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

:root {
  --bg: #0b0d17;
  --surface: rgba(255,255,255,0.04);
  --surface2: rgba(255,255,255,0.07);
  --border: rgba(255,255,255,0.08);
  --text: #f1f5f9;
  --muted: #94a3b8;
  --accent: #c084fc;
  --accent2: #60a5fa;
  --sq-light: #f0d9b5;
  --sq-dark: #b58863;
  --sq-light-h: #cdd16f;
  --sq-dark-h: #aaa23a;
  --sq-selected: #f6f669;
  --sq-move: rgba(0,0,0,0.18);
  --sq-capture: rgba(255,0,0,0.22);
  --sq-lastmove-light: #cdd16f;
  --sq-lastmove-dark: #aaa23a;
  --sq-check: rgba(255,30,30,0.75);
  --radius: 16px;
}

html { scroll-behavior: smooth; }
body {
  font-family: 'Outfit', sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  overflow-x: hidden;
  position: relative;
}

/* === Orbs === */
.bg-orbs { position: fixed; inset: 0; pointer-events: none; z-index: 0; }
.orb { position: absolute; border-radius: 50%; filter: blur(100px); opacity: 0.2; animation: float 8s ease-in-out infinite; }
.orb-1 { width: 450px; height: 450px; background: radial-gradient(circle, #7c3aed, transparent); top: -10%; left: -10%; }
.orb-2 { width: 380px; height: 380px; background: radial-gradient(circle, #0ea5e9, transparent); bottom: 0; right: -5%; animation-delay: 3s; }
.orb-3 { width: 300px; height: 300px; background: radial-gradient(circle, #d946ef, transparent); top: 40%; left: 55%; animation-delay: 5s; }
@keyframes float { 0%,100% { transform: translateY(0) scale(1); } 50% { transform: translateY(-25px) scale(1.04); } }

/* === Page Wrapper === */
.page-wrapper {
  position: relative; z-index: 1;
  width: min(980px, 98vw);
  padding: 1.5rem 1rem 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

/* === Header === */
.header {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.nav-link {
  background: var(--surface2);
  border: 1px solid var(--border);
  color: var(--muted);
  text-decoration: none;
  padding: 0.45rem 1rem;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 600;
  transition: all 0.2s;
}
.nav-link:hover { color: var(--text); background: var(--surface2); border-color: var(--accent); }

.title {
  font-size: clamp(1.8rem, 5vw, 2.6rem);
  font-weight: 900;
  letter-spacing: -1px;
}
.title .accent {
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.mode-selector {
  display: flex;
  gap: 0.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 50px;
  padding: 5px;
}
.mode-btn {
  display: flex; align-items: center; gap: 0.4rem;
  padding: 0.45rem 1rem;
  border: none; border-radius: 50px;
  background: transparent; color: var(--muted);
  font-family: 'Outfit', sans-serif; font-size: 0.88rem; font-weight: 600;
  cursor: pointer; transition: all 0.25s;
}
.mode-btn.active {
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: white;
  box-shadow: 0 3px 15px rgba(192,132,252,0.35);
}
.mode-btn:not(.active):hover { background: var(--surface2); color: var(--text); }

/* === Scores Bar === */
.scores-bar {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 50px;
  padding: 0.5rem 1.5rem;
  backdrop-filter: blur(10px);
}
.score-chip { display: flex; align-items: center; gap: 0.5rem; }
.score-icon { font-size: 1.3rem; }
.white-king { filter: drop-shadow(0 0 6px rgba(255,255,255,0.5)); }
.black-king { filter: drop-shadow(0 0 6px rgba(100,100,100,0.8)); }
.score-name { color: var(--muted); font-size: 0.85rem; }
.score-val { font-size: 1.4rem; font-weight: 800; min-width: 1.5rem; text-align: center; }
.score-vs { color: var(--muted); font-size: 0.85rem; font-weight: 600; }

/* === Game Area === */
.game-area {
  display: flex;
  gap: 1rem;
  width: 100%;
  align-items: flex-start;
}

/* === Side Panel === */
.side-panel {
  width: 180px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}
.panel-block {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.85rem;
  backdrop-filter: blur(10px);
}
.panel-block.grow { flex: 1; }
.panel-title {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--muted);
  margin-bottom: 0.7rem;
}

/* Captured */
.captured-group { margin-bottom: 0.6rem; }
.cap-label { font-size: 0.7rem; color: var(--muted); margin-bottom: 0.2rem; }
.cap-pieces { display: flex; flex-wrap: wrap; gap: 1px; min-height: 1.4rem; }
.cap-piece { font-size: 1rem; line-height: 1; }

