/* ===== Bộ nhận diện: bảng đen + phấn + vở ô ly + mực tím ===== */
:root {
  --board: #1F3B33;        /* bảng đen (xanh) */
  --board-2: #29493F;
  --chalk: #F3F1E7;        /* phấn trắng */
  --chalk-dim: rgba(243,241,231,.68);
  --chalk-yellow: #FFD54A; /* phấn vàng — nút Bắt đầu */
  --wood: #8A5A2E;         /* khung bảng gỗ */
  --wood-d: #6B4321;
  --paper: #FDFCF8;        /* giấy vở */
  --grid: #C9BEEA;         /* dòng kẻ ô ly đậm */
  --grid-soft: #ECE7F8;    /* dòng kẻ ô ly mảnh */
  --ink: #4B2E9E;          /* mực tím */
  --ink-soft: #7A7392;
  --red: #D2343B;          /* mực đỏ của giáo viên */
  --text: #1F2A28;
  --hand: "Patrick Hand", "Be Vietnam Pro", cursive;
  /* bí danh để code cũ vẫn chạy */
  --green: var(--board); --muted: var(--ink-soft); --line: #DDD6EE;
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; overflow: hidden; background: #8ec5ff; font-family: "Be Vietnam Pro", system-ui, sans-serif; color: var(--text); }
canvas { display: block; width: 100vw; height: 100vh; }
button { font-family: inherit; }
:focus-visible { outline: 3px solid var(--chalk-yellow); outline-offset: 2px; }

/* Mặt bảng đen: nền xanh + vệt phấn mờ + viền gỗ */
.board {
  background:
    radial-gradient(120% 80% at 20% 10%, rgba(255,255,255,.06), transparent 60%),
    radial-gradient(90% 70% at 85% 90%, rgba(255,255,255,.04), transparent 60%),
    var(--board);
  border: 5px solid var(--wood);
  box-shadow: inset 0 0 0 1px rgba(0,0,0,.25), inset 0 2px 12px rgba(0,0,0,.35), 0 8px 24px rgba(10,20,15,.35);
  color: var(--chalk);
}

/* Phím tắt viết bằng phấn */
kbd {
  font-family: inherit; font-size: 11px; font-weight: 700; padding: 1px 7px; border-radius: 5px;
  border: 1.5px solid currentColor; opacity: .85; background: transparent;
}

/* Nút chung */
.btn {
  font-size: 15px; font-weight: 600; border-radius: 10px; cursor: pointer; padding: 9px 16px;
  display: inline-flex; align-items: center; gap: 8px; border: 1.5px solid transparent; white-space: nowrap;
  transition: transform .12s, background-color .15s;
}
.btn:active { transform: translateY(1px); }

/* ----- Thanh chọn trò (khay bảng đen phía trên) ----- */
.modes {
  position: fixed; top: 12px; left: 16px; z-index: 5; display: flex; gap: 2px; padding: 4px;
  border-radius: 12px; border-width: 4px;
  max-width: calc(100vw - 32px); overflow-x: auto; scrollbar-width: none; /* nhiều trò: cuộn ngang khi chật */
}
.modes a {
  text-decoration: none; display: inline-flex; align-items: center;
  font-size: 14px; font-weight: 600; border: 0; background: transparent; color: var(--chalk-dim);
  padding: 7px 12px; border-radius: 8px; cursor: pointer; white-space: nowrap;
}
.modes a:hover { color: var(--chalk); background: rgba(255,255,255,.06); }
.modes a.on { background: var(--chalk); color: var(--board); box-shadow: 0 2px 0 rgba(0,0,0,.25); }
.modes.locked { opacity: .55; pointer-events: none; }

