/* ============================================================
   史瑞祺 · 个人简历 | Lando Norris 风格深色主题
   ------------------------------------------------------------
   修改指南：
   - 想换主题色（现在是橙色）：改下面 :root 里的 --accent 和 --accent-soft
   - 想换背景深浅：改 --bg / --bg-2 / --panel
   - 想换字体：改 --display（大标题）和 --body（正文）
   - 页面结构在 index.html，文案在 js/main.js 的 I18N 对象里
   ============================================================ */

:root {
  /* 背景色系（由深到浅） */
  --bg: #0a0a0b;          /* 页面主背景 */
  --bg-2: #101013;        /* 交替区块（技能/经历区）背景 */
  --panel: #151519;       /* 卡片/浮层面板背景 */
  /* 文字颜色 */
  --text: #f4f4f2;        /* 主文字（近白） */
  --muted: #9aa0a6;       /* 次要文字（灰） */
  /* 线条与分隔 */
  --line: #26262c;        /* 边框 / 分隔线 */
  /* 主题色（品牌色）—— 全局唯一，改这里即可换整套配色 */
  --accent: #ff8000;      /* 橙色点缀：按钮、图标、高亮 */
  --accent-soft: rgba(255, 128, 0, 0.14); /* 主题色的半透明底（图标底板、标签底色） */
  /* 字体（Anton 英文标题 + 思源黑体中文；Space Grotesk 英文正文） */
  --display: "Anton", "Noto Sans SC", "Microsoft YaHei", "PingFang SC", sans-serif;
  --body: "Space Grotesk", "Noto Sans SC", "Microsoft YaHei", "PingFang SC", sans-serif;
  --header-h: 72px;       /* 顶部导航高度（改它会影响全站 section 的 scroll-margin） */
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--body);
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

::selection { background: var(--accent); color: #0a0a0b; }

/* 自定义滚动条 */
::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: #2c2c33; border-radius: 5px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }

img, svg { display: block; }

a { color: inherit; text-decoration: none; }

section { scroll-margin-top: var(--header-h); }

.accent { color: var(--accent); }

/* ============================================================
   背景动画层 — 柔光色块 + 尘埃粒子（不抢眼）
   ------------------------------------------------------------
   想调背景动画的强度/颜色/粒子密度：
   - 柔光色块：改下面 .orb-1/2/3 的透明度与 @keyframes orb-drift-* 的位移幅度
   - 尘埃粒子：逻辑在 js/main.js 的 initBgParticles（密度在 makeParticle/resize）
   ============================================================ */

/* ============================================================
   背景动画层 — Beams 扫射光束 + 氛围光 + 尘埃粒子
   ------------------------------------------------------------
   视觉：4 条斜向柔光光束在深色背景上缓慢扫过（舞台射灯感），
         中央一层极淡氛围光增强纵深，粒子细节叠加其上。
   想调背景动画：
   - 光束颜色/透明度：改 .beam-1~4 的 background（linear-gradient 里的 rgba）
   - 光束扫动速度/范围：改 @keyframes beam-sweep-* 的时长与 translate 值
   - 光束数量：增删 index.html 里 .beams 的 span（复制一个带新类名 + 加对应样式）
   - 尘埃粒子：逻辑在 js/main.js 的 initBgParticles（密度在 makeParticle/resize）
   ============================================================ */

.bg-anim,
.bg-canvas {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

.bg-canvas { opacity: 0.9; }

.bg-anim { overflow: hidden; }

/* 光束容器 */
.beams {
  position: absolute;
  inset: 0;
}

/* 单条光束：宽长条 + 渐变羽化 + 模糊 + 固定倾斜角，动画沿水平方向扫动 */
.beam {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 210vw;
  height: 16vw;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 128, 0, 0.13) 50%,
    transparent 100%
  );
  filter: blur(46px);
  transform: translate(-50%, -50%) rotate(-24deg);
  will-change: transform;
}

.beam-2 {
  height: 12vw;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(70, 150, 190, 0.10) 50%,
    transparent 100%
  );
  animation: beam-sweep-2 48s ease-in-out infinite alternate-reverse;
}

.beam-3 {
  height: 22vw;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 200, 150, 0.09) 50%,
    transparent 100%
  );
  animation: beam-sweep-3 56s ease-in-out infinite alternate;
}

