@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:wght@400;600&family=DM+Sans:wght@400;500&display=swap');

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

:root {
  --light-sq: #F0D9B5;
  --dark-sq: #B58863;
  --board-border: #7a5c38;
  --board-shadow: #4a3018;
  --selected: #BBCC44;
  --last-move-l: #CDD26A;
  --last-move-d: #AABA42;
  --hint-blue: rgba(68,170,255,0.8);
  --panel-bg: #faf7f2;
  --panel-border: #ddd5c5;
  --text: #2c1f0e;
  --text-muted: #7a6a55;
  --btn-bg: #f0e8da;
  --btn-hover: #e0d0b8;
  --btn-primary: #7a5c38;
  --btn-primary-hover: #5a3e20;
  --commentary-bg: #fffdf9;
  --commentary-border: #e8dcc8;
}

@media (prefers-color-scheme: dark) {
  :root {
    --panel-bg: #1a1610;
    --panel-border: #3a3020;
    --text: #f0e8da;
    --text-muted: #a09070;
    --btn-bg: #2e2618;
    --btn-hover: #3e3628;
    --btn-primary: #c8904a;
    --btn-primary-hover: #a87030;
    --commentary-bg: #1e1a12;
    --commentary-border: #3a3020;
  }
}

body {
  font-family: 'DM Sans', sans-serif;
  background: var(--panel-bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 16px;
}

#app {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  width: 100%;
  max-width: 480px;
}

/* ── Header ── */
#header { text-align: center; }

h1 {
  font-family: 'Playfair Display', serif;
  font-size: 24px;
  font-weight: 600;
  color: var(--text);
}

#subtitle {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 2px;
}

/* ── Difficulty bar ── */
#difficulty-bar {
  display: flex;
  gap: 6px;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
}

#difficulty-bar label {
  font-size: 12px;
  color: var(--text-muted);
  font-weight: 500;
}

.diff-btn {
  font-family: 'DM Sans', sans-serif;
  font-size: 12px;
  font-weight: 500;
  padding: 5px 12px;
  border-radius: 20px;
  border: 1px solid var(--panel-border);
  background: var(--btn-bg);
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.15s;
}

.diff-btn:hover { background: var(--btn-hover); color: var(--text); }

.diff-btn.active {
  background: var(--btn-primary);
  color: #fff;
  border-color: var(--btn-primary);
}

/* ── Status ── */
#status-bar {
  font-size: 13px;
  color: var(--text-muted);
  text-align: center;
  font-weight: 500;
  min-height: 18px;
}

/* ── Board ── */
#board-wrap { position: relative; width: 100%; }

#board-container {
  border: 8px solid var(--board-border);
  border-radius: 4px;
  box-shadow: 0 6px 24px rgba(0,0,0,0.3), inset 0 0 0 1px rgba(255,255,255,0.08);
  overflow: hidden;
  width: 100%;
  aspect-ratio: 1;
  position: relative;
}

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

.sq {
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  position: relative;
  font-size: clamp(20px, 5.5vw, 38px);
  user-select: none;
  transition: filter 0.1s;
  -webkit-tap-highlight-color: transparent;
}

.sq.light { background: var(--light-sq); }
.sq.dark  { background: var(--dark-sq); }
.sq.selected  { background: var(--selected) !important; }
.sq.last-move-l { background: var(--last-move-l) !important; }
.sq.last-move-d { background: var(--last-move-d) !important; }
.sq:hover { filter: brightness(1.08); }

.sq.legal-move::after {
  content: '';
  position: absolute;
  width: 32%; height: 32%;
  border-radius: 50%;
  background: rgba(0,0,0,0.18);
  pointer-events: none;
}

.sq.legal-capture::after {
  content: '';
  position: absolute;
  inset: 4%;
  border-radius: 50%;
  border: 5px solid rgba(0,0,0,0.18);
  pointer-events: none;
}

.sq.hint-from { background: rgba(68,170,255,0.35) !important; }
.sq.hint-to   { background: rgba(68,170,255,0.55) !important; }

