/* ============================================================
   1. CSS VARIABLES — 主题设计令牌
   ============================================================ */
:root {
  /* 主题色 — 高原山野灰蓝系 */
  --accent: #94a8b8;
  --accent-hover: #e8b0a0;
  --accent-dim: rgba(148, 168, 184, 0.08);
  --accent-glow: rgba(148, 168, 184, 0.25);

  /* 背景色 */
  --bg-primary: #0d1117;
  --bg-card: rgba(30, 38, 48, 0.65);
  --bg-card-featured: rgba(35, 42, 50, 0.72);
  --bg-panel: rgba(20, 26, 34, 0.6);
  --bg-nav: rgba(13, 17, 23, 0.82);
  --bg-nav-scrolled: rgba(13, 17, 23, 0.94);

  /* 文字色 */
  --text-primary: #e6ebf0;
  --text-heading: #ffffff;
  --text-muted: #a1b2c2;
  --text-dim: #a1b2c2;
  --text-subtitle: #a1b2c2;

  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 14px;
  --radius-xl: 16px;
  --radius-pill: 30px;

  /* 间距 */
  --space-xs: 6px;
  --space-sm: 12px;
  --space-md: 24px;
  --space-lg: 40px;
  --space-xl: 60px;
  --space-2xl: 100px;

  /* 边框 */
  --border-subtle: rgba(148, 168, 184, 0.1);
  --border-medium: rgba(148, 168, 184, 0.2);
  --border-glow: rgba(232, 176, 160, 0.25);

  /* 过渡 */
  --ease-out-expo: cubic-bezier(0.25, 0.46, 0.45, 0.94);
  --transition-card: all 0.4s var(--ease-out-expo);
  --transition-fast: all 0.3s ease;
}

/* 亮色主题覆盖 */
[data-theme="light"] {
  --bg-primary: #e8ecf1;
  --bg-card: rgba(255,255,255,0.72);
  --bg-card-featured: rgba(255,250,248,0.78);
  --bg-panel: rgba(255,255,255,0.7);
  --bg-nav: rgba(232,236,241,0.88);
  --bg-nav-scrolled: rgba(232,236,241,0.96);
  --text-primary: #2c3e50;
  --text-heading: #1a1a2e;
  --text-muted: #5a6c7d;
  --text-dim: #4a5568;
  --text-subtitle: #5a6c7d;
  --accent: #6b7d8e;
  --accent-dim: rgba(107,125,142,0.08);
  --accent-glow: rgba(107,125,142,0.2);
  --border-subtle: rgba(107,125,142,0.12);
  --border-medium: rgba(107,125,142,0.2);
  --border-glow: rgba(232,176,160,0.2);
}

/* ============================================================
   2. RESET & BASE
   ============================================================ */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:80px}
body{
  font-family:"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
  background:var(--bg-primary);color:var(--text-primary);
  line-height:1.7;overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
  transition:color 0.4s ease;
}
/* 噪点纹理保留在 ::before (已在 section 21 定义) */

/* 背景层 — 滚动联动模糊+遮罩 */
.bg-layer{
  position:fixed;top:0;left:0;width:100%;height:100vh;
  z-index:-2;pointer-events:none;
  background:url('/static/img/bg.jpg') center/cover no-repeat;
  will-change:filter;
}
.bg-overlay{
  position:fixed;top:0;left:0;width:100%;height:100vh;
  z-index:-1;pointer-events:none;
  background:rgba(0,0,0,0.4);
  will-change:opacity;
}

a{text-decoration:none;color:inherit}
ul{list-style:none}
img{display:block;max-width:100%}

/* 自定义滚动条 */
::-webkit-scrollbar{width:6px}
::-webkit-scrollbar-track{background:var(--bg-primary)}
::-webkit-scrollbar-thumb{background:var(--accent);border-radius:3px}

/* ============================================================
   3. A11Y — 焦点 & 键盘导航
   ============================================================ */
:focus-visible{
  outline:2px solid var(--accent);
  outline-offset:2px;
  border-radius:var(--radius-sm);
}
.skip-link{
  position:absolute;top:-100px;left:20px;z-index:9999;
  background:var(--accent);color:var(--bg-primary);padding:8px 16px;
  border-radius:var(--radius-sm);font-weight:700;
  transition:top 0.3s;
}
.skip-link:focus{top:10px}