.beam-4 {
  height: 9vw;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(150, 130, 255, 0.09) 50%,
    transparent 100%
  );
  animation: beam-sweep-4 38s ease-in-out infinite alternate-reverse;
}

.beam-1 { animation: beam-sweep-1 44s ease-in-out infinite alternate; }

/* 四条光束各自的扫动路径（角度固定，仅水平位移，形成“扫过”感） */
@keyframes beam-sweep-1 {
  from { transform: translate(-70vw, -50%) rotate(-24deg); }
  to { transform: translate(30vw, -50%) rotate(-24deg); }
}

@keyframes beam-sweep-2 {
  from { transform: translate(35vw, -50%) rotate(-32deg); }
  to { transform: translate(-65vw, -50%) rotate(-32deg); }
}

@keyframes beam-sweep-3 {
  from { transform: translate(-55vw, -50%) rotate(-18deg); }
  to { transform: translate(45vw, -50%) rotate(-18deg); }
}

@keyframes beam-sweep-4 {
  from { transform: translate(20vw, -50%) rotate(-40deg); }
  to { transform: translate(-80vw, -50%) rotate(-40deg); }
}

/* 中央氛围光：极淡的橙青色光晕，增强纵深，几乎不可察觉但让背景不单调 */
.aurora-glow {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 90vw;
  height: 90vw;
  transform: translate(-50%, -50%);
  background: radial-gradient(
    ellipse at center,
    rgba(255, 128, 0, 0.07) 0%,
    rgba(70, 150, 190, 0.05) 40%,
    transparent 70%
  );
  filter: blur(90px);
  animation: glow-breathe 12s ease-in-out infinite alternate;
}

@keyframes glow-breathe {
  from { opacity: 0.6; transform: translate(-50%, -50%) scale(1); }
  to { opacity: 1; transform: translate(-50%, -50%) scale(1.12); }
}

/* 内容层置于背景动画之上 */
main,
.site-footer {
  position: relative;
  z-index: 1;
}

/* ============================================================
   顶部导航
   顶部固定导航栏：改背景、模糊、导航链接样式
   ============================================================ */

.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--header-h);
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(20px, 4vw, 48px);
  transition: background 0.3s ease, border-color 0.3s ease, backdrop-filter 0.3s ease;
  border-bottom: 1px solid transparent;
}

.site-header.scrolled {
  background: rgba(10, 10, 11, 0.85);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
}

.brand {
  font-family: var(--display);
  font-size: 1.5rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.main-nav {
  display: flex;
  gap: clamp(18px, 3vw, 40px);
}

.main-nav a {
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--muted);
  position: relative;
  padding: 6px 0;
  transition: color 0.25s ease;
}

.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s ease;
}

.main-nav a:hover,
.main-nav a.active { color: var(--text); }

.main-nav a:hover::after,
.main-nav a.active::after { transform: scaleX(1); }

.header-actions { display: flex; align-items: center; gap: 14px; }

.lang-toggle {
  font-family: var(--body);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--text);
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 8px 16px;
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.25s ease;
}

.lang-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-1px);
}

.nav-burger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 8px;
}

.nav-burger span {
  width: 24px;
  height: 2px;
  background: var(--text);
  transition: transform 0.3s ease, opacity 0.3s ease;
}

/* ============================================================
   Hero
   首屏：左侧姓名+按钮，右侧照片 X 光组件（结构在 index.html 的 .hero-inner）
   ============================================================ */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: calc(var(--header-h) + 40px) clamp(20px, 6vw, 80px) 60px;
  overflow: hidden;
}

/* Hero 内部两栏布局 */
.hero-inner {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(32px, 5vw, 80px);
  align-items: center;
  max-width: 1400px;
  width: 100%;
  margin: 0 auto;
}

.hero-bg { position: absolute; inset: 0; pointer-events: none; }

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 84px 84px;
  -webkit-mask-image: radial-gradient(ellipse 80% 70% at 50% 40%, #000 30%, transparent 78%);
  mask-image: radial-gradient(ellipse 80% 70% at 50% 40%, #000 30%, transparent 78%);
}

.hero-glow {
  position: absolute;
  width: 56vw;
  height: 56vw;
  right: -12vw;
  top: -18vw;
  background: radial-gradient(circle, rgba(255, 128, 0, 0.20) 0%, transparent 60%);
  animation: glow-pulse 7s ease-in-out infinite;
}

