/* ============================================================
   全站样式表
   ------------------------------------------------------------
   这是整个网站的"外观"定义。想改颜色、圆角、字体大小,先从
   下面的"设计变量"改起。每个区块都有中文注释说明它对应页面上
   的哪个部分。
   ============================================================ */

/* ---------- ① 设计变量:全站的配色和尺寸都集中在这里 ---------- */
:root {
  /* 颜色(苹果官网风格的灰黑配色) */
  --color-black: #000000;          /* 标题、按钮、分隔线 */
  --color-text: #1D1D1F;           /* 正文深色文字 */
  --color-grey: #86868B;           /* 次要说明文字(苹果灰) */
  --color-light: #F5F5F7;          /* 浅灰背景(标签、卡片底) */
  --color-blue: #0071E3;           /* 链接蓝色 */
  --color-white: #FFFFFF;

  /* 圆角 */
  --radius-pill: 9999px;           /* 药丸形(按钮、标签) */
  --radius-card: 12px;             /* 卡片圆角 */

  /* 阴影(鼠标悬停卡片时出现) */
  --shadow-card: 0 12px 40px rgba(0, 0, 0, 0.08);

  /* 内容最大宽度:正文居中栏的宽度上限 */
  --content-max: 1200px;
}

/* ---------- ② 全局基础 ---------- */
* { margin: 0; padding: 0; box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  font-family: ui-sans-serif, system-ui, sans-serif,
    "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
  line-height: 1.5;
  color: var(--color-black);
  background: var(--color-white);
}

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

/* 整个页面是一个纵向弹性布局:页头 / 主体 / 页脚 */
.site {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
.site-main { flex: 1; }

/* 通用图标样式(所有内联 SVG 图标) */
.icon {
  stroke: currentColor;
  fill: currentColor;
  stroke-width: 0;
  flex-shrink: 0;
}

/* ============================================================
   ③ 顶部导航栏(每页都有,由 js/main.js 自动生成)
   ============================================================ */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  /* 毛玻璃效果:半透明白 + 背景模糊 */
  background: rgba(255, 255, 255, 0.72);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  backdrop-filter: blur(20px) saturate(180%);
}
.header-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 24px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
/* 左上角 Logo(姓名) */
.logo {
  font-size: 16px;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--color-black);
  text-decoration: none;
  transition: opacity 0.2s;
}
.logo:hover { opacity: 0.7; }

/* 桌面端菜单:一排链接。手机宽度下隐藏 */
.header-nav {
  display: none;
  align-items: center;
  gap: 32px;
}
@media (min-width: 768px) { .header-nav { display: flex; } }

.nav-link {
  font-size: 14px;
  line-height: 20px;
  font-weight: 500;
  color: var(--color-grey);
  text-decoration: none;
  transition: color 0.2s;
}
.nav-link:hover { color: var(--color-black); }
/* 当前页面所在的菜单项:黑色高亮 */
.nav-link.active { color: var(--color-black); }

/* 手机端汉堡按钮:只在窄屏显示 */
.menu-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px; height: 40px;
  border: none; background: none;
  cursor: pointer;
  color: var(--color-black);
  transition: transform 0.1s;
}
.menu-btn:active { transform: scale(0.95); }
@media (min-width: 768px) { .menu-btn { display: none; } }

/* 手机端全屏菜单:黑底白字大菜单 */
.mobile-menu {
  position: fixed;
  inset: 0;
  top: 56px;
  z-index: 40;
  background: var(--color-black);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 32px;
}
.mobile-menu[hidden] { display: none; }
.mobile-menu a {
  font-size: 24px;
  line-height: 32px;
  font-weight: 600;
  color: var(--color-white);
  text-decoration: none;
  transition: color 0.2s;
}
.mobile-menu a:hover { color: var(--color-grey); }