/* ============================================================
   4. LAYOUT — 容器 & 通用类
   ============================================================ */
.container{max-width:1200px;margin:0 auto;padding:0 var(--space-lg)}
.section-title{
  font-size:2rem;font-weight:700;color:var(--text-heading);
  text-align:center;margin-bottom:var(--space-sm);letter-spacing:2px
}
.section-subtitle{
  text-align:center;color:var(--text-subtitle);
  font-size:0.95rem;margin-bottom:var(--space-xl)
}
.accent{color:var(--accent)}
.glow-text{text-shadow:0 0 30px var(--accent-glow)}

/* ============================================================
   5. COMPONENTS — 按钮
   ============================================================ */
.btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:var(--space-sm) 28px;border-radius:var(--radius-md);
  font-size:0.95rem;font-weight:600;cursor:pointer;
  transition:var(--transition-fast);border:none;
  user-select:none;
}
.btn:active{transform:translateY(-1px)}
.btn-primary{
  background:#e8b8a0;color:#1f242b;
  box-shadow:0 4px 20px rgba(232,184,160,0.25);
}
.btn-primary:hover{
  background:#f0c8b8;transform:translateY(-2px);
  box-shadow:0 8px 30px rgba(232,176,160,0.4);
}
.btn-outline{
  background:transparent;color:#f4f7fa;
  border:1.5px solid #a2b6c6;
}
.btn-outline:hover{
  background:var(--accent-dim);transform:translateY(-2px);
}

/* ============================================================
   6. COMPONENTS — 导航栏
   ============================================================ */
.navbar{
  position:fixed;top:0;left:0;width:100%;z-index:1000;
  background:var(--bg-nav);backdrop-filter:blur(16px);
  -webkit-backdrop-filter:blur(16px);
  border-bottom:1px solid var(--border-subtle);
  transition:background 0.3s,box-shadow 0.3s;
}
.navbar.scrolled{
  background:var(--bg-nav-scrolled);
  box-shadow:0 4px 30px rgba(0,0,0,0.5);
}
.navbar .container{
  display:flex;align-items:center;justify-content:space-between;
  height:70px;
}
.nav-logo{
  font-size:1.3rem;font-weight:800;color:var(--accent);
  letter-spacing:1px;z-index:1001;
}
.nav-logo span{color:var(--text-primary);font-weight:400;font-size:0.85rem;margin-left:8px}

/* 桌面导航链接 */
.nav-links{display:flex;gap:32px}
.nav-links a{
  font-size:0.92rem;font-weight:500;color:var(--text-dim);
  position:relative;padding:var(--space-xs) 0;
  transition:color 0.3s;
}
.nav-links a::after{
  content:"";position:absolute;bottom:0;left:0;width:0;height:2px;
  background:var(--accent);transition:width 0.3s ease;
}
.nav-links a:hover,.nav-links a.active{color:var(--accent)}
.nav-links a:hover::after,.nav-links a.active::after{width:100%}

/* 主题切换按钮 */
.theme-toggle{
  background:none;border:1px solid var(--border-medium);
  color:var(--text-dim);font-size:1.1rem;cursor:pointer;
  width:36px;height:36px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  transition:var(--transition-fast);margin-left:var(--space-md);
  z-index:1001;
}
.theme-toggle:hover{color:var(--accent);border-color:var(--accent)}

/* 汉堡菜单按钮 (移动端默认隐藏) */
.hamburger{
  display:none;flex-direction:column;justify-content:center;
  width:30px;height:24px;background:none;border:none;
  cursor:pointer;z-index:1001;padding:0;gap:5px;
}
.hamburger span{
  display:block;width:100%;height:2px;background:var(--text-heading);
  border-radius:2px;transition:transform 0.3s ease,opacity 0.3s ease;
  transform-origin:center;
}
.hamburger.open span:nth-child(1){
  transform:translateY(7px) rotate(45deg);
}
.hamburger.open span:nth-child(2){opacity:0}
.hamburger.open span:nth-child(3){
  transform:translateY(-7px) rotate(-45deg);
}

