/* 新幹線 STEM 探險 - 小學生友善樣式 */
:root {
  --yellow: #FFD700;
  --blue: #0057A8;
  --dark: #1a1a2e;
  --light: #f8f9fa;
  --green: #28a745;
  --orange: #fd7e14;
  --red: #dc3545;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: "Helvetica Neue", "微軟正黑體", "Microsoft JhengHei", sans-serif;
  line-height: 1.6;
  color: #333;
  background: #fff;
}

/* 導覽列 */
.navbar {
  background: var(--blue);
  color: white;
  padding: 0.8rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.logo {
  font-size: 1.4rem;
  font-weight: bold;
}

.nav-links {
  list-style: none;
  display: flex;
  gap: 1.2rem;
  flex-wrap: wrap;
}

.nav-links a {
  color: white;
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--yellow);
}

/* 英雄區 */
.hero {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  background: linear-gradient(135deg, #0057A8 0%, #003d75 100%);
  color: white;
  padding: 2.5rem 1.5rem;
  gap: 2rem;
}

.hero-content {
  flex: 1 1 320px;
}

.hero h1 {
  font-size: 2.2rem;
  margin-bottom: 1rem;
  color: var(--yellow);
}

.hero p {
  font-size: 1.15rem;
  margin-bottom: 1.5rem;
}

.hero-image {
  flex: 1 1 320px;
  text-align: center;
}

.hero-image img {
  max-width: 100%;
  border-radius: 12px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.3);
}

/* 按鈕 */
.btn {
  display: inline-block;
  background: var(--yellow);
  color: var(--dark);
  padding: 0.7rem 1.5rem;
  border-radius: 50px;
  text-decoration: none;
  font-weight: bold;
  border: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
}

.btn.small {
  padding: 0.4rem 1rem;
  font-size: 0.9rem;
}

/* STEM 卡片 */
.stem-intro {
  padding: 2.5rem 1.5rem;
  background: #f0f7ff;
  text-align: center;
}

.stem-intro h2 {
  margin-bottom: 1.5rem;
  color: var(--blue);
}

.stem-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1.2rem;
  max-width: 1000px;
  margin: 0 auto;
}

.stem-card {
  background: white;
  border-radius: 16px;
  padding: 1.5rem;
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
  transition: transform 0.2s;
}

.stem-card:hover {
  transform: translateY(-5px);
}

.stem-card .emoji {
  font-size: 2.5rem;
}

.stem-card h3 {
  margin: 0.5rem 0;
  color: var(--blue);
}

.science { border-top: 5px solid #6f42c1; }
.tech { border-top: 5px solid #20c997; }
.eng { border-top: 5px solid #fd7e14; }
.math { border-top: 5px solid #e83e8c; }

/* 通用區塊 */
.section {
  padding: 2.5rem 1.5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.section.alt {
  background: #f8f9fa;
  max-width: 100%;
}

.section.alt > * {
  max-width: 1100px;
  margin-left: auto;
  margin-right: auto;
}

.section h2 {
  color: var(--blue);
  margin-bottom: 1rem;
  font-size: 1.8rem;
}

.lead {
  font-size: 1.15rem;
  margin-bottom: 1.5rem;
  color: #555;
}

/* 圖片框 */
.image-box {
  margin: 1.5rem 0;
  text-align: center;
}

.image-box img {
  max-width: 100%;
  border-radius: 12px;
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
}

.caption {
  font-size: 0.9rem;
  color: #666;
  margin-top: 0.5rem;
}

/* 車廂網格 */
.car-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}

.car-card {
  background: #fffbe6;
  border: 2px solid var(--yellow);
  border-radius: 12px;
  padding: 1rem;
  text-align: center;
  font-size: 0.9rem;
}

.car-num {
  background: var(--yellow);
  color: var(--dark);
  font-weight: bold;
  border-radius: 8px;
  padding: 0.3rem;
  margin-bottom: 0.5rem;
}

/* 趣味知識 */
.fun-fact {
  background: #e8f5e9;
  border-left: 6px solid var(--green);
  padding: 1rem 1.2rem;
  border-radius: 0 12px 12px 0;
  margin: 1.5rem 0;
}

/* 檢查項目 */
.inspect-table {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.2rem;
  margin: 1.5rem 0;
}

.inspect-item {
  background: white;
  border-radius: 12px;
  padding: 1.2rem;
  box-shadow: 0 3px 10px rgba(0,0,0,0.08);
}

.inspect-item h4 {
  margin-bottom: 0.5rem;
}

.inspect-item .place {
  font-size: 0.85rem;
  color: #777;
  margin-top: 0.5rem;
}

/* 數學框 */
.math-box {
  background: #fff3cd;
  border: 2px dashed #ffc107;
  border-radius: 12px;
  padding: 1.5rem;
  margin: 1.5rem 0;
  text-align: center;
}

