/* ========== 基础重置与变量 ========== */
:root {
  /* 配色 - 参考 Silent Curator 风格 */
  --color-bg: #f9f9f9;
  --color-surface: #ffffff;
  --color-surface-hover: #f3f3f3;
  --color-surface-container: #eeeeee;
  --color-surface-container-low: #f3f3f3;
  --color-border: #c1c8c4;
  --color-border-light: #e2e2e2;
  --color-text: #1a1c1c;
  --color-text-secondary: #414845;
  --color-text-muted: #717975;
  --color-primary: #17362e;
  --color-primary-container: #2e4d44;
  --color-primary-light: rgba(23, 54, 46, 0.06);
  --color-primary-fixed: #c7eade;
  --color-on-primary: #ffffff;
  --color-card-bg: #ffffff;

  /* 字体 */
  --font-serif: 'Newsreader', 'Noto Serif SC', Georgia, serif;
  --font-sans: 'Manrope', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;

  /* 圆角 - 更精致 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  /* 阴影 - 更克制 */
  --shadow-sm: 0 1px 3px rgba(26, 28, 28, 0.04);
  --shadow-md: 0 4px 12px rgba(26, 28, 28, 0.06);
  --shadow-lg: 0 12px 32px -4px rgba(26, 28, 28, 0.08);

  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== 导航栏 ========== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: var(--transition);
  background: rgba(249, 249, 249, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
}

.navbar.scrolled {
  border-bottom-color: var(--color-border-light);
  box-shadow: 0 1px 2px rgba(26, 28, 28, 0.04);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 500;
  font-style: italic;
  letter-spacing: -0.01em;
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  gap: 32px;
}

.nav-link {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  font-weight: 500;
  position: relative;
  letter-spacing: 0.02em;
}

.nav-link:hover {
  color: var(--color-primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--color-primary);
  transition: var(--transition);
}

.nav-link:hover::after {
  width: 100%;
}

.nav-cta {
  font-size: 0.8rem;
  padding: 8px 20px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  transition: var(--transition);
}

.nav-cta:hover {
  border-color: var(--color-primary);
  color: var(--color-on-primary);
  background: var(--color-primary);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--color-text);
  transition: var(--transition);
}

.mobile-menu {
  display: none;
  flex-direction: column;
  padding: 20px 24px;
  gap: 16px;
  background: var(--color-bg);
}

.mobile-menu.active {
  display: flex;
}

.mobile-link {
  font-size: 1rem;
  color: var(--color-text-secondary);
  padding: 8px 0;
  border-bottom: 1px solid var(--color-border-light);
  font-weight: 500;
}

.mobile-link:hover {
  color: var(--color-primary);
}

/* ========== Hero ========== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 80px;
  position: relative;
  overflow: hidden;
  background-image: radial-gradient(circle, var(--color-border) 1px, transparent 1px);
  background-size: 32px 32px;
  background-position: center center;
}

/* 网格渐隐遮罩：四周淡出 */
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 70% 60% at 50% 45%, transparent 30%, var(--color-bg) 75%);
  pointer-events: none;
  z-index: 0;
}

/* 装饰光点 */
.hero::after {
  content: '';
  position: absolute;
  width: 480px;
  height: 480px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(199, 234, 222, 0.35) 0%, transparent 70%);
  top: 15%;
  left: 50%;
  transform: translateX(-50%);
  pointer-events: none;
  z-index: 0;
}

.hero-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  position: relative;
  z-index: 1;
}

.hero-content {
  max-width: 840px;
  text-align: center;
}

.hero-greeting {
  font-size: 1.5rem;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
  font-weight: 400;
  font-family: var(--font-sans);
}

.hero-name {
  color: var(--color-primary);
  font-weight: 600;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: 4.8rem;
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.12;
  margin-bottom: 28px;
  color: var(--color-text);
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--color-text-secondary);
  line-height: 1.9;
  margin-bottom: 44px;
  font-weight: 400;
}

.hero-subtitle strong {
  color: var(--color-primary);
  font-weight: 600;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}

/* Hero 入场动画 */
.hero-anim {
  opacity: 0;
  transform: translateY(20px);
  animation: heroFadeIn 0.7s ease forwards;
}

