:root {
  --bg: #0b1020;
  --panel: rgba(18, 24, 42, 0.88);
  --panel-strong: rgba(26, 32, 58, 0.96);
  --line: rgba(255, 255, 255, 0.08);
  --text: #f4f7ff;
  --muted: #a7b0dc;
  --accent: #6ee7ff;
  --accent-2: #b59bff;
  --good: #59f0b4;
  --danger: #ff7898;
  --shadow: 0 18px 48px rgba(0, 0, 0, 0.38);
  --radius: 24px;
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  color: var(--text);
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background:
    radial-gradient(circle at top, #2a335f 0%, #11162a 42%, #070a13 100%);
  overflow-x: hidden;
  overflow-y: auto;
}

button {
  font: inherit;
}

.app {
  min-height: 100dvh;
  padding: 24px;
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  gap: 18px;
  grid-template-rows: auto minmax(0, 1fr);
}

.topbar,
.board-panel,
.panel,
.overlay-card {
  background: var(--panel);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.topbar {
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: end;
}

.eyebrow {
  margin: 0 0 6px;
  color: var(--accent);
  font-size: 0.86rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.topbar h1 {
  margin: 0 0 8px;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
}

.topbar p {
  margin: 0;
  color: var(--muted);
}

.hud {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: flex-end;
  align-items: center;
}

.stat {
  min-width: 130px;
  padding: 12px 14px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
  text-align: center;
}

.stat span {
  display: block;
  color: var(--muted);
  font-size: 0.8rem;
  margin-bottom: 4px;
}

.stat strong {
  font-size: 1.18rem;
}

.btn {
  border: 0;
  border-radius: 16px;
  padding: 12px 18px;
  cursor: pointer;
  font-weight: 800;
  color: #08101f;
  background: linear-gradient(135deg, #8ce9ff 0%, #bca7ff 100%);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.22);
}

.btn:hover {
  filter: brightness(1.04);
}

.btn.primary {
  min-width: 128px;
}

.game-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 260px;
  gap: 18px;
  align-items: start;
}

.board-panel {
  min-height: 0;
  border-radius: var(--radius);
  padding: 18px;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.panel-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  margin-bottom: 16px;
}

.panel-head h2,
.panel h2 {
  margin: 0 0 6px;
  font-size: 1.05rem;
}

.panel-head p,
.status-panel p {
  margin: 0;
  color: var(--muted);
}

.record-badge {
  padding: 10px 14px;
  border-radius: 999px;
  background: linear-gradient(135deg, rgba(89, 240, 180, 0.22), rgba(110, 231, 255, 0.18));
  color: #cffff1;
  border: 1px solid rgba(89, 240, 180, 0.35);
  font-weight: 800;
  letter-spacing: 0.06em;
}

.hidden {
  display: none !important;
}

.board {
  width: 100%;
  margin: auto;
  display: grid;
  grid-template-columns: repeat(13, minmax(0, 1fr));
  gap: 10px;
}

.card {
  position: relative;
  border: 0;
  padding: 0;
  cursor: pointer;
  background: transparent;
  aspect-ratio: 2 / 3;
}

.card:disabled {
  cursor: default;
}

.card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  display: block;
}

/* ไม่ใช้ 3D flip อีกต่อไป */

.card-face {
  position: absolute;
  inset: 0;
  border-radius: 20px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.04);
}

/* หน้าหลัง (ตอนคว่ำ: แสดง | ตอนเปิด: หายทันที) */
.card-back {
  background:
    radial-gradient(circle at 25% 20%, rgba(255, 255, 255, 0.18), transparent 22%),
    radial-gradient(circle at 70% 80%, rgba(255, 255, 255, 0.14), transparent 26%),
    linear-gradient(145deg, #1b2f63 0%, #101935 48%, #091021 100%);
  display: grid;
  place-items: center;
  transform: scaleX(1);
  opacity: 1;
  z-index: 2;
  /* คว่ำกลับ: หลังไพ่แสดงหลังจากด้านหน้าหาย (มี delay) */
  transition: transform 0.18s ease-in 0.18s, opacity 0.18s ease-in 0.18s;
}

.back-pattern {
  position: absolute;
  inset: 5px;
  border-radius: 10px;
  border: 1px dashed rgba(255, 255, 255, 0.16);
  opacity: 0.85;
}

.back-mark {
  position: relative;
  font-size: clamp(1.2rem, 2.8vw, 2rem);
  color: rgba(255, 255, 255, 0.9);
  text-shadow: 0 4px 12px rgba(0, 0, 0, 0.35);
}

