:root {
  --bg: #ffffff;
  --panel: #f8fafc;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.1);
  --text-main: #1e293b;
  --text-muted: #64748b;
  --danger: #dc2626;
  --square-light: #f1f5f9;
  --square-dark: #94a3b8;
  --border: #e2e8f0;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #ffffff;
  color: var(--text-main);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  padding: 0;
}

.app-shell {
  width: 100%;
  background: #ffffff;
  padding: 1.75rem;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.1fr);
  gap: 1.75rem;
}

@media (max-width: 900px) {
  .app-shell {
    grid-template-columns: minmax(0, 1fr);
  }
}

.header {
  grid-column: 1 / -1;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
  gap: 1rem;
}

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

.brand-link {
  color: inherit;
  text-decoration: none;
}

.brand-link:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.brand-logo {
  width: 56px;
  height: 56px;
  flex-shrink: 0;
}

.brand-text-main {
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  font-size: 1.0rem;
  color: var(--text-main);
}

.brand-text-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.header-pill {
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: #f8fafc;
}

.header-pill-dot {
  width: 7px;
  height: 7px;
  border-radius: 999px;
  background: #4c7059;
  box-shadow: 0 0 0 3px rgba(34, 197, 94, 0.2);
}

.panel {
  background: #f8fafc;
  border-radius: 1.25rem;
  border: 1px solid var(--border);
  padding: 1.25rem 1.4rem;
  position: relative;
  overflow: hidden;
}

.panel::before {
  content: "";
  position: absolute;
  inset: 0;
  background: transparent;
  pointer-events: none;
}

.panel-inner {
  position: relative;
  z-index: 1;
}

.panel-eyebrow {
  font-size: 3rem;
  font-weight: 700;
  color: var(--text-muted);
  opacity: 0.35;
  margin: 0 0 0.25rem;
  letter-spacing: 0.05em;
  line-height: 1;
}

.panel-title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  letter-spacing: 0.03em;
  color: var(--text-main);
}

.panel-subtitle {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1.1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  margin-bottom: 0.9rem;
}

.form-label {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
}

.fen-input {
  width: 100%;
  padding: 0.7rem 0.8rem;
  border-radius: 0.75rem;
  border: 1px solid #cbd5e1;
  background: #ffffff;
  color: var(--text-main);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.fen-input::placeholder {
  color: #94a3b8;
}

.fen-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
  background: #ffffff;
}

.helper-text {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.4;
}

.helper-text code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.75rem;
  background: #f1f5f9;
  padding: 0.15rem 0.35rem;
  border-radius: 0.35rem;
  border: 1px solid var(--border);
  color: var(--text-main);
}

.button-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-top: 0.75rem;
}

.btn-primary {
  border: none;
  border-radius: 999px;
  padding: 0.6rem 1.4rem;
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  color: #ffffff;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
  transition: transform 0.12s ease, box-shadow 0.12s ease, filter 0.12s ease;
}

.btn-primary:hover {
  transform: translateY(-1px);
  filter: brightness(1.05);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.4);
}

.btn-primary:active {
  transform: translateY(0);
  box-shadow: 0 1px 4px rgba(37, 99, 235, 0.3);
}

.btn-primary-icon {
  font-size: 0.9rem;
}

.back-link {
  display: inline-block;
  margin-top: 0.75rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  text-decoration: none;
}

.back-link:hover {
  color: var(--accent);
  text-decoration: underline;
}

.preset-pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.5rem;
}

.preset-pill {
  border-radius: 999px;
  border: 1px solid var(--border);
  padding: 0.25rem 0.6rem;
  font-size: 0.7rem;
  color: var(--text-muted);
  background: #ffffff;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  cursor: pointer;
  transition: border-color 0.12s ease, background 0.12s ease, color 0.12s ease;
}

.preset-pill-dot {
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: #94a3b8;
}

.preset-pill:hover {
  border-color: var(--accent);
  color: var(--text-main);
  background: var(--accent-soft);
}

