:root {
  color-scheme: light dark;
  --page-bg: #edf4f2;
  --page-accent: rgba(44, 121, 126, 0.12);
  --text: #16252d;
  --muted: #607480;
  --accent: #1a7c83;
  --accent-strong: #0d5b61;
  --accent-soft: rgba(26, 124, 131, 0.16);
  --success: #2d7f54;
  --error: #b75342;
  --error-soft: rgba(183, 83, 66, 0.16);
  --error-line: rgba(183, 83, 66, 0.74);
  --calc-shell-top: #2b3d49;
  --calc-shell-bottom: #18232b;
  --calc-shell-line: rgba(255, 255, 255, 0.06);
  --screen-top: #eff8f4;
  --screen-bottom: #d7e7df;
  --screen-text: #102027;
  --screen-muted: #617783;
  --screen-line: rgba(9, 39, 43, 0.12);
  --screen-shadow: 0 18px 34px rgba(10, 28, 32, 0.16);
  --key-top: #ffffff;
  --key-bottom: #dfe7ec;
  --key-text: #15232b;
  --key-shadow: 0 10px 18px rgba(0, 0, 0, 0.18);
  --key-accent-top: #a2d8d7;
  --key-accent-bottom: #6db8b8;
  --key-accent-text: #10363a;
  --control-top: #394d5b;
  --control-bottom: #273842;
  --control-text: #edf5f5;
  --footer-text: #20323c;
  --footer-bg: rgba(255, 255, 255, 0.7);
  --footer-line: rgba(22, 37, 45, 0.14);
  --keypad-label: #a0b8c0;
  --status-default: #cad8dd;
  --status-error: #ffc1b6;
  --status-success: #bfe9cc;
  --status-hint: #b9ccd2;
  --radius-xl: 32px;
  --radius-lg: 24px;
  --radius-md: 18px;
  --radius-sm: 14px;
  --key-row-min: 3.55rem;
  --app-height: 100svh;
  --font-ui: "Avenir Next", "SF Pro Display", "SF Pro Text", "Helvetica Neue",
    sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --page-bg: #10181d;
    --page-accent: rgba(93, 177, 184, 0.12);
    --text: #edf5f5;
    --muted: #a3bac0;
    --accent: #74c3c6;
    --accent-strong: #99d9db;
    --accent-soft: rgba(116, 195, 198, 0.16);
    --success: #89d7ac;
    --error: #ff9381;
    --error-soft: rgba(255, 147, 129, 0.18);
    --error-line: rgba(255, 147, 129, 0.76);
    --calc-shell-top: #24333d;
    --calc-shell-bottom: #121a20;
    --calc-shell-line: rgba(255, 255, 255, 0.05);
    --screen-top: #253239;
    --screen-bottom: #1c2930;
    --screen-text: #edf5f5;
    --screen-muted: #b1c3c8;
    --screen-line: rgba(237, 245, 245, 0.08);
    --screen-shadow: 0 18px 36px rgba(0, 0, 0, 0.28);
    --key-top: #f5f7fa;
    --key-bottom: #d7e0e5;
    --key-text: #132028;
    --key-shadow: 0 10px 18px rgba(0, 0, 0, 0.22);
    --key-accent-top: #8fcbca;
    --key-accent-bottom: #66b0b0;
    --key-accent-text: #0d3134;
    --control-top: #314550;
    --control-bottom: #22313b;
    --control-text: #edf5f5;
    --footer-text: #e4f0f2;
    --footer-bg: rgba(18, 26, 32, 0.58);
    --footer-line: rgba(255, 255, 255, 0.08);
  }
}

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
  touch-action: manipulation;
}

body {
  min-height: 100svh;
  min-height: var(--app-height);
  margin: 0;
  overscroll-behavior: none;
  font-family: var(--font-ui);
  color: var(--text);
  background:
    radial-gradient(circle at top left, var(--page-accent), transparent 40%),
    radial-gradient(circle at bottom right, rgba(238, 141, 84, 0.08), transparent 28%),
    var(--page-bg);
}

body,
button {
  -webkit-tap-highlight-color: transparent;
}

button {
  font: inherit;
  cursor: pointer;
  user-select: none;
  touch-action: manipulation;
}