/* ============================================================
   7. COMPONENTS — Hero 首屏
   ============================================================ */
.hero{
  min-height:100vh;display:flex;align-items:center;
  background:radial-gradient(ellipse at 50% 0%,rgba(148,168,184,0.06) 0%,transparent 60%),
             radial-gradient(ellipse at 80% 80%,rgba(148,168,184,0.04) 0%,transparent 50%);
  position:relative;overflow:hidden;
}
/* 背景装饰网格 — 缓慢平移 */
.hero::before{
  content:"";position:absolute;top:0;left:0;width:200%;height:200%;
  background-image:linear-gradient(rgba(148,168,184,0.03) 1px,transparent 1px),
                   linear-gradient(90deg,rgba(148,168,184,0.03) 1px,transparent 1px);
  background-size:60px 60px;pointer-events:none;
  animation:gridDrift 25s linear infinite;
}
@keyframes gridDrift{
  0%{transform:translate(0,0)}
  100%{transform:translate(60px,60px)}
}
/* 浮动光点 */
.hero::after{
  content:"";position:absolute;top:20%;right:10%;width:400px;height:400px;
  background:radial-gradient(circle,rgba(148,168,184,0.08) 0%,transparent 70%);
  border-radius:50%;pointer-events:none;
  animation:floatOrb 8s ease-in-out infinite;
}
@keyframes floatOrb{
  0%,100%{transform:translate(0,0) scale(1)}
  33%{transform:translate(-40px,-30px) scale(1.05)}
  66%{transform:translate(30px,20px) scale(0.95)}
}
.hero-content{position:relative;z-index:1;max-width:800px}
.hero-badge{
  display:inline-block;padding:var(--space-xs) 18px;
  border:1px solid rgba(148,168,184,0.4);border-radius:var(--radius-pill);
  font-size:0.8rem;color:#e0e8ef;letter-spacing:2px;
  margin-bottom:28px;background:rgba(0,0,0,0.25);
  white-space:nowrap;
  text-shadow:0 2px 12px rgba(0,0,0,0.45);
}
.hero .hero-content h1{
  font-size:3.2rem;font-weight:800;color:#f4f7fa;
  line-height:1.25;margin-bottom:16px;
  text-shadow:0 2px 12px rgba(0,0,0,0.45);
}
.hero .hero-content h1 .name{color:#f0c4ac}
.hero .hero-content .hero-subtitle{
  font-size:1.25rem;font-weight:400;color:#dde4ec;
  margin-bottom:28px;line-height:1.8;
  text-shadow:0 2px 12px rgba(0,0,0,0.45);
}
.hero .hero-content .hero-subtitle .accent{color:inherit}
.hero-highlight{
  font-size:1rem;color:#b4c2cf;
  border-left:3px solid var(--accent);
  padding:16px 20px;margin-bottom:36px;
  background:rgba(15,22,30,0.35);
  backdrop-filter:blur(6px);
  -webkit-backdrop-filter:blur(6px);
  border-radius:var(--radius-sm);
  line-height:1.8;
  text-shadow:0 2px 12px rgba(0,0,0,0.45);
}
.hero-actions{display:flex;gap:16px;flex-wrap:wrap}

/* 右侧装饰 — 打字机动画 */
.hero-code-decor{
  position:absolute;right:60px;top:50%;transform:translateY(-50%);
  background:rgba(11,15,23,0.9);border:1px solid var(--border-medium);
  border-radius:var(--radius-sm);padding:var(--space-md) 28px;width:340px;
  font-family:"Fira Code","Cascadia Code","Consolas",monospace;
  font-size:0.78rem;line-height:1.9;color:var(--text-muted);
  backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
  box-shadow:0 20px 60px rgba(0,0,0,0.4);
  z-index:1;
}
.hero-code-decor .code-line{
  display:block;opacity:0;transform:translateX(8px);
}
.hero-code-decor .code-line.visible{
  animation:typeLine 0.4s ease forwards;
}
.hero-code-decor .code-line:nth-child(1).visible{animation-delay:0s}
.hero-code-decor .code-line:nth-child(2).visible{animation-delay:0.5s}
.hero-code-decor .code-line:nth-child(3).visible{animation-delay:1.0s}
.hero-code-decor .code-line:nth-child(4).visible{animation-delay:1.5s}
.hero-code-decor .code-line:nth-child(5).visible{animation-delay:2.0s}
.hero-code-decor .code-line:nth-child(6).visible{animation-delay:2.5s}
.hero-code-decor .code-line:nth-child(7).visible{animation-delay:3.0s}
.hero-code-decor .code-line:nth-child(8).visible{animation-delay:3.5s}
.hero-code-decor .code-line:nth-child(9).visible{animation-delay:4.0s}
.hero-code-decor .code-line:nth-child(10).visible{animation-delay:4.5s}
@keyframes typeLine{
  to{opacity:1;transform:translateX(0)}
}
.hero-code-decor .kw{color:#94a8b8}
.hero-code-decor .str{color:#f1c40f}
.hero-code-decor .fn{color:#3498db}
.hero-code-decor .cmt{color:#555}
.cursor-blink{animation:blink 1s step-end infinite}
@keyframes blink{50%{opacity:0}}

