl(60, 10%, 19%);
  --button-hover-bg-color: hsl(0, 100%, 100%);
  --reset-bg-color: hsl(185, 42%, 37%);
  --box-shadow-color: 0px 4px 0px hsl(185, 58%, 25%);
  --reset-bg-color: hsl(185, 42%, 37%);
  --reset-text-color: #fff;
  --reset-hover-bg-color: hsl(187, 39%, 53%);
  --del-bg-color: hsl(185, 42%, 37%);
  --equals-bg-color: hsl(25, 98%, 40%);
  --equals-text-color:#fff;
  --equals-hover-bg-color: hsl(25, 78%, 49%);
  --equals-box-shadow: 0px 4px 0px hsl(25, 99%, 27%);
}

/* Theme 3 Variables */

body.theme3 {
  --bg-color: hsl(268, 75%, 9%);
  --calculatorBtn-bg-color: hsl(268, 71%, 15%);
  --text-color: hsl(52, 100%, 62%);
  --display-bg-color: hsl(268, 71%, 15%);
  --display-text-color: hsl(52, 100%, 62%);
  --button-bg-color: hsl(268, 47%, 21%);
  --button-hover-bg-color: hsl(267, 56%, 49%);
  --box-shadow: 0px 4px 0px hsl(290, 70%, 36%);
  --button-text-color: hsl(52, 100%, 62%);
  --reset-bg-color: hsl(281, 89%, 26%);
  --reset-hover-bg-color: hsl(283, 64%, 44%);
  --reset-text-color:hsl(0, 0%, 100%);
  --box-shadow-color: 0px 4px 0px hsl(285, 91%, 52%);
  --del-bg-color: hsl(281, 89%, 26%);
  --equals-bg-color: hsl(176, 100%, 44%);
  --equals-text-color: #000;
  --equals-hover-bg-color:  hsl(177, 78%, 69%);
  --equals-box-shadow: 0px 4px 0px hsl(177, 92%, 70%);
}

/* Global Styles */

body {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  margin-top: 7rem;
  gap: 30px;
  background-color: var(--bg-color);
  color: var(--text-color);
}

/* Calculator Styles */

.calculator {
  border-radius: 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-direction: column;
  display: grid;
  grid-template-columns: 1fr;
  grid-gap: 2rem;
}

/* Header Styles */

.header {
  display: grid;
  grid-template-columns: 5rem auto 5rem;
  border-radius: 10px;
  color: var(--text-color);
}

.header .title {
  font-size: 1rem;
  font-weight: 800;
  display: flex;
  justify-content: end;
  align-items: end;
}

.theme-controls {
  display: flex;
  align-items: center;
  flex-direction: column;
}

.theme-label {
  font-size: 0.9em;
  letter-spacing: 0.5px;
  font-weight: 600;
  display: flex;
  justify-content: end;
  align-items: end;
}

.theme-options {
  display: flex;
  align-items: start;
  gap: 1rem;
  font-weight: 300;
  color: var(--text-color);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}


/* Toggle Switch Styles */

.toggle-switch {
  position: relative;
  width: 65px;
  height: 25px;
  background-color: var(--calculatorBtn-bg-color);
  border-radius: 16px;
  cursor: pointer;
}

.toggle-knob {
  position: absolute;
  top: 3px;
  left: 1.5px;
  width: 19px;
  height: 19px;
  background-color: var(--equals-bg-color);
  border-radius: 50%;
  transition: transform 0.3s ease;
  cursor: pointer;
}
.toggle-knob:hover{
  background-color: var(--equals-hover-bg-color);
}

/* Knob Positions for Each Theme */
.toggle-switch.theme-1 .toggle-knob {
  transform: translateX(2px);
}

.toggle-switch.theme-2 .toggle-knob {
  transform: translateX(22px);
}

.toggle-switch.theme-3 .toggle-knob {
  transform: translateX(42px);
}

/* Calculator Button Styles */

.calculatorBtn {
  border-radius: 16px;
  padding: 20px;
  background-color: var(--calculatorBtn-bg-color);
  color: var(--text-color);
  box-shadow: var(--bg-color);
}

input {
  width: 490px;
  border: none;
  padding: 24px;
  font-size: 40px;
  font-weight: 700;
  text-align: right;
  cursor: pointer;
  border-radius: 12px;
  background-color: var(--display-bg-color);
  color: var(--display-text-color);
}

input::placeholder {
  color: var(--display-text-color);
}

button {
  border: none;
  width: 90px;
  height: 50px;
  margin: 15px;
  border-radius: 8px;
  font-size: 25px;
  cursor: pointer;
  color: hsl(222, 26%, 31%);
  font-weight: 800;
  background-color: var(--button-bg-color);
  color: var(--button-text-color);
  box-shadow: var(--box-shadow);
}
button:hover{
  background-color: var(--button-hover-bg-color);
}