.hero-anim:nth-child(1) { animation-delay: 0.1s; }
.hero-anim:nth-child(2) { animation-delay: 0.25s; }
.hero-anim:nth-child(3) { animation-delay: 0.4s; }
.hero-anim:nth-child(4) { animation-delay: 0.55s; }

@keyframes heroFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ========== 按钮 ========== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  transition: var(--transition);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: linear-gradient(135deg, #17362e 0%, #2e4d44 100%);
  color: var(--color-on-primary);
  box-shadow: 0 2px 8px rgba(23, 54, 46, 0.2);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(23, 54, 46, 0.3);
}

.btn-secondary {
  background: transparent;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-2px);
}

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  color: var(--color-primary);
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition: var(--transition);
}

.link-arrow::after {
  content: '\2192';
  transition: var(--transition);
  font-size: 0.9em;
}

.link-arrow:hover {
  color: var(--color-primary-container);
}

.link-arrow:hover::after {
  transform: translateX(4px);
}

/* ========== 作品概览 ========== */
.work-overview {
  padding: 80px 0;
}

.overview-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.overview-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 40px;
  transition: var(--transition);
  cursor: pointer;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.overview-card:hover {
  border-color: var(--color-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.overview-card--large {
  grid-column: 1 / -1;
}

.overview-card h3 {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  font-weight: 500;
  font-style: italic;
  margin-bottom: 12px;
  color: var(--color-text);
}

.overview-card p {
  color: var(--color-text-secondary);
  margin-bottom: 20px;
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ========== 关于我简介 ========== */
.about-brief {
  padding: 120px 0;
  text-align: center;
}

/* ========== 关于我详情 ========== */
.about-detail {
  padding: 100px 0;
}

.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 80px;
  align-items: start;
}

.about-intro .section-label {
  text-align: left;
}

.about-detail-title {
  font-family: var(--font-serif);
  font-size: 2.2rem;
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.3;
  margin-bottom: 32px;
  color: var(--color-text);
}

.about-text p {
  color: var(--color-text-secondary);
  line-height: 1.9;
  margin-bottom: 20px;
  font-size: 0.95rem;
}

.about-text p:last-child {
  margin-bottom: 0;
}

.about-sidebar {
  display: flex;
  flex-direction: column;
  gap: 36px;
}

.about-block-title {
  font-size: 0.65rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  margin-bottom: 16px;
  font-weight: 700;
}

.experience-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.experience-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.experience-role {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-text);
}

.experience-company {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

.experience-period {
  font-size: 0.75rem;
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.skill-tag {
  font-size: 0.7rem;
  padding: 5px 14px;
  background: var(--color-primary-light);
  border: 1px solid rgba(23, 54, 46, 0.08);
  border-radius: var(--radius-md);
  color: var(--color-primary);
  font-weight: 600;
  letter-spacing: 0.02em;
}

.section-label {
  font-size: 0.7rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  margin-bottom: 24px;
  font-weight: 700;
}

.about-headline {
  font-family: var(--font-serif);
  font-size: 2.8rem;
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1.3;
  margin-bottom: 24px;
  color: var(--color-text);
}

.about-desc {
  font-size: 1.05rem;
  color: var(--color-text-secondary);
  line-height: 1.9;
  max-width: 580px;
  margin: 0 auto 40px;
  font-weight: 400;
}

/* ========== 作品展示 ========== */
.work {
  padding: 100px 0;
}

.section-title {
  font-family: var(--font-serif);
  font-size: 2rem;
  font-weight: 400;
  font-style: italic;
  margin-bottom: 60px;
  letter-spacing: -0.01em;
}

.section-subtitle {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  color: var(--color-text-muted);
  font-weight: 400;
  font-style: normal;
}

.work-timeline {
  position: relative;
}

.work-year {
  margin-bottom: 24px;
  margin-top: 60px;
}

.work-year:first-child {
  margin-top: 0;
}

.year-label {
  font-size: 0.7rem;
  color: var(--color-primary);
  font-weight: 700;
  padding: 6px 16px;
  background: var(--color-primary-light);
  border-radius: var(--radius-md);
  border: 1px solid rgba(23, 54, 46, 0.1);
  display: inline-block;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.work-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  overflow: hidden;
  margin-bottom: 24px;
  transition: var(--transition);
  display: flex;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  text-decoration: none;
  color: inherit;
}

