:root {
  color-scheme: light;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: radial-gradient(circle at top left, #f5f9ff, #e8f0ff 45%, #f6f8fb);
  font-size: 20px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
}

.page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.card {
  width: min(900px, calc(100vw - 48px));
  max-width: 100%;
  background: #ffffffcc;
  backdrop-filter: blur(4px);
  border: 1px solid #dde7ff;
  border-radius: 16px;
  padding: 24px;
  box-shadow: 0 14px 40px rgba(17, 24, 39, 0.1);
  overflow: hidden;
}

h1 {
  margin-top: 0;
  margin-bottom: 8px;
  font-size: 2.3rem;
  line-height: 1.2;
}

.quiz-wrap {
  margin-top: 20px;
}

.counter {
  font-weight: 600;
  color: #2d4ea6;
  font-size: 1.35rem;
}

.question {
  margin-top: 8px;
  margin-bottom: 16px;
  line-height: 1.4;
  font-size: 1.7rem;
}

.option-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 10px;
}

.option-list li {
  list-style: none;
}

.option-label {
  font-weight: 700;
}

.hidden {
  display: none;
}

.option-btn {
  width: 100%;
  text-align: left;
  border: 1px solid #d4dffb;
  border-radius: 10px;
  padding: 12px 14px;
  background: #f7faff;
  color: #1f2937;
  cursor: pointer;
  font-weight: 500;
  font-size: 1.3rem;
  line-height: 1.4;
}

.option-btn:hover {
  background: #ecf3ff;
}

.option-btn.is-correct {
  background: #9ff7c2;
  border-color: #18a957;
  color: #064526;
  font-weight: 700;
}

.option-btn.is-wrong {
  background: #d88a8a;
  border-color: #8f1f1f;
  color: #4c0d0d;
  font-weight: 700;
}

.option-btn:disabled {
  cursor: default;
  opacity: 1;
}

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

button {
  border: none;
  border-radius: 9px;
  padding: 10px 14px;
  cursor: pointer;
  background: #2157d8;
  color: #fff;
  font-weight: 600;
  font-size: 1.15rem;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.45;
}

@media (max-width: 600px) {
  :root {
    font-size: 18px;
  }

  .card {
    padding: 16px;
  }

  button {
    width: 100%;
  }
}