/* Move History */
.move-list {
  max-height: 280px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 2px;
  scrollbar-width: thin;
  scrollbar-color: rgba(255,255,255,0.1) transparent;
}
.move-row {
  display: grid;
  grid-template-columns: 24px 1fr 1fr;
  gap: 2px;
  padding: 3px 4px;
  border-radius: 6px;
  font-size: 0.78rem;
  font-family: monospace;
}
.move-row.current { background: rgba(192,132,252,0.1); }
.move-num { color: var(--muted); }
.move-w { color: #f1f5f9; }
.move-b { color: #94a3b8; }

/* === Board Area === */
.board-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

/* Status Bar */
.status-bar {
  display: flex; align-items: center; gap: 0.6rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 50px;
  padding: 0.45rem 1.2rem;
  font-size: 0.9rem;
  font-weight: 600;
  backdrop-filter: blur(10px);
  transition: all 0.3s;
  min-width: 220px;
  justify-content: center;
}
.status-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
  transition: background 0.3s;
}
.dot-white { background: #f8fafc; box-shadow: 0 0 8px rgba(255,255,255,0.6); }
.dot-black { background: #334155; box-shadow: 0 0 8px rgba(0,0,0,0.8); }
.dot-check { background: #ef4444; box-shadow: 0 0 10px rgba(239,68,68,0.7); }
.dot-ai    { background: var(--accent); box-shadow: 0 0 10px rgba(192,132,252,0.6); animation: pulse 0.8s ease-in-out infinite; }
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.4} }

/* Board Container */
.board-container {
  display: flex;
  align-items: stretch;
  gap: 4px;
}
.rank-labels {
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  padding: 2px 0;
}
.rank-labels span, .file-labels span {
  font-size: 0.7rem;
  color: var(--muted);
  font-weight: 600;
  width: 14px;
  text-align: center;
  line-height: 1;
}

/* Chess Board */
.chess-board {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  grid-template-rows: repeat(8, 1fr);
  border: 2px solid rgba(255,255,255,0.1);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(0,0,0,0.6), 0 0 0 1px rgba(255,255,255,0.05);
  width: min(480px, calc(100vw - 260px));
  height: min(480px, calc(100vw - 260px));
}

/* File Labels */
.file-labels {
  display: flex;
  justify-content: space-around;
  width: min(480px, calc(100vw - 260px));
  margin-left: 18px;
}

/* === Squares === */
.square {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: filter 0.1s;
  user-select: none;
  aspect-ratio: 1;
}
.sq-light { background: var(--sq-light); }
.sq-dark  { background: var(--sq-dark); }

.square:hover:not(.no-moves) { filter: brightness(1.12); }

/* Highlight states */
.sq-selected { background: var(--sq-selected) !important; }
.sq-lastmove.sq-light { background: var(--sq-lastmove-light); }
.sq-lastmove.sq-dark  { background: var(--sq-lastmove-dark); }
.sq-incheck { background: var(--sq-check) !important; }

/* Move/capture indicators */
.move-dot::after {
  content: '';
  position: absolute;
  width: 32%; height: 32%;
  background: rgba(0,0,0,0.22);
  border-radius: 50%;
  pointer-events: none;
  z-index: 1;
}
.capture-ring::after {
  content: '';
  position: absolute;
  inset: 0;
  border: 4px solid rgba(0,0,0,0.22);
  border-radius: 50%;
  pointer-events: none;
  z-index: 1;
}

/* === Pieces === */
.piece {
  font-size: clamp(1.5rem, 4vw, 2.2rem);
  line-height: 1;
  position: relative;
  z-index: 2;
  cursor: grab;
  transition: transform 0.12s ease;
  user-select: none;
  pointer-events: none;
}
.piece-white { filter: drop-shadow(0 1px 3px rgba(0,0,0,0.5)); }
.piece-black { filter: drop-shadow(0 1px 3px rgba(0,0,0,0.7)); }
.square:hover .piece { transform: scale(1.1); }
.sq-selected .piece { transform: scale(1.15); }

/* Coordinate labels on board */
.coord-rank {
  position: absolute; top: 2px; left: 3px;
  font-size: 0.6rem; font-weight: 700;
  line-height: 1; pointer-events: none; z-index: 3;
}
.coord-file {
  position: absolute; bottom: 2px; right: 3px;
  font-size: 0.6rem; font-weight: 700;
  line-height: 1; pointer-events: none; z-index: 3;
}
.sq-light .coord-rank, .sq-light .coord-file { color: var(--sq-dark); }
.sq-dark  .coord-rank, .sq-dark  .coord-file { color: var(--sq-light); }

