/* -----------------------------------------------------
   Calculator Modal Styling
   ----------------------------------------------------- */

/* CSS variable definitions */
:root {
  --calculator-width: 20rem;
  --display-height: 5rem;
  --key-height: 3.5rem;
  --gap-keys: 0.6rem;
  --gap-display-to-keys: 1.8rem;
}

/* -----------------------------------------------------
   Overlay and Modal Container
   ----------------------------------------------------- */
#calculatorOverlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: transparent;
  z-index: 9999;
  display: none;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.3s ease;
}

/* Active overlay state */
#calculatorOverlay.active {
  opacity: 1;
  pointer-events: auto;
  background-color: rgba(0, 0, 0, 0.5);
}

/* Calculator modal window (container) */
#calculatorModal {
  position: absolute;
  z-index: 10000;
  padding: 4rem 1rem 1rem 1rem;
  border-radius: 16px;
  background-color: var(--modal-bg);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.5);
  border: 1px solid var(--modal-border);
  backdrop-filter: blur(12px);
  pointer-events: auto;
  width: fit-content;
  max-width: 90vw;
  white-space: normal;
  cursor: grab;
}

/* -----------------------------------------------------
   Close button
   ----------------------------------------------------- */
#calculatorModal .close-btn {
  all: unset;
  position: absolute;
  top: 12px;
  right: 6px;
  width: 28px;
  height: 28px;
  background: var(--close-btn-bg);
  color: white;
  border-radius: 50%;
  font-size: 16px;
  text-align: center;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

#calculatorModal .close-btn:hover {
  background: var(--close-btn-hover-bg);
}

/* Calculator body (actual calculator area including buttons and display) */
#calculatorOverlay .calculator {
  width: var(--calculator-width);
  display: flex;
  flex-direction: column;
  gap: var(--gap-display-to-keys);
  background: linear-gradient(145deg, #b8bfb8, #9aa09a);
  transition: opacity 0.01;
  border-radius: 12px;
  padding: 1rem;
 /* backdrop-filter: blur(12px);*/
  border-top: 1px solid rgba(255, 255, 255, 0.6);
  border-left: 1px solid rgba(255, 255, 255, 0.6);
  border-right: 1px solid rgba(0, 0, 0, 0.3);
  border-bottom: 1px solid rgba(0, 0, 0, 0.3);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

/* Calculator display */
#calculatorOverlay .display {
  transition: opacity 0.3s ease;
  height: var(--display-height);
  background: linear-gradient(180deg, #1a2a1a, #0d1a0d);
  color: #90ee90;
  font-family: 'DS-Digital', sans-serif;
  font-size: 3rem;
  padding: 0.25rem 0.5rem;
  border-radius: 8px;
  border: 2px inset rgba(0, 0, 0, 0.5);
  text-align: right;
  box-shadow: inset 0 2px 8px rgba(0, 0, 0, 0.5);
  direction: ltr;
  white-space: nowrap;
  overflow-x: auto; /* Allow horizontal scrolling to see hidden content */
  overflow-y: hidden; /* Keep vertical overflow hidden */
  text-overflow: clip;
  scrollbar-width: none; /* Hide scrollbar for Firefox */
  -ms-overflow-style: none; /* Hide scrollbar for IE 10+ */
  user-select: text; /* Allow text selection */
  -webkit-user-select: text; /* Safari support */
  -moz-user-select: text; /* Firefox support */
  -ms-user-select: text; /* IE/Edge support */
  cursor: text; /* Change mouse cursor to text selection */
  pointer-events: auto; /* Allow events on the display itself */
}
#calculatorOverlay .display::-webkit-scrollbar {
  display: none; /* Hide scrollbar for Chrome, Safari */
}

/* Button grid container */
#calculatorOverlay .keys {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-auto-rows: var(--key-height);
  gap: var(--gap-keys);
}

/* Base style for all buttons */
#calculatorOverlay button {
  border-radius: 6px;
  font-size: 1.4rem;
  color: #333; 
  padding: 0.375rem 0;
  font-weight: 600;
  cursor: pointer;
  border-top: 2px solid rgba(255, 255, 255, 0.8);
  border-left: 2px solid rgba(255, 255, 255, 0.8);
  border-right: 2px solid rgba(0, 0, 0, 0.3);
  border-bottom: 2px solid rgba(0, 0, 0, 0.3);
  background: linear-gradient(145deg, #e8e8e8, #d0d0d0);
  box-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
  transition: all 0.1s ease-in-out;
}

/* Specific button group color overrides */
#calculatorOverlay .control.ac {
  background: linear-gradient(145deg, #e05050, #c03030);
  color: #fff;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

#calculatorOverlay .control.enter {
  background: linear-gradient(145deg, #50a060, #308040);
  color: #fff;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

#calculatorOverlay .control {
  background: linear-gradient(145deg, #d05050, #b03030);
  color: #fff;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

#calculatorOverlay .operator-button,
#calculatorOverlay .number {
  font-size: 1.8rem;
}

#calculatorOverlay .operator-button {
  background: linear-gradient(145deg, #c8c8c8, #a8a8a8);
  color: #333;
}

#calculatorOverlay .number {
  background: linear-gradient(145deg, #f5f5f5, #e0e0e0);
  color: #333;
}

/* Visual feedback when button is pressed */
#calculatorOverlay button:active,
#calculatorOverlay button.pressed {
  transform: translate(1px, 1px);
  border-top: 2px solid rgba(0, 0, 0, 0.3);
  border-left: 2px solid rgba(0, 0, 0, 0.3);
  border-right: 2px solid rgba(255, 255, 255, 0.8);
  border-bottom: 2px solid rgba(255, 255, 255, 0.8);
  box-shadow: inset 2px 2px 4px rgba(0, 0, 0, 0.25);
}

/* Control buttons (AC, DEL, ENTER) pressed state */
#calculatorOverlay .control.ac:active,
#calculatorOverlay .control.ac.pressed {
  background: linear-gradient(145deg, #c03030, #a02020);
}

#calculatorOverlay .control:active,
#calculatorOverlay .control.pressed {
  background: linear-gradient(145deg, #b03030, #901818);
}

#calculatorOverlay .control.enter:active,
#calculatorOverlay .control.enter.pressed {
  background: linear-gradient(145deg, #308040, #206030);
}

/* Number buttons pressed state */
#calculatorOverlay .number:active,
#calculatorOverlay .number.pressed {
  background: linear-gradient(145deg, #d8d8d8, #c0c0c0);
}

/* Operator buttons pressed state */
#calculatorOverlay .operator-button:active,
#calculatorOverlay .operator-button.pressed {
  background: linear-gradient(145deg, #a8a8a8, #888888);
}

/* Layout related */
#calculatorOverlay .span-2 {
  grid-column: span 2;
}

.teacher-login-modal {
    width: 320px !important;
    min-width: 0 !important;
    max-width: 90vw;
    padding: 24px 20px 20px 20px !important;
    box-sizing: border-box;
}