/* Atividade: cartões para aprender, perguntas, vídeo do sinal e a faixa de baixo.
   (A ordem dos arquivos no index.html importa: veja o comentário lá.) */

/* ===================================================================
   ATIVIDADE (inspirada no Duolingo)
   Tela cheia: em cima, sair + barra de progresso + vidas; no meio, o cartão
   do sinal (aprender) ou a pergunta; embaixo, uma faixa fixa com o botão.
   Depois de conferir, a faixa fica turquesa (acertou) ou coral (errou).
   =================================================================== */
.lesson {
  width: min(760px, 100%);
  min-height: calc(100vh / var(--zoom) - 20px); /* com zoom, 100vh "vale" mais: divide de volta */
  display: flex;
  flex-direction: column;
  margin: 0 auto;
  padding-bottom: 100px; /* espaço para a faixa fixa de baixo (o JS ajusta depois de conferir) */
}

.lesson-top { display: flex; align-items: center; gap: 16px; }
.lesson-close {
  width: 44px;
  height: 44px;
  flex: none;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 12px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 22px;
}
.lesson-close:hover { background: var(--surface-soft); color: var(--text); }
.lesson-progress { flex: 1; height: 16px; overflow: hidden; border-radius: 99px; background: var(--surface-soft); }
.lesson-progress span {
  height: 100%;
  display: block;
  border-radius: inherit;
  background: var(--accent);
  box-shadow: inset 0 -4px 0 rgba(0, 0, 0, 0.1);
  transition: width 320ms cubic-bezier(0.2, 0.8, 0.2, 1);
}
.lesson-lives { display: inline-flex; align-items: center; gap: 6px; color: var(--coral); font-family: "Manrope", sans-serif; font-size: 18px; font-weight: 800; }
.lesson-lives.is-losing .bi { animation: heart-shake 500ms ease-in-out; }
@keyframes heart-shake {
  0%, 100% { transform: rotate(0) scale(1); }
  25% { transform: rotate(-14deg) scale(1.2); }
  75% { transform: rotate(14deg) scale(1.2); }
}
.lesson-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: 99px;
  background: var(--primary-soft);
  color: var(--primary);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.lesson-body { flex: 1; display: flex; flex-direction: column; justify-content: center; gap: 16px; padding: 20px 0 16px; }
.lesson-kicker { margin: 0; color: var(--muted); font-size: 12px; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; }
.lesson-body h2 { margin: 0; font-family: "Manrope", sans-serif; font-size: 26px; font-weight: 800; line-height: 1.25; }
/* Etiqueta da pergunta que voltou no fim (segunda chance) */
.lesson-retry { align-self: flex-start; display: inline-flex; align-items: center; gap: 6px; margin-bottom: -6px; padding: 5px 12px; border-radius: 99px; background: var(--yellow-soft); color: #9a7408; font-size: 12px; font-weight: 800; letter-spacing: 0.06em; text-transform: uppercase; }
:root[data-theme="dark"] .lesson-retry { color: var(--yellow); }

/* Vídeo do sinal (ou o espaço reservado, enquanto não foi gravado) */
.sign-video {
  width: min(440px, 100%, (100vh / var(--zoom) - 400px) * 1.6); /* em telas baixas, encolhe para caber */
  aspect-ratio: 16 / 10;
  margin: 0 auto;
  border-radius: 20px;
  background: #0f1b2b;
  object-fit: cover;
}
.sign-video.is-placeholder {
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 6px;
  border: 2px dashed var(--line);
  background: var(--surface-soft);
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}
.sign-video-play { color: var(--primary); font-size: 46px; }
.sign-preview { padding: 2px 10px; border-radius: 99px; background: var(--surface); font-size: 12px; font-weight: 700; }
.sign-video-small { width: 100%; border-radius: 12px; }
.sign-video-small.is-placeholder { gap: 4px; font-size: 11px; }
.sign-video-small.is-placeholder > span { display: none; } /* cartão pequeno: só o play e a prévia */
.sign-video-small .sign-preview { padding: 1px 8px; font-size: 11px; white-space: nowrap; }
.sign-video-small .sign-video-play { font-size: 30px; }

/* Aprender: nome do sinal e dica */
.learn-word { margin: 0; font-family: "Manrope", sans-serif; font-size: 34px; font-weight: 800; text-align: center; }
.learn-tip { max-width: 480px; margin: -8px auto 0; color: var(--muted); font-size: 16px; line-height: 1.5; text-align: center; }

/* Respostas: botões "3D" que afundam ao apertar */
.answer-list { display: grid; gap: 12px; }
.answer-option {
  width: 100%;
  min-height: 60px;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 12px 16px;
  border: 2px solid var(--line);
  border-radius: 16px;
  background: var(--surface);
  box-shadow: 0 4px 0 var(--line);
  color: var(--text);
  cursor: pointer;
  font: inherit;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
  text-align: left;
  transition: transform 80ms ease, box-shadow 80ms ease;
}
.answer-option:hover:not(:disabled) { background: var(--surface-soft); }
.answer-option:active:not(:disabled) { transform: translateY(4px); box-shadow: 0 0 0 transparent; }
.answer-option:disabled { cursor: default; }
.answer-option.is-selected { border-color: var(--primary); background: var(--primary-soft); box-shadow: 0 4px 0 var(--primary); }
.answer-option.is-correct { border-color: var(--accent); background: var(--accent-soft); box-shadow: 0 4px 0 var(--accent); }
.answer-option.is-incorrect { border-color: var(--coral); background: var(--coral-soft); box-shadow: 0 4px 0 var(--coral); }
.answer-key {
  width: 28px;
  height: 28px;
  flex: none;
  display: grid;
  place-items: center;
  border: 2px solid var(--line);
  border-radius: 8px;
  color: var(--muted);
  font-family: "Manrope", sans-serif;
  font-size: 13px;
  font-weight: 800;
}
.answer-option.is-selected .answer-key { border-color: var(--primary); color: var(--primary); }
.answer-option.is-correct .answer-key { border-color: var(--accent); color: var(--accent); }
.answer-option.is-incorrect .answer-key { border-color: var(--coral); color: var(--coral); }