@keyframes glow-pulse {
  0%, 100% { opacity: 0.75; }
  50% { opacity: 1; }
}

.hero-watermark {
  position: absolute;
  right: -0.04em;
  bottom: -0.18em;
  font-family: var(--display);
  font-size: clamp(14rem, 30vw, 30rem);
  line-height: 1;
  letter-spacing: 0.02em;
  color: transparent;
  -webkit-text-stroke: 1px rgba(255, 255, 255, 0.07);
  user-select: none;
}

.hero-content { position: relative; z-index: 2; }

/* ============================================================
   Hero 照片组件 — 常服/X光学士服双层 + 粒子
   ------------------------------------------------------------
   X 光交互的完整逻辑在 js/main.js 的 initPhotoXray：
   - 常服是底图（.photo-base），学士服是上层（.photo-xray）
   - 鼠标悬停时学士服以圆形 clip-path 从鼠标处“透视”出来
   - 圆形半径在 updateMask 里（固定 120px），粒子效果也在同一函数里
   ============================================================ */

.hero-photo {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: center;
  perspective: 1200px;   /* 3D 倾斜的透视距离，越大倾斜幅度越小 */
}

/* ============================================================
   工卡（ID Card）— 磨砂玻璃卡片 + 聚光灯 + 轻微倾斜
   ------------------------------------------------------------
   · .id-card 是卡壳：磨砂玻璃质感、圆角、信息条；鼠标移动时轻微 3D 倾斜
   · .id-spotlight 是聚光灯层：鼠标跟随的径向高光（JS 里更新坐标）
   · .photo-container 保留原 X 光交互（见下方对应注释）
   · 想调倾斜幅度：改 .id-card.is-tilting 的 rotateX/rotateY 上限（JS 里）
   ============================================================ */

.id-card {
  position: relative;
  width: clamp(280px, 30vw, 450px);
  padding: 14px;
  border-radius: 22px;
  background: linear-gradient(160deg, rgba(255, 255, 255, 0.10), rgba(255, 255, 255, 0.03));
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow:
    0 24px 60px -18px rgba(0, 0, 0, 0.7),
    inset 0 1px 0 rgba(255, 255, 255, 0.12);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  transform-style: preserve-3d;
  transform: rotateX(0deg) rotateY(0deg);
  transition: transform 0.18s ease-out, box-shadow 0.3s ease;
  will-change: transform;
}

.id-card.is-tilting {
  transition: transform 0.08s ease-out;
}

.id-card.is-hovering-card {
  box-shadow:
    0 30px 70px -18px rgba(255, 128, 0, 0.28),
    0 24px 60px -18px rgba(0, 0, 0, 0.7),
    inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

/* 聚光灯层：跟随鼠标的径向高光 */
.id-spotlight {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border-radius: 22px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.3s ease;
  background: radial-gradient(
    circle at var(--sx, 50%) var(--sy, 50%),
    rgba(255, 200, 120, 0.18) 0%,
    rgba(255, 128, 0, 0.06) 35%,
    transparent 65%
  );
  z-index: 3;
}

.id-card:hover .id-spotlight,
.id-card.is-tilting .id-spotlight { opacity: 1; }

/* 卡片内照片 X 光组件（沿用原尺寸，去掉原边框，融入卡壳） */
.id-card .photo-container {
  width: 100%;
  height: clamp(300px, 32vw, 480px);
  border-radius: 14px;
  overflow: hidden;
  border: none;
  background: var(--panel);
  cursor: none;
}

/* 卡片底部信息条 */
.id-card-info {
  padding: 14px 8px 6px;
  text-align: center;
}

.id-card-name {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 10px;
}

.id-name {
  font-family: var(--display);
  font-weight: 900;
  font-size: 1.35rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text);
}

.id-name-en {
  font-size: 0.72rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--muted);
}

.id-card-role {
  margin-top: 4px;
  font-size: 0.82rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.id-card-divider {
  width: 60px;
  height: 2px;
  margin: 12px auto 8px;
  background: var(--accent);
  border-radius: 2px;
  opacity: 0.8;
}

.id-card-id {
  font-size: 0.66rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.4);
}

.photo-container {
  position: relative;
  width: clamp(260px, 28vw, 420px);
  height: clamp(340px, 36vw, 540px);
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--line);
  cursor: none;
  background: var(--panel);
}

.photo-base,
.photo-xray {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 15%;
  pointer-events: none;
}