/* ============================================================
   ④ 页脚(每页都有,由 js/main.js 自动生成)
   ============================================================ */
.footer {
  background: var(--color-black);
  color: var(--color-white);
  padding: 64px 0;
}
.footer-inner { max-width: var(--content-max); margin: 0 auto; padding: 0 24px; }
.footer-top {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
}
@media (min-width: 768px) {
  .footer-top { flex-direction: row; align-items: center; }
}
.footer-name {
  font-size: 20px;
  line-height: 28px;
  font-weight: 600;
  letter-spacing: -0.02em;
}
.footer-tagline { font-size: 14px; line-height: 20px; color: var(--color-grey); margin-top: 8px; }
.footer-nav { display: flex; flex-wrap: wrap; gap: 24px; }
.footer-link {
  font-size: 14px;
  line-height: 20px;
  color: var(--color-grey);
  text-decoration: none;
  transition: color 0.2s;
}
.footer-link:hover { color: var(--color-white); }
.footer-bottom {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}
.footer-copy { font-size: 12px; line-height: 16px; color: var(--color-grey); }

/* ============================================================
   ⑤ 滚动渐入动画(配合 js/main.js 里的 IntersectionObserver)
   ------------------------------------------------------------
   所有带 .reveal 类的元素,刚加载时是"隐藏状态"(透明 + 下移 40px),
   滚动到视口内 20% 时被加上 .visible,在 0.5 秒内淡入上移。
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.5s ease-out, transform 0.5s ease-out;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
/* 延迟类:让相邻元素依次出现,形成阶梯感(单位:毫秒) */
.reveal-delay-100 { transition-delay: 100ms; }
.reveal-delay-150 { transition-delay: 150ms; }
.reveal-delay-200 { transition-delay: 200ms; }
.reveal-delay-300 { transition-delay: 300ms; }

/* ============================================================
   ⑥ 通用小块:按钮 / 分隔线 / 区块标题
   ============================================================ */
/* 黑色药丸按钮(如 "View My Work") */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-black);
  color: var(--color-white);
  text-decoration: none;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-pill);
  font-weight: 500;
  transition: background 0.3s, transform 0.3s;
}
.btn:hover { background: var(--color-text); }
.btn:active { transform: scale(0.97); }
/* 小号按钮:首页首屏 / 各页底部 CTA */
.btn-sm { font-size: 14px; line-height: 20px; padding: 14px 32px; }
/* 大号按钮:首页联系区 / 联系页 */
.btn-lg { font-size: 16px; padding: 16px 32px; gap: 12px; }

/* 2px 黑色分隔线(区块之间) */
.divider { width: 100%; height: 2px; background: var(--color-black); }
/* 分隔线外面套的容器(让线和内容同宽) */
.divider-wrap { max-width: var(--content-max); margin: 0 auto; padding: 0 24px; }

/* 内容区通用容器 */
.container {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 24px;
}

/* 大标题(H1:各页标题)。行高用浏览器默认 1.5,与原站一致 */
.page-title {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-black);
}
@media (min-width: 768px) { .page-title { font-size: 48px; } }

/* 二级标题(H2:各区块标题)。24px 字对应原站 32px 行高 */
.section-h2 {
  font-size: 24px;
  line-height: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-black);
}

/* 标题 + 图标并排的小标题行 */
.h2-row { display: flex; align-items: center; gap: 12px; }

/* 灰色说明文字(首页各区块的介绍,对应原站 text-lg 的 28px 行高) */
.desc { color: var(--color-grey); line-height: 28px; }

/* 蓝色文字链接(如 "Learn more") */
.link-blue {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-blue);
  text-decoration: none;
}
.link-blue:hover { text-decoration: underline; }

/* 页面底部居中的大按钮容器 */
.page-cta { text-align: center; margin-top: 64px; }

/* 子页面顶部"返回"链接 */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  line-height: 20px;
  color: var(--color-grey);
  text-decoration: none;
  transition: color 0.2s;
}
.back-link:hover { color: var(--color-black); }

