/*
 * style.css
 *
 * Refactored OLED Black Design System for the Standard Model Lagrangian Density Explorer.
 * Features a pure black (#000000) OLED theme, inline-wrapping flex equations that flow
 * exactly like a textbook paragraph, and full responsive phone optimizations.
 */

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

:root {
  /* HSL Color System - OLED Pure Black */
  --bg-deep: #000000;
  --bg-card: rgba(8, 10, 15, 0.75);
  --bg-card-hover: rgba(16, 20, 30, 0.85);
  --border-glass: rgba(255, 255, 255, 0.03);
  --border-glass-hover: rgba(255, 255, 255, 0.08);
  
  --text-main: hsl(210, 20%, 98%);
  --text-muted: hsl(215, 14%, 68%);
  --text-dark: hsl(215, 12%, 40%);
  
  /* Sector Accent Colors */
  --color-gauge: hsl(195, 100%, 50%);    /* Glowing cyan */
  --color-higgs: hsl(280, 100%, 65%);    /* Glowing violet */
  --color-fermion: hsl(140, 100%, 60%);  /* Glowing green */
  --color-yukawa: hsl(38, 100%, 55%);    /* Glowing amber */
  --color-ghosts: hsl(350, 100%, 60%);   /* Glowing coral */
  
  /* System glows */
  --glow-gauge: rgba(0, 212, 255, 0.25);
  --glow-higgs: rgba(180, 0, 255, 0.25);
  --glow-fermion: rgba(0, 255, 100, 0.25);
  --glow-yukawa: rgba(255, 150, 0, 0.25);
  --glow-ghosts: rgba(255, 0, 50, 0.25);
  
  /* Default active theme color (starts with cyan) */
  --color-active: var(--color-gauge);
  --glow-active: var(--glow-gauge);
  
  /* Standard transition curve */
  --transition-smooth: all 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
  --transition-fast: all 0.15s ease;
}

/* Reset and Core Styles */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-deep);
  color: var(--text-main);
  font-family: 'Outfit', sans-serif;
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.5;
  background-image: 
    radial-gradient(circle at 10% 20%, rgba(0, 212, 255, 0.02) 0%, transparent 40%),
    radial-gradient(circle at 90% 80%, rgba(180, 0, 255, 0.02) 0%, transparent 40%),
    linear-gradient(rgba(255, 255, 255, 0.003) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.003) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 40px 40px, 40px 40px;
}

/* Custom Scrollbar Styles */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: rgba(0, 0, 0, 0.3);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.08);
  border-radius: 3px;
  border: 1px solid var(--bg-deep);
  transition: var(--transition-fast);
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* Typography & Headers */
h1, h2, h3, h4 {
  font-weight: 600;
  letter-spacing: -0.02em;
}

.text-gradient {
  background: linear-gradient(135deg, #ffffff 30%, #a5b4fc 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* App Layout */
.app-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 24px;
  min-height: 100vh;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(14px);
  border-radius: 16px;
  gap: 16px;
}

.header-left {
  display: flex;
  flex-direction: column;
}

.header-left h1 {
  font-size: 1.6rem;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}

.badge {
  font-family: 'Fira Code', monospace;
  font-size: 0.7rem;
  padding: 2px 8px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: var(--text-muted);
  white-space: nowrap;
}

.header-left p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 2px;
}

/* Interactive Controllers */
.controls-container {
  display: flex;
  align-items: center;
  gap: 16px;
}

.toggle-switch {
  display: flex;
  background: rgba(0, 0, 0, 0.5);
  padding: 4px;
  border-radius: 20px;
  border: 1px solid var(--border-glass);
}

.toggle-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  padding: 6px 16px;
  font-family: 'Outfit', sans-serif;
  font-size: 0.8rem;
  font-weight: 500;
  border-radius: 16px;
  cursor: pointer;
  transition: var(--transition-fast);
}

.toggle-btn.active {
  background: var(--text-main);
  color: var(--bg-deep);
  box-shadow: 0 4px 12px rgba(255, 255, 255, 0.15);
}

