/* Import elegant fonts from Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;500;600;700;800&display=swap');

:root {
  --bg-primary: #0b0f19;
  --bg-secondary: #111827;
  --bg-tertiary: #1f2937;
  
  --accent-primary: #6366f1; /* Indigo */
  --accent-secondary: #a855f7; /* Violet */
  --accent-cyan: #06b6d4; /* Cyan */
  
  --text-primary: #f3f4f6;
  --text-secondary: #9ca3af;
  --text-muted: #6b7280;
  
  --color-success: #10b981; /* Emerald */
  --color-warning: #f59e0b; /* Amber */
  --color-error: #ef4444; /* Red */
  
  --font-heading: 'Outfit', 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;
  
  --card-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
  --border-glass: 1px solid rgba(255, 255, 255, 0.08);
  --bg-glass: rgba(17, 24, 39, 0.7);
  --bg-glass-hover: rgba(31, 41, 55, 0.85);
  
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Base Reset & Styling */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-body);
  line-height: 1.6;
  overflow-x: hidden;
  min-height: 100vh;
  background-image: 
    radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.15) 0px, transparent 50%),
    radial-gradient(at 100% 100%, rgba(168, 85, 247, 0.15) 0px, transparent 50%),
    radial-gradient(at 50% 50%, rgba(6, 182, 212, 0.05) 0px, transparent 50%);
  background-attachment: fixed;
}

/* Header & Navigation */
header {
  padding: 1.5rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: var(--border-glass);
  background: rgba(11, 15, 25, 0.5);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo-container {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo-icon {
  width: 2.5rem;
  height: 2.5rem;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  border-radius: 0.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-family: var(--font-heading);
  font-size: 1.25rem;
  box-shadow: 0 0 15px rgba(99, 102, 241, 0.4);
}

.logo-text h1 {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 700;
  background: linear-gradient(to right, #ffffff, var(--text-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-text p {
  font-size: 0.75rem;
  color: var(--accent-cyan);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.lang-toggle {
  background: rgba(255, 255, 255, 0.05);
  border: var(--border-glass);
  padding: 0.5rem 1rem;
  border-radius: 2rem;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition-fast);
}

.lang-toggle:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--accent-cyan);
  box-shadow: 0 0 10px rgba(6, 182, 212, 0.2);
}

/* App Main Layout */
.app-container {
  max-width: 1400px;
  margin: 2rem auto;
  padding: 0 1.5rem;
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 2rem;
}

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

/* Sidebar / Controls Panel */
.controls-panel {
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: var(--border-glass);
  border-radius: 1.25rem;
  padding: 1.75rem;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  height: fit-content;
  position: sticky;
  top: 6rem;
}

.panel-title {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  font-weight: 600;
  border-left: 4px solid var(--accent-cyan);
  padding-left: 0.75rem;
  margin-bottom: 0.5rem;
}

/* Form Styling */
.control-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.control-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.control-value-badge {
  color: var(--accent-cyan);
  font-weight: 700;
  font-family: var(--font-heading);
}

/* Input Fields and Custom Range */
.input-number {
  background: rgba(255, 255, 255, 0.05);
  border: var(--border-glass);
  padding: 0.75rem 1rem;
  border-radius: 0.75rem;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  width: 100%;
  transition: var(--transition-fast);
}

.input-number:focus {
  outline: none;
  background: rgba(255, 255, 255, 0.08);
  border-color: var(--accent-primary);
  box-shadow: 0 0 12px rgba(99, 102, 241, 0.25);
}

input[type="range"] {
  -webkit-appearance: none;
  width: 100%;
  height: 6px;
  border-radius: 3px;
  background: rgba(255, 255, 255, 0.1);
  outline: none;
  margin: 0.75rem 0;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  cursor: pointer;
  box-shadow: 0 0 8px rgba(99, 102, 241, 0.6);
  transition: transform 0.1s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

/* Custom Tabs / Toggles */
.tab-group {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: rgba(255, 255, 255, 0.04);
  border: var(--border-glass);
  padding: 0.25rem;
  border-radius: 0.75rem;
  margin-bottom: 0.5rem;
}

.tab-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  padding: 0.6rem;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  border-radius: 0.5rem;
  transition: var(--transition-fast);
}

.tab-btn.active {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  color: var(--text-primary);
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

/* Main Display Dashboard */
.dashboard {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

/* Status Banner */
.status-banner {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.2);
  border-radius: 1rem;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  box-shadow: 0 4px 15px rgba(16, 185, 129, 0.05);
}

.status-banner.error {
  background: rgba(239, 68, 68, 0.1);
  border-color: rgba(239, 68, 68, 0.2);
  box-shadow: 0 4px 15px rgba(239, 68, 68, 0.05);
}