/* ============================================================
   ⑦ 首页( index.html )
   ============================================================ */
/* 首屏:全屏高,白→浅灰渐变,内容居中 */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(to bottom, #ffffff, var(--color-light));
}
.hero-inner { max-width: var(--content-max); margin: 0 auto; padding: 0 24px; text-align: center; }
.hero-title {
  font-size: 40px;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.05;
  color: var(--color-black);
}
@media (min-width: 768px) { .hero-title { font-size: 72px; } }
.hero-sub {
  margin-top: 24px;
  font-size: 18px;
  color: var(--color-grey);
  max-width: 512px;
  margin-left: auto; margin-right: auto;
  line-height: 1.625;
}
@media (min-width: 768px) { .hero-sub { font-size: 20px; } }
.hero-cta { margin-top: 40px; }

/* 首页主体:各区块纵向排列,相邻间隔 64px(桌面 96px) */
.home-sections {
  display: flex;
  flex-direction: column;
  gap: 64px;
  padding: 64px 0;
}
@media (min-width: 768px) {
  .home-sections { gap: 96px; padding: 96px 0; }
}

/* 首页的大区块标题(比子页面标题更大) */
.home-h2 {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-black);
}
@media (min-width: 768px) { .home-h2 { font-size: 48px; } }

/* 首页 Education 区块:左文字 + 右卡片 */
.edu-row {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
}
@media (min-width: 768px) { .edu-row { flex-direction: row; } }
.edu-text .desc { margin-top: 16px; font-size: 18px; max-width: 448px; }
/* 右侧"高中文凭"卡片 */
.edu-card {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 24px;
  border: 1px solid rgba(0, 0, 0, 0.1);
  border-radius: var(--radius-card);
  text-decoration: none;
  transition: box-shadow 0.3s, transform 0.3s;
}
.edu-card:hover { box-shadow: var(--shadow-card); transform: translateY(-4px); }
.edu-card-text { text-align: right; }
.edu-card-title { font-size: 14px; line-height: 20px; font-weight: 600; color: var(--color-black); }
.edu-card-sub { font-size: 12px; line-height: 16px; color: var(--color-grey); margin-top: 4px; }
/* 卡片右侧的箭头图标:悬停变黑并右移 */
.edu-card .icon {
  color: var(--color-grey);
  transition: color 0.2s, transform 0.2s;
}
.edu-card:hover .icon { color: var(--color-black); transform: translateX(4px); }

/* 圆角浅灰小标签(如技能标签) */
.tags { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.tag {
  padding: 10px 20px;
  background: var(--color-light);
  font-size: 14px;
  line-height: 20px;
  font-weight: 500;
  color: var(--color-text);
  border-radius: var(--radius-pill);
}

/* 项目卡片网格(首页 3 列,项目页 2 列) */
.projects-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  margin-top: 40px;
}
@media (min-width: 768px) {
  .home-projects-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 1024px) {
  .home-projects-grid { grid-template-columns: repeat(3, 1fr); }
}

/* 卡片本体 */
.card {
  display: block;
  border-radius: var(--radius-card);
  overflow: hidden;
  border: 1px solid rgba(0, 0, 0, 0.05);
  text-decoration: none;
  transition: box-shadow 0.3s, transform 0.3s;
}
.card:hover { box-shadow: var(--shadow-card); transform: translateY(-4px); }
.card-img-wrap { aspect-ratio: 3 / 2; overflow: hidden; }
.card-img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform 0.5s;
}
.card:hover .card-img { transform: scale(1.03); }
.card-body { padding: 20px; }
.card-title { font-size: 16px; font-weight: 600; color: var(--color-black); }
.card-desc {
  margin-top: 8px;
  font-size: 14px;
  color: var(--color-grey);
  line-height: 1.625;
  /* 最多显示两行,超出部分省略 */
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* 首页 Interests 区块的 3 个浅灰卡片 */
.interests-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  margin-top: 32px;
}
@media (min-width: 768px) { .interests-grid { grid-template-columns: repeat(3, 1fr); } }
.interest-card { padding: 24px; background: var(--color-light); border-radius: var(--radius-card); }
.interest-card .card-desc { display: block; -webkit-line-clamp: unset; overflow: visible; }

/* 首页联系区 */
.contact-section { text-align: center; }
.contact-section .desc { margin-top: 16px; font-size: 18px; }
.contact-section .btn { margin-top: 32px; }