.board-shell {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.board-meta-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.board-meta-tag {
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: #ffffff;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.board-meta-tag-dot {
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: var(--accent);
}

.board-container {
  aspect-ratio: 1 / 1;
  border-radius: 1rem;
  overflow: hidden;
  border: 1px solid var(--border);
  background: #f1f5f9;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.move-arrows {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 2;
}

.board-placeholder {
  text-align: center;
  padding: 1.25rem;
  max-width: 80%;
  border-radius: 0.9rem;
  background: #ffffff;
  border: 1px dashed #cbd5e1;
  color: var(--text-muted);
  font-size: 0.8rem;
  line-height: 1.5;
}

.board-placeholder-title {
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  color: var(--text-main);
}

.board-placeholder-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
  border: 1px solid rgba(37, 99, 235, 0.3);
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.7rem;
  margin-bottom: 0.4rem;
}

.board-placeholder-badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 999px;
  background: var(--accent);
}

.board-placeholder-sub {
  margin-top: 0.35rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* ---------------------------------------------------------------------------
   Board Grid & Squares
   --------------------------------------------------------------------------- */

.board-grid {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  grid-template-rows: repeat(8, 1fr);
  width: 100%;
  height: 100%;
}

.board-square {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.board-square--light {
  background: var(--square-light);
}

.board-square--dark {
  background: var(--square-dark);
}

.board-square svg {
  width: 85%;
  height: 85%;
}

.board-square--suggested {
  position: relative;
  z-index: 1;
}

.board-square--suggested::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 2px;
  pointer-events: none;
}

.board-square--suggested-1::after {
  background: rgba(34, 197, 94, 0.25);
  box-shadow: inset 0 0 0 2px rgba(34, 197, 94, 0.6);
}

.board-square--suggested-2::after {
  background: rgba(251, 191, 36, 0.25);
  box-shadow: inset 0 0 0 2px rgba(251, 191, 36, 0.6);
}

.board-square--suggested-3::after {
  background: rgba(236, 72, 153, 0.25);
  box-shadow: inset 0 0 0 2px rgba(236, 72, 153, 0.6);
}

/* Rank & file labels */

.board-label {
  position: absolute;
  font-size: 0.6rem;
  font-weight: 600;
  line-height: 1;
  pointer-events: none;
}

.board-label--rank {
  top: 2px;
  left: 3px;
}

.board-square--light .board-label--rank {
  color: var(--square-dark);
}

.board-square--dark .board-label--rank {
  color: var(--square-light);
}

.board-label--file {
  bottom: 2px;
  right: 3px;
}

.board-square--light .board-label--file {
  color: var(--square-dark);
}

.board-square--dark .board-label--file {
  color: var(--square-light);
}

/* ---------------------------------------------------------------------------
   Metadata Pills
   --------------------------------------------------------------------------- */

.board-meta-info {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.meta-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: #ffffff;
  font-size: 0.7rem;
  color: var(--text-muted);
}

.meta-pill-dot {
  width: 8px;
  height: 8px;
  border-radius: 999px;
  flex-shrink: 0;
}

/* ---------------------------------------------------------------------------
   Error Display
   --------------------------------------------------------------------------- */

.board-error {
  text-align: center;
  padding: 1.25rem;
  max-width: 80%;
  border-radius: 0.9rem;
  background: #ffffff;
  border: 1px dashed var(--danger);
  color: var(--text-muted);
  font-size: 0.8rem;
  line-height: 1.5;
}

.board-error-title {
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  color: var(--danger);
}

/* ---------------------------------------------------------------------------
   Suggested Moves
   --------------------------------------------------------------------------- */

.suggested-moves-container {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.opening-name {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.opening-description {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
  line-height: 1.4;
}

.opening-theory-hint {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0.6rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.opening-theory-hint strong {
  color: var(--text-primary);
  font-family: monospace;
}

.suggested-moves-title {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.suggested-move {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.6rem;
  border-radius: 0.5rem;
  border: 1px solid var(--border);
  background: #ffffff;
  font-size: 0.75rem;
  cursor: default;
}

