:root {
  --bg: #000;
  --fg: rgba(255,255,255,0.92);
  --muted: rgba(255,255,255,0.66);
  --neon: #00e5ff;
  --neon2: #b300ff;
  --stroke: rgba(255,255,255,0.10);
  --card: rgba(255,255,255,0.06);
  --card2: rgba(255,255,255,0.035);
  --nh-radius: 14px;
}

*, *::before, *::after { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  line-height: 1.55;
  overflow-x: hidden;
  min-height: 100vh;
}

a { color: inherit; text-decoration: none; }

/* ── Ambient background (shared with main site) ───────────────── */
.ambient {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
}
.glow {
  position: absolute;
  width: 520px;
  height: 520px;
  border-radius: 999px;
  filter: blur(60px);
  opacity: 0.25;
}
.glow--a {
  top: -140px;
  left: -120px;
  background: radial-gradient(circle at 30% 30%, var(--neon), transparent 60%);
}
.glow--b {
  bottom: -160px;
  right: -120px;
  background: radial-gradient(circle at 50% 50%, var(--neon2), transparent 60%);
}
.grid {
  position: absolute;
  inset: 0;
  opacity: 0.12;
  background-image:
    linear-gradient(to right, rgba(255,255,255,0.06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255,255,255,0.06) 1px, transparent 1px);
  background-size: 80px 80px;
  mask-image: radial-gradient(circle at 50% 20%, rgba(0,0,0,1), rgba(0,0,0,0) 70%);
}

/* ── Header (shared with main site) ────────────────────────────── */
.header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(10px);
  background: rgba(0,0,0,0.60);
  border-bottom: 1px solid var(--stroke);
  z-index: 50;
}
.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1100px, calc(100% - 40px));
  margin: 0 auto;
  padding: 14px 0;
  gap: 16px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: Orbitron, Inter, system-ui, sans-serif;
  letter-spacing: 0.08em;
}
.brand__mark {
  color: var(--neon);
  text-shadow: 0 0 14px rgba(0,229,255,0.35);
}
.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
}
.nav__link {
  padding: 8px 10px;
  border: 1px solid transparent;
  border-radius: 999px;
  color: var(--muted);
  font-size: 14px;
  transition: border-color 200ms ease, color 200ms ease, background 200ms ease;
}
.nav__link:hover {
  color: var(--fg);
  border-color: rgba(255,255,255,0.14);
  background: rgba(255,255,255,0.04);
}
.nav__link--accent {
  color: var(--neon);
  border-color: rgba(0,229,255,0.25);
  background: rgba(0,229,255,0.06);
}
.nav__link--accent:hover {
  color: #fff;
  border-color: rgba(0,229,255,0.45);
  background: rgba(0,229,255,0.12);
}

/* ── Main layout ───────────────────────────────────────────────── */
.nh-main {
  width: min(1000px, calc(100% - 40px));
  margin: 0 auto;
  padding: 0.5rem 0 4rem;
}

/* ── App state visibility ──────────────────────────────────────── */
.app-state        { display: none; }
.app-state.active { display: block; }

/* Upload */
.upload-container {
  max-width: 520px;
  margin: 1rem auto 0;
  text-align: center;
}

.nh-logo {
  font-family: Orbitron, Inter, system-ui, sans-serif;
  font-size: 2rem;
  font-weight: 700;
  color: var(--neon);
  text-shadow: 0 0 18px rgba(0,229,255,0.35);
  letter-spacing: 0.04em;
  margin: 0;
}

.nh-tagline {
  color: var(--muted);
  margin: 0.5rem 0 2rem;
  font-size: 0.95rem;
}

.nh-credits {
  margin-top: 1.25rem;
  font-size: 0.8rem;
  color: var(--muted);
  text-align: center;
}

/* Dropzone */
.dropzone {
  border: 2px dashed var(--stroke);
  border-radius: var(--nh-radius);
  padding: 2.5rem 1.5rem;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
}
.dropzone:hover,
.dropzone.drag-over {
  border-color: var(--neon);
  background: rgba(0,229,255,0.04);
}

.dropzone-icon {
  width: 40px;
  height: 40px;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

.dropzone-content p { margin: 0.25rem 0; }
.dropzone-hint      { font-size: 0.8rem; color: var(--muted); }

.file-label {
  color: var(--neon);
  cursor: pointer;
  text-decoration: underline;
}