/* Category Filter Tabs */
.filter-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tab-btn {
  background: var(--bg-card);
  color: var(--text-muted);
  border: 1px solid var(--border-glass);
  padding: 8px 16px;
  border-radius: 20px;
  font-family: 'Outfit', sans-serif;
  font-size: 0.85rem;
  cursor: pointer;
  transition: var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 8px;
}

.tab-btn:hover {
  background: rgba(255, 255, 255, 0.02);
  border-color: rgba(255, 255, 255, 0.08);
  color: var(--text-main);
}

.tab-btn.active {
  color: var(--text-main);
}

.tab-btn.active[data-sector="all"] { border-color: var(--text-main); background: rgba(255, 255, 255, 0.08); }
.tab-btn.active[data-sector="gauge"] { border-color: var(--color-gauge); background: rgba(0, 212, 255, 0.08); text-shadow: 0 0 8px var(--glow-gauge); }
.tab-btn.active[data-sector="higgs"] { border-color: var(--color-higgs); background: rgba(180, 0, 255, 0.08); text-shadow: 0 0 8px var(--glow-higgs); }
.tab-btn.active[data-sector="fermion"] { border-color: var(--color-fermion); background: rgba(0, 255, 100, 0.08); text-shadow: 0 0 8px var(--glow-fermion); }
.tab-btn.active[data-sector="yukawa"] { border-color: var(--color-yukawa); background: rgba(255, 150, 0, 0.08); text-shadow: 0 0 8px var(--glow-yukawa); }
.tab-btn.active[data-sector="ghosts"] { border-color: var(--color-ghosts); background: rgba(255, 0, 50, 0.08); text-shadow: 0 0 8px var(--glow-ghosts); }

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--text-muted);
}
.tab-btn[data-sector="gauge"] .dot { background-color: var(--color-gauge); box-shadow: 0 0 6px var(--color-gauge); }
.tab-btn[data-sector="higgs"] .dot { background-color: var(--color-higgs); box-shadow: 0 0 6px var(--color-higgs); }
.tab-btn[data-sector="fermion"] .dot { background-color: var(--color-fermion); box-shadow: 0 0 6px var(--color-fermion); }
.tab-btn[data-sector="yukawa"] .dot { background-color: var(--color-yukawa); box-shadow: 0 0 6px var(--color-yukawa); }
.tab-btn[data-sector="ghosts"] .dot { background-color: var(--color-ghosts); box-shadow: 0 0 6px var(--color-ghosts); }

/* Unified Workspace Grid - Single Column Flow Stack */
.workspace-grid {
  display: flex;
  flex-direction: column;
  gap: 24px;
  width: 100%;
}

/* Formula Left Side Panel (Full Width) */
.formula-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(14px);
  border-radius: 16px;
  padding: 24px;
  width: 100%;
}

.panel-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-glass);
  padding-bottom: 12px;
}

.panel-header h2 {
  font-size: 1.15rem;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

.panel-header h2 svg {
  width: 18px;
  height: 18px;
  stroke: var(--text-muted);
}

#header-math {
  margin-left: 4px;
}

.search-input-wrapper {
  position: relative;
  width: 240px;
}

.search-input {
  width: 100%;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border-glass);
  padding: 6px 12px 6px 30px;
  border-radius: 8px;
  color: var(--text-main);
  font-family: 'Outfit', sans-serif;
  font-size: 0.85rem;
  outline: none;
  transition: var(--transition-fast);
}

.search-input:focus {
  border-color: rgba(255, 255, 255, 0.2);
  background: rgba(0, 0, 0, 0.6);
}

.search-icon {
  position: absolute;
  left: 10px;
  top: 50%;
  transform: translateY(-50%);
  width: 14px;
  height: 14px;
  fill: none;
  stroke: var(--text-muted);
}

/* Giant Equation Display Area (Renders math like a single flowing paragraph, shown in full) */
.lagrangian-display {
  width: 100%;
  padding: 16px 10px;
  background: rgba(255, 255, 255, 0.003);
  border: 1px solid rgba(255, 255, 255, 0.01);
  border-radius: 12px;
  
  /* Flex Wrapping and natural paragraph flow */
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-start;
  row-gap: 12px;
  column-gap: 2px;
  line-height: 2.2;
}