.work-card:hover {
  border-color: var(--color-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.work-card-image {
  width: 45%;
  min-height: 280px;
  flex-shrink: 0;
  overflow: hidden;
}

.work-card-image img {
  width: 100%;
  height: 100%;
  min-height: 280px;
  object-fit: cover;
  display: block;
}

.image-placeholder {
  width: 100%;
  height: 100%;
  min-height: 280px;
  background: linear-gradient(135deg, var(--color-surface-container-low) 0%, var(--color-border-light) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

.work-card-content {
  padding: 40px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.work-card-content h3 {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 500;
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.work-card-content p {
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 24px;
  font-size: 0.9rem;
}

/* ========== 其他项目 ========== */
.other-things {
  padding: 100px 0;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--color-text-secondary);
  margin-bottom: 60px;
  line-height: 1.9;
}

.project-highlight {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 48px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.project-highlight h3 {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 500;
  font-style: italic;
  margin-bottom: 32px;
}

.app-showcase {
  display: flex;
  gap: 16px;
  margin-bottom: 32px;
  flex-wrap: wrap;
}

.app-card {
  background: var(--color-surface-container-low);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 24px;
  text-align: center;
  min-width: 160px;
  transition: var(--transition);
}

.app-card:hover {
  border-color: var(--color-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.app-icon-placeholder {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, #c7eade 0%, #accec2 100%);
  border-radius: var(--radius-md);
  margin: 0 auto 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  color: var(--color-primary);
  font-weight: 700;
}

.app-card span {
  font-weight: 600;
  font-size: 0.85rem;
  display: block;
  margin-bottom: 4px;
}

.app-card p {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

/* ========== App Spotlight (DramaForge) ========== */
.app-spotlight {
  background: var(--color-surface-container-low);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  padding: 36px;
  margin-bottom: 32px;
}

.app-spotlight-header {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 22px;
  flex-wrap: wrap;
}

.app-spotlight-icon {
  width: 64px;
  height: 64px;
  border-radius: 14px;
  flex-shrink: 0;
  display: block;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

.app-spotlight-meta {
  flex: 1;
  min-width: 220px;
}

.app-spotlight-meta h4 {
  font-size: 1.15rem;
  font-weight: 700;
  margin: 0 0 4px;
  color: var(--color-text-primary);
}

.app-spotlight-tagline {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin: 0;
}

.app-spotlight-credits {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  background: #0a0a0a;
  color: #DCFF00;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.app-spotlight-credits .credits-icon {
  font-size: 0.95rem;
  line-height: 1;
}

.app-spotlight-pitch {
  margin-bottom: 28px;
}

.app-spotlight-pitch p {
  font-size: 0.92rem;
  line-height: 1.85;
  color: var(--color-text-secondary);
  margin: 0 0 10px;
}

.app-spotlight-pitch p:last-child {
  margin-bottom: 0;
}

.app-spotlight-screens {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  margin-bottom: 28px;
}

.phone-screen {
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.iphone-frame {
  padding: 6px;
  background: #0a0a0a;
  border-radius: 32px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.18), 0 0 0 1px rgba(0, 0, 0, 0.06);
  width: 100%;
  overflow: hidden;
}

.iphone-frame img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 26px;
  background: #000;
}

.phone-screen figcaption {
  text-align: center;
  font-size: 0.74rem;
  color: var(--color-text-muted);
  margin-top: 12px;
  letter-spacing: 0.02em;
}

.app-spotlight-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 22px;
}

.app-tag {
  padding: 6px 12px;
  background: var(--color-surface-container);
  border: 1px solid var(--color-border-light);
  border-radius: 999px;
  font-size: 0.75rem;
  color: var(--color-text-secondary);
  font-weight: 500;
}