/* ============================================================
   ⑧ 子页面通用布局(除首页外的所有页面)
   ============================================================ */
/* 页面顶部留出 56px 给固定导航栏 */
.page { padding-top: 56px; min-height: 100vh; }
.page-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 64px 24px;
}
@media (min-width: 768px) { .page-inner { padding: 96px 24px; } }
.page-title { margin-top: 32px; }
.page-sub { margin-top: 16px; font-size: 18px; line-height: 28px; color: var(--color-grey); max-width: 512px; }
/* 分隔线上下各 64px */
.page-divider { margin: 64px 0; }

/* ---------- Education 页:时间线 ---------- */
.timeline { margin-top: 64px; }
.timeline-item {
  position: relative;
  padding-left: 32px;
  padding-bottom: 48px;
  border-left: 2px solid rgba(0, 0, 0, 0.1);
}
.timeline-item:last-child { border-left: 0; padding-bottom: 0; }
.timeline-dot {
  position: absolute;
  left: -5px;
  top: 4px;
  width: 8px; height: 8px;
  border-radius: var(--radius-pill);
  background: var(--color-black);
}
.timeline-period {
  font-size: 12px;
  line-height: 16px;
  font-weight: 500;
  color: var(--color-grey);
  text-transform: uppercase;
  letter-spacing: 0.025em;
}
.timeline-school { margin-top: 8px; font-size: 20px; line-height: 28px; font-weight: 600; color: var(--color-black); }
.timeline-detail { font-size: 14px; line-height: 20px; font-weight: 500; color: var(--color-blue); margin-top: 4px; }
.timeline-desc { margin-top: 12px; color: var(--color-grey); line-height: 1.625; max-width: 512px; }

/* Education 页:奖项网格 */
.awards-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 32px;
}
@media (min-width: 768px) { .awards-grid { grid-template-columns: repeat(2, 1fr); } }
.award-item {
  padding: 16px 20px;
  background: var(--color-light);
  border-radius: var(--radius-card);
  font-size: 14px;
  line-height: 20px;
  font-weight: 500;
  color: var(--color-text);
}

/* Education 页:课程标签(带边框的圆标签) */
.courses { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.course-pill {
  padding: 8px 16px;
  border: 1px solid rgba(0, 0, 0, 0.1);
  border-radius: var(--radius-pill);
  font-size: 14px;
  line-height: 20px;
  color: var(--color-text);
}

/* ---------- Skills 页 ---------- */
.skill-groups { margin-top: 64px; display: flex; flex-direction: column; gap: 64px; }
.skill-group-head { display: flex; align-items: center; gap: 12px; margin-bottom: 32px; }
.skill-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}
@media (min-width: 768px) { .skill-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .skill-grid { grid-template-columns: repeat(3, 1fr); } }
.skill-card {
  padding: 24px;
  border: 1px solid rgba(0, 0, 0, 0.05);
  border-radius: var(--radius-card);
  transition: box-shadow 0.3s, transform 0.3s;
}
.skill-card:hover { box-shadow: var(--shadow-card); transform: translateY(-4px); }
.skill-top { display: flex; align-items: center; justify-content: space-between; }
.skill-name { font-size: 16px; font-weight: 600; color: var(--color-black); }
.skill-level { font-size: 12px; line-height: 16px; font-weight: 500; color: var(--color-grey); }
/* 进度条:浅灰底 + 黑色填充(宽度写在 HTML 的 style 里,如 style="width:90%") */
.skill-bar {
  margin-top: 12px;
  height: 6px;
  background: var(--color-light);
  border-radius: var(--radius-pill);
  overflow: hidden;
}
.skill-bar-fill {
  height: 100%;
  background: var(--color-black);
  border-radius: var(--radius-pill);
  transition: width 0.7s;
}
.skill-desc { margin-top: 16px; font-size: 14px; color: var(--color-grey); line-height: 1.625; }