/* ----- Thanh điều khiển dưới cùng ----- */
.bar {
  position: fixed; left: 50%; bottom: 14px; transform: translateX(-50%); z-index: 4;
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap; justify-content: center;
  padding: 10px 12px 10px 18px; border-radius: 14px; max-width: calc(100vw - 24px);
  transition: opacity .3s, transform .3s;
}
.bar.hidden { opacity: 0; pointer-events: none; transform: translateX(-50%) translateY(24px); }
.bar .hint { font-size: 14px; color: var(--chalk-dim); margin-right: 4px; }
.bar .hint b { color: var(--chalk); font-weight: 700; }
.bar .btn { background: rgba(255,255,255,.07); color: var(--chalk); border-color: rgba(243,241,231,.35); }
.bar .btn:hover { background: rgba(255,255,255,.14); }
.bar .btn.primary, .btn.go {
  background: var(--chalk-yellow); color: var(--board); border-color: var(--chalk-yellow);
  font-size: 17px; font-weight: 800; padding: 10px 20px; box-shadow: 0 3px 0 #C9A12A;
}
.bar .btn.primary:hover, .btn.go:hover { background: #FFDF6E; }
.bar .btn.primary:active, .btn.go:active { box-shadow: 0 1px 0 #C9A12A; transform: translateY(2px); }
#muteBtn { padding: 9px 12px; }
#settingsBtn.armed::after { content: ''; width: 7px; height: 7px; border-radius: 50%; background: var(--chalk-yellow); }

/* ----- Lớp phủ + trang vở ----- */
.overlay {
  position: fixed; inset: 0; display: grid; place-items: center; padding: 16px; z-index: 10;
  background: rgba(14,28,24,.5); backdrop-filter: blur(2px);
  opacity: 0; pointer-events: none; transition: opacity .3s;
}
.overlay.show { opacity: 1; pointer-events: auto; }
.card {
  --margin: 56px;                          /* vị trí đường lề đỏ */
  position: relative; width: min(600px, 100%);
  padding: 26px 28px 22px calc(var(--margin) + 18px);
  border-radius: 4px 4px 6px 6px; color: var(--text);
  background-color: var(--paper);
  background-image:
    linear-gradient(90deg, transparent calc(var(--margin) - 1px), #E7A3A3 calc(var(--margin) - 1px), #E7A3A3 calc(var(--margin) + 1px), transparent calc(var(--margin) + 1px)),
    repeating-linear-gradient(0deg, var(--grid) 0 1px, transparent 1px 32px),
    repeating-linear-gradient(0deg, var(--grid-soft) 0 1px, transparent 1px 8px),
    repeating-linear-gradient(90deg, var(--grid-soft) 0 1px, transparent 1px 32px);
  box-shadow: 0 1px 0 #E6E1D3, 0 2px 0 #F7F5EE, 0 3px 0 #E6E1D3, 0 24px 60px rgba(0,0,0,.4);
  transform: translateY(14px) rotate(-.6deg); transition: transform .45s cubic-bezier(.2,1.2,.4,1);
}
.card :focus-visible { outline-color: var(--ink); }
.overlay.show .card { transform: rotate(-.6deg); }
.card .head { display: flex; gap: 12px; align-items: center; padding-right: 150px; }
.card .head > div { padding-right: 0; }
.card h2 { margin: 0; font-size: 27px; font-weight: 800; line-height: 1.2; color: var(--board); }
.card .cap { order: 2; margin-top: 2px; font-size: 14px; font-weight: 500; color: var(--ink); letter-spacing: 0; text-transform: none; }
.card .head > div { display: flex; flex-direction: column; }
.card .head > div h2 { order: 1; }
#resDuckIcon, #resUfoIcon { flex: none; }

/* con dấu đỏ của giáo viên — đóng sau khi tên đã được viết xong */
.stamp {
  position: absolute; right: 24px; top: 22px; color: var(--red); border: 4px double var(--red);
  border-radius: 6px; padding: 3px 12px; font-weight: 800; font-size: 17px; letter-spacing: .02em;
  transform: rotate(-11deg) scale(1.8); opacity: 0; mix-blend-mode: multiply;
}
.overlay.show .stamp { animation: stamp .35s 1.25s cubic-bezier(.3,1.6,.5,1) forwards; }
@keyframes stamp { to { opacity: .88; transform: rotate(-11deg) scale(1); } }