.app-spotlight-note {
  font-size: 0.8rem;
  line-height: 1.75;
  color: var(--color-text-muted);
  padding-top: 18px;
  border-top: 1px dashed var(--color-border-light);
  margin: 0;
}

.app-spotlight-note strong {
  color: var(--color-text-secondary);
  font-weight: 600;
}

@media (max-width: 768px) {
  .app-spotlight {
    padding: 24px;
  }
  .app-spotlight-screens {
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
  }
  .app-spotlight-credits {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .app-spotlight {
    padding: 20px;
  }
  .app-spotlight-screens {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }
  .iphone-frame {
    border-radius: 26px;
    padding: 5px;
  }
  .iphone-frame img {
    border-radius: 21px;
  }
}

/* ========== 文章 ========== */
.writings {
  padding: 100px 0;
}

.writings-intro {
  font-family: var(--font-serif);
  font-size: 1.8rem;
  font-weight: 400;
  font-style: italic;
  margin-bottom: 16px;
}

.writings-all {
  margin-bottom: 48px;
  display: inline-block;
}

.writings-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-bottom: 48px;
}

.writing-card {
  display: block;
  color: inherit;
  text-decoration: none;
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: var(--transition);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
}

.writing-card:hover {
  border-color: var(--color-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.writing-image {
  height: 150px;
  overflow: hidden;
}

.writing-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: grayscale(30%) brightness(0.95) contrast(1.05);
  transition: filter 0.3s ease;
}

.writing-card:hover .writing-image img {
  filter: grayscale(0%) brightness(1) contrast(1);
}

.writing-image .image-placeholder {
  min-height: 150px;
  background: linear-gradient(135deg, var(--color-surface-container-low) 0%, var(--color-surface-container) 100%);
  font-size: 0.8rem;
  color: var(--color-primary);
  font-weight: 600;
}

.writing-content {
  padding: 20px;
}

.writing-reads {
  display: none;
}

.writing-content h4 {
  font-family: var(--font-serif);
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 8px;
  line-height: 1.5;
  color: var(--color-text);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.writing-content p {
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  margin-bottom: 14px;
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.writing-tags {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.tag {
  font-size: 0.65rem;
  padding: 3px 10px;
  background: var(--color-primary-light);
  border: 1px solid rgba(23, 54, 46, 0.08);
  border-radius: var(--radius-md);
  color: var(--color-primary);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ========== 演讲 ========== */
.talks {
  padding: 100px 0;
}

.talks-intro {
  font-family: var(--font-serif);
  font-size: 1.8rem;
  font-weight: 400;
  font-style: italic;
  margin-bottom: 16px;
}

.talks-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin: 48px 0;
}

.talk-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 32px;
  transition: var(--transition);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
}

.talk-card:hover {
  border-color: var(--color-border);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.talk-date {
  font-size: 0.65rem;
  color: var(--color-text-muted);
  margin-bottom: 8px;
  display: block;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  font-weight: 700;
}

.talk-card h4 {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 500;
  margin-bottom: 8px;
}

.talk-card p {
  color: var(--color-text-secondary);
  font-size: 0.85rem;
  margin-bottom: 16px;
  line-height: 1.7;
}

.talk-tags {
  display: flex;
  gap: 6px;
}

/* ========== 合作邀请 ========== */
.collaboration {
  padding: 120px 0;
  text-align: center;
}

.collab-title {
  font-family: var(--font-serif);
  font-size: 2.5rem;
  font-weight: 400;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.collab-motto {
  font-size: 1rem;
  color: var(--color-text-secondary);
  margin-bottom: 60px;
  font-weight: 400;
}

.collab-content {
  max-width: 640px;
  margin: 0 auto 60px;
  text-align: left;
}

.collab-letter h3 {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  font-weight: 500;
  font-style: italic;
  margin-bottom: 8px;
}

.collab-letter h3 span {
  color: var(--color-text-muted);
  font-weight: 400;
  font-size: 0.9rem;
  font-style: normal;
  font-family: var(--font-sans);
}

.collab-letter > p {
  color: var(--color-text-secondary);
  margin-bottom: 24px;
  font-size: 0.9rem;
}