.app-shell {
  width: min(100%, 29rem);
  height: var(--app-height);
  min-height: 100svh;
  min-height: var(--app-height);
  margin: 0 auto;
  display: grid;
  grid-template-rows: minmax(0, 1fr) auto;
  gap: 0.15rem;
  padding:
    max(0.75rem, env(safe-area-inset-top))
    0.85rem
    max(0.1rem, env(safe-area-inset-bottom));
}

.panel.calculator-body {
  min-height: 0;
  display: flex;
  padding: 0.8rem;
  border: 1px solid var(--calc-shell-line);
  border-radius: var(--radius-xl);
  background: linear-gradient(180deg, var(--calc-shell-top), var(--calc-shell-bottom));
  box-shadow: 0 28px 64px rgba(11, 20, 25, 0.28);
}

.app-footer {
  margin: 0.1rem 0 0;
  justify-self: center;
  padding: 0.38rem 0.8rem;
  color: var(--footer-text);
  background: var(--footer-bg);
  border: 1px solid var(--footer-line);
  border-radius: 999px;
  box-shadow:
    0 10px 24px rgba(11, 20, 25, 0.1),
    inset 0 1px 0 rgba(255, 255, 255, 0.38);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.03em;
  line-height: 1.3;
  text-align: center;
}

.calculator {
  flex: 1;
  min-height: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  gap: 0.7rem;
}

.screen-panel,
.keypad-card {
  border-radius: var(--radius-lg);
}

.screen-panel {
  display: grid;
  gap: 0.7rem;
  padding: 0.8rem;
  color: var(--screen-text);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.22), rgba(255, 255, 255, 0) 28%),
    linear-gradient(180deg, var(--screen-top), var(--screen-bottom));
  border: 1px solid var(--screen-line);
  box-shadow: var(--screen-shadow);
}

.display-tile,
.result-card,
.keypad-button,
.operator-key,
.utility-key,
.mode-key,
.equals-key {
  width: 100%;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  touch-action: manipulation;
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    background-color 160ms ease,
    color 160ms ease,
    box-shadow 160ms ease;
}

.display-tile,
.result-card {
  background: rgba(255, 255, 255, 0.3);
  border-color: var(--screen-line);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.45);
}

.display-tile {
  display: grid;
  gap: 0.35rem;
  padding: 0.8rem 0.9rem;
  color: var(--screen-text);
  text-align: right;
}

.display-tile-primary {
  min-height: 5.4rem;
}

.display-tile-secondary {
  min-height: 4.8rem;
}

.tile-topline,
.result-topline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.tile-label,
.result-topline h1 {
  margin: 0;
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.tile-label {
  color: var(--screen-muted);
}

.tile-symbol {
  font-size: 1.05rem;
  color: var(--accent-strong);
}

.tile-state,
.tile-hint,
.equation-preview,
.status-message {
  margin: 0;
}

.tile-state,
.tile-hint,
.equation-preview {
  color: var(--screen-muted);
}

.tile-state,
.tile-hint {
  font-size: 0.8rem;
  line-height: 1.35;
}

.tile-value,
.result-value {
  font-variant-numeric: tabular-nums;
}

.tile-value {
  font-size: clamp(3.45rem, 16vw, 5.25rem);
  font-weight: 900;
  line-height: 0.92;
  letter-spacing: -0.08em;
}

.amount-value {
  font-size: clamp(2.85rem, 13.2vw, 4.2rem);
}

.operation-pill,
.day-chip {
  padding: 0.32rem 0.62rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 800;
}

.operation-pill {
  color: var(--screen-text);
  background: rgba(255, 255, 255, 0.42);
  border: 1px solid var(--screen-line);
}

.result-card {
  position: relative;
  overflow: hidden;
  display: grid;
  gap: 0.45rem;
  padding: 0.85rem 0.9rem;
  cursor: pointer;
  transition:
    transform 140ms ease,
    box-shadow 140ms ease,
    background-color 140ms ease,
    border-color 140ms ease;
  -webkit-tap-highlight-color: transparent;
}