.hint {
  color: #856404;
  font-size: 0.95rem;
}

.answer {
  margin-top: 1rem;
  font-weight: bold;
  color: var(--green);
}

.hidden {
  display: none;
}

/* 比較卡 */
.compare-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin: 1.5rem 0;
}

.compare-card {
  background: white;
  border-radius: 12px;
  padding: 1.2rem;
  box-shadow: 0 3px 12px rgba(0,0,0,0.1);
  text-align: center;
}

.compare-card img {
  max-width: 100%;
  border-radius: 8px;
  margin: 0.8rem 0;
}

.compare-card ul {
  list-style: none;
  text-align: left;
  padding-left: 0.5rem;
}

.compare-card li {
  margin: 0.4rem 0;
  position: relative;
  padding-left: 1.2rem;
}

.compare-card li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--green);
  font-weight: bold;
}

/* 生命週期步驟 */
.cycle-steps {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  justify-content: center;
  margin: 1.5rem 0;
}

.step {
  background: var(--blue);
  color: white;
  padding: 0.8rem 1rem;
  border-radius: 12px;
  text-align: center;
  min-width: 120px;
  font-size: 0.9rem;
}

.step small {
  display: block;
  opacity: 0.85;
  font-size: 0.8rem;
}

/* 塗裝步驟 */
.paint-steps {
  background: white;
  border-radius: 12px;
  padding: 1.5rem 2rem;
  box-shadow: 0 3px 10px rgba(0,0,0,0.08);
  margin: 1.5rem 0;
}

.paint-steps li {
  margin: 0.8rem 0;
  font-size: 1.05rem;
}

/* 測驗 */
.quiz-container {
  max-width: 700px;
  margin: 0 auto;
}

.quiz-q {
  background: white;
  border-radius: 12px;
  padding: 1.2rem;
  margin-bottom: 1.2rem;
  box-shadow: 0 3px 10px rgba(0,0,0,0.08);
}

.quiz-q p {
  font-weight: bold;
  margin-bottom: 0.8rem;
}

.quiz-q button {
  display: block;
  width: 100%;
  text-align: left;
  padding: 0.6rem 1rem;
  margin: 0.4rem 0;
  border: 2px solid #ddd;
  border-radius: 8px;
  background: #f8f9fa;
  cursor: pointer;
  transition: all 0.2s;
}

.quiz-q button:hover {
  border-color: var(--blue);
  background: #e8f0fe;
}

.quiz-q button.correct {
  background: #d4edda;
  border-color: var(--green);
}

.quiz-q button.wrong {
  background: #f8d7da;
  border-color: var(--red);
}

.score {
  text-align: center;
  font-size: 1.2rem;
  font-weight: bold;
  margin-top: 1rem;
  color: var(--blue);
}

/* 頁尾 */
.footer {
  background: var(--dark);
  color: white;
  text-align: center;
  padding: 2.5rem 1.5rem;
}

.footer h2 {
  color: var(--yellow);
  margin-bottom: 1rem;
}

.credit {
  margin-top: 1.5rem;
  font-size: 0.85rem;
  opacity: 0.7;
}

/* 響應式 */
@media (max-width: 700px) {
  .navbar {
    flex-direction: column;
    gap: 0.5rem;
  }
  .nav-links {
    justify-content: center;
  }
  .hero h1 {
    font-size: 1.7rem;
  }
}

/* 環保區塊 */
.eco-list {
  list-style: none;
  background: #e8f5e9;
  border-radius: 12px;
  padding: 1.2rem 1.5rem;
  margin: 1rem 0 1.5rem;
  font-size: 1.05rem;
}

.eco-list li {
  margin: 0.5rem 0;
}

.eco-highlight {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.2rem;
  margin: 1.5rem 0;
}

.eco-box {
  background: linear-gradient(135deg, #e8f5e9, #c8e6c9);
  border: 2px solid var(--green);
  border-radius: 16px;
  padding: 1.5rem;
  text-align: center;
}

.eco-box h4 {
  color: #2e7d32;
  margin-bottom: 0.5rem;
}

.eco-box strong {
  font-size: 1.4rem;
  color: #1b5e20;
}

/* 錨點跳轉避開 sticky 導覽列 */
html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

/* 手機：導覽橫向捲動單行，唔好 wrap 成 5 行（原本 navbar 高 229px，霸咗 1/4 畫面） */
@media (max-width: 700px) {
  .nav-links {
    flex-wrap: nowrap;
    overflow-x: auto;
    justify-content: flex-start;
    width: 100%;
    padding-bottom: 4px;
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
  }
  .nav-links::-webkit-scrollbar { display: none; }
  .nav-links a { white-space: nowrap; }
  html { scroll-padding-top: 128px; }
}