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

:root {
  /*Theme 1*/
  --theme-1-main-bg: hsl(222, 26%, 31%);
  --theme-1-toggle-and-keypad-bg: hsl(223, 31%, 20%);
  --theme-1-screen-bg: hsl(224, 36%, 15%);
  --theme-1-screen-text: white;
  --theme-1-filled-key-bg: hsl(225, 21%, 49%);
  --theme-1-filled-key-shadow: hsl(224, 28%, 35%);
  --theme-1-filled-hv: hsl(224, 51%, 76%);
  --theme-1-equal-and-toggle-ball-bg: hsl(6, 63%, 50%);
  --theme-1-equal-and-toggle-ball-hv: hsl(6, 93%, 67%);
  --theme-1-equal-shadow: hsl(6, 70%, 34%);
  --theme-1-hollow-key-bg: hsl(30, 25%, 89%);
  --theme-1-hollow-key-shadow: hsl(28, 16%, 65%);
  --theme-1-hollow-hv: white;
  --theme-1-btn-text: hsl(221, 14%, 31%);
  --theme-1-equal-text: white;
  --theme-1-body-text: white;

  /*Theme 2*/
  --theme-2-main-bg: hsl(0, 0%, 90%);
  --theme-2-toggle-and-keypad-bg: hsl(0, 5%, 81%);
  --theme-2-screen-bg: hsl(0, 0%, 93%);
  --theme-2-screen-text: hsl(60, 10%, 19%);
  --theme-2-filled-key-bg: hsl(185, 42%, 37%);
  --theme-2-filled-key-shadow: hsl(185, 58%, 25%);
  --theme-2-filled-hv: hsl(186, 41%, 56%);
  --theme-2-equal-and-toggle-ball-bg: hsl(25, 98%, 40%);
  --theme-2-equal-and-toggle-ball-hv: hsl(25, 100%, 61%);
  --theme-2-equal-shadow: hsl(25, 99%, 27%);
  --theme-2-hollow-key-bg: hsl(45, 7%, 89%);
  --theme-2-hollow-key-shadow: hsl(35, 11%, 61%);
  --theme-2-hollow-hv: white;
  --theme-2-btn-text: hsl(60, 10%, 19%);
  --theme-2-equal-text: white;
  --theme-2-body-text: hsl(60, 10%, 19%);

  /*Theme 3*/
  --theme-3-main-bg: hsl(268, 75%, 9%);
  --theme-3-toggle-and-keypad-bg: hsl(268, 71%, 12%);
  --theme-3-screen-bg: hsl(268, 71%, 12%);
  --theme-3-screen-text: hsl(52, 100%, 62%);
  --theme-3-filled-key-bg: hsl(281, 89%, 26%);
  --theme-3-filled-key-shadow: hsl(285, 91%, 52%);
  --theme-3-filled-hv: hsl(280, 56%, 44%);
  --theme-3-equal-and-toggle-ball-bg: hsl(176, 100%, 44%);
  --theme-3-equal-and-toggle-ball-hv: hsl(176, 100%, 79%);
  --theme-3-equal-shadow: hsl(177, 92%, 70%);
  --theme-3-hollow-key-bg: hsl(268, 47%, 21%);
  --theme-3-hollow-key-shadow: hsl(290, 70%, 36%);
  --theme-3-hollow-hv: hsl(267, 53%, 44%);
  --theme-3-btn-text: hsl(52, 100%, 62%);
  --theme-3-equal-text: hsl(198, 20%, 13%);
  --theme-3-body-text: hsl(52, 100%, 62%);

  /*Default Theme Variables*/

  --main-bg: var(--theme-1-main-bg);
  --toggle-and-keypad-bg: var(--theme-1-toggle-and-keypad-bg);
  --screen-bg: var(--theme-1-screen-bg);
  --screen-text: var(--theme-1-screen-text);
  --filled-key-bg: var(--theme-1-filled-key-bg);
  --filled-key-shadow: var(--theme-1-filled-key-shadow);
  --filled-hv: var(--theme-1-filled-hv);
  --equal-and-toggle-ball-bg: var(--theme-1-equal-and-toggle-ball-bg);
  --equal-and-toggle-ball-hv: var(--theme-1-equal-and-toggle-ball-hv);
  --equal-shadow: var(--theme-1-equal-shadow);
  --hollow-key-bg: var(--theme-1-hollow-key-bg);
  --hollow-key-shadow: var(--theme-1-hollow-key-shadow);
  --hollow-hv: var(--theme-1-hollow-hv);
  --btn-text: var(--theme-1-btn-text);
  --equal-text: var(--theme-1-equal-text);
  --body-text: var(--theme-1-body-text);

  /*Screen Desktop*/
  --fs-screen-desktop: 54px;
  --fs-screen-mobile: 38px;
}

body {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 94px 0;
  color: var(--body-text);
  background: var(--main-bg);
  font-family: sans-serif;
  font-weight: 700;
  transition: all 0.5s linear;
}

.calculator {
  width: 540px;
}

.top-bar {
  display: flex;
  justify-content: space-between;
}

.cal-title {
  font-size: 31px;
  padding-left: 8px;
  top: 14px;
}

.themeContainer {
  display: flex;
  flex-direction: row;
  align-items: flex-end;
  gap: 28px;
  text-transform: uppercase;
}

.themeContainer small {
  font-size: 12px;
  letter-spacing: 1px;
  margin-right: -2px;
  margin-bottom: 5px;
}

.themeContainer form {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 71px;
}

.themeContainer form .themeNum {
  display: flex;
  gap: 15px;
  margin-bottom: 5px;
  font-size: 14px;
}