.result-topline h1 {
  color: var(--screen-muted);
}

.day-chip {
  color: var(--accent-strong);
  background: rgba(26, 124, 131, 0.12);
}

.result-value {
  margin: 0;
  font-size: clamp(3.9rem, 18vw, 5.9rem);
  font-weight: 900;
  line-height: 0.9;
  letter-spacing: -0.1em;
}

.equation-preview {
  min-height: calc(1.08rem * 1.35);
  color: var(--screen-text);
  font-size: 1.08rem;
  font-weight: 800;
  line-height: 1.35;
  letter-spacing: -0.02em;
  text-align: right;
  text-wrap: balance;
}

.result-copy-hint {
  margin: 0;
  color: var(--screen-muted);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  transition:
    color 180ms ease,
    transform 180ms ease,
    letter-spacing 180ms ease;
}

.result-card[data-copy-ready="true"] {
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.5),
    0 0 0 1px rgba(26, 124, 131, 0.14);
}

.result-card[data-copy-ready="true"]::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  opacity: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at center, rgba(255, 255, 255, 0.42), transparent 54%);
  transition: opacity 140ms ease;
}

.result-card[data-copy-pressing="true"] {
  transform: translateY(3px) scale(0.978);
  border-color: rgba(26, 124, 131, 0.34);
  box-shadow:
    inset 0 0.2rem 0.55rem rgba(10, 39, 43, 0.12),
    inset 0 1px 0 rgba(255, 255, 255, 0.42),
    0 0 0 2px rgba(26, 124, 131, 0.12);
}

.result-card[data-copy-pressing="true"]::after {
  opacity: 1;
}

.result-card[data-copy-pressing="true"] .result-value {
  transform: scale(0.985);
}

.result-card[data-copy-feedback="true"] {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.03)),
    linear-gradient(180deg, #eef8f0, #dbe8df);
  border-color: rgba(45, 127, 84, 0.26);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.62),
    0 0 0 3px rgba(45, 127, 84, 0.12),
    0 0.7rem 1.35rem rgba(18, 65, 43, 0.12);
  transform: scale(1.008);
  animation: copy-result-flash 680ms cubic-bezier(0.2, 0.9, 0.2, 1);
}

.result-card[data-copy-feedback="true"] .result-value,
.result-card[data-copy-feedback="true"] .equation-preview {
  color: #143927;
}

.result-card[data-copy-feedback="true"] .result-copy-hint,
.result-card[data-copy-feedback="true"] .day-chip {
  color: #215f3f;
}

.result-card[data-copy-feedback="true"] .result-copy-hint {
  transform: translateY(-0.08rem) scale(1.02);
  letter-spacing: 0.08em;
}

.result-card[data-copy-ready="true"]:active {
  transform: translateY(3px) scale(0.978);
}

.result-card:focus-visible {
  outline: none;
  box-shadow: 0 0 0 4px var(--accent-soft);
}

.result-card[aria-disabled="true"] {
  cursor: default;
}

.display-tile[aria-pressed="true"] {
  border-color: rgba(26, 124, 131, 0.5);
  background: rgba(255, 255, 255, 0.44);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.5),
    0 0 0 3px var(--accent-soft);
}

.display-tile.is-invalid {
  border-color: var(--error-line);
  box-shadow: 0 0 0 4px var(--error-soft);
}

.keypad-card {
  min-height: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  align-content: stretch;
  gap: 0.7rem;
  padding: 0.8rem;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0)),
    var(--calc-shell-bottom);
}

.utility-row {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  grid-auto-rows: minmax(var(--key-row-min), auto);
  gap: 0.55rem;
}

.keypad-grid-calculator {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  grid-auto-rows: minmax(var(--key-row-min), 1fr);
  min-height: 0;
  height: 100%;
  align-content: stretch;
  gap: 0.55rem;
}

