:root {
  /* Theme 1 */
  --theme1-bg-main: hsl(222, 26%, 31%);
  --theme1-bg-toggle-keypad: hsl(223, 31%, 20%);
  --theme1-bg-screen: hsl(224, 36%, 15%);
  --theme1-key-bg: hsl(225, 21%, 49%);
  --theme1-key-shadow: hsl(224, 28%, 35%);
  --theme1-key-red: hsl(6, 63%, 50%);
  --theme1-key-red-shadow: hsl(6, 70%, 34%);
  --theme1-key-light-orange: hsl(30, 25%, 89%);
  --theme1-key-light-orange-shadow: hsl(28, 16%, 65%);
  --theme1-text-dark-blue: hsl(221, 14%, 31%);
  --theme1-text-white: hsl(0, 0%, 100%);

  /* Theme 2 */
  --theme2-bg-main: hsl(0, 0%, 90%);
  --theme2-bg-toggle-keypad: hsl(0, 5%, 81%);
  --theme2-bg-screen: hsl(0, 0%, 93%);
  --theme2-key-cyan: hsl(185, 42%, 37%);
  --theme2-key-cyan-shadow: hsl(185, 58%, 25%);
  --theme2-key-orange: hsl(25, 98%, 40%);
  --theme2-key-orange-shadow: hsl(25, 99%, 27%);
  --theme2-key-light-yellow: hsl(45, 7%, 89%);
  --theme2-key-light-yellow-shadow: hsl(35, 11%, 61%);
  --theme2-text-dark-yellow: hsl(60, 10%, 19%);
  --theme2-text-white: hsl(0, 0%, 100%);

  /* Theme 3 */
  --theme3-bg-main: hsl(268, 75%, 9%);
  --theme3-bg-toggle-keypad-screen: hsl(268, 72%, 14%);
  --theme3-key-violet: hsl(281, 89%, 26%);
  --theme3-key-magenta-shadow: hsl(285, 91%, 52%);
  --theme3-key-cyan: hsl(176, 100%, 44%);
  --theme3-key-cyan-shadow: hsl(177, 92%, 70%);
  --theme3-key-dark-violet: hsl(268, 47%, 21%);
  --theme3-key-dark-magenta-shadow: hsl(290, 70%, 36%);
  --theme3-text-light-yellow: hsl(52, 100%, 62%);
  --theme3-text-dark-blue: hsl(198, 20%, 13%);
  --theme3-text-white: hsl(0, 0%, 100%);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "League Spartan", sans-serif;
}

main {
  width: 100%;
  min-height: 100vh;
  height: fit-content;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 1em;
}

.header,
.display,
.keypad {
  width: 100%;
  max-width: 320px;
}

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 2.5rem;
  font-weight: 700;
}

.theme-switcher {
  display: flex;
  align-items: end;
  gap: 1em;
  text-transform: uppercase;
  font-weight: 700;
}

.theme-numbers {
  display: flex;
  align-items: center;
  padding: 0 10px;
  padding-bottom: 4px;
  justify-content: space-between;
}

.theme-btn {
  width: 14px;
  border: none;
  background: none;
  font-weight: 700;
  font-size: 1.2rem;
}

.theme-toggles {
  width: 74px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px;
  border-radius: 18px;
}

.toggle-btn {
  width: 14px;
  height: 14px;
  border-radius: 100%;
  background: none;
  border: none;
}

.display {
  width: 100%;
  height: 85px;
  border-radius: 10px;
  border: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  padding: 10px;
}

.display input {
  outline: none;
  border: none;
  text-align: right;
  font-weight: 700;
  background: none;
}

.calc-screen {
  width: 100%;
  font-size: 2.5rem;
}

.calc-screen-mini {
  width: 100%;
  font-size: 0.8rem;
}

.keypad {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.7em;
  padding: 24px 18px;
  border-radius: 10px;
}

.key {
  height: 60px;
  border: none;
  border-radius: 4px;
  margin: 0 0.1em;
  padding-bottom: 6px;
  overflow: hidden;
  font-size: 2rem;
}