/* Master Equation Math Block wrapping each term in the paragraph flow */
.math-term-block {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 4px;
  margin: 1px 0;
  border-radius: 4px;
  background: transparent;
  border: 1px solid transparent;
  cursor: pointer;
  transition: var(--transition-smooth);
  user-select: text;
  position: relative;
  max-width: 100%;
}

/* Soft Dimming Overlay when sector is filtered */
.math-term-block.dimmed {
  opacity: 0.12;
  filter: blur(0.5px);
}

.math-term-block.filtered-out {
  display: none; /* Hide terms only on search query filtering */
}

.math-term-block:hover {
  background: var(--bg-card-hover);
  transform: scale(1.03);
  z-index: 10;
}

.math-term-block.active {
  background: rgba(255, 255, 255, 0.03);
  transform: scale(1.03);
  z-index: 10;
}

/* Sector-specific hover glowing borders */
.math-term-block[data-sector="gauge"]:hover,
.math-term-block[data-sector="gauge"].active {
  border-color: var(--color-gauge);
  box-shadow: 0 0 10px var(--glow-gauge), inset 0 0 2px var(--glow-gauge);
}

.math-term-block[data-sector="higgs"]:hover,
.math-term-block[data-sector="higgs"].active {
  border-color: var(--color-higgs);
  box-shadow: 0 0 10px var(--glow-higgs), inset 0 0 2px var(--glow-higgs);
}

.math-term-block[data-sector="fermion"]:hover,
.math-term-block[data-sector="fermion"].active {
  border-color: var(--color-fermion);
  box-shadow: 0 0 10px var(--glow-fermion), inset 0 0 2px var(--glow-fermion);
}

.math-term-block[data-sector="yukawa"]:hover,
.math-term-block[data-sector="yukawa"].active {
  border-color: var(--color-yukawa);
  box-shadow: 0 0 10px var(--glow-yukawa), inset 0 0 2px var(--glow-yukawa);
}

.math-term-block[data-sector="ghosts"]:hover,
.math-term-block[data-sector="ghosts"].active {
  border-color: var(--color-ghosts);
  box-shadow: 0 0 10px var(--glow-ghosts), inset 0 0 2px var(--glow-ghosts);
}

/* Sign indicator overlay dot */
.error-indicator-badge {
  position: absolute;
  top: 0px;
  right: 0px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background-color: var(--color-ghosts);
  box-shadow: 0 0 6px var(--color-ghosts);
}

/* Bottom Spaced Section - Split Panels Below Math */
.detail-column {
  width: 100%;
}

.details-split-container {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 20px;
  width: 100%;
  align-items: stretch;
}

@media (max-width: 1024px) {
  .details-split-container {
    grid-template-columns: 1fr;
  }
}

/* Explanations and Deconstructions Card (Left side) */
.details-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(14px);
  border-radius: 16px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  width: 100%;
}

/* Empty State */
.details-card.empty {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 36px;
  min-height: 180px;
}

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--text-dark);
  gap: 8px;
}

.empty-state svg {
  width: 44px;
  height: 44px;
  stroke: var(--text-dark);
  stroke-width: 1.5;
}

.empty-state h3 {
  color: var(--text-muted);
  font-size: 1.05rem;
}

.term-header {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.term-header .term-category {
  font-family: 'Fira Code', monospace;
  font-size: 0.75rem;
  text-transform: uppercase;
  color: var(--color-active);
  font-weight: 500;
  letter-spacing: 0.02em;
}

.term-header h3 {
  font-size: 1.25rem;
  color: var(--text-main);
}

/* Mobile-Proof Horizontal Math Scroller Card */
.term-math-block {
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.02);
  border-radius: 8px;
  padding: 12px;
  display: block;
  text-align: center;
  border-left: 3px solid var(--color-active);
  
  /* Prevent horizontal stretch overflows on phone */
  width: 100%;
  overflow-x: visible;
  overflow-y: visible;
}

.term-math-block .katex {
  white-space: normal !important;
  display: inline-block;
}

