/* Interactive browser preview. The original calculator and native app are unchanged. */
.calculator { padding-top: 24px; padding-bottom: 14px; }
.calculator-heading { margin-bottom: 14px; }
.preview-label { color: #66745e; font-size: 11px; }
.mixed-expression { display: flex; justify-content: center; align-items: center; gap: 17px; padding: 8px 0 0; }
.mixed-number { width: 137px; }
.mixed-fields { display: grid; grid-template-columns: 62px 62px; gap: 13px; align-items: center; }
.mixed-fields input { background: #f5f6f2; border: 0; color: inherit; text-align: center; border-radius: 9px; width: 62px; height: 44px; padding: 3px; font-size: 28px; font-weight: 450; }
.mixed-fields input::placeholder { color: #6b7664; opacity: .7; }
.mixed-fields input.long { font-size: 17px; }
.mixed-fields input:focus-visible { outline-width: 2px; outline-offset: 2px; }
.mixed-fields .whole-field { height: 60px; font-size: 37px; }
.mixed-fields .selected { background: #f0f4eb; box-shadow: inset 0 0 0 1.5px #a6bb91; }
.fraction-fields { display: flex; flex-direction: column; gap: 4px; align-items: center; }
.fraction-fields .fraction-line { width: 42px; }
.field-labels { display: grid; grid-template-columns: 62px 62px; gap: 13px; text-align: center; font-size: 10px; color: #65735d; padding-top: 8px; }
.mixed-operation { display: grid; place-items: center; flex: 0 0 20px; color: #75826c; margin-top: -20px; }
.operation-symbol { width: 24px; height: 24px; stroke-width: 1.8; overflow: visible; }
.symbol-strokes { transform-origin: 12px 12px; transition: transform 240ms cubic-bezier(.16,1,.3,1); }
.symbol-vertical { transform-origin: 12px 12px; transition: opacity 140ms ease-out, transform 240ms cubic-bezier(.16,1,.3,1); }
.symbol-dot { fill: currentColor; stroke: none; opacity: 0; transition: opacity 180ms ease-out; }
.operation-symbol[data-operation="multiply"] .symbol-strokes { transform: rotate(45deg); }
.operation-symbol[data-operation="subtract"] .symbol-vertical,
.operation-symbol[data-operation="divide"] .symbol-vertical { opacity: 0; transform: scaleY(.1); }
.operation-symbol[data-operation="divide"] .symbol-dot { opacity: 1; }
.input-hint { text-align: center; font-size: 11px; color: #66715e; margin: 13px 0 15px; }
.operators { position: relative; isolation: isolate; margin-bottom: 16px; }
.operators::before { content: ""; position: absolute; z-index: -1; top: 5px; bottom: 5px; left: 5px; width: calc((100% - 31px) / 4); border-radius: 9px; background: var(--green); transform: translateX(var(--indicator-offset, 0px)); transition: transform 240ms cubic-bezier(.16,1,.3,1); }
.operators button { height: 42px; position: relative; transition: color 160ms ease-out, background 160ms ease-out; }
.operators button[aria-pressed="true"] { background: transparent; }
.operators button[aria-pressed="true"]:hover { background: transparent; }
.answer-panel { min-height: 0; padding: 8px 13px 10px; }
.answer { min-height: 56px; }
.answer-detail { min-height: 21px; }
.answer-heading .icon-button { width: 32px; height: 28px; }
.formats { margin-top: 4px; }
.formats button { min-height: 36px; font-size: 11px; }
.simple-keypad { display: grid; grid-template-columns: repeat(3, 1fr); grid-template-rows: repeat(4, 48px); gap: 7px; margin-top: 16px; }
.simple-keypad button { display: flex; justify-content: center; align-items: center; background: #f5f6f2; border-radius: 10px; font-size: 24px; font-weight: 450; }
.simple-keypad button:hover { background: #e9eee2; }
.simple-keypad .zero-key { grid-column: span 2; }
.simple-keypad .delete-key { color: #65745b; }
.simple-keypad svg { width: 21px; height: 21px; }
.calculate-button { width: 100%; min-height: 48px; margin-top: 9px; background: var(--green); color: #fff; border-radius: 10px; font-size: 15px; display: flex; align-items: center; justify-content: center; gap: 12px; }
.calculate-button span { font-size: 23px; line-height: 1; }
.calculate-button:hover { background: #37634e; }
.preview-caption { font-size: 10px; text-align: center; color: #6b7664; margin: 12px 0 0; }
.side-note .design-note { font-size: 10px; border-top: 1px solid var(--border); padding-top: 18px; margin-top: 24px; }
@media (max-width: 720px) {
  .site-header { height: 64px; }
  .calculator { padding: 8px 24px 10px; }
  .calculator-heading { margin-bottom: 6px; }
  .input-hint { margin: 9px 0 11px; }
  .operators { margin-bottom: 12px; }
  .simple-keypad { margin-top: 12px; }
  .preview-caption { margin-top: 8px; }
  .mixed-expression { gap: 12px; }
  .mixed-number { width: 130px; }
  .mixed-fields, .field-labels { grid-template-columns: 60px 60px; gap: 10px; }
  .mixed-fields input { width: 60px; }
  .answer { min-height: 56px; font-size: 42px; }
  .answer-detail { font-size: 10px; }
}
@media (max-width: 360px) {
  .calculator { padding-left: 18px; padding-right: 18px; }
  .mixed-expression { gap: 9px; }
  .mixed-number { width: 119px; }
  .mixed-fields, .field-labels { grid-template-columns: 56px 56px; gap: 7px; }
  .mixed-fields input { width: 56px; }
  .simple-keypad { grid-template-rows: repeat(4, 48px); }
}
@media (prefers-reduced-motion: reduce) {
  .operators::before, .symbol-strokes, .symbol-vertical, .symbol-dot { transition: none; }
}