.photo-base { z-index: 1; }

.photo-xray {
  z-index: 2;
  opacity: 0;
  transition: opacity 0.15s ease;
}

.photo-container.is-hovering .photo-xray { opacity: 1; }

/* 遮罩层：只在鼠标周围圆形区域显示学士服 */
.photo-xray-mask {
  position: absolute;
  inset: 0;
  z-index: 3;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.photo-container.is-hovering .photo-xray-mask { opacity: 1; }

/* 圆环指示器 */
.photo-xray-ring {
  position: absolute;
  width: 140px;
  height: 140px;
  border: 2px solid var(--accent);
  border-radius: 50%;
  z-index: 5;
  pointer-events: none;
  opacity: 0;
  transform: translate(-50%, -50%) scale(0.6);
  transition: opacity 0.3s ease, transform 0.3s ease;
  box-shadow:
    0 0 20px rgba(255, 128, 0, 0.3),
    inset 0 0 20px rgba(255, 128, 0, 0.1);
}

.photo-container.is-hovering .photo-xray-ring {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
}

.photo-xray-ring::before {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px solid rgba(255, 128, 0, 0.4);
  border-radius: 50%;
}

.photo-xray-ring::after {
  content: "+";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--display);
  font-size: 1.5rem;
  color: var(--accent);
  text-shadow: 0 0 10px rgba(255, 128, 0, 0.6);
}

.photo-xray-label {
  position: absolute;
  bottom: 14px;
  left: 0;
  right: 0;
  z-index: 6;
  text-align: center;
  font-size: 0.7rem;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.45);
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.photo-container.is-hovering .photo-xray-label { opacity: 0; }

.particle-canvas {
  position: absolute;
  inset: 0;
  z-index: 4;
  pointer-events: none;
}

.hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.85rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 26px;
  border: 1px solid var(--line);
  padding: 8px 18px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.02);
}

.kicker-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 0 rgba(255, 128, 0, 0.6);
  animation: ping 2s infinite;
}

@keyframes ping {
  0% { box-shadow: 0 0 0 0 rgba(255, 128, 0, 0.55); }
  70% { box-shadow: 0 0 0 9px rgba(255, 128, 0, 0); }
  100% { box-shadow: 0 0 0 0 rgba(255, 128, 0, 0); }
}

.hero-name {
  font-family: var(--display);
  font-weight: 900;
  font-size: clamp(4.2rem, 15vw, 11rem);
  line-height: 1.02;
  letter-spacing: 0.01em;
  text-transform: uppercase;
  margin-bottom: 10px;
}

.hero-sub {
  font-size: clamp(1.05rem, 2.2vw, 1.5rem);
  font-weight: 500;
  color: var(--muted);
  max-width: 640px;
  margin-bottom: 40px;
}

.hero-cta { display: flex; flex-wrap: wrap; gap: 16px; margin-bottom: 56px; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 15px 34px;
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-radius: 4px;
  cursor: pointer;
  transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}

.btn svg { width: 18px; height: 18px; }

/* 邮箱地址保持原样小写显示，不被按钮的 uppercase 影响 */
#contactEmail span { text-transform: none; letter-spacing: 0; }

.btn-primary {
  background: var(--accent);
  color: #0a0a0b;
  border: 1px solid var(--accent);
  box-shadow: 0 0 0 0 rgba(255, 128, 0, 0.35);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 14px 34px -8px rgba(255, 128, 0, 0.5);
}

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

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: translateY(-3px);
}

.hero-next {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 0.8rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
}

.next-label { color: var(--muted); }

.next-value {
  color: var(--text);
  padding-left: 16px;
  border-left: 1px solid var(--line);
  font-weight: 500;
}

/* ============================================================
   跑马灯
   Hero 下方滚动字幕：改速度改 animation 时长，改内容在 index.html 的 .marquee
   ============================================================ */

.marquee {
  overflow: hidden;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--bg-2);
  padding: 16px 0;
}

.marquee-track {
  display: flex;
  width: max-content;
  animation: marquee 26s linear infinite;
}

.marquee-track span {
  font-family: var(--display);
  font-size: 1.15rem;
  letter-spacing: 0.14em;
  white-space: nowrap;
  color: var(--muted);
  padding-right: 4px;
}

@keyframes marquee {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

/* ============================================================
   通用区块
   各 section 的统一样式：标题、副标题、引言
   ============================================================ */

.section {
  padding: clamp(90px, 12vh, 150px) clamp(20px, 6vw, 80px);
  max-width: 1440px;
  margin: 0 auto;
}