.key div {
  width: 100%;
  height: 100%;
  border-radius: 4px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.key-reset,
.key-del {
  font-size: 1.4rem;
}

.key-reset,
.key-equal {
  grid-column: span 2;
}
button {
  cursor: pointer;
}
.theme1 {
  background: var(--theme1-bg-main);
  color: var(--theme1-key-light-orange);

  .logo {
    color: var(--theme1-key-light-orange);
  }
  .theme-toggles {
    background: var(--theme1-bg-screen);
  }
  .theme-btn {
    color: var(--theme1-key-light-orange);
  }

  .toggle-btn.theme1-btn {
    background: var(--theme1-key-red);
    border: none;
  }

  .display {
    background: var(--theme1-bg-screen);
  }

  .display input {
    color: var(--theme1-key-light-orange);
  }

  .key {
    background: var(--theme1-key-light-orange-shadow);
    color: var(--theme1-text-dark-blue);
  }

  .key div {
    background: var(--theme1-key-light-orange);
  }

  .keypad {
    background: var(--theme1-bg-toggle-keypad);
  }

  .key-del,
  .key-reset {
    background: var(--theme1-key-shadow);
  }

  .key-del div,
  .key-reset div {
    background: var(--theme1-key-bg);
    color: var(--theme1-key-light-orange);
  }

  .key-equal {
    background: var(--theme1-key-red-shadow);
  }

  .key-equal div {
    background: var(--theme1-key-red);
    color: var(--theme1-key-light-orange);
  }
}

.key:active {
  padding-bottom: 2px;
  transform: translateY(3px);
}

.theme2 {
  background: var(--theme2-bg-main);
  color: var(--theme2-text-dark-yellow);

  .theme-toggles {
    background: var(--theme2-bg-toggle-keypad);
  }
  .theme-btn {
    color: var(--theme2-text-dark-yellow);
  }

  .toggle-btn.theme2-btn {
    background: var(--theme2-key-orange);
    border: none;
  }

  .display {
    background: var(--theme2-bg-screen);
  }

  .display input {
    color: var(--theme2-text-dark-yellow);
  }

  .key {
    background: var(--theme2-key-light-yellow-shadow);
    color: var(--theme2-text-dark-yellow);
  }

  .key div {
    background: var(--theme2-key-light-yellow);
  }

  .keypad {
    background: var(--theme2-bg-toggle-keypad);
  }

  .key-del,
  .key-reset {
    background: var(--theme2-key-cyan-shadow);
  }

  .key-del div,
  .key-reset div {
    background: var(--theme2-key-cyan);
    color: var(--theme2-text-white);
  }

  .key-equal {
    background: var(--theme2-key-orange-shadow);
  }

  .key-equal div {
    background: var(--theme2-key-orange);
    color: var(--theme2-text-white);
  }
}

.theme3 {
  background: var(--theme3-bg-main);
  color: var(--theme3-text-light-yellow);

  .theme-toggles {
    background: var(--theme3-bg-toggle-keypad-screen);
  }
  .theme-btn {
    color: var(--theme3-text-light-yellow);
  }

  .toggle-btn.theme3-btn {
    background: var(--theme3-key-cyan);
    border: none;
  }

  .display {
    background: var(--theme3-bg-toggle-keypad-screen);
  }

  .display input {
    color: var(--theme3-text-light-yellow);
  }

  .key {
    background: var(--theme3-key-magenta-shadow);
    color: var(--theme3-text-light-yellow);
  }

  .key div {
    background: var(--theme3-key-violet);
  }

  .keypad {
    background: var(--theme3-bg-toggle-keypad-screen);
  }

  .key-del,
  .key-reset {
    background: var(--theme3-key-dark-magenta-shadow);
  }

  .key-del div,
  .key-reset div {
    background: var(--theme3-key-dark-violet);
    color: var(--theme3-text-white);
  }

  .key-equal {
    background: var(--theme3-key-cyan-shadow);
  }

  .key-equal div {
    background: var(--theme3-key-cyan);
    color: var(--theme3-text-dark-blue);
  }
}