:root {
  --pink: #ffd6e8;
  --blue: #cbe7ff;
  --mint: #c7f5e8;
  --lav: #e4dcff;
  --text: #30435c;
  --accent: #6c8cff;
  --correct: #6ad29c;
  --wrong: #ff7b7b;
  --card-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, sans-serif;
  background: radial-gradient(circle at 20% 20%, var(--pink), transparent 35%),
    radial-gradient(circle at 80% 10%, var(--blue), transparent 30%),
    radial-gradient(circle at 50% 80%, var(--lav), transparent 35%),
    #f7fbff;
  color: var(--text);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 16px;
}

.glass {
  width: min(100%, 960px);
  background: rgba(255, 255, 255, 0.78);
  backdrop-filter: blur(12px);
  border-radius: 24px;
  box-shadow: var(--card-shadow);
  padding: 20px;
  position: relative;
  overflow: hidden;
}

.float-bg {
  position: absolute;
  inset: 0;
  background: radial-gradient(120px 120px at 15% 30%, rgba(255, 255, 255, 0.5), transparent),
    radial-gradient(200px 200px at 80% 20%, rgba(255, 255, 255, 0.5), transparent);
  pointer-events: none;
  animation: shimmer 12s ease-in-out infinite alternate;
}

@keyframes shimmer {
  from {
    transform: translateY(0px);
    opacity: 0.8;
  }
  to {
    transform: translateY(8px);
    opacity: 1;
  }
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.brand {
  font-weight: 800;
  letter-spacing: 0.5px;
}

main {
  position: relative;
  z-index: 1;
}

.panel {
  margin-top: 24px;
  background: rgba(255, 255, 255, 0.8);
  border-radius: 16px;
  padding: 20px;
  box-shadow: var(--card-shadow);
}

.panel.center {
  text-align: center;
}

.lede {
  color: #5f6f93;
  max-width: 680px;
  margin: 12px auto 24px;
}

.btn {
  border: none;
  border-radius: 12px;
  padding: 12px 18px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, opacity 0.2s;
  background: linear-gradient(135deg, var(--blue), var(--mint));
  color: var(--text);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.16);
}

.btn:active {
  transform: translateY(0);
}

.btn.secondary {
  background: linear-gradient(135deg, #ffe0f2, #f7f0ff);
}

.btn.ghost {
  background: transparent;
  box-shadow: none;
  border: 1px solid #d8e4ff;
}

.fade {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.35s ease, transform 0.35s ease;
}

.fade.show {
  opacity: 1;
  transform: translateY(0);
}

.status {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.badge {
  display: inline-block;
  padding: 6px 12px;
  border-radius: 12px;
  background: #f0f4ff;
  color: #52608c;
  font-weight: 700;
}

.tiny {
  color: #6b7aa8;
  font-weight: 700;
}

.progress-bar {
  width: 100%;
  height: 12px;
  border-radius: 999px;
  background: #e8f0ff;
  overflow: hidden;
  margin-top: 8px;
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.08);
}

.progress-fill {
  height: 100%;
  background: linear-gradient(135deg, var(--accent), #9ad2ff);
  width: 0%;
  transition: width 0.25s ease;
}

.question-card {
  background: white;
  border-radius: 18px;
  padding: 18px;
  box-shadow: var(--card-shadow);
  margin-top: 18px;
  position: relative;
}

.options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
  margin-top: 14px;
}

.option {
  border: 1px solid #d9e4ff;
  border-radius: 14px;
  padding: 14px;
  background: #f7fbff;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease, background 0.2s ease;
  position: relative;
  overflow: hidden;
  text-align: left;
}

.option:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.08);
}

.option.correct {
  border-color: var(--correct);
  background: linear-gradient(135deg, #e9fff3, #f5fffb);
}

.option.wrong {
  border-color: var(--wrong);
  background: linear-gradient(135deg, #ffe9e9, #fff7f7);
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 18px;
  gap: 12px;
  flex-wrap: wrap;
}

.review-list {
  margin-top: 24px;
  display: grid;
  gap: 14px;
}

.review-card {
  padding: 18px;
  border-radius: 14px;
  background: white;
  box-shadow: var(--card-shadow);
  text-align: left;
}

.review-card ul {
  list-style: none;
  padding: 0;
  margin: 12px 0 0 0;
}

.review-card li {
  margin: 6px 0;
  padding: 8px 10px;
  border-radius: 10px;
  background: #f9fbff;
}

.answer-highlight {
  color: var(--accent);
  font-weight: 800;
}

@media (max-width: 640px) {
  .options {
    grid-template-columns: 1fr;
  }

  .btn {
    width: 100%;
    text-align: center;
  }

  header {
    justify-content: center;
  }
}