.term-math-block .base {
  padding-top: 3px;
  padding-bottom: 3px;
}

.term-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.correction-alert {
  background: rgba(255, 50, 80, 0.08);
  border: 1px solid rgba(255, 50, 80, 0.2);
  border-radius: 8px;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.correction-alert-header {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--color-ghosts);
  font-size: 0.85rem;
  font-weight: 600;
}

.correction-alert p {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.45;
}

/* Fields & Constants Tables */
.symbol-section {
  display: flex;
  flex-direction: column;
  gap: 8px;
  border-top: 1px solid var(--border-glass);
  padding-top: 14px;
}

.symbol-section h4 {
  font-size: 0.8rem;
  text-transform: uppercase;
  color: var(--text-muted);
  letter-spacing: 0.05em;
}

/* Responsive Pill Grid */
.symbol-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 8px;
}

.symbol-pill {
  background: rgba(255, 255, 255, 0.015);
  border: 1px solid var(--border-glass);
  padding: 6px 10px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: var(--transition-fast);
}

.symbol-pill:hover {
  background: rgba(255, 255, 255, 0.03);
  border-color: rgba(255, 255, 255, 0.1);
}

.symbol-math {
  font-size: 0.95rem;
  min-width: 22px;
  text-align: center;
}

.symbol-info {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.symbol-name {
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 90px;
}

.symbol-type {
  font-size: 0.6rem;
  color: var(--text-muted);
}

/* Physics Visualizer Panel (Canvas on the Right) */
.visualizer-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(14px);
  border-radius: 16px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 280px;
}

.visualizer-header {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-glass);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.visualizer-header h3 {
  font-size: 0.85rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.canvas-container {
  width: 100%;
  flex: 1;
  background: rgba(0, 0, 0, 0.4);
  position: relative;
}

#feynman-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

/* Side Encyclopedia Sliding Panel */
.encyclopedia-drawer {
  position: fixed;
  top: 0;
  right: -420px;
  width: 400px;
  height: 100vh;
  background: hsl(222, 28%, 4%);
  border-left: 1px solid var(--border-glass);
  box-shadow: -10px 0 30px rgba(0, 0, 0, 0.6);
  z-index: 1000;
  transition: transform 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
  display: flex;
  flex-direction: column;
  padding: 24px;
  backdrop-filter: blur(20px);
}

.encyclopedia-drawer.open {
  transform: translateX(-420px);
}

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

.drawer-header h3 {
  font-size: 1.2rem;
  color: var(--text-main);
}

.close-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.close-btn svg {
  width: 20px;
  height: 20px;
  stroke: var(--text-muted);
  transition: var(--transition-fast);
}

.close-btn:hover svg {
  stroke: var(--text-main);
  transform: rotate(90deg);
}

.drawer-content {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.encyclopedia-item {
  background: rgba(255, 255, 255, 0.01);
  border: 1px solid var(--border-glass);
  padding: 14px;
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

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

.item-symbol {
  font-size: 1.05rem;
  color: var(--color-gauge);
}

.item-badge {
  font-size: 0.6rem;
  padding: 2px 6px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-muted);
  font-family: 'Fira Code', monospace;
}

.encyclopedia-item h4 {
  font-size: 0.9rem;
  color: var(--text-main);
}

.encyclopedia-item p {
  font-size: 0.78rem;
  color: var(--text-muted);
  line-height: 1.45;
}

/* Floating Action Button to toggle Encyclopedia */
.floating-glossary-btn {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(12px);
  color: var(--text-main);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4), 0 0 10px rgba(255, 255, 255, 0.05);
  z-index: 99;
  transition: var(--transition-fast);
}

.floating-glossary-btn:hover {
  transform: translateY(-2px);
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.15);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.5), 0 0 15px rgba(255, 255, 255, 0.1);
}

.floating-glossary-btn svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: var(--text-main);
  stroke-width: 2;
}

/* Helper overlays */
.drawer-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  z-index: 999;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.drawer-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

