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

:root {
  --accent:        #3A55CC;
  --accent-dark:   #1C2F82;
  --gold:          #C9A227;
  --gold-dark:     #A07A18;
  --danger:        #DC2626;
  --success:       #16A34A;
  --text:          #1A1C2E;
  --text-muted:    #6B7280;
  --border:        #E2E6F5;
  --bg-page:       #F6F8FD;
  --bg-panel:      #FFFFFF;
  --header-bg:     #FFFFFF;
  --header-border: var(--accent);
  --header-text:   var(--accent);
  --radius:        8px;
  --shadow:        0 2px 8px rgba(58,85,204,0.08);
  --font:          'Inter', system-ui, sans-serif;
}

/* Dark theme — OS preference (when user hasn't manually chosen light) */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --text:          #E4E8F8;
    --text-muted:    #8892B0;
    --border:        #252845;
    --bg-page:       #0E1020;
    --bg-panel:      #181A30;
    --shadow:        0 2px 8px rgba(0,0,0,0.4);
    --header-bg:     #0A0D1F;
    --header-border: var(--gold);
    --header-text:   #E4E8F8;
  }
}

/* Dark theme — explicit user override */
[data-theme="dark"] {
  --text:          #E4E8F8;
  --text-muted:    #8892B0;
  --border:        #252845;
  --bg-page:       #0E1020;
  --bg-panel:      #181A30;
  --shadow:        0 2px 8px rgba(0,0,0,0.4);
  --header-bg:     #0A0D1F;
  --header-border: var(--gold);
  --header-text:   #E4E8F8;
}

html { font-size: 16px; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg-page);
  min-height: 100vh;
  line-height: 1.5;
}

a { color: var(--accent); }

/* === Header === */
.site-header {
  background: var(--header-bg);
  color: var(--header-text);
  padding: 0.65rem 1.5rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 4px rgba(0,0,0,0.10);
  border-bottom: 3px solid var(--header-border);
}
.site-header h1 { font-size: 1rem; font-weight: 700; letter-spacing: -0.01em; color: var(--header-text); }
.site-header .sub { font-size: 0.78rem; opacity: 0.7; }
.header-logo-wrap {
  background: #fff;
  border-radius: 6px;
  padding: 3px 8px;
  flex-shrink: 0;
  line-height: 0;
}
.header-logo { height: 32px; width: auto; }
.header-divider {
  width: 1px;
  height: 32px;
  background: rgba(128,128,128,0.25);
  flex-shrink: 0;
}

/* === Theme toggle === */
.theme-toggle {
  margin-left: auto;
  background: none;
  border: 1px solid rgba(128,128,128,0.3);
  border-radius: 20px;
  padding: 0.3rem 0.75rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.78rem;
  font-family: var(--font);
  color: var(--header-text);
  transition: all 0.15s;
  white-space: nowrap;
}
.theme-toggle:hover { background: rgba(128,128,128,0.1); border-color: rgba(128,128,128,0.5); }
.theme-toggle svg { width: 14px; height: 14px; flex-shrink: 0; }

/* === Layout === */
.app-layout {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 1.25rem;
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.25rem;
  align-items: start;
}

@media (max-width: 900px) {
  .app-layout { grid-template-columns: 1fr; }
}

/* === Panel === */
.panel {
  background: var(--bg-panel);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  overflow: hidden;
}
.panel-header {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border);
  font-weight: 600;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  user-select: none;
}
.panel-header .chevron {
  margin-left: auto;
  transition: transform 0.2s;
  font-size: 0.75rem;
}
.panel-header.collapsed .chevron { transform: rotate(-90deg); }
.panel-body { padding: 1rem; }
.panel-body.collapsed { display: none; }

/* === Form === */
.form-section { margin-bottom: 1.25rem; }
.form-section:last-child { margin-bottom: 0; }

.field-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}
.field-row.full { grid-template-columns: 1fr; }

.field { display: flex; flex-direction: column; gap: 0.3rem; }
.field label { font-size: 0.8rem; font-weight: 500; color: var(--text-muted); }
.field label .req { color: var(--danger); margin-left: 2px; }