.section-alt {
  background: rgba(16, 16, 19, 0.86);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  max-width: none;
}

.kicker {
  font-size: 0.85rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 18px;
}

.kicker-num {
  color: var(--muted);
}

.section-title {
  font-family: var(--display);
  font-weight: 900;
  font-size: clamp(2rem, 5vw, 3.4rem);
  line-height: 1.15;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  margin-bottom: 32px;
}

.lead {
  font-size: clamp(1.05rem, 1.6vw, 1.25rem);
  color: var(--muted);
  max-width: 780px;
  margin-bottom: 44px;
}

.about-quote {
  position: relative;
  max-width: 720px;
  padding: 28px 40px 28px 56px;
  border-left: 3px solid var(--accent);
  background: var(--panel);
  border-radius: 0 12px 12px 0;
}

.about-quote p {
  font-family: var(--display);
  font-weight: 900;
  font-size: clamp(1.2rem, 2.4vw, 1.7rem);
  line-height: 1.5;
}

.quote-mark {
  position: absolute;
  top: -14px;
  left: 18px;
  font-family: var(--display);
  font-size: 4rem;
  color: var(--accent);
  line-height: 1;
}

.about-quote cite {
  display: block;
  margin-top: 12px;
  font-style: normal;
  font-size: 0.9rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--muted);
}

/* ============================================================
   经历 · 时间线
   实习/教育时间线：改条目在 index.html 的 .timeline
   ============================================================ */

.timeline {
  position: relative;
  max-width: 860px;
  padding-left: 34px;
  border-left: 1px solid var(--line);
}

.timeline-item {
  position: relative;
  padding-bottom: 56px;
}

.timeline-item:last-child { padding-bottom: 0; }

.timeline-marker {
  position: absolute;
  left: -41px;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bg);
  border: 3px solid var(--accent);
  box-shadow: 0 0 0 5px var(--bg-2);
}

.timeline-date {
  font-size: 0.8rem;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 6px;
}

.timeline-title {
  font-family: var(--display);
  font-weight: 900;
  font-size: clamp(1.35rem, 2.6vw, 1.9rem);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: 4px;
}

.timeline-org {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 12px;
}

.timeline-desc {
  color: var(--muted);
  max-width: 640px;
}

/* ============================================================
   项目
   重点项目卡片 + 成果数据条 + 课程卡片
   ============================================================ */

.project-tag {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid rgba(255, 128, 0, 0.35);
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 18px;
}

.project-featured {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(32px, 5vw, 64px);
  align-items: center;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: clamp(28px, 4vw, 52px);
  margin-bottom: 72px;
  transition: border-color 0.3s ease;
}

.project-featured:hover { border-color: rgba(255, 128, 0, 0.5); }

.project-title {
  font-family: var(--display);
  font-weight: 900;
  font-size: clamp(1.3rem, 2.6vw, 2rem);
  line-height: 1.35;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  margin-bottom: 16px;
}

.project-desc {
  color: var(--muted);
  margin-bottom: 26px;
  max-width: 600px;
}

/* 成果数据条（毕业论文核心指标） */
.project-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 18px;
  margin-bottom: 26px;
  padding: 20px 22px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-2);
}

.stat { text-align: left; }

.stat-num {
  display: block;
  font-family: var(--display);
  font-weight: 900;
  font-size: clamp(1.5rem, 2.6vw, 2.1rem);
  line-height: 1.1;
  color: var(--accent);
  letter-spacing: 0.02em;
}

.stat-label {
  display: block;
  margin-top: 4px;
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.chips { display: flex; flex-wrap: wrap; gap: 10px; }

.chip {
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--text);
  background: var(--bg-2);
  border: 1px solid var(--line);
  padding: 7px 14px;
  border-radius: 999px;
  transition: border-color 0.25s ease, color 0.25s ease;
}

.chip:hover { border-color: var(--accent); color: var(--accent); }

.chip-sm { font-size: 0.72rem; padding: 5px 11px; }

/* 重点项目右侧：雷达可视化（呼应 GEE 海冰检测） */
.project-visual {
  position: relative;
  aspect-ratio: 1;
  border-radius: 12px;
  overflow: hidden;
  background: radial-gradient(circle at 50% 50%, #0d1117 0%, #08090c 70%);
  border: 1px solid var(--line);
  min-height: 280px;
}