.equalBtn {
  height: 60px;
  width: 220px;
  background-color: var(--equals-bg-color);
  color: var(--equals-text-color);
  box-shadow: var(--equals-box-shadow);
}
.equalBtn:hover{
  background-color:  var(--equals-hover-bg-color);
}


.resetBtn {
  font-weight: 600;
  width: 220px;
  height: 60px;
  background-color: var(--reset-bg-color);
  color: var(--reset-text-color);
  box-shadow: var(--box-shadow-color);
}
.resetBtn:hover{
  background-color: var(--reset-hover-bg-color);
}

.con {
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.operator {
  font-weight: 600;
  background-color: var(--reset-bg-color);
  color: var(--reset-text-color);
  box-shadow: var(--box-shadow-color);
}
.operator:hover{
  background-color: var(--reset-hover-bg-color)
}


/* General Media Query for Mobile */

@media (max-width: 568px) {
  .calculator{
    display: flex;
    flex-direction: column;
    justify-content: center;
  }
  .calculatorBtn{
    padding: 18px;
  }
  input{
    width: 475px;
  }
   button{
    height: 55px;
    width: 85px;
  }
  .equalBtn, .resetBtn{
    width: 200px;
  }
  .header{
    display: grid;
    grid-template-columns: 2.5rem 20rem 3rem;
    grid-gap: 30px;
   }
   .title{
    padding-left: 2rem;
   }

}
@media (max-width: 546px){
 .calculator{
  display: flex;
  justify-content: center;
  flex-direction: column;
 }
 .calculatorBtn{
  padding: 16px;
 }
 button{
  height: 60px;
  width: 80px;
 }
 .equalBtn, .resetBtn{
  width: 200px;
}
input{
  width: 445px;
}
.header{
  display: grid;
  grid-template-columns: 4rem 17rem 3.5rem;
  grid-gap: 30px;
 }
}

@media (max-width:512px){
  .calculator{
    display: flex;
    justify-content: center;
    flex-direction: column;
   }
   .calculatorBtn{
    padding: 14px;
   }
  
   button{
    height: 65px;
    width: 75px;
   }
   .equalBtn, .resetBtn{
    width: 190px;
  }
  input{
    width: 412px;
  }
  .header{
    display: grid;
    grid-template-columns:  0.5rem 18rem 1rem;
    grid-gap: 30px;
   }
  }
@media (max-width:462px){
  .calculator{
    display: flex;
    justify-content: center;
    flex-direction: column;
   }

   .calculatorBtn{
    padding: 12px;
   }
 
   button{
    height: 70px;
    width: 70px;
   }
   .equalBtn, .resetBtn{
    width: 180px;
  }
  input{
    width: 400px;
  }
  .header{
    display: grid;
    grid-template-columns: 0.5rem 17.5rem 1rem;
    grid-gap: 30px;
   }
  }
@media (max-width:458px){
  .calculator{
    display: flex;
    justify-content: center;
    flex-direction: column;
   }

   .calculatorBtn{
    padding: 10px;
   }
   button{
    height: 75px;
    width: 65px;
   }
   
   .equalBtn, .resetBtn{
    width: 165px;
  }
  input{
    width: 370px;
  }
  .header{
    display: grid;
    grid-template-columns: 0.5rem 15.5rem 1.5rem;
    grid-gap: 30px;
   }
  }

@media (max-width:400px){
  .calculator{
    display: flex;
    justify-content: center;
    flex-direction: column;
   }
   .calculatorBtn{
    padding: 8px;
   }
 
   button{
    height: 80px;
    width: 60px;
   }
   .equalBtn, .resetBtn{
    width: 160px;
  }
  input{
    width: 350px;
  }
  .header{
    display: grid;
    grid-template-columns: 2rem 3rem 5rem;
    grid-gap: 30px;
   }
  }
@media (max-width:418px){
  .calculator{
    display: flex;
    justify-content: center;
    flex-direction: column;
   }
   .calculatorBtn{
    padding: 6px;
   }
  
   button{
    height: 85px;
    width: 55px;
   }
   .equalBtn, .resetBtn{
    width: 150px;
  }
  input{
    width: 330px;
  }
  .header{
    display: grid;
    grid-template-columns: 1rem 13rem 1rem;
    grid-gap: 30px;
   }
  }
@media (max-width:378px){
  .calculator{
    display: flex;
    justify-content: center;
    flex-direction: column;
    gap: 20px;
   }
   button{
    height: 95px;
    width: 50px;
   }
   .equalBtn, .resetBtn{
    width: 140px;
  }
  input{
    width: 300px;
  }
  .header{
    display: grid;
    grid-template-columns: 4rem 9rem 4rem;
    grid-gap: 30px;
   }
  }