/* =========================================================
   QR Code Studio - Design System & Modern Styles
   ========================================================= */

:root {
  --font-display: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Color Palette */
  --bg-base: #090d16;
  --bg-surface: rgba(18, 24, 38, 0.75);
  --bg-surface-elevated: rgba(28, 36, 56, 0.85);
  --bg-input: rgba(13, 18, 30, 0.8);
  
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-focus: #6366f1;
  --border-glow: rgba(99, 102, 241, 0.35);

  --accent-primary: #6366f1;
  --accent-primary-hover: #4f46e5;
  --accent-secondary: #06b6d4;
  --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #d946ef 100%);
  --accent-gradient-subtle: linear-gradient(135deg, rgba(99, 102, 241, 0.15), rgba(139, 92, 246, 0.15));

  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --success: #10b981;
  --success-glow: rgba(16, 185, 129, 0.3);
  --danger: #ef4444;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;

  --shadow-card: 0 20px 40px -15px rgba(0, 0, 0, 0.5), 0 0 0 1px var(--border-subtle);
  --shadow-glow: 0 10px 30px -5px rgba(99, 102, 241, 0.35);
  --shadow-preview: 0 15px 35px rgba(0, 0, 0, 0.4);

  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

body {
  font-family: var(--font-body);
  background-color: var(--bg-base);
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(99, 102, 241, 0.12) 0%, transparent 40%),
    radial-gradient(circle at 85% 85%, rgba(217, 70, 239, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 50% 50%, rgba(6, 182, 212, 0.05) 0%, transparent 60%);
  background-attachment: fixed;
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.app-wrapper {
  max-width: 1280px;
  margin: 0 auto;
  padding: 1.5rem 2rem;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  gap: 1.5rem;
}

/* App Header */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  background: var(--bg-surface);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
}

.brand-group {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.brand-icon {
  width: 44px;
  height: 44px;
  background: var(--accent-gradient);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.brand-icon svg {
  width: 26px;
  height: 26px;
}

.brand-text h1 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #ffffff 40%, #cbd5e1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.privacy-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--success);
  background: rgba(16, 185, 129, 0.1);
  padding: 2px 8px;
  border-radius: 999px;
  border: 1px solid rgba(16, 185, 129, 0.2);
}

.pulse-dot {
  width: 6px;
  height: 6px;
  background-color: var(--success);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--success);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

/* Main Grid Layout */
.main-layout {
  display: grid;
  grid-template-columns: 1.25fr 0.95fr;
  gap: 1.5rem;
  align-items: start;
}

/* Cards */
.card {
  background: var(--bg-surface);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-card);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

/* Tab Navigation */
.mode-tabs {
  display: flex;
  gap: 0.4rem;
  background: var(--bg-input);
  padding: 0.4rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  margin-bottom: 1.5rem;
  overflow-x: auto;
}

.tab-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 0.85rem;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-family: var(--font-display);
  font-size: 0.88rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.tab-btn svg {
  width: 17px;
  height: 17px;
  transition: transform var(--transition-fast);
}

.tab-btn:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.04);
}

.tab-btn.active {
  background: var(--accent-gradient);
  color: #ffffff;
  font-weight: 600;
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.35);
}

.tab-btn.active svg {
  transform: scale(1.08);
}

/* Forms */
.form-body {
  margin-bottom: 1.5rem;
}

.panel-form {
  display: none;
  animation: fadeIn 0.25s ease-out forwards;
}

.panel-form.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

.form-header {
  margin-bottom: 1.25rem;
}

.form-header h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text-primary);
}

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

.input-group {
  margin-bottom: 1.15rem;
}

.input-group label,
.label-with-action label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 0.45rem;
}

.label-with-action {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.char-count {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
}

.req {
  color: var(--accent-primary);
}

.optional {
  color: var(--text-muted);
  font-size: 0.78rem;
  font-weight: 400;
}

.input-with-icon {
  position: relative;
  display: flex;
  align-items: center;
}

.input-with-icon svg {
  position: absolute;
  left: 14px;
  width: 18px;
  height: 18px;
  color: var(--text-muted);
  pointer-events: none;
  transition: color var(--transition-fast);
}