.suggested-move-rank {
  font-weight: 600;
  color: var(--text-main);
  min-width: 1.5rem;
  text-align: center;
}

.suggested-move-notation {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  color: var(--accent);
  font-weight: 600;
  flex-grow: 1;
}

.suggested-move-score {
  color: var(--text-muted);
  font-size: 0.7rem;
}

.suggested-move.gold {
  border-color: #22c55e;
  background: rgba(34, 197, 94, 0.1);
}

.suggested-move.gold .suggested-move-rank {
  color: #22c55e;
}

.suggested-move.silver {
  border-color: #fbbf24;
  background: rgba(251, 191, 36, 0.1);
}

.suggested-move.silver .suggested-move-rank {
  color: #fbbf24;
}

.suggested-move.bronze {
  border-color: #ec4899;
  background: rgba(236, 72, 153, 0.1);
}

.suggested-move.bronze .suggested-move-rank {
  color: #ec4899;
}

.suggested-move-badge {
  font-size: 0.65rem;
  font-weight: 700;
  padding: 0.1rem 0.35rem;
  border-radius: 0.25rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.badge-check {
  background: rgba(251, 191, 36, 0.2);
  color: #b45309;
  border: 1px solid rgba(251, 191, 36, 0.5);
}

.badge-checkmate {
  background: rgba(239, 68, 68, 0.15);
  color: #dc2626;
  border: 1px solid rgba(239, 68, 68, 0.4);
}

.badge-pattern {
  background: rgba(99, 102, 241, 0.12);
  color: #4338ca;
  border: 1px solid rgba(99, 102, 241, 0.35);
}

.suggested-moves-warning {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin: 0.25rem 0 0;
  font-style: italic;
  line-height: 1.4;
}

/* ---------------------------------------------------------------------------
   Site Footer
   --------------------------------------------------------------------------- */

.site-footer {
  grid-column: 1 / -1;
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
  font-size: 0.75rem;
  color: var(--text-muted);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
}

.site-footer a {
  color: var(--text-muted);
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--accent);
  text-decoration: underline;
}

@media (max-width: 560px) {
  .site-footer {
    flex-direction: column;
    align-items: center;
    gap: 0.4rem;
  }
}

/* ---------------------------------------------------------------------------
   Footer
   --------------------------------------------------------------------------- */

.footer-note {
  grid-column: 1 / -1;
  margin-top: 0.5rem;
  font-size: 0.7rem;
  color: var(--text-muted);
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  flex-wrap: wrap;
}

/* ---------------------------------------------------------------------------
   Board Detection Page
   --------------------------------------------------------------------------- */

.app-shell--ingest {
  grid-template-columns: minmax(0, 2fr) minmax(0, 3fr);
}

@media (max-width: 900px) {
  .app-shell--ingest {
    grid-template-columns: minmax(0, 1fr);
  }
}

.app-shell--single-col {
  grid-template-columns: 1fr;
  max-width: 720px;
  margin: 0 auto;
}

#outputCanvas {
  width: 100%;
  max-width: 200px;
  height: auto;
  border-radius: 0.5rem;
  border: 1px solid var(--border);
  display: block;
}

#inputCanvas {
  max-width: 30%;
  height: auto;
  display: block;
  border-radius: 0.5rem;
  border: 1px solid var(--border);
}

#flipLabel {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  cursor: pointer;
}

.flip-reminder {
  font-size: 0.75rem;
  font-weight: 600;
  color: #b45309;
  background: rgba(251, 191, 36, 0.15);
  border: 1px solid rgba(251, 191, 36, 0.4);
  border-radius: 0.375rem;
  padding: 0.3rem 0.6rem;
  margin-bottom: 0.5rem;
}

#squares {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 2px;
  max-width: 480px;
}

#squares canvas {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 2px;
  cursor: pointer;
  box-sizing: border-box;
  border: 2px solid transparent;
}