/* 向下滚动提示 — 可点击 */
.scroll-hint{
  position:absolute;bottom:40px;left:50%;transform:translateX(-50%);
  display:flex;flex-direction:column;align-items:center;gap:8px;
  color:var(--text-muted);font-size:0.75rem;
  animation:bounceDown 2s ease-in-out infinite;
  cursor:pointer;border:none;background:none;
}
.scroll-hint .arrow{font-size:1.2rem}
@keyframes bounceDown{
  0%,100%{transform:translateX(-50%) translateY(0)}
  50%{transform:translateX(-50%) translateY(10px)}
}

/* ============================================================
   8. COMPONENTS — 卡片基类 (skill/project/contact 共用)
   ============================================================ */
.card-base{
  background:var(--bg-card);
  border:1px solid var(--border-subtle);
  border-radius:var(--radius-lg);
  transition:var(--transition-card);
  position:relative;overflow:hidden;
  will-change:transform;
  backdrop-filter:blur(14px);
  -webkit-backdrop-filter:blur(14px);
}
.card-base::before{
  content:"";position:absolute;top:0;left:0;width:100%;height:100%;
  pointer-events:none;opacity:0;transition:opacity 0.4s;
  border-radius:inherit;
  box-shadow:inset 0 0 0 2px var(--border-glow),0 0 40px var(--accent-dim);
}
.card-base:hover::before{opacity:1}
.card-base:hover{
  transform:translateY(-6px);
  border-color:var(--border-glow);
}

/* ============================================================
   9. COMPONENTS — 技术技能
   ============================================================ */
.skills-section{padding:var(--space-2xl) 0;position:relative}
.skills-grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:var(--space-md);
}
.skill-card{
  border-radius:var(--radius-lg);padding:32px 28px;
  cursor:pointer;
  will-change:transform;
}
.skill-card:hover .skill-icon{transform:scale(1.15);color:var(--accent)}
.skill-icon{
  font-size:2rem;margin-bottom:16px;transition:var(--transition-card);
  display:block;color:var(--text-dim);
}
.skill-card h3,.skill-card .skill-title{
  font-size:1.1rem;color:var(--text-heading);margin-bottom:var(--space-sm);
  font-weight:700;
}
.skill-card p{font-size:0.9rem;color:var(--text-muted);line-height:1.8}
.skill-card .skill-tags{
  display:flex;flex-wrap:wrap;gap:8px;margin-top:16px;
}
.skill-tag{
  font-size:0.72rem;padding:3px 10px;border-radius:var(--radius-sm);
  background:var(--accent-dim);color:var(--accent);
  border:1px solid var(--border-medium);
}

/* 技能进度条 */
.skill-bar{
  width:100%;height:4px;background:rgba(148,168,184,0.1);
  border-radius:2px;margin-top:var(--space-sm);overflow:hidden;
}
.skill-bar-fill{
  height:100%;background:var(--accent);border-radius:2px;
  transition:width 1s var(--ease-out-expo);
  width:0;
}
.skill-bar-fill.animated{width:var(--fill-width)}

/* AI 核心卡片高亮 */
.skill-card.featured{
  border-color:var(--border-glow);
  background:var(--bg-card-featured);
}
.skill-card.featured::after{
  content:"核心";position:absolute;top:16px;right:16px;
  font-size:0.7rem;color:#1a1a1a;background:#e8b0a0;
  padding:2px 10px;border-radius:20px;font-weight:700;letter-spacing:1px;
}