.input-with-icon input {
  padding-left: 42px !important;
}

.input-with-icon:focus-within svg {
  color: var(--accent-primary);
}

input[type="text"],
input[type="email"],
input[type="tel"],
input[type="url"],
input[type="password"],
textarea,
select {
  width: 100%;
  padding: 0.75rem 1rem;
  background: var(--bg-input);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  outline: none;
  transition: all var(--transition-fast);
}

input:focus,
textarea:focus,
select:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--border-glow);
  background: rgba(18, 24, 40, 0.95);
}

textarea {
  resize: vertical;
  min-height: 80px;
}

.input-hint {
  display: block;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.35rem;
}

/* Domain Pills & Shortcuts */
.domain-pills,
.protocol-shortcuts {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.5rem;
}

.pill-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-right: 2px;
}

.domain-pill,
.btn-chip {
  padding: 0.25rem 0.6rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  border-radius: 999px;
  color: var(--text-secondary);
  font-size: 0.75rem;
  font-family: var(--font-mono);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.domain-pill:hover,
.btn-chip:hover {
  background: var(--accent-gradient-subtle);
  border-color: var(--accent-primary);
  color: #ffffff;
}

/* Toggle Switch */
.toggle-switch-container {
  display: flex;
  background: var(--bg-input);
  padding: 3px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  margin-bottom: 1.25rem;
}

.toggle-option {
  flex: 1;
  text-align: center;
  cursor: pointer;
}

.toggle-option input[type="radio"] {
  display: none;
}

.toggle-pill {
  display: block;
  padding: 0.5rem 0.75rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.toggle-option input[type="radio"]:checked + .toggle-pill {
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  font-weight: 600;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-subtle);
}

/* Password wrapper */
.password-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.password-wrapper input {
  padding-right: 44px;
}

.btn-icon-addon {
  position: absolute;
  right: 10px;
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.btn-icon-addon:hover {
  color: var(--text-primary);
}

.btn-icon-addon svg {
  width: 18px;
  height: 18px;
}

/* Form Row & Checkbox */
.form-row {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.flex-1 {
  flex: 1;
}

.checkbox-group {
  padding-top: 10px;
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.checkbox-label input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--accent-primary);
}

/* Customizer Details */
.customizer-details {
  border-top: 1px solid var(--border-subtle);
  padding-top: 1.25rem;
  margin-top: auto;
}

.customizer-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  list-style: none;
  user-select: none;
  padding: 0.25rem 0;
}

.customizer-summary::-webkit-details-marker {
  display: none;
}

.summary-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.chevron {
  font-size: 0.7rem;
  color: var(--text-muted);
  transition: transform var(--transition-fast);
}

.customizer-details[open] .chevron {
  transform: rotate(180deg);
}

.customizer-body {
  padding-top: 1.25rem;
}

.palette-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.sub-label {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.theme-chips {
  display: flex;
  gap: 0.5rem;
}

.theme-chip {
  width: 26px;
  height: 26px;
  border-radius: 50%;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform var(--transition-fast);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}

.theme-chip:hover {
  transform: scale(1.15);
}

.theme-chip.active {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 2px var(--border-glow);
}

.theme-chip[data-fg="#000000"] { background: #ffffff; }
.theme-chip[data-fg="#1e1b4b"] { background: #cbd5e1; }
.theme-chip[data-fg="#4338ca"] { background: #818cf8; }
.theme-chip[data-fg="#047857"] { background: #34d399; }
.theme-chip[data-fg="#be185d"] { background: #f472b6; }
.theme-chip[data-fg="#ffffff"] { background: #1e293b; border-color: rgba(255,255,255,0.3); }

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

.color-picker-wrapper {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--bg-input);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 0.35rem 0.6rem;
}

input[type="color"] {
  -webkit-appearance: none;
  border: none;
  width: 28px;
  height: 28px;
  border-radius: 6px;
  cursor: pointer;
  background: transparent;
}

input[type="color"]::-webkit-color-swatch-wrapper {
  padding: 0;
}

input[type="color"]::-webkit-color-swatch {
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 6px;
}