#squares canvas.overridden {
  border-color: #3b82f6;
}

.piece-picker {
  position: fixed;
  z-index: 10;
  background: #1e293b;
  border-radius: 0.5rem;
  padding: 0.35rem;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.piece-picker-row {
  display: flex;
  gap: 0.2rem;
}

.piece-picker button {
  width: 2rem;
  height: 2rem;
  border: 1px solid #334155;
  border-radius: 0.25rem;
  font-size: 0.85rem;
  font-weight: 700;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.1s, border-color 0.1s;
}

.piece-picker button:hover {
  border-color: #3b82f6;
}

.piece-picker button.piece-white {
  background: #f1f5f9;
  color: #1e293b;
}

.piece-picker button.piece-white:hover {
  background: #dbeafe;
}

.piece-picker button.piece-black {
  background: #334155;
  color: #e2e8f0;
}

.piece-picker button.piece-black:hover {
  background: #475569;
}

.piece-picker button.piece-empty {
  background: #475569;
  color: #94a3b8;
  flex: 1;
  width: auto;
  font-weight: 500;
  font-family: system-ui, sans-serif;
  font-size: 0.7rem;
}

.piece-picker button.piece-empty:hover {
  background: #64748b;
}

.piece-picker-preview {
  display: flex;
  justify-content: center;
  padding-bottom: 0.3rem;
  border-bottom: 1px solid #334155;
  margin-bottom: 0.1rem;
}

.piece-picker-preview canvas {
  border-radius: 0.2rem;
  display: block;
  image-rendering: pixelated;
}

.panel h3 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin: 1rem 0 0.5rem;
}

.footer-note strong {
  font-weight: 600;
  color: var(--text-main);
}

.footer-note code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.7rem;
  background: #f1f5f9;
  padding: 0.1rem 0.3rem;
  border-radius: 0.3rem;
  border: 1px solid var(--border);
  color: var(--text-main);
}

/* ---------------------------------------------------------------------------
   Processing Indicator
   --------------------------------------------------------------------------- */

.processing-indicator {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.75rem;
}

.processing-spinner {
  width: 14px;
  height: 14px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  flex-shrink: 0;
  animation: spin 0.7s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ── Landing page ─────────────────────────────────────────── */
.landing-nav-panel {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.landing-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
}

@media (max-width: 600px) {
  .landing-nav {
    grid-template-columns: 1fr;
  }
}

.landing-nav-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.5rem;
  padding: 1.5rem 1.75rem;
  border: 1px solid var(--border);
  border-radius: 1rem;
  background: var(--panel);
  text-decoration: none;
  color: var(--text-main);
  transition: border-color 0.15s ease, box-shadow 0.15s ease, transform 0.15s ease;
}

.landing-nav-card:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.12);
  transform: translateY(-2px);
}

.landing-nav-icon {
  font-size: 2rem;
  line-height: 1;
}

.landing-nav-label {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
}

.landing-nav-desc {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.45;
}

/* Product recommendations page */
.product-blog {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.product-entry {
  display: grid;
  grid-template-columns: 88px minmax(0, 1fr);
  gap: 0.9rem;
  padding: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  background: #ffffff;
}

.product-entry-image {
  width: 88px;
  height: 128px;
  object-fit: cover;
  border-radius: 0.45rem;
  border: 1px solid var(--border);
}

.product-entry-content h2 {
  font-size: 0.95rem;
  margin-bottom: 0.2rem;
}

.product-entry-content h2 a {
  color: var(--text-main);
  text-decoration: none;
}

.product-entry-content h2 a:hover {
  color: var(--accent);
  text-decoration: underline;
}

.product-entry-byline {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
}

.product-entry-byline a {
  color: inherit;
}

.product-entry-content p {
  font-size: 0.83rem;
  line-height: 1.5;
  color: var(--text-main);
}

@media (max-width: 560px) {
  .product-entry {
    grid-template-columns: 1fr;
  }

  .product-entry-image {
    width: 72px;
    height: 104px;
  }
}