body {
  font-family: "Poppins", sans-serif;
  background: #0f172a;
  color: #e2e8f0;
  display: flex;
  flex-direction: column;
  align-items: center;
  min-height: 100vh;
  margin: 0;
  padding: 20px;
}

h1 {
  margin-bottom: 20px;
  text-align: center;
}

nav {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
  flex-wrap: wrap;
  justify-content: center;
}

nav button {
  background: #334155;
  border: none;
  color: white;
  padding: 8px 16px;
  border-radius: 8px;
  cursor: pointer;
  transition: 0.2s;
}

nav button.active,
nav button:hover {
  background: #06b6d4;
  color: black;
  font-weight: 600;
}

section {
  display: none;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 12px;
  padding: 20px;
  width: 360px;
  text-align: center;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
}

section.active {
  display: block;
}

input, button {
  margin: 6px;
  padding: 8px;
  border-radius: 6px;
  border: none;
  font-size: 1rem;
}

ul {
  text-align: left;
  padding-left: 20px;
}

li {
  margin: 6px 0;
  display: flex;
  justify-content: space-between;
  background: rgba(255, 255, 255, 0.08);
  padding: 6px 10px;
  border-radius: 6px;
}

.clock {
  font-size: 2rem;
  font-weight: bold;
  margin: 10px 0;
}

.quiz-options button {
  display: block;
  width: 100%;
  margin: 5px 0;
  background: #334155;
  color: white;
}

.quiz-options button:hover {
  background: #06b6d4;
  color: black;
  font-weight: 600;
}