/* ============================================================
   10. COMPONENTS — 项目实践
   ============================================================ */
.projects-section{
  padding:var(--space-2xl) 0;background:rgba(148,168,184,0.02);
  border-top:1px solid rgba(148,168,184,0.06);
  border-bottom:1px solid rgba(148,168,184,0.06);
}
.project-card{
  border-radius:var(--radius-xl);padding:var(--space-lg);margin-bottom:32px;
  display:grid;grid-template-columns:1fr 1fr;gap:var(--space-lg);
  align-items:start;cursor:pointer;
  will-change:transform;
}
.project-card:last-child{margin-bottom:0}
.project-badge{
  display:inline-block;padding:4px 14px;border-radius:var(--radius-sm);
  font-size:0.72rem;font-weight:700;letter-spacing:1px;margin-bottom:16px;
}
.project-badge.key{
  background:rgba(148,168,184,0.12);color:var(--accent);
  border:1px solid var(--border-glow);
}
.project-badge.normal{
  background:rgba(136,146,176,0.1);color:var(--text-dim);
  border:1px solid rgba(136,146,176,0.2);
}
.project-info h3,.project-info .project-title{
  font-size:1.4rem;color:var(--text-heading);margin-bottom:10px;
}
.project-info .project-subtitle{color:var(--accent);font-size:0.85rem;margin-bottom:20px}
.project-info .project-desc{
  color:var(--text-dim);font-size:0.92rem;line-height:1.9;margin-bottom:20px;
}
.project-info .project-desc ul{margin-top:8px;display:flex;flex-direction:column;gap:6px}
.project-info .project-desc ul li{position:relative;padding-left:18px}
.project-info .project-desc ul li::before{
  content:"▹";position:absolute;left:0;color:var(--accent);
}
.project-tech{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.project-tech span{
  font-size:0.75rem;padding:4px var(--space-sm);border-radius:var(--radius-sm);
  background:var(--accent-dim);color:var(--accent);
  border:1px solid var(--border-medium);
  font-family:"Fira Code","Cascadia Code","Consolas",monospace;
}
/* 项目详情面板 */
.project-detail{
  background:var(--bg-panel);border-radius:var(--radius-sm);
  border:1px solid rgba(148,168,184,0.1);padding:var(--space-md);
  font-size:0.85rem;transition:max-height 0.4s ease,opacity 0.4s ease;
  overflow:hidden;
  backdrop-filter:blur(10px);
  -webkit-backdrop-filter:blur(10px);
}
.project-detail--collapsed{max-height:0!important;opacity:0;padding:0 24px;border-width:0}
.project-detail h4{
  color:var(--text-heading);font-size:0.9rem;margin-bottom:var(--space-sm);
  display:flex;align-items:center;gap:8px;
}
.project-detail h4::before{
  content:"";display:block;width:8px;height:8px;
  background:var(--accent);border-radius:50%;
}
.project-detail .detail-item{margin-bottom:18px}
.project-detail .detail-label{color:var(--text-muted);font-size:0.75rem;margin-bottom:4px}
.project-detail .detail-value{color:var(--text-primary);font-size:0.88rem;line-height:1.7}
.project-detail .metric{
  font-size:2rem;font-weight:800;color:var(--accent);
  font-family:"Fira Code","Consolas",monospace;
}
.project-detail .metric small{font-size:0.8rem;color:var(--text-dim);font-weight:400}

/* 展开/收起按钮 */
.toggle-detail{
  display:inline-flex;align-items:center;gap:6px;
  background:none;border:1px solid var(--border-medium);
  color:var(--accent);font-size:0.78rem;cursor:pointer;
  padding:4px 12px;border-radius:var(--radius-sm);
  margin-top:8px;transition:var(--transition-fast);
}
.toggle-detail:hover{background:var(--accent-dim)}
.toggle-detail .toggle-icon{
  transition:transform 0.3s ease;display:inline-block;
}
.toggle-detail.open .toggle-icon{transform:rotate(180deg)}