.letter-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  padding: 40px;
  position: relative;
  box-shadow: var(--shadow-sm);
}

.letter-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 40px;
  right: 40px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-border-light), transparent);
}

.letter-card p {
  color: var(--color-text-secondary);
  margin-bottom: 16px;
  line-height: 1.9;
  font-size: 0.9rem;
}

.letter-greeting {
  color: var(--color-text) !important;
  font-weight: 600;
}

.letter-sign {
  margin-top: 24px;
  color: var(--color-primary) !important;
  font-family: var(--font-serif);
  font-style: italic;
}

.connect-links {
  margin-top: 60px;
}

.connect-links h3 {
  font-family: var(--font-serif);
  font-size: 1.3rem;
  font-weight: 500;
  font-style: italic;
  margin-bottom: 24px;
}

.connect-grid {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.connect-btn {
  padding: 10px 24px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  transition: var(--transition);
  cursor: pointer;
  background: transparent;
  font-family: var(--font-sans);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.connect-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-on-primary);
  background: var(--color-primary);
}

.mentor-note {
  color: var(--color-text-muted);
  font-size: 0.85rem;
  margin-bottom: 12px;
}

/* ========== 页脚 ========== */
.footer {
  padding: 60px 0 40px;
  border-top: 1px solid var(--color-border-light);
}

.footer-grid {
  display: flex;
  justify-content: space-between;
  gap: 60px;
  flex-wrap: wrap;
}

.footer-nav, .footer-links {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-nav h4, .footer-links h4 {
  font-size: 0.65rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  margin-bottom: 8px;
  font-weight: 700;
}

.footer-nav a, .footer-links a, .footer-link-btn {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

.footer-nav a:hover, .footer-links a:hover, .footer-link-btn:hover {
  color: var(--color-primary);
}

.footer-link-btn {
  background: none;
  border: none;
  padding: 0;
  font-family: inherit;
  text-align: left;
  cursor: pointer;
}

.footer-copy {
  display: flex;
  align-items: flex-end;
}

.footer-copy p {
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

/* ========== 微信二维码弹窗 ========== */
.qr-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 1000;
  align-items: center;
  justify-content: center;
}

.qr-modal.active {
  display: flex;
}

.qr-modal-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
}

.qr-modal-content {
  position: relative;
  background: #fff;
  border-radius: 16px;
  padding: 40px;
  text-align: center;
  max-width: 320px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.qr-modal-content img {
  width: 240px;
  height: 240px;
  border-radius: 8px;
}

.qr-modal-content p {
  margin-top: 16px;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}

.qr-modal-close {
  position: absolute;
  top: 12px;
  right: 16px;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--color-text-muted);
  cursor: pointer;
  line-height: 1;
}

.qr-modal-close:hover {
  color: var(--color-text);
}

/* ========== 动画 ========== */
[data-aos="fade-up"] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-aos="fade-up"].aos-animate {
  opacity: 1;
  transform: translateY(0);
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 3.6rem;
  }

  .work-card {
    flex-direction: column;
  }

  .work-card-image {
    width: 100%;
    min-height: 220px;
  }

  .writings-grid {
    grid-template-columns: 1fr;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 60px;
  }
}

@media (max-width: 768px) {
  .nav-links, .nav-cta {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .hero-title {
    font-size: 2.8rem;
  }

  .hero-subtitle {
    font-size: 1.05rem;
  }

  .overview-grid {
    grid-template-columns: 1fr;
  }

  .about-headline {
    font-size: 2rem;
  }

  .section-title {
    font-size: 1.6rem;
  }

  .collab-title {
    font-size: 1.8rem;
  }

  .footer-grid {
    flex-direction: column;
    gap: 32px;
  }

  .app-showcase {
    flex-direction: column;
    align-items: center;
  }

  .app-card {
    width: 100%;
    max-width: 280px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2.2rem;
  }

  .hero-greeting {
    font-size: 1.2rem;
  }

  .btn {
    padding: 10px 20px;
    font-size: 0.8rem;
  }

  .work-card-content {
    padding: 24px;
  }

  .project-highlight {
    padding: 28px;
  }

  .letter-card {
    padding: 24px;
  }
}