/* danh sách tên viết tay bằng mực tím */
.rows { list-style: none; margin: 18px 0 8px; padding: 0; display: grid; gap: 6px; }
.row { display: flex; align-items: center; gap: 14px; min-height: 64px; }
.row .no {
  flex: none; width: 34px; height: 34px; border: 2px solid var(--ink); border-radius: 50%;
  display: grid; place-items: center; font-family: var(--hand); font-size: 22px; color: var(--ink); line-height: 1;
}
.row svg { flex: none; border-radius: 50%; background: rgba(201,190,234,.35); }
.row .n {
  font-family: var(--hand); font-size: clamp(30px, 5.4vw, 42px); line-height: 1.05; color: var(--ink);
  clip-path: inset(0 100% 0 0);
}
.overlay.show .row .n { animation: write .7s cubic-bezier(.5,0,.3,1) forwards; animation-delay: var(--d, .15s); }
@keyframes write { to { clip-path: inset(0 0 0 0); } }
.row .k { font-size: 13px; color: var(--ink-soft); margin-top: 2px; }
.meta { font-size: 14px; color: var(--ink-soft); margin: 6px 0 18px; }
.actions { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.card .btn { background: transparent; color: var(--board); border-color: var(--board); }
.card .btn:hover { background: rgba(31,59,51,.06); }
.card .btn.primary { background: var(--board); color: var(--chalk); border-color: var(--board); box-shadow: 0 3px 0 #10221C; }
.card .btn.primary:hover { background: var(--board-2); }
.card .btn.primary:active { box-shadow: 0 1px 0 #10221C; transform: translateY(2px); }
.card .btn.quiet { border-color: transparent; color: var(--red); padding-left: 6px; padding-right: 6px; }

/* ----- Cài đặt: trang vở kẻ ngang, gọn hơn ----- */
.modal .card {
  width: min(560px, 100%); max-height: calc(100vh - 32px); overflow: auto; transform: none;
  background-image:
    linear-gradient(90deg, transparent calc(var(--margin) - 1px), #E7A3A3 calc(var(--margin) - 1px), #E7A3A3 calc(var(--margin) + 1px), transparent calc(var(--margin) + 1px));
}
.overlay.show.modal .card { transform: none; }
.modal h2 { margin-bottom: 4px; }
.modal .cap { font-size: 14px; color: var(--ink); }
.field { display: grid; gap: 6px; margin-top: 16px; font-size: 14px; font-weight: 700; color: var(--board); }
.field input[type=text], .field input[type=number], .field textarea {
  font-family: inherit; font-size: 15px; font-weight: 400; padding: 9px 12px; width: 100%; color: var(--text);
  background: #fff; border: 1.5px solid #D5CDEA; border-radius: 8px;
}
.field input:focus, .field textarea:focus { outline: none; border-color: var(--ink); box-shadow: 0 0 0 3px rgba(75,46,158,.15); }
.field textarea { min-height: 170px; resize: vertical; line-height: 1.55; }
.field small { font-weight: 400; color: var(--ink-soft); font-size: 13px; }
.check { display: flex; gap: 10px; align-items: flex-start; margin-top: 14px; font-size: 14px; line-height: 1.45; }
.check input { width: 18px; height: 18px; margin-top: 1px; accent-color: var(--ink); flex: none; }
.seg { display: flex; gap: 3px; padding: 4px; border-radius: 10px; width: fit-content; background: var(--board); }
.seg button { font-size: 14px; font-weight: 600; border: 0; background: transparent; color: var(--chalk-dim); padding: 7px 14px; border-radius: 7px; cursor: pointer; }
.seg button:hover { color: var(--chalk); }
.seg button.on { background: var(--chalk); color: var(--board); }
.chips { display: flex; flex-wrap: wrap; gap: 6px; max-height: 190px; overflow: auto; padding: 2px; }
.chip { font-size: 14px; border: 1.5px solid #D5CDEA; background: #fff; color: var(--text); padding: 5px 11px; border-radius: 999px; cursor: pointer; display: inline-flex; gap: 6px; align-items: center; }
.chip:hover { border-color: var(--ink); }
.chip.on { background: var(--ink); border-color: var(--ink); color: #fff; font-weight: 600; }
.chip .no { background: #fff; color: var(--ink); border-radius: 999px; padding: 0 6px; font-size: 12px; font-weight: 800; }
.meta.warn { color: var(--red); font-weight: 600; }
.two { display: grid; grid-template-columns: 1fr 130px; gap: 12px; }

