/* 全局样式重置与基础配置 */
@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@300;400;500;600&family=Noto+Sans+SC:wght@300;400;500&display=swap');

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

:root {
  --color-sand: #D4C5B9;
  --color-oat: #E8DED2;
  --color-fog-blue: #A8B8C8;
  --color-terracotta: #C9A394;
  --color-black: #1A1A1A;
  --color-white: #FFFFFF;
  --color-gray-light: #F5F5F5;
  --color-gray-mid: #9E9E9E;
  --color-gray-dark: #424242;
  --transition-smooth: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  --shadow-soft: 0 4px 20px rgba(0, 0, 0, 0.08);
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'Noto Sans SC', sans-serif;
  color: var(--color-black);
  background-color: var(--color-white);
  line-height: 1.8;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Noto Serif SC', serif;
  font-weight: 400;
  letter-spacing: 0.05em;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition-smooth);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* 导航栏样式 */
.nav-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  transition: var(--transition-smooth);
}

.nav-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 1.5rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-size: 1.25rem;
  font-weight: 500;
  letter-spacing: 0.1em;
}

.nav-links {
  display: flex;
  gap: 3rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.95rem;
  letter-spacing: 0.08em;
  position: relative;
  padding: 0.5rem 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 1px;
  background-color: var(--color-black);
  transition: var(--transition-smooth);
  transform: translateX(-50%);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

/* 页面容器 */
.page-container {
  min-height: 100vh;
  padding-top: 80px;
}

/* 全屏轮播区 */
.hero-slider {
  position: relative;
  height: calc(100vh - 80px);
  overflow: hidden;
}

.slider-item {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 1s ease-in-out;
}

.slider-item.active {
  opacity: 1;
}

.slider-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.slider-indicators {
  position: absolute;
  bottom: 3rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 1rem;
  z-index: 10;
}

.indicator {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.5);
  cursor: pointer;
  transition: var(--transition-smooth);
}

.indicator.active {
  background-color: rgba(255, 255, 255, 0.95);
  transform: scale(1.2);
}

/* 引语区 */
.quote-section {
  padding: 8rem 2rem;
  text-align: center;
  background-color: var(--color-gray-light);
}

.quote-text {
  font-family: 'Noto Serif SC', serif;
  font-size: 1.8rem;
  font-weight: 300;
  letter-spacing: 0.1em;
  line-height: 2;
  max-width: 800px;
  margin: 0 auto;
  color: var(--color-gray-dark);
}

/* 主题入口卡片 */
.theme-cards {
  max-width: 1400px;
  margin: 0 auto;
  padding: 6rem 2rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 3rem;
}

.theme-card {
  position: relative;
  overflow: hidden;
  cursor: pointer;
  border-radius: 2px;
  box-shadow: var(--shadow-soft);
  transition: var(--transition-smooth);
}

.theme-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

.theme-card img {
  width: 100%;
  height: 400px;
  object-fit: cover;
  transition: var(--transition-smooth);
}

.theme-card:hover img {
  transform: scale(1.05);
}

.theme-card-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 2rem;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.7), transparent);
  color: var(--color-white);
}

.theme-card-title {
  font-size: 1.5rem;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
}

/* 分类筛选区 */
.category-filter {
  max-width: 1400px;
  margin: 0 auto;
  padding: 3rem 2rem;
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 0.8rem 2rem;
  border: 1px solid var(--color-gray-mid);
  background-color: transparent;
  color: var(--color-black);
  font-size: 0.95rem;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.filter-btn:hover,
.filter-btn.active {
  background-color: var(--color-black);
  color: var(--color-white);
  border-color: var(--color-black);
}

/* 瀑布流展示区 */
.masonry-grid {
  max-width: 1400px;
  margin: 0 auto;
  padding: 2rem;
  column-count: 3;
  column-gap: 2rem;
}

.masonry-item {
  break-inside: avoid;
  margin-bottom: 2rem;
  position: relative;
  overflow: hidden;
  cursor: pointer;
}

.masonry-item img {
  width: 100%;
  transition: var(--transition-smooth);
}

.masonry-item:hover img {
  transform: scale(1.02);
}

.masonry-caption {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 1.5rem;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
  color: var(--color-white);
  opacity: 0;
  transform: translateY(20px);
  transition: var(--transition-smooth);
  font-size: 0.9rem;
  letter-spacing: 0.05em;
}

.masonry-item:hover .masonry-caption {
  opacity: 1;
  transform: translateY(0);
}

/* 哲思页面布局 */
.philosophy-section {
  max-width: 1400px;
  margin: 0 auto;
  padding: 6rem 2rem;
}

.philosophy-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
  margin-bottom: 6rem;
}

.philosophy-text {
  padding: 2rem;
}

.philosophy-title {
  font-size: 2rem;
  margin-bottom: 2rem;
  letter-spacing: 0.1em;
}

.philosophy-body {
  font-size: 1.05rem;
  line-height: 2;
  color: var(--color-gray-dark);
  letter-spacing: 0.03em;
}

.philosophy-image {
  overflow: hidden;
  border-radius: 2px;
}

.philosophy-image img {
  width: 100%;
  height: 500px;
  object-fit: cover;
  transition: var(--transition-smooth);
}

.philosophy-image:hover img {
  transform: scale(1.05);
}

/* 页脚样式 */
.footer {
  text-align: center;
  padding: 3rem 2rem;
  background-color: var(--color-gray-light);
  color: var(--color-gray-mid);
  font-size: 0.9rem;
  letter-spacing: 0.1em;
}

/* 返回顶部按钮 */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 50px;
  height: 50px;
  background-color: var(--color-black);
  color: var(--color-white);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition-smooth);
  z-index: 999;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
}

.back-to-top.visible {
  opacity: 0.8;
  visibility: visible;
}

.back-to-top:hover {
  opacity: 1;
  transform: translateY(-4px);
}

/* 渐入动画 */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 响应式设计 */
@media (max-width: 1024px) {
  .masonry-grid {
    column-count: 2;
  }
  
  .philosophy-content {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

@media (max-width: 768px) {
  .nav-links {
    gap: 1.5rem;
  }
  
  .nav-links a {
    font-size: 0.85rem;
  }
  
  .quote-text {
    font-size: 1.3rem;
  }
  
  .theme-cards {
    grid-template-columns: 1fr;
    padding: 4rem 1.5rem;
  }
  
  .masonry-grid {
    column-count: 1;
    padding: 1.5rem;
  }
  
  .philosophy-section {
    padding: 4rem 1.5rem;
  }
  
  .philosophy-title {
    font-size: 1.5rem;
  }
  
  .philosophy-body {
    font-size: 1rem;
  }
}

@media (max-width: 480px) {
  .nav-container {
    padding: 1rem 1.5rem;
  }
  
  .nav-links {
    gap: 1rem;
  }
  
  .category-filter {
    gap: 1rem;
  }
  
  .filter-btn {
    padding: 0.6rem 1.5rem;
    font-size: 0.85rem;
  }
}