* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: #fff;
  color: #1a1a1a;
  min-height: 100dvh;
}

#app {
  max-width: 600px;
  margin: 0 auto;
  padding: 20px 16px;
  min-height: 100dvh;
  display: flex;
  align-items: flex-start;
}

#loading {
  width: 100%;
  text-align: center;
  padding: 40px 0;
  color: #888;
  font-size: 16px;
}

#quiz {
  width: 100%;
}

.hidden { display: none; }

#exam-label {
  font-size: 13px;
  color: #1a3a5c;
  letter-spacing: 0.02em;
  margin-bottom: 20px;
  opacity: 0.8;
}

#question-text {
  font-size: 18px;
  line-height: 1.5;
  margin-bottom: 24px;
  font-weight: 500;
}

#options {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.option-btn {
  width: 100%;
  min-height: 52px;
  padding: 14px 16px;
  font-size: 16px;
  line-height: 1.4;
  text-align: left;
  border: 1.5px solid #d0d0d0;
  border-radius: 10px;
  background: #fff;
  color: #1a1a1a;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s, opacity 0.2s;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

.option-btn:active:not(.disabled) {
  background: #f0f4f8;
}

.option-btn .letter {
  font-weight: 600;
  margin-right: 8px;
  color: #1a3a5c;
}

.option-btn.correct {
  background: #e6f4ea;
  border-color: #34a853;
  color: #1a6b30;
}

.option-btn.incorrect {
  background: #fce8e6;
  border-color: #ea4335;
  color: #a50e0e;
}

.option-btn.disabled {
  pointer-events: none;
  opacity: 0.55;
}

.option-btn.correct.disabled,
.option-btn.incorrect.disabled {
  opacity: 1;
}

#feedback {
  margin-top: 20px;
  font-size: 16px;
  line-height: 1.4;
  min-height: 24px;
}

#feedback.correct-msg { color: #1a6b30; }
#feedback.incorrect-msg { color: #a50e0e; }
#feedback.anulada-msg { color: #666; }

.fade-enter {
  opacity: 0;
  transform: translateY(12px);
}

.fade-active {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.25s ease, transform 0.25s ease;
}