:root {
  --primary: #FF6B6B;
  --secondary: #4ECDC4;
  --yellow: #FFE66D;
  --bg: #F7F9FC;
  --text: #2C3E50;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background-color: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  background-color: var(--secondary);
  color: white;
  padding: 1rem;
  text-align: center;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

header h1 {
  font-size: 1.8rem;
  margin-bottom: 0.5rem;
}

nav {
  display: flex;
  justify-content: center;
  gap: 10px;
}

.nav-btn, .cat-btn {
  border: none;
  background: rgba(255, 255, 255, 0.3);
  color: white;
  padding: 8px 16px;
  border-radius: 20px;
  font-weight: bold;
  cursor: pointer;
  transition: all 0.2s ease;
}

.nav-btn.active, .cat-btn.active {
  background: white;
  color: var(--text);
  transform: scale(1.05);
}

.container {
  padding: 1.5rem;
  max-width: 900px;
  margin: 0 auto;
  width: 100%;
}

.hidden {
  display: none !important;
}

.category-selector {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.cat-btn {
  background: var(--text);
  color: white;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 15px;
}

.word-card {
  background: white;
  border-radius: 16px;
  padding: 1.2rem;
  text-align: center;
  cursor: pointer;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
}

.word-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 16px rgba(0,0,0,0.1);
}

.word-card .emoji {
  font-size: 2.5rem;
  margin-bottom: 0.3rem;
}

.word-card .english {
  font-size: 1.1rem;
  font-weight: bold;
  color: var(--primary);
  margin-bottom: 0.2rem;
}

.word-card .pronunciation {
  font-size: 0.85rem;
  font-style: italic;
  color: #8E44AD;
  background: #F4ECF7;
  padding: 2px 8px;
  border-radius: 10px;
  margin-bottom: 0.4rem;
}

.word-card .spanish {
  font-size: 0.9rem;
  color: #7F8C8D;
}

/* Quiz Styles */
.quiz-box {
  background: white;
  padding: 2rem;
  border-radius: 20px;
  text-align: center;
  box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}

.score-board {
  font-size: 1.2rem;
  font-weight: bold;
  color: var(--secondary);
  margin-bottom: 1rem;
}

.quiz-target-emoji {
  font-size: 4.5rem;
  margin: 1rem 0;
}

.options-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-top: 1.5rem;
}

.option-btn {
  background: #EAECEE;
  border: none;
  padding: 1rem;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: bold;
  cursor: pointer;
  transition: background 0.2s ease;
}

.option-btn:hover {
  background: #D5D8DC;
}