.a1-course {
  background: linear-gradient(180deg, rgba(7, 21, 37, .96), rgba(9, 26, 43, .96));
}

.a1-shell {
  display: grid;
  grid-template-columns: minmax(230px, .42fr) minmax(0, 1fr);
  gap: 18px;
}

.a1-sidebar,
.a1-panel {
  border: 1px solid rgba(139, 216, 255, .2);
  background: rgba(7, 21, 37, .86);
}

.a1-sidebar {
  padding: 18px;
}

.a1-sidebar h3,
.a1-panel h3 {
  margin: 0 0 12px;
  color: #fff;
  font-size: 24px;
}

.a1-chapters {
  display: grid;
  gap: 8px;
}

.a1-chapter {
  min-height: 52px;
  padding: 12px;
  border: 1px solid rgba(139, 216, 255, .14);
  background: transparent;
  color: #b7cad8;
  text-align: left;
  font: 700 11px 'DM Mono', monospace;
  cursor: pointer;
}

.a1-chapter.active,
.a1-chapter:hover {
  border-color: #ffb45e;
  color: #fff;
  background: rgba(255, 180, 94, .1);
}

.a1-chapter.done::after {
  content: "COMPLETADO";
  display: block;
  margin-top: 6px;
  color: #8bd8ff;
  font-size: 9px;
}

.a1-panel {
  padding: clamp(20px, 4vw, 38px);
}

.a1-topline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 18px;
  color: #8bd8ff;
  font: 700 10px 'DM Mono', monospace;
}

.a1-panel h2 {
  margin: 0 0 12px;
  color: #fff;
  font-size: clamp(30px, 4vw, 54px);
  line-height: 1;
  letter-spacing: -.06em;
}

.a1-objective {
  max-width: 760px;
  color: #b7cad8;
  font-size: 15px;
  line-height: 1.7;
}

.a1-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-top: 22px;
}

.a1-card {
  padding: 16px;
  border: 1px solid rgba(139, 216, 255, .16);
  background: rgba(139, 216, 255, .05);
}

.a1-card h4 {
  margin: 0 0 10px;
  color: #ffb45e;
  font: 700 11px 'DM Mono', monospace;
}

.a1-card p,
.a1-card li {
  color: #c9d8e0;
  font-size: 14px;
  line-height: 1.65;
}

.a1-card ul {
  margin: 0;
  padding-left: 18px;
}

.a1-phrase-list {
  display: grid;
  gap: 10px;
}

.a1-phrase {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: center;
  padding: 12px;
  border-left: 2px solid #8bd8ff;
  background: rgba(139, 216, 255, .06);
}

.a1-phrase strong {
  display: block;
  color: #fff;
  font-size: 18px;
}

.a1-phrase span {
  display: block;
  margin-top: 4px;
  color: #b7cad8;
  font-size: 13px;
}

.a1-audio,
.a1-primary,
.a1-secondary {
  min-height: 44px;
  border: 1px solid rgba(139, 216, 255, .28);
  background: transparent;
  color: #fff;
  font: 700 10px 'DM Mono', monospace;
  cursor: pointer;
}

.a1-audio {
  min-width: 104px;
  color: #8bd8ff;
}

.a1-primary {
  padding: 0 16px;
  border: 0;
  background: #ffb45e;
  color: #071525;
}

.a1-secondary {
  padding: 0 16px;
}

.a1-test {
  display: grid;
  gap: 10px;
}

.a1-option {
  min-height: 44px;
  padding: 10px 12px;
  border: 1px solid rgba(139, 216, 255, .16);
  background: transparent;
  color: #d7e5eb;
  text-align: left;
  cursor: pointer;
}

.a1-option.selected {
  border-color: #ffb45e;
  background: rgba(255, 180, 94, .1);
}

.a1-result {
  min-height: 44px;
  color: #b7cad8;
  font-size: 14px;
  line-height: 1.5;
}

.a1-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
}

@media (max-width: 900px) {
  .a1-shell,
  .a1-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .a1-course {
    padding-inline: 16px;
  }

  .a1-sidebar,
  .a1-panel {
    margin-inline: -4px;
  }

  .a1-phrase {
    grid-template-columns: 1fr;
  }

  .a1-audio,
  .a1-primary,
  .a1-secondary {
    width: 100%;
    font-size: 12px;
  }
}