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

body {
  background: #0a0a1a;
  color: #e8e8ff;
  font-family: 'Segoe UI', sans-serif;
  min-height: 100vh;
  background-image: radial-gradient(ellipse at top, #0d0d2b 0%, #0a0a1a 70%);
}

#app {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 16px;
}

header {
  text-align: center;
  margin-bottom: 28px;
}

h1 {
  font-size: 2rem;
  font-weight: 700;
  color: #a78bfa;
  margin-bottom: 6px;
}

.subtitle {
  font-size: 1rem;
  color: #8888aa;
  margin-bottom: 16px;
}

#scoreboard {
  display: flex;
  justify-content: center;
  gap: 32px;
  font-size: 0.95rem;
  color: #aaaacc;
}

#scoreboard strong {
  color: #e8e8ff;
}

#image-container {
  position: relative;
  width: 100%;
  aspect-ratio: 16/9;
  background: #111130;
  border-radius: 12px;
  overflow: hidden;
  margin-bottom: 24px;
  border: 1px solid #2a2a4a;
}

#nasa-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: none;
}

#loader {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #6666aa;
  font-size: 0.95rem;
}

#question-box {
  text-align: center;
}

#question-text {
  font-size: 1.1rem;
  margin-bottom: 18px;
  color: #ccccee;
}

#choices {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.choice-btn {
  background: #12122a;
  border: 1px solid #2a2a5a;
  color: #ddddf8;
  padding: 14px 10px;
  border-radius: 10px;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
}

.choice-btn:hover {
  background: #1a1a40;
  border-color: #5555aa;
  transform: translateY(-1px);
}

.choice-btn.correct {
  background: #0f3d2a;
  border-color: #2ecc71;
  color: #2ecc71;
}

.choice-btn.wrong {
  background: #3d0f0f;
  border-color: #e74c3c;
  color: #e74c3c;
}

.choice-btn:disabled {
  cursor: default;
  transform: none;
}

#feedback {
  margin-top: 24px;
  background: #12122a;
  border: 1px solid #2a2a4a;
  border-radius: 12px;
  padding: 20px;
  text-align: center;
}

#feedback-text {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 10px;
}

#nasa-explanation {
  font-size: 0.88rem;
  color: #9999bb;
  line-height: 1.6;
  margin-bottom: 18px;
  max-height: 80px;
  overflow: hidden;
}

#next-btn, #restart-btn {
  background: #a78bfa;
  color: #0a0a1a;
  border: none;
  padding: 12px 28px;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
}

#next-btn:hover, #restart-btn:hover {
  background: #c4b5fd;
  transform: translateY(-1px);
}

#end-screen {
  text-align: center;
  margin-top: 40px;
  padding: 40px 20px;
  background: #12122a;
  border-radius: 16px;
  border: 1px solid #2a2a4a;
}

#end-screen h2 {
  font-size: 1.8rem;
  color: #a78bfa;
  margin-bottom: 16px;
}

#end-screen p {
  font-size: 1.1rem;
  margin-bottom: 10px;
  color: #ccccee;
}

#end-comment {
  color: #8888aa;
  font-size: 0.95rem;
  margin-bottom: 24px;
}

.hidden {
  display: none !important;
}