#themeThumb {
  width: 100%;
  display: flex;
  justify-content: space-between;
  gap: 0;
  height: 26px;
  padding: 5px;
  border-radius: 50px;
  background: var(--toggle-and-keypad-bg);
}

#themeThumb {
  background: var(--toggle-and-keypad-bg);
}

input[name="theme"]:checked {
  background: var(--equal-and-toggle-ball-bg);
}

input[type="radio"] {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  outline: none;
  border-radius: 50%;
  cursor: pointer;
}

button {
  height: 60px;
  font: inherit;
  font-size: 40px;
  border-radius: 10px;
  border: none;
  outline: none;
  cursor: pointer;
  transition: all 0.5s linear;
}

.valueBox {
  border-radius: 6px;
  padding: 32px 32px 36px;
  gap: 28px 25px;
}

.valueBox {
  background: var(--toggle-and-keypad-bg);
}

.colorDisplay {
  padding-top: 6px;
  background: var(--hollow-key-bg);
  color: var(--btn-text);
  box-shadow: 0 4px 0 var(--hollow-key-shadow);
}

.colorDisplay:hover {
  background: var(--hollow-hv);
}

.cal-value {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  text-align: center;
  border-radius: 6px;
  padding: 32px 32px 36px;
  gap: 28px 25px;
}

.cal-value {
  background: var(--toggle-and-keypad-bg);
}

.btn {
  height: 60px;
  font: inherit;
  font-size: 40px;
  border-radius: 10px;
  border: none;
  outline: none;
  cursor: pointer;
  transition: all 0.5s linear;
  color: var(--btn-text);
}

.operator {
  text-transform: uppercase;
  font-size: 28px;
  padding-top: 4px;
  background: var(--filled-key-bg);
  color: white;
  box-shadow: 0 4px 0 var(--filled-key-shadow);
}

.operator :hover {
  background: var(--filled-hv);
}

#delete {
  background-color: #a2b2e2;
  color: white;
}

.controller {
  display: flex;
  align-items: center;
  justify-content: space-between;
  display: grid;
  padding: 0 1em 1em 1em;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  cursor: pointer;
}

#reset {
  background: var(--filled-key-bg);
  box-shadow: 0 4px 0 var(--filled-key-shadow);
  padding: 8px 10px;
  text-align: center;
  border-radius: 7px;
  color: white;
  font-weight: bolder;
  font-size: 1.1em;
  cursor: pointer;
  grid-column: span 2;
}

.Equal-to {
  grid-column: span 2;
  font-size: 26px;
  padding-top: 4px;
  background: var(--equal-and-toggle-ball-bg);
  color: white;
  box-shadow: 0 4px 0 var(--equal-shadow);
  cursor: pointer;
  grid-column: span 2;
}

#input-box {
  background: var(--screen-bg);
  border-radius: 5px;
  outline: none;
  border: none;
  margin: 0.5em 0;
  font-size: var(--fs-screen-desktop);
  color: var(--screen-text);
  text-align: right;
  width: 100%;
  height: 100%;
  transition: all 0.5s linear;
  padding: 0.5em 0.7em;
  font-weight: 700;
}

.visuallyHidden {
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  height: 1px;
  overflow: hidden;
  position: absolute;
  white-space: nowrap;
  width: 1px;
}

/*Theme 2*/

[data-theme="light"] {
  --main-bg: var(--theme-2-main-bg);
  --toggle-and-keypad-bg: var(--theme-2-toggle-and-keypad-bg);
  --screen-bg: var(--theme-2-screen-bg);
  --screen-text: var(--theme-2-screen-text);
  --filled-key-bg: var(--theme-2-filled-key-bg);
  --filled-key-shadow: var(--theme-2-filled-key-shadow);
  --filled-hv: var(--theme-2-filled-hv);
  --equal-and-toggle-ball-bg: var(--theme-2-equal-and-toggle-ball-bg);
  --equal-and-toggle-ball-hv: var(--theme-2-equal-and-toggle-ball-hv);
  --equal-shadow: var(--theme-2-equal-shadow);
  --hollow-key-bg: var(--theme-2-hollow-key-bg);
  --hollow-key-shadow: var(--theme-2-hollow-key-shadow);
  --hollow-hv: var(--theme-2-hollow-hv);
  --btn-text: var(--theme-2-btn-text);
  --equal-text: var(--theme-2-equal-text);
  --body-text: var(--theme-2-body-text);
}

/*Theme 3*/

[data-theme="purple"] {
  --main-bg: var(--theme-3-main-bg);
  --toggle-and-keypad-bg: var(--theme-3-toggle-and-keypad-bg);
  --screen-bg: var(--theme-3-screen-bg);
  --screen-text: var(--theme-3-screen-text);
  --filled-key-bg: var(--theme-3-filled-key-bg);
  --filled-key-shadow: var(--theme-3-filled-key-shadow);
  --filled-hv: var(--theme-3-filled-hv);
  --equal-and-toggle-ball-bg: var(--theme-3-equal-and-toggle-ball-bg);
  --equal-and-toggle-ball-hv: var(--theme-3-equal-and-toggle-ball-hv);
  --equal-shadow: var(--theme-3-equal-shadow);
  --hollow-key-bg: var(--theme-3-hollow-key-bg);
  --hollow-key-shadow: var(--theme-3-hollow-key-shadow);
  --hollow-hv: var(--theme-3-hollow-hv);
  --btn-text: var(--theme-3-btn-text);
  --equal-text: var(--theme-3-equal-text);
  --body-text: var(--theme-3-body-text);
}