.map-grid {
  position: absolute;
  inset: 0;
  opacity: 0.5;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.06) 1px, transparent 1px);
  background-size: 36px 36px;
}

.radar {
  position: absolute;
  inset: 18%;
  border-radius: 50%;
}

.radar-ring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 1px solid rgba(255, 128, 0, 0.35);
}

.radar-ring.r2 { inset: 22%; }
.radar-ring.r3 { inset: 44%; }

.radar-sweep {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: conic-gradient(from 0deg, rgba(255, 128, 0, 0.5) 0deg, transparent 70deg);
  animation: sweep 4.5s linear infinite;
}

@keyframes sweep {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.radar-dot {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 10px;
  height: 10px;
  margin: -5px 0 0 -5px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 5px rgba(255, 128, 0, 0.25), 0 0 24px rgba(255, 128, 0, 0.8);
  animation: dot-pulse 2.4s ease-in-out infinite;
}

@keyframes dot-pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.35); }
}

.visual-label {
  position: absolute;
  left: 14px;
  bottom: 12px;
  font-size: 0.72rem;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.55);
}

.course-head { margin-bottom: 26px; }
.course-sub { color: var(--muted); }

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 18px;
}

.course-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 26px 24px;
  transition: transform 0.3s ease, border-color 0.3s ease, background 0.3s ease;
}

.course-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent);
  background: #1a1a1f;
}

/* 课程卡片顶部配图（SVG 插画，橙色线条风格） */
.course-icon {
  width: 52px;
  height: 52px;
  color: var(--accent);
  padding: 10px;
  background: var(--accent-soft);
  border: 1px solid rgba(255, 128, 0, 0.28);
  border-radius: 12px;
  margin-bottom: 18px;
  transition: transform 0.3s ease, background 0.3s ease, box-shadow 0.3s ease;
}

.course-card:hover .course-icon {
  transform: translateY(-3px) scale(1.05);
  background: rgba(255, 128, 0, 0.22);
  box-shadow: 0 8px 20px -6px rgba(255, 128, 0, 0.4);
}

.course-title {
  font-family: var(--display);
  font-weight: 900;
  font-size: 1.15rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 14px;
}

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

/* ============================================================
   技能
   三张技能卡：图标/标题/标签
   ============================================================ */

.skill-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 22px;
}

.skill-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 34px 30px;
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.skill-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent);
}

.skill-icon {
  width: 44px;
  height: 44px;
  color: var(--accent);
  margin-bottom: 22px;
}

.skill-title {
  font-family: var(--display);
  font-weight: 900;
  font-size: 1.3rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 10px;
}

.skill-desc {
  color: var(--muted);
  font-size: 0.95rem;
  margin-bottom: 18px;
}

/* ============================================================
   联系
   联系方式区：邮箱、GitHub 按钮（链接在 index.html）
   ============================================================ */

.contact {
  text-align: center;
  max-width: 900px;
}

.contact .kicker { justify-content: center; }

.contact-title { margin-bottom: 16px; }

.contact-sub {
  color: var(--muted);
  max-width: 560px;
  margin: 0 auto 44px;
}

.contact-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
  margin-bottom: 24px;
}

.contact-note {
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  color: var(--muted);
}

/* ============================================================
   页脚
   底部版权与回顶链接
   ============================================================ */

.site-footer {
  border-top: 1px solid var(--line);
  padding: 40px clamp(20px, 6vw, 80px);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.footer-brand {
  font-family: var(--display);
  font-size: 1.2rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.footer-copy { font-size: 0.85rem; color: var(--muted); }

.footer-top {
  font-size: 0.82rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
  transition: color 0.25s ease;
}

.footer-top:hover { color: var(--accent); }

/* ============================================================
   滚动入场动效
   元素进入视口的渐显动画。想整体关闭在 @media prefers-reduced-motion
   ============================================================ */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

.course-grid .reveal:nth-child(2) { transition-delay: 0.06s; }
.course-grid .reveal:nth-child(3) { transition-delay: 0.12s; }
.course-grid .reveal:nth-child(4) { transition-delay: 0.18s; }
.course-grid .reveal:nth-child(5) { transition-delay: 0.06s; }
.course-grid .reveal:nth-child(6) { transition-delay: 0.12s; }
.course-grid .reveal:nth-child(7) { transition-delay: 0.18s; }
.course-grid .reveal:nth-child(8) { transition-delay: 0.24s; }

