/* Perc - Material Design 3 Percentage Calculator Stylesheet */

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700&family=Roboto+Mono:wght@400;500;600&display=swap');

:root {
  /* M3 Palette Tokens - Dark Theme Default */
  --md-sys-color-background: #0f1318;
  --md-sys-color-on-background: #e1e2e8;
  --md-sys-color-surface: #13171f;
  --md-sys-color-surface-dim: #0c0f14;
  --md-sys-color-surface-container: #1b2029;
  --md-sys-color-surface-container-high: #252b36;
  --md-sys-color-surface-container-highest: #303745;
  --md-sys-color-on-surface: #e1e2e8;
  --md-sys-color-on-surface-variant: #c1c6d4;
  --md-sys-color-outline: #414754;
  --md-sys-color-outline-variant: #2b313d;

  /* Accent Colors */
  --md-sys-color-primary: #78a0ff;
  --md-sys-color-on-primary: #002b74;
  --md-sys-color-primary-container: #194498;
  --md-sys-color-on-primary-container: #d9e2ff;

  --md-sys-color-secondary: #00d6b5;
  --md-sys-color-on-secondary: #00382e;
  --md-sys-color-secondary-container: #005143;
  --md-sys-color-on-secondary-container: #70f7d9;

  --md-sys-color-tertiary: #ff91a4;
  --md-sys-color-on-tertiary: #650024;
  --md-sys-color-tertiary-container: #8b1339;
  --md-sys-color-on-tertiary-container: #ffd9df;

  --md-sys-color-error: #ffb4ab;
  --md-sys-color-on-error: #690005;

  /* Shape & Elevation Tokens */
  --md-corner-full: 9999px;
  --md-corner-large: 24px;
  --md-corner-medium: 16px;
  --md-corner-small: 12px;

  --md-elevation-1: 0px 2px 6px rgba(0, 0, 0, 0.4);
  --md-elevation-2: 0px 4px 12px rgba(0, 0, 0, 0.5), 0px 1px 3px rgba(0, 0, 0, 0.3);
  --md-elevation-3: 0px 8px 24px rgba(0, 0, 0, 0.6), 0px 2px 6px rgba(0, 0, 0, 0.4);

  /* Fonts */
  --font-family-sans: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-mono: 'Roboto Mono', monospace;

  /* Animation transitions */
  --transition-fast: 0.15s cubic-bezier(0.2, 0, 0, 1);
  --transition-normal: 0.25s cubic-bezier(0.2, 0, 0, 1);
  --transition-bounce: 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* Light Theme Theme Variant */
[data-theme="light"] {
  --md-sys-color-background: #f8f9ff;
  --md-sys-color-on-background: #191c22;
  --md-sys-color-surface: #ffffff;
  --md-sys-color-surface-dim: #dedfe6;
  --md-sys-color-surface-container: #f0f3fc;
  --md-sys-color-surface-container-high: #e2e7f3;
  --md-sys-color-surface-container-highest: #d4daf0;
  --md-sys-color-on-surface: #191c22;
  --md-sys-color-on-surface-variant: #424754;
  --md-sys-color-outline: #727785;
  --md-sys-color-outline-variant: #c2c6d6;

  --md-sys-color-primary: #1b56ce;
  --md-sys-color-on-primary: #ffffff;
  --md-sys-color-primary-container: #d9e2ff;
  --md-sys-color-on-primary-container: #001946;

  --md-sys-color-secondary: #006b5b;
  --md-sys-color-on-secondary: #ffffff;
  --md-sys-color-secondary-container: #70f7d9;
  --md-sys-color-on-secondary-container: #00201a;

  --md-sys-color-tertiary: #9b2447;
  --md-sys-color-on-tertiary: #ffffff;
  --md-sys-color-tertiary-container: #ffd9df;
  --md-sys-color-on-tertiary-container: #3f0013;

  --md-elevation-1: 0px 2px 6px rgba(0, 0, 0, 0.08);
  --md-elevation-2: 0px 4px 16px rgba(0, 0, 0, 0.12);
  --md-elevation-3: 0px 12px 32px rgba(0, 0, 0, 0.16);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}

body {
  font-family: var(--font-family-sans);
  background-color: var(--md-sys-color-background);
  color: var(--md-sys-color-on-background);
  min-height: 100vh;
  min-height: -webkit-fill-available;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow-x: hidden;
  padding: 0;
  transition: background-color var(--transition-normal);
}

html {
  height: -webkit-fill-available;
}

/* Main Container Layout */
.app-viewport {
  width: 100%;
  max-width: 440px;
  height: 100vh;
  max-height: 920px;
  display: flex;
  flex-direction: column;
  background-color: var(--md-sys-color-surface);
  position: relative;
  overflow: hidden;
  box-shadow: var(--md-elevation-3);
  border-radius: 0;
}