.file-name {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: var(--neon);
  min-height: 1.2em;
}

/* Settings */
.settings-panel {
  margin-top: 1.5rem;
  background: var(--card);
  border: 1px solid var(--stroke);
  border-radius: var(--nh-radius);
  padding: 1.25rem 1.5rem;
  text-align: left;
}

.settings-panel h3 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--muted);
  margin: 0 0 1rem;
  font-family: Orbitron, Inter, system-ui, sans-serif;
}

.settings-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.setting { flex: 1 1 45%; }

.setting label {
  display: block;
  font-size: 0.8rem;
  color: var(--muted);
  margin-bottom: 0.3rem;
}

.setting input[type="number"] {
  width: 100%;
  background: rgba(0,0,0,0.6);
  border: 1px solid var(--stroke);
  border-radius: 10px;
  color: var(--fg);
  padding: 0.45rem 0.6rem;
  font-size: 0.9rem;
  outline: none;
}
.setting input[type="number"]:focus {
  border-color: rgba(0,229,255,0.40);
  box-shadow: 0 0 0 3px rgba(0,229,255,0.10);
}

.setting-full { flex: 1 1 100%; }

.setting input[type="password"] {
  width: 100%;
  background: rgba(0,0,0,0.6);
  border: 1px solid var(--stroke);
  border-radius: 10px;
  color: var(--fg);
  padding: 0.45rem 0.6rem;
  font-size: 0.9rem;
  font-family: monospace;
  outline: none;
}
.setting input[type="password"]:focus {
  border-color: rgba(0,229,255,0.40);
  box-shadow: 0 0 0 3px rgba(0,229,255,0.10);
}

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

.setting-toggle { flex: 1 1 100%; }

.toggle-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.toggle-hint {
  font-size: 0.75rem;
  color: var(--muted);
  margin-top: 0.25rem;
}

/* Buttons */
.btn {
  font-family: inherit;
  font-size: 0.9rem;
  border: 1px solid rgba(255,255,255,0.14);
  border-radius: var(--nh-radius);
  padding: 0.6rem 1.4rem;
  cursor: pointer;
  transition: transform 180ms ease, background 200ms ease, border-color 200ms ease;
  background: rgba(255,255,255,0.04);
  color: var(--fg);
}
.btn:hover { transform: translateY(-1px); }
.btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
}

.btn--primary {
  border-color: rgba(0,229,255,0.40);
  background: rgba(0,229,255,0.10);
  box-shadow: 0 0 0 1px rgba(0,229,255,0.12) inset;
  color: var(--neon);
  font-weight: 600;
}
.btn--primary:hover:not(:disabled) {
  background: rgba(0,229,255,0.18);
  border-color: rgba(0,229,255,0.55);
}

.btn--ghost {
  background: transparent;
}

.nh-btn {
  margin-top: 1.5rem;
  width: 100%;
  padding: 0.75rem;
  font-size: 1rem;
}

.nh-btn-sm {
  padding: 0.4rem 1rem;
  font-size: 0.85rem;
}

/* Analyzing */
.analyzing-container {
  max-width: 480px;
  margin: 4rem auto 0;
  text-align: center;
}

.analyzing-container h2 {
  font-size: 1.25rem;
  font-family: Orbitron, Inter, system-ui, sans-serif;
  color: var(--fg);
  margin: 0 0 1.5rem;
}

.progress-wrapper { margin-bottom: 1.5rem; }

.nh-progress-bar {
  width: 100%;
  height: 8px;
  background: rgba(255,255,255,0.08);
  border-radius: 4px;
  overflow: hidden;
}

.nh-progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--neon), var(--neon2));
  border-radius: 4px;
  transition: width 0.3s ease;
  box-shadow: 0 0 12px rgba(0,229,255,0.3);
}

.progress-text {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: var(--muted);
}

.found-moves {
  text-align: left;
  margin-bottom: 1.5rem;
  max-height: 200px;
  overflow-y: auto;
}

.found-move-item {
  padding: 0.5rem 0.75rem;
  margin-bottom: 0.35rem;
  background: var(--card);
  border-radius: 10px;
  font-size: 0.82rem;
  color: var(--fg);
  border-left: 3px solid var(--neon);
}

/* Viewer */

/* Nav bars */
.nav-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.6rem 0;
}

