/* RESET */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  font-family: 'Poppins', sans-serif;
  background: #f5f8fd;
  color: #333;
  scroll-behavior: smooth;
}

/* NAVIGATION */
nav {
  background: #1e1e2f;
  padding: 20px 40px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 999;
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
}
nav h1 {
  color: #00d8ff;
  font-size: 1.8em;
  font-weight: 700;
}
nav ul {
  list-style: none;
  display: flex;
  gap: 30px;
}
nav ul li a {
  color: #fff;
  text-decoration: none;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 5px;
  transition: 0.3s;
}
nav ul li a:hover {
  background: #00d8ff;
  color: #1e1e2f;
}

/* MAIN */
.quiz-main {
  text-align: center;
  padding: 80px 30px;
}
.quiz-main h2 {
  font-size: 2.2em;
  margin-bottom: 50px;
  color: #2c3e50;
}

/* QUIZ BUTTONS */
.quiz-levels {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 30px;
}
.quiz-btn {
  padding: 20px 50px;
  font-size: 1.4em;
  font-weight: bold;
  border: none;
  border-radius: 50px;
  color: white;
  text-decoration: none;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.quiz-btn:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.3);
}

/* VIBRANT COLORS */
.quiz-btn.easy {
  background: linear-gradient(to right, #00c9a7, #92fe9d);
}
.quiz-btn.medium {
  background: linear-gradient(to right, #f7971e, #ffd200);
}
.quiz-btn.hard {
  background: linear-gradient(to right, #f953c6, #b91d73);
}

/* RESPONSIVE */
@media (max-width: 768px) {
  .quiz-btn {
    font-size: 1.1em;
    padding: 15px 30px;
  }
}