@media (max-width: 560px) {
  .card { --margin: 30px; padding: 20px 16px 18px calc(var(--margin) + 12px); }
  .card .head { padding-right: 0; }
  .card h2 { font-size: 22px; }
  .stamp { top: -16px; right: 12px; background: var(--paper); font-size: 14px; }
  .two { grid-template-columns: 1fr; }
  .bar { padding: 8px; gap: 8px; flex-wrap: nowrap; } .bar .hint { display: none; }
  .btn kbd { display: none; }   /* điện thoại không có phím Space */
  .modes { left: 50%; transform: translateX(-50%); top: 8px; max-width: calc(100vw - 16px); overflow-x: auto; scrollbar-width: none; }
  .modes a { font-size: 13px; padding: 6px 9px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .01ms !important; animation-delay: 0s !important; transition-duration: .01ms !important; }
}

/* ===== Trang menu chọn trò (index.html) ===== */
.menu-page { overflow: auto; background:
  radial-gradient(120% 90% at 50% 0%, #2b5246 0%, #1a3029 60%, #12221d 100%); }
.menu { max-width: 980px; margin: 0 auto; padding: 32px 16px 48px; }
.menu-board { border-radius: 16px; padding: 28px 24px 24px; text-align: center; margin-bottom: 28px; }
.menu-board h1 {
  margin: 0; font-family: var(--hand); font-weight: 400; font-size: clamp(44px, 8vw, 76px); line-height: 1;
  color: var(--chalk); text-shadow: 0 0 1px rgba(255,255,255,.6), 2px 2px 0 rgba(0,0,0,.25); letter-spacing: .01em;
}
.menu-board p { margin: 10px 0 0; color: var(--chalk-dim); font-size: 17px; }
.game-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 16px; }
.game-card {
  position: relative; display: grid; gap: 4px; justify-items: start; text-decoration: none; color: var(--text);
  padding: 18px 18px 18px calc(18px + 14px); border-radius: 6px;
  background-color: var(--paper);
  background-image:
    linear-gradient(90deg, transparent 13px, #E7A3A3 13px, #E7A3A3 15px, transparent 15px),
    repeating-linear-gradient(0deg, var(--grid-soft) 0 1px, transparent 1px 8px);
  box-shadow: 0 2px 0 #d9d3c3, 0 14px 30px rgba(0,0,0,.35);
  transition: transform .15s, box-shadow .15s;
}
.game-card:nth-child(odd) { transform: rotate(-.6deg); }
.game-card:nth-child(even) { transform: rotate(.5deg); }
.game-card:hover { transform: translateY(-4px) rotate(0); box-shadow: 0 2px 0 #d9d3c3, 0 20px 40px rgba(0,0,0,.45); }
.game-card:focus-visible { outline: 3px solid var(--chalk-yellow); outline-offset: 3px; }
.gc-icon { font-size: 40px; line-height: 1.1; }
.gc-name { font-family: var(--hand); font-size: 30px; color: var(--ink); line-height: 1.1; }
.gc-desc { font-size: 14px; color: var(--ink-soft); }
.game-card.last { box-shadow: 0 0 0 3px var(--chalk-yellow), 0 14px 30px rgba(0,0,0,.35); }
.gc-tag {
  position: absolute; top: 10px; right: 10px; font-size: 11px; font-weight: 700; color: var(--board);
  background: var(--chalk-yellow); padding: 2px 8px; border-radius: 999px;
}
.menu-foot { text-align: center; color: var(--chalk-dim); font-size: 14px; margin-top: 26px; }
@media (prefers-reduced-motion: reduce) { .game-card, .game-card:hover { transform: none; } }