.nav-label {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--fg);
  min-width: 120px;
  text-align: center;
}

.keyboard-hint {
  font-size: 0.75rem;
  color: var(--muted);
}

/* Main viewer layout */
.viewer-main {
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
}

.board-col {
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  width: 444px;
}

.board-wrapper {
  border: 2px solid var(--stroke);
  border-radius: 10px;
  overflow: hidden;
  line-height: 0;
  box-shadow: 0 0 30px rgba(0,229,255,0.08);
}

/* chessboard2 sizing */
#board { width: 440px; height: 440px; }

/* Sidebar */
.sidebar {
  flex: 1;
  background: var(--card);
  border: 1px solid var(--stroke);
  border-radius: var(--nh-radius);
  padding: 0.9rem 1.25rem;
  min-width: 220px;
}

.info-field {
  margin-bottom: 0.5rem;
}

.info-row {
  display: flex;
  gap: 1.5rem;
}

.info-row .info-field {
  flex: 1;
}

.nav-indicator {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0;
}


.info-label {
  display: block;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--neon);
  font-weight: 600;
  font-family: Orbitron, Inter, system-ui, sans-serif;
  margin-bottom: 0.15rem;
}

.move-notation {
  font-family: Inter, system-ui, sans-serif;
  text-transform: none;
}

.info-value {
  display: block;
  font-size: 0.95rem;
  color: var(--fg);
  word-break: break-word;
}

.highlight-value {
  font-weight: 700;
  font-size: 1.05rem;
}

.accent-value {
  color: var(--neon);
  font-weight: 700;
  font-size: 1.1rem;
  text-shadow: 0 0 10px rgba(0,229,255,0.25);
}

.sidebar-divider {
  border: none;
  border-top: 1px solid var(--stroke);
  margin: 0.5rem 0;
}

.tooltip-anchor {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 1px solid var(--neon);
  color: var(--neon);
  font-size: 0.6rem;
  font-family: Inter, system-ui, sans-serif;
  font-weight: 700;
  text-transform: none;
  letter-spacing: 0;
  cursor: default;
  vertical-align: middle;
  margin-left: 0.3rem;
  opacity: 0.7;
  transition: opacity 0.15s;
}

.tooltip-anchor:hover {
  opacity: 1;
}

.tooltip-anchor::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 7px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--panel, #1a1a2e);
  border: 1px solid var(--stroke);
  color: var(--fg);
  font-size: 0.73rem;
  font-family: Inter, system-ui, sans-serif;
  font-weight: 400;
  text-transform: none;
  letter-spacing: 0;
  line-height: 1.5;
  padding: 0.5rem 0.7rem;
  border-radius: 6px;
  white-space: pre-line;
  width: max-content;
  max-width: 280px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s;
  z-index: 100;
  box-shadow: 0 4px 16px rgba(0,0,0,0.4);
}

.tooltip-anchor:hover::after {
  opacity: 1;
}

/* Bottom bar */
.bottom-bar {
  border-top: 1px solid var(--stroke);
  margin-top: 0.25rem;
  padding-top: 0.75rem;
}

/* Viewer actions */
.viewer-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 1rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--stroke);
}

/* Responsive */
@media (max-width: 700px) {
  .nh-main { padding: 1rem 0; width: calc(100% - 20px); }

  .viewer-main {
    flex-direction: column;
  }

  #board { width: 100%; height: auto; aspect-ratio: 1; }

  .board-wrapper { width: 100%; }

  .sidebar { min-width: unset; }

  .keyboard-hint { display: none; }

  .nav-bar { flex-wrap: wrap; justify-content: center; }

  .header__inner { padding: 10px 0; }
  .nav { gap: 6px; }
}

/* "New!" badge */
.badge-new {
  display: inline-block;
  font-family: Inter, system-ui, sans-serif;
  font-size: 0.6rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: #000;
  background: var(--neon);
  padding: 0.15em 0.45em;
  border-radius: 4px;
  vertical-align: middle;
  margin-left: 0.3em;
  box-shadow: 0 0 8px rgba(0,229,255,0.4);
  animation: badge-pulse 2s ease-in-out infinite;
}

@keyframes badge-pulse {
  0%, 100% { box-shadow: 0 0 8px rgba(0,229,255,0.4); }
  50% { box-shadow: 0 0 16px rgba(0,229,255,0.7); }
}