@media (min-width: 480px) {
  .app-viewport {
    height: 92vh;
    border-radius: var(--md-corner-large);
    border: 1px solid var(--md-sys-color-outline-variant);
  }
}

/* Header Bar */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  background-color: var(--md-sys-color-surface);
  z-index: 10;
}

.brand-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  color: var(--md-sys-color-on-surface);
}

.brand-badge {
  background: linear-gradient(135deg, var(--md-sys-color-primary), var(--md-sys-color-secondary));
  color: #000;
  font-size: 0.7rem;
  font-weight: 800;
  padding: 2px 8px;
  border-radius: var(--md-corner-full);
  text-transform: uppercase;
  letter-spacing: 0.8px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.icon-btn {
  background: transparent;
  border: none;
  color: var(--md-sys-color-on-surface-variant);
  width: 40px;
  height: 40px;
  border-radius: var(--md-corner-full);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background-color var(--transition-fast), color var(--transition-fast), transform var(--transition-bounce);
  position: relative;
  overflow: hidden;
}

.icon-btn:hover {
  background-color: var(--md-sys-color-surface-container-high);
  color: var(--md-sys-color-on-surface);
}

.icon-btn:active {
  transform: scale(0.92);
}

.icon-btn svg {
  width: 22px;
  height: 22px;
  fill: currentColor;
}

/* Display Screen Section */
.display-section {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 16px 24px;
  background-color: var(--md-sys-color-surface-dim);
  border-bottom-left-radius: var(--md-corner-large);
  border-bottom-right-radius: var(--md-corner-large);
  position: relative;
  margin: 0 12px;
  border: 1px solid var(--md-sys-color-outline-variant);
}

.active-mode-badge {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background-color: var(--md-sys-color-primary-container);
  color: var(--md-sys-color-on-primary-container);
  font-size: 0.825rem;
  font-weight: 600;
  border-radius: var(--md-corner-full);
  margin-bottom: 8px;
  transition: all var(--transition-normal);
  animation: fadeIn 0.3s ease-in-out;
}

.active-mode-badge.pulse {
  animation: badgePulse 0.4s ease-out;
}

@keyframes badgePulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.06); }
  100% { transform: scale(1); }
}

.expression-line {
  font-family: var(--font-family-mono);
  font-size: 1rem;
  color: var(--md-sys-color-on-surface-variant);
  min-height: 24px;
  text-align: right;
  word-break: break-all;
  opacity: 0.85;
  margin-bottom: 6px;
  transition: color var(--transition-fast);
}

.primary-display {
  font-family: var(--font-family-sans);
  font-weight: 600;
  text-align: right;
  color: var(--md-sys-color-on-surface);
  line-height: 1.1;
  word-break: break-all;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: font-size var(--transition-fast), color var(--transition-fast);
}

.primary-display.size-lg { font-size: 3.25rem; }
.primary-display.size-md { font-size: 2.5rem; }
.primary-display.size-sm { font-size: 1.85rem; }
.primary-display.size-xs { font-size: 1.4rem; }

.sub-result-line {
  font-size: 0.9rem;
  color: var(--md-sys-color-secondary);
  font-weight: 500;
  text-align: right;
  min-height: 22px;
  margin-top: 4px;
}

/* Express Percentage Controls (Mode Bar) */
.controls-section {
  padding: 12px 16px 4px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.section-label {
  font-size: 0.725rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--md-sys-color-on-surface-variant);
  margin-left: 4px;
}

.express-modes-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.mode-chip {
  background-color: var(--md-sys-color-surface-container);
  border: 1px solid var(--md-sys-color-outline-variant);
  color: var(--md-sys-color-on-surface);
  padding: 10px 4px;
  border-radius: var(--md-corner-medium);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.mode-chip .chip-sub {
  font-size: 0.65rem;
  opacity: 0.75;
  font-weight: 400;
}

.mode-chip:hover {
  background-color: var(--md-sys-color-surface-container-high);
}

.mode-chip.active {
  background-color: var(--md-sys-color-primary-container);
  color: var(--md-sys-color-on-primary-container);
  border-color: var(--md-sys-color-primary);
  box-shadow: 0 0 12px rgba(120, 160, 255, 0.25);
  transform: translateY(-1px);
}

/* Quick Percentage Presets Bar */
.presets-scroll {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding: 2px 0 6px 0;
  scrollbar-width: none;
}
.presets-scroll::-webkit-scrollbar { display: none; }

.preset-pill {
  background-color: var(--md-sys-color-surface-container-high);
  border: 1px solid transparent;
  color: var(--md-sys-color-on-surface);
  padding: 6px 14px;
  border-radius: var(--md-corner-full);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.preset-pill:hover {
  background-color: var(--md-sys-color-surface-container-highest);
}