.status-icon {
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 50%;
  background: rgba(16, 185, 129, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-success);
  font-size: 1.25rem;
  flex-shrink: 0;
}

.status-banner.error .status-icon {
  background: rgba(239, 68, 68, 0.2);
  color: var(--color-error);
}

.status-info h3 {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 600;
}

.status-info p {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

/* Visualization Panel */
.visualizer-card {
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: var(--border-glass);
  border-radius: 1.25rem;
  padding: 1.5rem;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.canvas-container {
  width: 100%;
  aspect-ratio: 1.35;
  background: #07090e;
  border-radius: 1rem;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.04);
  position: relative;
}

canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.canvas-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.btn-icon {
  background: rgba(255, 255, 255, 0.05);
  border: var(--border-glass);
  color: var(--text-primary);
  padding: 0.6rem 1.2rem;
  border-radius: 0.75rem;
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition-fast);
}

.btn-icon:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--accent-primary);
}

.btn-icon.active {
  background: rgba(99, 102, 241, 0.2);
  border-color: var(--accent-primary);
  color: #c7d2fe;
}

/* Output Cards Grid */
.output-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.25rem;
}

.output-card {
  background: rgba(255, 255, 255, 0.02);
  border: var(--border-glass);
  border-radius: 1rem;
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  position: relative;
  overflow: hidden;
  transition: var(--transition-normal);
}

.output-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--accent-primary);
}

.output-card.cyan::after {
  background: var(--accent-cyan);
}

.output-card.emerald::after {
  background: var(--color-success);
}

.output-card.amber::after {
  background: var(--color-warning);
}

.output-card:hover {
  background: rgba(255, 255, 255, 0.04);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.output-card-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.output-card-value {
  font-family: var(--font-heading);
  font-size: 1.85rem;
  font-weight: 700;
  color: var(--text-primary);
}

.output-card-unit {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-left: 0.25rem;
}

/* Math Explanation & Vector Proof Section */
.proof-section {
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: var(--border-glass);
  border-radius: 1.25rem;
  padding: 2rem;
  box-shadow: var(--card-shadow);
}

.section-header {
  margin-bottom: 1.5rem;
}

.section-header h2 {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 700;
  background: linear-gradient(to right, #ffffff, var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-header p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
}

/* Math Formula Displays */
.formula-box {
  background: rgba(0, 0, 0, 0.3);
  border: 1px dashed rgba(255, 255, 255, 0.08);
  border-radius: 0.75rem;
  padding: 1.25rem;
  margin: 1rem 0;
  font-family: 'Courier New', Courier, monospace;
  font-size: 0.95rem;
  overflow-x: auto;
  color: #c7d2fe;
}

.proof-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

@media (max-width: 768px) {
  .proof-grid {
    grid-template-columns: 1fr;
  }
}

.proof-col h3 {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.75rem;
}

.proof-col p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.proof-list {
  list-style: none;
}

.proof-list li {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
  position: relative;
  padding-left: 1.25rem;
}

.proof-list li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--accent-cyan);
  font-weight: bold;
}

.code-inline {
  background: rgba(255, 255, 255, 0.08);
  padding: 0.15rem 0.4rem;
  border-radius: 0.25rem;
  font-family: monospace;
  font-size: 0.85rem;
  color: var(--accent-cyan);
}

/* Footer Section */
footer {
  text-align: center;
  padding: 2.5rem 1rem;
  color: var(--text-muted);
  font-size: 0.8rem;
  border-top: var(--border-glass);
  background: rgba(7, 9, 14, 0.4);
  margin-top: 4rem;
}

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

footer a:hover {
  color: var(--accent-cyan);
}

/* CAD & CNC Exporter Custom Styles */
.card-header-with-action {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn-icon.outline {
  border-color: rgba(255, 255, 255, 0.15);
  background: transparent;
}

.btn-icon.outline:hover, .btn-icon.outline.active {
  border-color: var(--accent-cyan);
  background: rgba(6, 182, 212, 0.1);
  color: var(--accent-cyan);
}

.btn-icon.glow-cyan {
  background: rgba(6, 182, 212, 0.15);
  border-color: var(--accent-cyan);
  color: #e0f7fa;
  box-shadow: 0 0 10px rgba(6, 182, 212, 0.2);
}

.btn-icon.glow-cyan:hover {
  background: rgba(6, 182, 212, 0.3);
  box-shadow: 0 0 15px rgba(6, 182, 212, 0.45);
}

.table-container th, .table-container td {
  padding: 0.5rem 0.75rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.table-container tr:hover td {
  background: rgba(255, 255, 255, 0.03);
}

.table-container::-webkit-scrollbar {
  width: 6px;
}

.table-container::-webkit-scrollbar-track {
  background: rgba(0, 0, 0, 0.2);
}

.table-container::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.15);
  border-radius: 3px;
}