/* Vídeo → palavra: no computador, vídeo à esquerda e respostas à direita */
.question-split { display: grid; gap: 16px; }
@media (min-width: 900px) {
  .question-split { grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); align-items: center; gap: 24px; }
  .question-split .sign-video { width: 100%; }
}

/* Palavra → vídeo: cartões de vídeo lado a lado */
.answer-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; }
.answer-grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.answer-video { flex-direction: column; gap: 8px; padding: 8px 8px 10px; }

/* Verdadeiro ou falso: a frase e dois botões grandes */
.tf-statement {
  margin: 0;
  padding: 24px;
  border: 2px solid var(--line);
  border-radius: 20px;
  background: var(--surface);
  font-family: "Manrope", sans-serif;
  font-size: 20px;
  font-weight: 700;
  line-height: 1.4;
  text-align: center;
}
.answer-tf { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
.answer-tf .answer-option { min-height: 112px; flex-direction: column; justify-content: center; gap: 6px; font-size: 18px; font-weight: 800; text-align: center; }
.answer-tf .answer-option > .bi { font-size: 32px; }
.answer-true > .bi { color: var(--accent); }
.answer-false > .bi { color: var(--coral); }

/* Faixa fixa de baixo: dica ou resultado + botão */
.lesson-footer {
  position: fixed;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 10;
  padding: 18px 16px calc(18px + env(safe-area-inset-bottom));
  border-top: 2px solid var(--line);
  background: var(--bg);
  transition: background-color 160ms ease;
}
.lesson-footer-inner { width: min(760px, 100%); display: flex; align-items: center; justify-content: space-between; gap: 16px; margin: 0 auto; }
.lesson-feedback { min-width: 0; display: flex; align-items: center; gap: 12px; color: var(--muted); font-size: 14px; }
.lesson-feedback strong { display: block; font-family: "Manrope", sans-serif; font-size: 18px; font-weight: 800; }
.lesson-feedback small { display: block; margin-top: 2px; color: var(--text); font-size: 14px; line-height: 1.45; }
.feedback-icon { width: 46px; height: 46px; flex: none; display: grid; place-items: center; border-radius: 50%; background: var(--surface); font-size: 22px; }
.lesson-next { min-width: 190px; flex: none; }
.lesson-footer.is-correct { border-top-color: transparent; background: var(--accent-soft); }
.lesson-footer.is-correct .lesson-feedback strong,
.lesson-footer.is-correct .feedback-icon { color: var(--accent); }
.lesson-footer.is-correct .lesson-next { background: var(--accent); box-shadow: 0 4px 0 var(--done-shadow); }
.lesson-footer.is-incorrect { border-top-color: transparent; background: var(--coral-soft); }
.lesson-footer.is-incorrect .lesson-feedback strong,
.lesson-footer.is-incorrect .feedback-icon { color: var(--coral); }
.lesson-footer.is-incorrect .lesson-next { background: var(--coral); box-shadow: 0 4px 0 #b84a3a; }
/* no escuro o turquesa e o coral são claros: texto escuro no botão para ler bem */
:root[data-theme="dark"] .lesson-footer.is-correct .lesson-next,
:root[data-theme="dark"] .lesson-footer.is-incorrect .lesson-next { color: #10202b; }

@media (prefers-reduced-motion: reduce) {
  .lesson-lives.is-losing .bi { animation: none; }
}

@media (max-width: 1000px) {
  .lesson { min-height: 0; padding-bottom: 124px; }
  .lesson-top { gap: 10px; }
  .lesson-body { justify-content: flex-start; gap: 14px; padding: 18px 0; }
  .lesson-body h2 { font-size: 22px; }
  .sign-video { width: min(100%, (100dvh / var(--zoom) - 420px) * 1.6); }
  .question-split .sign-video { width: min(100%, (100dvh / var(--zoom) - 535px) * 1.6); } /* vídeo + 3 respostas: o vídeo encolhe para tudo caber */
  .learn-word { font-size: 28px; }
  .learn-tip { font-size: 15px; }
  .answer-option { min-height: 54px; padding: 10px 14px; font-size: 15px; }
  .answer-grid { gap: 8px; }
  .answer-grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .answer-tf .answer-option { min-height: 96px; }
  .tf-statement { padding: 18px; font-size: 18px; }
  .lesson-footer { padding: 14px 16px calc(14px + env(safe-area-inset-bottom)); }
  .lesson-footer-inner { flex-direction: column; align-items: stretch; gap: 12px; }
  .lesson-next { width: 100%; min-width: 0; }
  .feedback-icon { width: 38px; height: 38px; font-size: 18px; }
  .lesson-feedback strong { font-size: 16px; }
  .lesson-feedback small { font-size: 13px; }
}