.keypad-button,
.operator-key,
.utility-key,
.mode-key,
.equals-key {
  min-height: 0;
  height: 100%;
  padding: 0.65rem 0.4rem;
  border-color: rgba(11, 21, 27, 0.14);
  position: relative;
  overflow: hidden;
  transform: translateY(0) scale(1);
  box-shadow:
    0 0.32rem 0 rgba(10, 19, 24, 0.22),
    var(--key-shadow),
    inset 0 1px 0 rgba(255, 255, 255, 0.84);
  transition:
    transform 70ms cubic-bezier(0.2, 0.9, 0.3, 1),
    border-color 120ms ease,
    background-color 120ms ease,
    color 120ms ease,
    box-shadow 70ms cubic-bezier(0.2, 0.9, 0.3, 1),
    filter 80ms ease;
}

.keypad-card button {
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  touch-action: none;
}

.keypad-button,
.mode-key {
  color: var(--key-text);
  background: linear-gradient(180deg, var(--key-top), var(--key-bottom));
}

.keypad-button {
  font-size: 2rem;
  font-weight: 900;
  line-height: 1;
}

.keypad-button::after,
.operator-key::after,
.utility-key::after,
.mode-key::after,
.equals-key::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  opacity: 0;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.18), rgba(255, 255, 255, 0)),
    radial-gradient(circle at 50% 38%, rgba(255, 255, 255, 0.28), transparent 56%);
  transition: opacity 70ms ease;
}

.keypad-button-muted,
.equals-key {
  color: var(--key-accent-text);
  background: linear-gradient(180deg, var(--key-accent-top), var(--key-accent-bottom));
}

.operator-key,
.utility-key {
  color: var(--control-text);
  background: linear-gradient(180deg, var(--control-top), var(--control-bottom));
}

.operator-key {
  font-size: 2.28rem;
  font-weight: 900;
  line-height: 1;
}

.operator-key[aria-pressed="true"] {
  color: var(--key-accent-text);
  background: linear-gradient(180deg, var(--key-accent-top), var(--key-accent-bottom));
}

.utility-key,
.mode-key {
  font-size: 1.1rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.05;
}

.utility-key-round {
  padding-inline: 0.25rem;
  font-size: 1.26rem;
  font-weight: 900;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.04em;
  white-space: nowrap;
}

.utility-key[data-key="backspace"] {
  font-size: 1.3rem;
  font-weight: 900;
  line-height: 1;
  letter-spacing: -0.03em;
}

.equals-key {
  grid-row: span 2;
  font-size: 2.5rem;
  font-weight: 900;
  line-height: 1;
}

.utility-key:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

.utility-key-danger {
  background: linear-gradient(180deg, #7f544d, #623d37);
}

.status-message {
  min-height: 1.35rem;
  color: var(--status-default);
  font-size: 0.92rem;
  line-height: 1.4;
}

.status-message[data-state="error"] {
  color: var(--status-error);
  font-weight: 800;
}

.status-message[data-state="success"] {
  color: var(--status-success);
  font-weight: 800;
}

.status-message[data-state="hint"] {
  color: var(--status-hint);
}

button:active {
  transform: translateY(2px) scale(0.97);
}

.keypad-card button:active {
  transform: translateY(0.34rem) scale(0.955);
  box-shadow:
    0 0.08rem 0 rgba(10, 19, 24, 0.22),
    0 0.28rem 0.68rem rgba(0, 0, 0, 0.18),
    inset 0 0.18rem 0.34rem rgba(9, 20, 26, 0.22),
    inset 0 1px 0 rgba(255, 255, 255, 0.34);
}

.keypad-card button[data-pressing="true"] {
  transform: translateY(0.38rem) scale(0.948);
  border-color: rgba(6, 20, 26, 0.24);
  box-shadow:
    0 0.06rem 0 rgba(10, 19, 24, 0.24),
    0 0.2rem 0.56rem rgba(0, 0, 0, 0.16),
    inset 0 0.22rem 0.44rem rgba(8, 19, 25, 0.24),
    inset 0 1px 0 rgba(255, 255, 255, 0.28);
  filter: saturate(0.94) brightness(0.97);
}