/* ============================================================
   11. COMPONENTS — 在校经历 (时间线)
   ============================================================ */
.experience-section{padding:var(--space-2xl) 0}
.timeline{position:relative;max-width:700px;margin:0 auto}
.timeline::before{
  content:"";position:absolute;left:20px;top:0;height:100%;width:2px;
  background:linear-gradient(to bottom,transparent,rgba(148,168,184,0.4),transparent);
}
.timeline-item{
  position:relative;padding-left:56px;margin-bottom:48px;
}
.timeline-item:last-child{margin-bottom:0}
.timeline-dot{
  position:absolute;left:13px;top:4px;width:16px;height:16px;
  border-radius:50%;background:var(--accent);
  box-shadow:0 0 16px rgba(148,168,184,0.5);
}
.timeline-content{
  background:var(--bg-card);border:1px solid var(--border-subtle);
  border-radius:var(--radius-sm);padding:28px 30px;
  transition:var(--transition-card);cursor:pointer;
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
}
.timeline-content:hover{
  border-color:var(--border-glow);transform:translateX(6px);
  box-shadow:0 8px 30px rgba(0,0,0,0.3);
}
.timeline-content h3{font-size:1.1rem;color:var(--text-heading);margin-bottom:6px}
.timeline-content .role{
  font-size:0.85rem;color:var(--accent);margin-bottom:var(--space-sm);font-weight:600;
}
.timeline-content p{font-size:0.9rem;color:var(--text-dim);line-height:1.8}

/* ============================================================
   12. COMPONENTS — 联系方式
   ============================================================ */
.contact-section{
  padding:var(--space-2xl) 0;background:rgba(148,168,184,0.02);
  border-top:1px solid rgba(148,168,184,0.06);
}
.contact-grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:var(--space-md);
  max-width:900px;margin:0 auto;
}
.contact-card{
  border-radius:var(--radius-lg);padding:32px;text-align:center;
  cursor:pointer;
  animation:breatheGlow 3s ease-in-out infinite;
  will-change:transform;
}
@keyframes breatheGlow{
  0%,100%{box-shadow:0 0 0 0 rgba(148,168,184,0)}
  50%{box-shadow:0 0 20px 4px rgba(148,168,184,0.08)}
}
.contact-card:active{transform:scale(0.97)}
.contact-icon{font-size:2rem;margin-bottom:14px}
.contact-card h4{color:var(--text-heading);font-size:1rem;margin-bottom:8px}
.contact-card p{color:var(--text-muted);font-size:0.88rem}
.contact-card a{color:var(--accent);font-size:0.88rem;transition:color 0.3s}
.contact-card a:hover{color:var(--accent-hover)}
.contact-value{color:var(--text-primary);font-size:0.88rem}
.contact-note{font-size:0.75rem;margin-top:4px;color:var(--text-subtitle)}

/* ============================================================
   13. COMPONENTS — 回到顶部按钮
   ============================================================ */
#back-to-top{
  position:fixed;bottom:40px;right:40px;z-index:999;
  width:44px;height:44px;border-radius:50%;
  background:#e8b0a0;color:#1a1a1a;
  border:none;cursor:pointer;font-size:1.2rem;
  display:flex;align-items:center;justify-content:center;
  box-shadow:0 4px 16px rgba(232,176,160,0.3);
  opacity:0;transform:translateY(20px);
  transition:opacity 0.3s ease,transform 0.3s ease,background 0.3s;
  pointer-events:none;
}
#back-to-top.visible{
  opacity:1;transform:translateY(0);pointer-events:auto;
}
#back-to-top:hover{background:#f0c8b8;transform:translateY(-3px)}

/* ============================================================
   14. COMPONENTS — Footer
   ============================================================ */
.footer{
  text-align:center;padding:32px 0;color:#555;font-size:0.8rem;
  border-top:1px solid rgba(148,168,184,0.06);
}
.footer span{color:var(--accent)}

/* ============================================================
   15. UTILITIES — 滚动入场动画
   ============================================================ */
.fade-up{
  opacity:0;transform:translateY(40px);
  transition:opacity 0.7s ease,transform 0.7s ease;
  will-change:transform,opacity;
}
.fade-up.visible{opacity:1;transform:translateY(0)}

/* ============================================================
   16. RESPONSIVE — max-width: 1200px
   ============================================================ */
@media(max-width:1200px){
  .hero-code-decor{display:none}
  .project-card{grid-template-columns:1fr}
  .skills-grid{grid-template-columns:repeat(2,1fr)}
  .hero .hero-content h1{font-size:2.6rem}
}