.field input,
.field textarea,
.field select {
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.45rem 0.65rem;
  font-size: 0.9rem;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg-panel);
  transition: border-color 0.15s, box-shadow 0.15s;
  width: 100%;
}
.field input:focus,
.field textarea:focus,
.field select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(58,85,204,0.15);
}
.field input.error,
.field textarea.error { border-color: var(--danger); }

.field textarea { resize: vertical; min-height: 70px; }

.field-error { font-size: 0.75rem; color: var(--danger); }
.char-counter { font-size: 0.72rem; color: var(--text-muted); text-align: right; margin-top: 2px; }

/* === Collapsible address === */
.section-toggle {
  background: none;
  border: none;
  color: var(--accent);
  font-size: 0.8rem;
  cursor: pointer;
  padding: 0;
  font-family: var(--font);
  display: flex;
  align-items: center;
  gap: 0.3rem;
  margin-bottom: 0.5rem;
}
.section-toggle svg { transition: transform 0.2s; }
.section-toggle.open svg { transform: rotate(90deg); }

/* === Style controls === */
.control-group { margin-bottom: 1rem; }
.control-group:last-child { margin-bottom: 0; }
.control-label { font-size: 0.8rem; font-weight: 500; color: var(--text-muted); margin-bottom: 0.5rem; display: block; }

/* Color row */
.color-row { display: flex; align-items: center; gap: 0.5rem; }
.color-swatch {
  width: 36px; height: 36px;
  border-radius: 6px;
  border: 1px solid var(--border);
  cursor: pointer;
  padding: 2px;
  flex-shrink: 0;
}
.color-swatch input[type="color"] { width: 100%; height: 100%; border: none; padding: 0; cursor: pointer; background: none; }
.color-hex {
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.4rem 0.6rem;
  font-size: 0.85rem;
  width: 90px;
  font-family: monospace;
  background: var(--bg-panel);
  color: var(--text);
}

/* Radio pill group */
.pill-group { display: flex; gap: 0.4rem; flex-wrap: wrap; }
.pill-group input[type="radio"] { display: none; }
.pill-group label {
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: all 0.15s;
  display: flex;
  align-items: center;
  gap: 0.3rem;
  background: var(--bg-panel);
}
.pill-group input[type="radio"]:checked + label {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

/* Range slider */
.range-row { display: flex; align-items: center; gap: 0.75rem; }
.range-row input[type="range"] {
  flex: 1;
  accent-color: var(--accent);
  cursor: pointer;
}
.range-value {
  font-size: 0.8rem;
  font-weight: 600;
  min-width: 40px;
  text-align: right;
  color: var(--accent);
}

/* Toggle switch */
.toggle-row { display: flex; align-items: center; gap: 0.65rem; }
.toggle-row label { font-size: 0.85rem; cursor: pointer; }
.toggle {
  position: relative;
  width: 42px;
  height: 24px;
  flex-shrink: 0;
}
.toggle input { opacity: 0; width: 0; height: 0; }
.toggle-track {
  position: absolute;
  inset: 0;
  border-radius: 12px;
  background: var(--border);
  transition: background 0.2s;
  cursor: pointer;
}
.toggle-track::after {
  content: '';
  position: absolute;
  width: 18px; height: 18px;
  border-radius: 50%;
  background: #fff;
  top: 3px; left: 3px;
  transition: transform 0.2s;
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
}
.toggle input:checked ~ .toggle-track { background: var(--accent); }
.toggle input:checked ~ .toggle-track::after { transform: translateX(18px); }

.gradient-fields { display: grid; grid-template-columns: 1fr 1fr; gap: 0.75rem; margin-top: 0.75rem; }
.gradient-fields.hidden { display: none; }

/* === Logo upload === */
.drop-zone {
  border: 2px dashed var(--border);
  border-radius: 8px;
  padding: 1.5rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
  position: relative;
}
.drop-zone:hover,
.drop-zone.drag-over { border-color: var(--gold); background: rgba(201,162,39,0.05); }
.drop-zone input[type="file"] { display: none; }
.drop-zone-icon { font-size: 2rem; margin-bottom: 0.5rem; }
.drop-zone-text { font-size: 0.85rem; color: var(--text-muted); }
.drop-zone-text strong { color: var(--accent); cursor: pointer; }