.hex-label {
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: var(--text-secondary);
}

/* Preview Card */
.preview-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  text-align: center;
}

.preview-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  margin-bottom: 1.5rem;
}

.preview-header h2 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.badge-tag {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--accent-gradient-subtle);
  color: var(--accent-primary);
  border: 1px solid rgba(99, 102, 241, 0.3);
}

/* Canvas Display Frame */
.canvas-display-frame {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  margin-bottom: 1.5rem;
}

.canvas-wrapper {
  background: #ffffff;
  padding: 18px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-preview);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-normal);
  max-width: 100%;
}

.canvas-wrapper:hover {
  transform: translateY(-2px);
}

#qr-canvas {
  display: block;
  max-width: 100%;
  height: auto;
  border-radius: 4px;
}

.preview-raw-text {
  max-width: 320px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-size: 0.78rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  margin-top: 0.75rem;
  padding: 0.25rem 0.6rem;
  background: rgba(0, 0, 0, 0.2);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
}

/* Action Buttons */
.action-buttons-group {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 0.7rem 1.25rem;
  font-family: var(--font-display);
  font-size: 0.92rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
}

.btn svg {
  width: 18px;
  height: 18px;
}

.btn-primary {
  background: var(--accent-gradient);
  color: #ffffff;
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  filter: brightness(1.1);
  transform: translateY(-1px);
  box-shadow: 0 12px 28px -4px rgba(99, 102, 241, 0.5);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-large {
  padding: 0.9rem 1.5rem;
  font-size: 1rem;
}

.btn-secondary {
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  border: 1px solid var(--border-subtle);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid transparent;
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-primary);
}

.download-row {
  display: flex;
  gap: 0.75rem;
}

.export-options-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding-top: 0.4rem;
  border-top: 1px solid var(--border-subtle);
}

.export-size-label {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.select-small {
  padding: 0.35rem 0.6rem;
  font-size: 0.8rem;
  width: auto;
  border-radius: var(--radius-sm);
}

/* Security Banner */
.security-banner {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 0.85rem 1rem;
  background: rgba(99, 102, 241, 0.05);
  border: 1px solid rgba(99, 102, 241, 0.15);
  border-radius: var(--radius-md);
  text-align: left;
  width: 100%;
}

.sec-icon {
  color: var(--accent-primary);
  flex-shrink: 0;
  margin-top: 2px;
}

.sec-icon svg {
  width: 18px;
  height: 18px;
}

.sec-text strong {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-primary);
}

.sec-text p {
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-top: 2px;
}

/* Footer */
.app-footer {
  text-align: center;
  padding: 1rem 0;
  font-size: 0.8rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-subtle);
}

/* Toast */
.toast {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background: #1e293b;
  border: 1px solid rgba(255, 255, 255, 0.15);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.6);
  border-radius: var(--radius-md);
  padding: 0.85rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: #ffffff;
  font-size: 0.9rem;
  font-weight: 500;
  opacity: 0;
  transform: translateY(20px) scale(0.95);
  pointer-events: none;
  transition: all var(--transition-normal);
  z-index: 1000;
}

.toast.show {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: auto;
}

.toast-icon {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--success);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.75rem;
}

.toast.error .toast-icon {
  background: var(--danger);
}

/* Helpers */
.hidden {
  display: none !important;
}

/* Responsive */
@media (max-width: 900px) {
  .main-layout {
    grid-template-columns: 1fr;
  }
  .app-wrapper {
    padding: 1rem;
  }
}

/* Print Styles */
@media print {
  body {
    background: #ffffff !important;
    color: #000000 !important;
  }
  .app-header,
  .input-card,
  .action-buttons-group,
  .security-banner,
  .app-footer,
  .toast {
    display: none !important;
  }
  .preview-card {
    border: none !important;
    box-shadow: none !important;
    background: transparent !important;
    padding: 0 !important;
  }
  .canvas-wrapper {
    box-shadow: none !important;
    border: none !important;
    padding: 0 !important;
  }
  .canvas-display-frame {
    margin: 40px auto;
  }
  #qr-canvas {
    width: 300px !important;
    height: 300px !important;
  }
}