/* Footer Section */
footer {
  text-align: center;
  padding: 16px 0;
  font-family: 'Fira Code', monospace;
  font-size: 0.72rem;
  color: var(--text-dark);
  border-top: 1px solid var(--border-glass);
  margin-top: auto;
}

footer a {
  color: var(--text-muted);
  text-decoration: none;
  transition: var(--transition-fast);
}

footer a:hover {
  color: var(--text-main);
  text-decoration: underline;
}

/* Custom Math and KaTeX overrides */
.katex-display {
  margin: 0 !important;
}

.katex {
  font-size: 1.04em;
}

/* Mobile Responsive System - Complete Spacing & Layout Optimization */
@media (max-width: 1024px) {
  .details-split-container {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  
  .visualizer-card {
    min-height: 250px;
    height: 250px;
  }
}

@media (max-width: 768px) {
  .app-container {
    padding: 12px 10px;
    gap: 16px;
  }

  header {
    flex-direction: column;
    align-items: flex-start;
    padding: 14px 16px;
    gap: 12px;
  }

  .header-left h1 {
    font-size: 1.3rem;
  }

  .header-left p {
    font-size: 0.78rem;
  }

  .controls-container {
    width: 100%;
    justify-content: space-between;
    gap: 8px;
  }

  .toggle-switch {
    width: auto;
  }

  .toggle-btn {
    padding: 4px 10px;
    font-size: 0.72rem;
  }

  .tab-btn {
    padding: 6px 12px;
    font-size: 0.76rem;
  }

  .panel-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .search-input-wrapper {
    width: 100%;
  }

  .formula-container {
    padding: 16px;
  }

  .lagrangian-display {
    padding: 12px 6px;
    row-gap: 8px;
    column-gap: 1px;
    line-height: 1.8;
  }

  .math-term-block {
    padding: 0 2px;
  }

  /* Make sure math equation wraps or scales down nicely on mobile screens */
  .lagrangian-display .katex {
    font-size: 0.82em;
  }

  .details-card {
    padding: 16px;
    gap: 12px;
  }

  .term-header h3 {
    font-size: 1.1rem;
  }

  .term-math-block {
    padding: 12px 8px;
  }

  .term-math-block .katex {
    font-size: 0.82em;
    white-space: normal !important;
  }

  .symbol-grid {
    grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
    gap: 6px;
  }

  .symbol-pill {
    padding: 4px 8px;
    gap: 6px;
  }

  .symbol-math {
    font-size: 0.8rem;
  }

  .symbol-name {
    font-size: 0.65rem;
    max-width: 70px;
  }

  .encyclopedia-drawer {
    width: 100%;
    right: -100%;
  }

  .encyclopedia-drawer.open {
    transform: translateX(-100%);
  }
}

@media (max-width: 480px) {
  .app-container {
    padding: 8px 6px;
    gap: 12px;
  }

  header {
    padding: 12px;
    border-radius: 12px;
  }

  .header-left h1 {
    font-size: 1.15rem;
    gap: 6px;
  }

  .controls-container {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .controls-container .badge {
    display: none; /* Hide non-critical labels on ultra-small screens */
  }

  .toggle-switch {
    width: 100%;
    justify-content: stretch;
  }

  .toggle-btn {
    flex: 1;
    text-align: center;
  }

  .filter-tabs {
    gap: 4px;
  }

  .tab-btn {
    padding: 5px 8px;
    font-size: 0.72rem;
    gap: 4px;
  }

  .formula-container {
    padding: 12px;
    border-radius: 12px;
  }

  .panel-header h2 {
    font-size: 0.95rem;
  }

  .lagrangian-display {
    padding: 8px 2px;
    line-height: 1.6;
  }

  .lagrangian-display .katex {
    font-size: 0.72em; /* Ensure all equation terms fit seamlessly on narrow viewports */
  }

  .details-card {
    padding: 12px;
    border-radius: 12px;
  }

  .visualizer-card {
    border-radius: 12px;
    height: 200px;
    min-height: 200px;
  }

  .term-math-block .katex {
    font-size: 0.72em;
  }

  .floating-glossary-btn {
    width: 44px;
    height: 44px;
    bottom: 16px;
    right: 16px;
  }

  .floating-glossary-btn svg {
    width: 18px;
    height: 18px;
  }
}