.logo-preview-wrap { margin-top: 0.75rem; display: none; align-items: center; gap: 0.75rem; }
.logo-preview-wrap.visible { display: flex; }
.logo-thumb { width: 48px; height: 48px; object-fit: contain; border: 1px solid var(--border); border-radius: 6px; }
.logo-name { font-size: 0.8rem; color: var(--text-muted); flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.btn-icon {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.25rem 0.5rem;
  cursor: pointer;
  color: var(--danger);
  font-size: 0.8rem;
  font-family: var(--font);
  transition: all 0.15s;
}
.btn-icon:hover { background: var(--danger); color: #fff; border-color: var(--danger); }

.logo-warning {
  display: none;
  background: #FEF3C7;
  border: 1px solid #F59E0B;
  border-radius: 6px;
  padding: 0.5rem 0.75rem;
  font-size: 0.78rem;
  color: #92400E;
  margin-top: 0.5rem;
}
.logo-warning.visible { display: block; }

/* === Preview Panel === */
.preview-panel { position: sticky; top: 80px; }
.preview-inner { padding: 1rem; }

.qr-preview-wrap {
  position: relative;
  background: var(--bg-panel);
  border-radius: 8px;
  border: 1px solid var(--border);
  overflow: hidden;
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}
.qr-preview-img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  display: block;
}
.qr-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-muted);
  font-size: 0.85rem;
}
.qr-placeholder svg { opacity: 0.3; }

.spinner-overlay {
  position: absolute;
  inset: 0;
  background: color-mix(in srgb, var(--bg-panel) 85%, transparent);
  display: flex;
  align-items: center;
  justify-content: center;
  display: none;
}
.spinner-overlay.active { display: flex; }
.spinner {
  width: 32px; height: 32px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.qr-badge {
  font-size: 0.72rem;
  color: var(--success);
  text-align: center;
  margin-top: 0.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.3rem;
}

.preview-error {
  display: none;
  background: #FEF2F2;
  border: 1px solid #FECACA;
  border-radius: 6px;
  padding: 0.5rem 0.75rem;
  font-size: 0.8rem;
  color: var(--danger);
  margin-top: 0.5rem;
}
.preview-error.visible { display: block; }

/* === Download bar === */
.download-bar {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.5rem;
  margin-top: 0.75rem;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  padding: 0.55rem 0.75rem;
  border-radius: 6px;
  font-size: 0.82rem;
  font-weight: 600;
  font-family: var(--font);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.15s;
  text-decoration: none;
}
.btn:disabled { opacity: 0.45; cursor: not-allowed; }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover:not(:disabled) { background: var(--accent-dark); }
.btn-outline { background: transparent; border-color: var(--border); color: var(--text); }
.btn-outline:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }

.copy-row { display: grid; grid-template-columns: 1fr; margin-top: 0.5rem; }

/* === Generate button === */
.generate-wrap { padding: 1rem; border-top: 1px solid var(--border); }
.btn-generate {
  width: 100%;
  padding: 0.75rem;
  font-size: 1rem;
  border-radius: var(--radius);
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  border: none;
  cursor: pointer;
  transition: background 0.15s;
  font-family: var(--font);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}
.btn-generate:hover { background: var(--accent-dark); }
.btn-generate:disabled { opacity: 0.6; cursor: not-allowed; }

/* === Footer === */
.site-footer {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  padding: 1.25rem 1.5rem;
  margin-top: 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.78rem;
  color: var(--text-muted);
}
.footer-logo { height: 24px; width: auto; opacity: 0.6; }

/* === Utilities === */
.hidden { display: none !important; }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); }
.caption-subfields { margin-top: .65rem; }

@media (max-width: 480px) {
  .field-row { grid-template-columns: 1fr; }
  .download-bar { grid-template-columns: 1fr 1fr; }
}