:root {
  --bg-dark: #071a2e;
  --bg-mid: #10355b;
  --accent: #ffb703;
  --accent-strong: #fb8500;
  --text-main: #f8fbff;
  --card-bg: rgba(3, 17, 32, 0.88);
  --ok: #00d084;
  --bad: #ff5f6d;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
  background:
    radial-gradient(circle at 15% 0%, #1e4f80, transparent 42%),
    radial-gradient(circle at 85% 0%, #4f1f85, transparent 35%),
    linear-gradient(170deg, var(--bg-mid), var(--bg-dark) 60%);
  color: var(--text-main);
  min-height: 100vh;
  padding: 1.25rem;
}

.page-shell {
  max-width: 1080px;
  margin: 0 auto;
}

.top-banner {
  text-align: center;
  margin-bottom: 1rem;
}

.top-banner h1 {
  margin: 0;
  font-size: clamp(1.6rem, 2.4vw, 2.5rem);
}

.top-banner p {
  margin-top: 0.4rem;
  color: #d6e8f8;
}

.card {
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 16px;
  background: var(--card-bg);
  box-shadow: 0 14px 24px rgba(0, 0, 0, 0.35);
  padding: 1.25rem;
}

.screen {
  display: none;
}

.screen.active {
  display: block;
}

.setup-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.2rem;
  align-items: center;
}

.setup-form {
  max-width: 360px;
}

.setup-form h2 {
  margin-top: 0;
}

label {
  display: block;
  margin-top: 0.7rem;
  margin-bottom: 0.2rem;
  font-size: 0.95rem;
}

select,
input {
  width: 100%;
  max-width: 320px;
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: #ffffff;
  color: #081420;
  padding: 0.58rem 0.7rem;
  font-size: 0.95rem;
}

.setup-hero {
  justify-self: end;
}

.setup-hero img {
  width: min(500px, 100%);
  border-radius: 14px;
  border: 2px solid rgba(255, 255, 255, 0.3);
}

.primary-btn,
.secondary-btn {
  border: 0;
  border-radius: 10px;
  padding: 0.66rem 1rem;
  margin-top: 1rem;
  font-weight: 700;
  cursor: pointer;
}

.primary-btn {
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: #1e1b13;
}

.secondary-btn {
  background: #dbe6f0;
  color: #0d233d;
}

.secondary-btn:disabled,
.primary-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.error-text {
  min-height: 1.25rem;
  color: #ffb7be;
}

.quiz-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.7rem;
}

.topic-pill {
  border: 1px solid rgba(255, 255, 255, 0.5);
  border-radius: 999px;
  padding: 0.25rem 0.7rem;
  color: #d7ebff;
  margin: 0;
}

.question-image-wrap {
  margin-top: 0.6rem;
  margin-bottom: 0.9rem;
  background: #fff;
  border-radius: 10px;
  padding: 0.65rem;
}

.question-image-wrap img {
  max-width: 100%;
  max-height: 260px;
  margin: 0 auto;
  display: block;
}

#question-text {
  line-height: 1.45;
  font-size: 1.2rem;
}

.answer-row {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.answer-row input {
  max-width: 360px;
}

.unit-label {
  color: #dcefff;
  min-width: 68px;
}

.actions-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 0.75rem;
}

.actions-row button {
  margin-top: 0;
}

.hint-text {
  background: rgba(255, 255, 255, 0.1);
  border-left: 4px solid var(--accent);
  border-radius: 7px;
  padding: 0.7rem;
  margin-top: 0.85rem;
}

.feedback-wrap {
  margin-top: 0.95rem;
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding: 0.65rem;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.08);
}

.feedback-wrap img {
  width: 42px;
  height: 42px;
  object-fit: contain;
  border-radius: 8px;
}

.feedback-wrap.correct {
  border: 1px solid rgba(0, 208, 132, 0.6);
}

.feedback-wrap.incorrect {
  border: 1px solid rgba(255, 95, 109, 0.65);
}

.summary-message {
  font-size: 1.05rem;
}

.summary-actions-row {
  display: flex;
  align-items: flex-start;
  gap: 0.9rem;
  flex-wrap: wrap;
}

.summary-gif {
  width: min(420px, 100%);
  border-radius: 12px;
  margin: 0.8rem 0;
}

.summary-back-btn {
  margin-top: 0.8rem;
}

.quit-btn {
  margin-left: auto;
}

.footer-copy {
  text-align: center;
  margin-top: 0.9rem;
  color: #d6e8f8;
  font-size: 0.92rem;
}

.hidden {
  display: none;
}

@media (max-width: 860px) {
  .setup-grid {
    grid-template-columns: 1fr;
  }

  .setup-form {
    max-width: 100%;
  }

  .setup-hero {
    justify-self: stretch;
  }

  .summary-back-btn {
    margin-top: 0.2rem;
  }
}