/* ---------- Projects 页 ---------- */
.projects-page-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  margin-top: 48px;
}
@media (min-width: 768px) { .projects-page-grid { grid-template-columns: repeat(2, 1fr); } }
.project-card .card-body { padding: 24px; }
.card-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 12px; }
.card-tag {
  padding: 4px 12px;
  background: var(--color-light);
  font-size: 12px;
  line-height: 16px;
  font-weight: 500;
  color: var(--color-grey);
  border-radius: var(--radius-pill);
}
.project-card-title {
  font-size: 18px;
  line-height: 28px;
  font-weight: 600;
  color: var(--color-black);
  transition: color 0.2s;
}
.project-card:hover .project-card-title { color: var(--color-blue); }
.project-card-desc { margin-top: 8px; font-size: 14px; color: var(--color-grey); line-height: 1.625; }
.view-details {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  font-size: 14px;
  line-height: 20px;
  font-weight: 500;
  color: var(--color-black);
}

/* ---------- Interests 页 ---------- */
.interest-rows { margin-top: 64px; display: flex; flex-direction: column; gap: 48px; }
.interest-row {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 32px;
}
/* 偶数行图片放右边(手机端始终上图下文) */
@media (min-width: 768px) {
  .interest-row { flex-direction: row; }
  .interest-row.reverse { flex-direction: row-reverse; }
  .interest-img, .interest-text { width: 50%; }
}
.interest-img { border-radius: var(--radius-card); overflow: hidden; width: 100%; }
.interest-img img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  transition: transform 0.5s;
}
.interest-img img:hover { transform: scale(1.02); }
.interest-text { width: 100%; }
.interest-name { font-size: 20px; line-height: 28px; font-weight: 700; letter-spacing: -0.02em; color: var(--color-black); }
.interest-desc { margin-top: 16px; color: var(--color-grey); line-height: 1.625; }
/* 每行兴趣之间加一条黑色分隔线(最后一行没有) */
.interest-divider { width: 100%; height: 2px; background: var(--color-black); margin-top: 48px; }

/* ---------- Contact 页 ---------- */
.contact-page { padding-top: 56px; min-height: 100vh; display: flex; align-items: center; }
.contact-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 64px 24px;
  width: 100%;
}
@media (min-width: 768px) { .contact-inner { padding: 96px 24px; } }
.contact-box { margin-top: 64px; text-align: center; max-width: 512px; margin-left: auto; margin-right: auto; }
.contact-desc { margin-top: 24px; font-size: 18px; color: var(--color-grey); line-height: 1.625; }
.contact-box .btn { margin-top: 40px; }

/* ---------- 项目详情页 ---------- */
.detail-tags { margin-top: 32px; display: flex; flex-wrap: wrap; gap: 8px; }
.detail-desc { margin-top: 16px; font-size: 18px; color: var(--color-grey); max-width: 672px; line-height: 1.625; }
.detail-hero { margin-top: 48px; border-radius: var(--radius-card); overflow: hidden; }
.detail-hero img { width: 100%; aspect-ratio: 2 / 1; object-fit: cover; }
.detail-meta {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  margin-top: 48px;
}
@media (min-width: 768px) { .detail-meta { grid-template-columns: repeat(2, 1fr); } }
.detail-meta-card { padding: 24px; background: var(--color-light); border-radius: var(--radius-card); }
.detail-meta-label {
  font-size: 14px;
  line-height: 20px;
  font-weight: 600;
  color: var(--color-grey);
  text-transform: uppercase;
  letter-spacing: 0.025em;
}
.detail-meta-value { margin-top: 8px; font-size: 16px; font-weight: 500; color: var(--color-black); }
.outcomes { margin-top: 32px; display: flex; flex-direction: column; gap: 16px; }
.outcome-item { display: flex; align-items: flex-start; gap: 16px; }
/* 黑色圆点里的数字序号 */
.outcome-num {
  flex-shrink: 0;
  width: 24px; height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-black);
  color: var(--color-white);
  font-size: 12px;
  font-weight: 700;
  border-radius: var(--radius-pill);
}
.outcome-text { color: var(--color-text); line-height: 1.625; }