.keypad-card button[data-pressing="true"]::after {
  opacity: 1;
}

button:focus-visible {
  outline: none;
  box-shadow: 0 0 0 4px var(--accent-soft);
}

@keyframes copy-result-flash {
  0% {
    transform: translateY(3px) scale(0.978);
  }

  38% {
    transform: translateY(-0.08rem) scale(1.012);
  }

  100% {
    transform: scale(1.008);
  }
}

/* La calculadora limita su ancho a 29rem incluso en escritorio. Si la ventana
   es ancha pero baja, el viewport no cumple max-width: 480px y el tamaño
   grande podía desbordar verticalmente. El mismo modo compacto se activa por
   altura para mantener siempre accesibles el teclado y el footer. */
@media (max-width: 480px), (max-height: 920px) {
  :root {
    --key-row-min: 2.82rem;
  }

  .app-shell {
    padding:
      max(0.35rem, env(safe-area-inset-top))
      0.48rem
      max(0.48rem, env(safe-area-inset-bottom));
  }

  .panel.calculator-body {
    padding: 0.48rem;
    border-radius: 24px;
  }

  .app-footer {
    margin-top: 0.42rem;
    padding: 0.3rem 0.68rem;
    font-size: 0.62rem;
  }

  .calculator {
    gap: 0.48rem;
  }

  .screen-panel,
  .keypad-card {
    gap: 0.48rem;
    padding: 0.58rem;
    border-radius: 18px;
  }

  .display-tile {
    padding: 0.58rem 0.65rem;
  }

  .display-tile-primary {
    min-height: 4.3rem;
  }

  .display-tile-secondary {
    min-height: 4rem;
  }

  .tile-label,
  .result-topline h1,
  .keypad-head h2 {
    font-size: 0.63rem;
  }

  .tile-symbol {
    font-size: 0.85rem;
  }

  .tile-state,
  .tile-hint,
  .equation-preview,
  .result-copy-hint,
  .status-message,
  .operation-pill,
  .day-chip {
    font-size: 0.66rem;
  }

  .tile-value {
    font-size: clamp(2.65rem, 12.8vw, 3.5rem);
  }

  .amount-value {
    font-size: clamp(2.18rem, 10.7vw, 2.95rem);
  }

  .result-card {
    gap: 0.3rem;
    padding: 0.58rem 0.65rem;
  }

  .result-value {
    font-size: clamp(2.95rem, 14vw, 4rem);
  }

  .equation-preview {
    min-height: calc(0.84rem * 1.35);
    font-size: 0.84rem;
  }

  .keypad-button,
  .operator-key,
  .utility-key,
  .mode-key,
  .equals-key {
    padding: 0.35rem 0.25rem;
    border-radius: 12px;
  }

  .keypad-button {
    font-size: 1.42rem;
  }

  .operator-key {
    font-size: 1.7rem;
  }

  .utility-key,
  .mode-key {
    font-size: 0.84rem;
  }

  .utility-key-round {
    font-size: 1rem;
  }

  .utility-key[data-key="backspace"] {
    font-size: 1.08rem;
  }

  .equals-key {
    font-size: 1.82rem;
  }

  .utility-row,
  .keypad-grid-calculator {
    gap: 0.4rem;
  }
}

@media (max-width: 380px) and (max-height: 700px) {
  :root {
    --key-row-min: 2.4rem;
  }

  .result-copy-hint {
    display: none;
  }
}

@media (min-height: 860px) and (max-width: 500px) {
  .app-shell {
    gap: 0.45rem;
  }

  .panel.calculator-body {
    padding: 0.62rem;
  }

  .calculator,
  .screen-panel,
  .keypad-card {
    gap: 0.62rem;
  }

  .screen-panel,
  .keypad-card {
    padding: 0.72rem;
  }

  .tile-value {
    font-size: clamp(3rem, 11.4vw, 4.2rem);
  }

  .amount-value {
    font-size: clamp(2.45rem, 10vw, 3.4rem);
  }

  .result-value {
    font-size: clamp(3.45rem, 13.2vw, 4.8rem);
  }
}