/* === Controls === */
.controls {
  display: flex;
  gap: 0.6rem;
  margin-top: 0.25rem;
}
.ctrl-btn {
  flex: 1;
  padding: 0.65rem 1rem;
  border: 1px solid var(--border);
  border-radius: 50px;
  font-family: 'Outfit', sans-serif;
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}
.btn-new {
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: white; border-color: transparent;
  box-shadow: 0 3px 15px rgba(192,132,252,0.3);
}
.btn-new:hover { transform: translateY(-2px); box-shadow: 0 6px 25px rgba(192,132,252,0.4); }
.btn-flip, .btn-undo {
  background: var(--surface2); color: var(--muted);
}
.btn-flip:hover, .btn-undo:hover { color: var(--text); background: rgba(255,255,255,0.08); transform: translateY(-1px); }

/* === Promotion Modal === */
.modal-bg {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(8px);
  display: flex; align-items: center; justify-content: center;
  z-index: 200;
  opacity: 0; pointer-events: none;
  transition: opacity 0.3s;
}
.modal-bg.show { opacity: 1; pointer-events: all; }
.modal-card {
  background: rgba(15,18,30,0.97);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 2rem;
  text-align: center;
  transform: scale(0.8);
  transition: transform 0.3s cubic-bezier(0.34,1.56,0.64,1);
  box-shadow: 0 25px 60px rgba(0,0,0,0.5);
}
.modal-bg.show .modal-card { transform: scale(1); }
.modal-title {
  font-size: 1.1rem; font-weight: 700;
  margin-bottom: 1rem;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.promo-choices { display: flex; gap: 0.75rem; }
.promo-btn {
  width: 64px; height: 64px;
  border: 2px solid var(--border);
  border-radius: 12px;
  background: var(--surface2);
  font-size: 2.2rem;
  cursor: pointer;
  transition: all 0.2s;
  display: flex; align-items: center; justify-content: center;
}
.promo-btn:hover {
  border-color: var(--accent);
  background: rgba(192,132,252,0.15);
  transform: scale(1.1);
}

/* === Game Over Overlay === */
.overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.75);
  backdrop-filter: blur(10px);
  display: flex; align-items: center; justify-content: center;
  z-index: 100;
  opacity: 0; pointer-events: none;
  transition: opacity 0.4s;
}
.overlay.show { opacity: 1; pointer-events: all; }
.result-card {
  background: rgba(15,18,30,0.97);
  border: 1px solid var(--border);
  border-radius: 28px;
  padding: 2.5rem 3rem;
  text-align: center;
  transform: scale(0.6) translateY(40px);
  transition: transform 0.4s cubic-bezier(0.34,1.56,0.64,1);
  box-shadow: 0 30px 80px rgba(0,0,0,0.5);
  min-width: 280px;
}
.overlay.show .result-card { transform: scale(1) translateY(0); }
.result-emoji { font-size: 4rem; margin-bottom: 0.5rem; animation: bounce 0.6s ease 0.3s both; }
@keyframes bounce { 0%{transform:scale(0)} 60%{transform:scale(1.25)} 100%{transform:scale(1)} }
.result-title {
  font-size: 1.9rem; font-weight: 800; margin-bottom: 0.3rem;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.result-sub { color: var(--muted); font-size: 0.95rem; margin-bottom: 1.5rem; }
.btn-play-again {
  width: 100%; padding: 0.9rem;
  border-radius: 50px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color: white; border: none;
  font-family: 'Outfit', sans-serif; font-size: 1rem; font-weight: 700;
  cursor: pointer; transition: all 0.25s;
  box-shadow: 0 4px 20px rgba(192,132,252,0.3);
}
.btn-play-again:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(192,132,252,0.4); }

/* === Responsive === */
@media (max-width: 720px) {
  .game-area { flex-direction: column; align-items: center; }
  .side-panel { width: 100%; flex-direction: row; }
  .panel-block.grow { max-height: 120px; }
  .chess-board { width: min(400px, 95vw); height: min(400px, 95vw); }
  .file-labels { width: min(400px, 95vw); }
  .move-list { max-height: 80px; }
  .header { justify-content: center; }
}
@media (max-width: 480px) {
  .chess-board { width: 92vw; height: 92vw; }
  .file-labels { width: 92vw; }
  .piece { font-size: 1.4rem; }
  .side-panel { display: none; }
}