.coord-label {
  position: absolute;
  font-size: 9px;
  font-weight: 700;
  opacity: 0.75;
  pointer-events: none;
  line-height: 1;
}
.coord-file { bottom: 2px; right: 3px; }
.coord-rank { top: 2px; left: 3px; }
.on-light { color: var(--dark-sq); }
.on-dark  { color: var(--light-sq); }

/* ── Result overlay ── */
#result-overlay {
  display: none;
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.62);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  z-index: 20;
  backdrop-filter: blur(3px);
}
#result-overlay.show { display: flex; }

#result-text {
  font-family: 'Playfair Display', serif;
  font-size: 26px;
  font-weight: 600;
  color: #fff;
  text-align: center;
  text-shadow: 0 2px 12px rgba(0,0,0,0.9);
  white-space: pre-line;
}

#result-btns { display: flex; gap: 10px; }

.btn-overlay {
  padding: 9px 22px;
  border-radius: 8px;
  border: none;
  font-family: 'DM Sans', sans-serif;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-overlay.primary { background: #F0D9B5; color: #3a2a10; }
.btn-overlay.primary:hover { background: #ddc89a; }
.btn-overlay.secondary { background: rgba(255,255,255,0.15); color: #fff; border: 1px solid rgba(255,255,255,0.3); }
.btn-overlay.secondary:hover { background: rgba(255,255,255,0.25); }

/* ── Controls ── */
#controls {
  display: flex;
  gap: 7px;
  flex-wrap: wrap;
  justify-content: center;
}

button.ctrl {
  font-family: 'DM Sans', sans-serif;
  font-size: 12px;
  font-weight: 500;
  padding: 7px 14px;
  border-radius: 8px;
  border: 1px solid var(--panel-border);
  background: var(--btn-bg);
  color: var(--text);
  cursor: pointer;
  transition: background 0.15s, opacity 0.15s;
  flex: 1;
  min-width: 70px;
}
button.ctrl:hover { background: var(--btn-hover); }
button.ctrl:disabled { opacity: 0.38; cursor: default; }
button.ctrl.primary { background: var(--btn-primary); color: #fff; border-color: var(--btn-primary); }
button.ctrl.primary:hover { background: var(--btn-primary-hover); }

/* ── Commentary panel ── */
#commentary-wrap {
  border: 1px solid var(--commentary-border);
  border-radius: 10px;
  background: var(--commentary-bg);
  padding: 10px 14px;
  min-height: 54px;
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

#commentary-icon {
  font-size: 18px;
  flex-shrink: 0;
  margin-top: 1px;
}

#commentary-text {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text);
  flex: 1;
}

#commentary-text.muted { color: var(--text-muted); font-style: italic; }

.loading-dots::after {
  content: '';
  animation: dots 1.2s steps(4, end) infinite;
}
@keyframes dots {
  0%,100% { content: ''; }
  25%  { content: '.'; }
  50%  { content: '..'; }
  75%  { content: '...'; }
}

/* ── Move log ── */
#move-log-wrap {
  border: 1px solid var(--panel-border);
  border-radius: 10px;
  padding: 8px 12px;
  background: var(--panel-bg);
  max-height: 100px;
  overflow-y: auto;
  scrollbar-width: thin;
}

#move-log {
  font-size: 12px;
  line-height: 1.9;
  font-variant-numeric: tabular-nums;
}

.move-num { color: var(--text-muted); }
.move-w   { color: var(--text); }
.move-b   { color: var(--text-muted); }

/* ── Analysis panel ── */
#analysis-wrap {
  display: none;
  border: 1px solid var(--commentary-border);
  border-radius: 10px;
  background: var(--commentary-bg);
  padding: 14px 16px;
}

#analysis-wrap.show { display: block; }

#analysis-title {
  font-family: 'Playfair Display', serif;
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text);
}

#analysis-text {
  font-size: 13px;
  line-height: 1.7;
  color: var(--text);
  white-space: pre-line;
}

#analysis-text strong { font-weight: 500; color: var(--btn-primary); }

/* ── Stockfish loading indicator ── */
#sf-status {
  font-size: 11px;
  color: var(--text-muted);
  text-align: center;
}