.preset-pill:active {
  transform: scale(0.95);
  background-color: var(--md-sys-color-secondary-container);
  color: var(--md-sys-color-on-secondary-container);
}

/* Keypad Section */
.keypad-section {
  padding: 8px 16px 16px 16px;
  flex-shrink: 0;
}

.keypad-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.key-btn {
  background-color: var(--md-sys-color-surface-container);
  color: var(--md-sys-color-on-surface);
  border: none;
  border-radius: var(--md-corner-large);
  height: 58px;
  font-size: 1.45rem;
  font-weight: 500;
  font-family: var(--font-family-sans);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--transition-fast), transform 0.08s ease, box-shadow var(--transition-fast);
  position: relative;
  overflow: hidden;
  box-shadow: var(--md-elevation-1);
}

.key-btn:hover {
  background-color: var(--md-sys-color-surface-container-high);
}

.key-btn:active, .key-btn.pressed {
  transform: scale(0.93);
  box-shadow: none;
}

/* Key Variant Styling */
.key-btn.action-key {
  background-color: var(--md-sys-color-surface-container-highest);
  color: var(--md-sys-color-tertiary);
  font-weight: 600;
}

.key-btn.operator-key {
  background-color: var(--md-sys-color-surface-container-highest);
  color: var(--md-sys-color-primary);
  font-size: 1.6rem;
}

.key-btn.operator-key.active {
  background-color: var(--md-sys-color-primary);
  color: var(--md-sys-color-on-primary);
}

.key-btn.equals-key {
  background: linear-gradient(135deg, var(--md-sys-color-primary), var(--md-sys-color-secondary));
  color: #000000;
  font-weight: 700;
  font-size: 1.75rem;
  box-shadow: 0 4px 14px rgba(0, 214, 181, 0.3);
}

.key-btn.equals-key:hover {
  filter: brightness(1.1);
}

/* Ripple Touch Effect */
.ripple {
  position: absolute;
  border-radius: 50%;
  transform: scale(0);
  animation: rippleAnimation 0.4s linear;
  background-color: rgba(255, 255, 255, 0.35);
  pointer-events: none;
}

@keyframes rippleAnimation {
  to {
    transform: scale(4);
    opacity: 0;
  }
}

/* History Tape Drawer Sheet */
.history-drawer {
  position: absolute;
  inset: 0;
  background-color: var(--md-sys-color-surface);
  z-index: 100;
  display: flex;
  flex-direction: column;
  transform: translateY(100%);
  transition: transform var(--transition-normal);
}

.history-drawer.open {
  transform: translateY(0);
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--md-sys-color-outline-variant);
}

.drawer-title {
  font-size: 1.15rem;
  font-weight: 700;
}

.history-list {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.history-empty {
  text-align: center;
  color: var(--md-sys-color-on-surface-variant);
  margin: auto;
  font-size: 0.95rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.history-item {
  background-color: var(--md-sys-color-surface-container);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--md-corner-medium);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.history-item:hover {
  background-color: var(--md-sys-color-surface-container-high);
  border-color: var(--md-sys-color-primary);
}

.history-item .history-expr {
  font-family: var(--font-family-mono);
  font-size: 0.85rem;
  color: var(--md-sys-color-on-surface-variant);
}

.history-item .history-res {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--md-sys-color-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.history-item .history-badge {
  font-size: 0.7rem;
  padding: 2px 8px;
  border-radius: var(--md-corner-full);
  background-color: var(--md-sys-color-surface-container-highest);
  color: var(--md-sys-color-on-surface);
}

.drawer-footer {
  padding: 14px 20px;
  border-top: 1px solid var(--md-sys-color-outline-variant);
  display: flex;
  gap: 10px;
}

.text-btn {
  flex: 1;
  background: transparent;
  border: 1px solid var(--md-sys-color-outline);
  color: var(--md-sys-color-on-surface);
  padding: 10px;
  border-radius: var(--md-corner-full);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  transition: background-color var(--transition-fast);
}

.text-btn:hover {
  background-color: var(--md-sys-color-surface-container-high);
}

.text-btn.danger {
  color: var(--md-sys-color-error);
  border-color: var(--md-sys-color-error);
}

/* Toast Notifications */
.toast-container {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--md-sys-color-inverse-surface, #e1e2e8);
  color: var(--md-sys-color-inverse-on-surface, #191c22);
  padding: 10px 20px;
  border-radius: var(--md-corner-full);
  font-size: 0.85rem;
  font-weight: 600;
  box-shadow: var(--md-elevation-2);
  z-index: 200;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-fast), transform var(--transition-fast);
}

.toast-container.show {
  opacity: 1;
  transform: translateX(-50%) translateY(-10px);
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}