/* หน้าไพ่ (ตอนคว่ำ: ซ่อน | ตอนเปิด: แสดงหลังจากหลังหาย) */
.card-front {
  background: linear-gradient(145deg, #ffffff 0%, #edf2ff 100%);
  color: #111827;
  display: grid;
  place-items: center;
  padding: 5px;
  transform: scaleX(0);
  opacity: 0;
  z-index: 1;
  /* คว่ำกลับ: หน้าไพ่ซ่อนทันที (ไม่มี delay) */
  transition: transform 0.18s ease-in 0s, opacity 0.18s ease-in 0s;
}

/* เปิดไพ่: หลังหายทันที, หน้าแสดงหลังจากหลังหาย */
.card.face-up .card-back,
.card.matched .card-back {
  transform: scaleX(0);
  opacity: 0;
  z-index: 1;
  transition: transform 0.18s ease-in 0s, opacity 0.18s ease-in 0s;
}

.card.face-up .card-front,
.card.matched .card-front {
  transform: scaleX(1);
  opacity: 1;
  z-index: 2;
  transition: transform 0.18s ease-out 0.18s, opacity 0.18s ease-out 0.18s;
}

/* glow effect ตอนเลือก */
.card.active .card-back,
.card.active .card-front {
  box-shadow: 0 0 0 2px rgba(110, 231, 255, 0.6),
              inset 0 0 0 1px rgba(255, 255, 255, 0.1);
}

.card-front::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at top left, rgba(255, 255, 255, 0.3), transparent 50%);
  opacity: 0.6;
  pointer-events: none;
}

.card-corner,
.card-center {
  position: relative;
  z-index: 1;
}

.card-corner {
  position: absolute;
  display: flex;
  flex-direction: column;
  line-height: 0.9;
  gap: 2px;
  font-weight: 800;
  color: var(--card-color);
}

.card-corner.top {
  top: 4px;
  left: 5px;
}

.card-corner.bottom {
  right: 5px;
  bottom: 4px;
  transform: rotate(180deg);
  align-items: end;
}

.card-corner .rank {
  font-size: clamp(0.55rem, 1.1vw, 0.9rem);
}

.card-corner .suit {
  font-size: clamp(0.5rem, 1vw, 0.85rem);
}

.card-center {
  display: grid;
  place-items: center;
  gap: 1px;
  font-weight: 900;
  color: var(--card-color);
  text-shadow: 0 4px 10px rgba(0, 0, 0, 0.08);
  max-width: 100%;
  overflow: hidden;
  text-align: center;
}

.center-rank {
  font-size: clamp(1rem, 2.8vw, 2rem);
  line-height: 1;
}

.center-suit {
  font-size: clamp(0.9rem, 2.4vw, 1.8rem);
  line-height: 1;
}

.card.matched {
  cursor: default;
}

.card.matched .card-face {
  border-color: rgba(89, 240, 180, 0.65);
  box-shadow: 0 0 0 1px rgba(89, 240, 180, 0.18), inset 0 0 0 1px rgba(255, 255, 255, 0.05);
}

.card.matched .card-front {
  filter: saturate(1.05) brightness(1.02);
}

.sidebar {
  display: grid;
  gap: 16px;
}

.panel {
  border-radius: var(--radius);
  padding: 18px;
}

.panel ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  display: grid;
  gap: 8px;
}

.status-panel {
  min-height: 110px;
  display: grid;
  align-content: start;
}

.overlay {
  position: fixed;
  inset: 0;
  background: rgba(5, 8, 16, 0.72);
  backdrop-filter: blur(8px);
  display: grid;
  place-items: center;
  padding: 20px;
}

.overlay-card {
  width: min(420px, 100%);
  border-radius: 28px;
  padding: 28px;
  text-align: center;
}

.overlay-label {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 0.85rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.overlay-card h2 {
  margin: 0 0 10px;
  font-size: 2rem;
}

.overlay-card p {
  margin: 8px 0;
  color: var(--muted);
}

.overlay-card .record-badge {
  margin: 16px auto 18px;
  display: inline-flex;
}

@media (max-width: 960px) {
  .game-shell {
    grid-template-columns: 1fr;
  }

  .sidebar {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .board {
    grid-template-columns: repeat(7, minmax(0, 1fr));
  }
}

@media (max-width: 680px) {
  .app {
    padding: 14px;
    gap: 12px;
  }

  .topbar {
    flex-direction: column;
    align-items: start;
  }

  .hud {
    justify-content: start;
  }

  .board {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 5px;
  }

  .sidebar {
    display: none;
  }

  .panel-head {
    flex-direction: column;
    align-items: start;
  }
}