.skill-grid .reveal:nth-child(2) { transition-delay: 0.1s; }
.skill-grid .reveal:nth-child(3) { transition-delay: 0.2s; }

/* ============================================================
   自定义光标 — 橙色点 + 跟随环 + 拖尾粒子
   ------------------------------------------------------------
   · .cursor-dot 橙色小点：紧贴鼠标，始终在鼠标位置
   · .cursor-ring 圆环：延迟跟随鼠标（平滑插值），悬停可交互元素时放大
   · .cursor-trail 画布：鼠标移动时喷射橙色微光粒子（淡拖尾）
   · 逻辑在 js/main.js 的 initCustomCursor
   · 想调整：拖尾强度/颜色改 .cursor-trail 与 JS 里的 fillStyle/速度
   · 想完全关闭：删掉这三处样式 + HTML 里的三个元素，并恢复 cursor 默认
   ============================================================ */

/* 全局隐藏系统光标（桌面端），改用自定义光标 */
@media (hover: hover) and (pointer: fine) {
  body,
  body a,
  body button,
  body .photo-container,
  body .id-card {
    cursor: none;
  }

  /* 橙色小点：紧贴鼠标 */
  .cursor-dot {
    position: fixed;
    left: 0;
    top: 0;
    width: 8px;
    height: 8px;
    margin: -4px 0 0 -4px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 8px rgba(255, 128, 0, 0.6);
    pointer-events: none;
    z-index: 9999;
    transform: translate3d(0, 0, 0);
    will-change: transform;
  }

  /* 跟随圆环：延迟跟随，平滑插值由 JS 驱动 */
  .cursor-ring {
    position: fixed;
    left: 0;
    top: 0;
    width: 36px;
    height: 36px;
    margin: -18px 0 0 -18px;
    border-radius: 50%;
    border: 1.5px solid rgba(255, 128, 0, 0.65);
    pointer-events: none;
    z-index: 9998;
    transform: translate3d(0, 0, 0);
    will-change: transform;
    transition: width 0.25s ease, height 0.25s ease, margin 0.25s ease,
                border-color 0.25s ease, background 0.25s ease;
  }

  /* 悬停可交互元素时圆环放大（按钮/链接/卡片/照片） */
  .cursor-ring.is-active {
    width: 60px;
    height: 60px;
    margin: -30px 0 0 -30px;
    border-color: rgba(255, 128, 0, 0.9);
    background: rgba(255, 128, 0, 0.10);
  }

  /* 拖尾粒子画布：全屏，指针不响应 */
  .cursor-trail {
    position: fixed;
    inset: 0;
    z-index: 9997;
    pointer-events: none;
  }
}

/* ============================================================
   响应式
   移动端适配：960px 和 760px 两档断点
   ============================================================ */

@media (max-width: 960px) {
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-content { order: 1; }
  .hero-photo { order: 2; }

  .photo-container {
    width: clamp(220px, 50vw, 320px);
    height: clamp(280px, 65vw, 420px);
  }

  .project-featured {
    grid-template-columns: 1fr;
  }

  .project-visual { min-height: 320px; }
}

@media (max-width: 760px) {
  :root { --header-h: 62px; }

  .nav-burger { display: flex; }

  .main-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(10, 10, 11, 0.97);
    -webkit-backdrop-filter: blur(14px);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--line);
    padding: 8px 24px 18px;
    transform: translateY(-120%);
    transition: transform 0.35s ease;
  }

  .site-header.nav-open .main-nav { transform: translateY(0); }

  .photo-container {
    width: clamp(180px, 55vw, 260px);
    height: clamp(230px, 70vw, 340px);
  }

  .main-nav a {
    padding: 14px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  }

  .main-nav a::after { display: none; }

  .site-header.nav-open .nav-burger span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .site-header.nav-open .nav-burger span:nth-child(2) { opacity: 0; }
  .site-header.nav-open .nav-burger span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  .hero { padding-top: calc(var(--header-h) + 60px); }

  .hero-cta .btn { width: 100%; justify-content: center; }

  .timeline { padding-left: 26px; }
  .timeline-marker { left: -33px; }

  .hero-watermark { font-size: 11rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .marquee-track,
  .radar-sweep,
  .hero-glow,
  .kicker-dot,
  .radar-dot,
  .beam,
  .aurora-glow,
  .bg-canvas { animation: none; }
  .reveal { opacity: 1; transform: none; transition: none; }
}