/* keyboard — bàn phím ảo + màu tay + feedback. */
.keyboard {
  display: flex;
  flex-direction: column;
  gap: 8px;
  background: var(--c-surface);
  padding: 16px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  max-width: 100%;
  overflow-x: auto;
  position: relative;
}

/* Gợi ý giữ Shift khi cần ký hiệu / chữ hoa */
.keyboard__shift-hint {
  position: absolute;
  top: -14px;
  right: 16px;
  background: var(--c-primary);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: 999px;
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.15s ease, transform 0.15s ease;
  pointer-events: none;
}
.keyboard--shift .keyboard__shift-hint {
  opacity: 1;
  transform: translateY(0);
}
.keyboard-row {
  display: flex;
  gap: 8px;
  justify-content: center;
}
.key {
  min-width: 40px;
  height: 46px;
  border-radius: 10px;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 1.05rem;
  background: #eef2fb;
  color: var(--c-ink);
  border: 2px solid transparent;
  transition: transform 0.1s ease, background 0.12s ease, border-color 0.12s ease;
  user-select: none;
}
.key--space { min-width: 260px; }

/* Màu nền nhạt theo tay để phân biệt trái/phải */
.key.hand--left  { background: #eef1ff; }
.key.hand--right { background: #eafaf1; }

.key__label { pointer-events: none; }

/* Trạng thái */
.key--target {
  border-color: var(--c-target);
  background: var(--c-target);
  color: var(--c-ink);
  transform: translateY(-3px);
  box-shadow: 0 6px 14px rgba(255,209,102,0.6);
  animation: keyPulse 1s ease-in-out infinite;
}
.key--correct {
  background: var(--c-correct) !important;
  color: #fff;
  border-color: var(--c-correct);
}
.key--wrong {
  background: var(--c-wrong) !important;
  color: #fff;
  border-color: var(--c-wrong);
}

@keyframes keyPulse {
  0%, 100% { box-shadow: 0 6px 14px rgba(255,209,102,0.6); }
  50%      { box-shadow: 0 6px 22px rgba(255,209,102,0.95); }
}

body.a11y-reduce .key--target { animation: none; }