/* ============================================================
   17. RESPONSIVE — max-width: 768px (平板 + 移动端)
   ============================================================ */
@media(max-width:768px){
  .container{padding:0 20px}
  .section-title{font-size:1.6rem}
  .section-subtitle{font-size:0.85rem;margin-bottom:40px}

  /* 汉堡菜单 */
  .hamburger{display:flex}
  .nav-links{
    position:fixed;top:0;left:0;width:100%;height:100vh;
    flex-direction:column;justify-content:center;align-items:center;
    gap:40px;background:var(--bg-nav-scrolled);
    backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);
    transform:translateX(100%);transition:transform 0.4s var(--ease-out-expo);
    z-index:1000;
  }
  .nav-links.nav-links--open{transform:translateX(0)}
  .nav-links a{font-size:1.2rem}
  .theme-toggle{margin-left:0}

  /* Hero */
  .hero .hero-content h1{font-size:2.2rem}
  .hero .hero-content .hero-subtitle{font-size:1rem}
  .hero-highlight{font-size:0.9rem}

  /* Grid */
  .skills-grid{grid-template-columns:1fr}
  .contact-grid{grid-template-columns:1fr;max-width:400px}
  .project-card{padding:var(--space-md)}

  /* Timeline */
  .timeline-item{padding-left:40px}
  .timeline::before{left:14px}
  .timeline-dot{left:7px}

  /* Back to top */
  #back-to-top{bottom:24px;right:24px;width:40px;height:40px}
}

/* ============================================================
   18. RESPONSIVE — max-width: 576px (大屏手机)
   ============================================================ */
@media(max-width:576px){
  .section-title{font-size:1.4rem}
  .section-subtitle{margin-bottom:32px}

  .skills-section,.projects-section,
  .experience-section,.contact-section{padding:var(--space-xl) 0}

  .skill-card{padding:24px 20px}
  .skill-card h3,.skill-card .skill-title{font-size:1rem}
  .skill-card p{font-size:0.82rem}

  .project-card{padding:20px}
  .project-info h3,.project-info .project-title{font-size:1.15rem}
  .project-info .project-desc{font-size:0.85rem}
  .project-detail{padding:16px;font-size:0.8rem}
  .project-detail .metric{font-size:1.5rem}

  .contact-card{padding:24px 20px}
  .contact-icon{font-size:1.6rem}

  .timeline-content{padding:20px}
  .timeline-content h3{font-size:1rem}

  .hero .hero-content h1{font-size:2rem}
  .hero-actions{flex-direction:column}
  .hero-actions .btn{width:100%;justify-content:center}
  .hero-badge{font-size:0.72rem;padding:4px 14px}

  .navbar .container{height:60px}
}

/* ============================================================
   19. RESPONSIVE — max-width: 375px (小屏手机)
   ============================================================ */
@media(max-width:375px){
  .hero .hero-content h1{font-size:1.8rem}
  .hero .hero-content .hero-subtitle{font-size:0.88rem}
  .hero-highlight{font-size:0.8rem;padding:10px 14px}
  .hero-badge{white-space:nowrap;font-size:0.68rem}
  .hero-actions{gap:10px}

  .section-title{font-size:1.3rem}
  .section-subtitle{font-size:0.78rem}

  .skill-card{padding:18px 14px}
  .skill-card h3,.skill-card .skill-title{font-size:0.92rem}
  .skill-card p{font-size:0.78rem}
  .skill-tag{font-size:0.68rem;padding:2px 8px}

  .project-card{padding:14px;margin-bottom:20px}
  .project-info h3,.project-info .project-title{font-size:1.05rem}
  .project-info .project-desc{font-size:0.78rem}
  .project-detail{padding:12px;font-size:0.75rem}
  .project-detail .metric{font-size:1.3rem}
  .project-tech span{font-size:0.7rem;padding:3px 8px}
  .toggle-detail{font-size:0.72rem;padding:3px 10px}

  .contact-card{padding:18px 14px}
  .contact-icon{font-size:1.4rem}
  .contact-card h4{font-size:0.9rem}
  .contact-card p,.contact-card a{font-size:0.78rem}

  .timeline-item{padding-left:34px}
  .timeline-dot{left:5px;width:12px;height:12px}
  .timeline-content{padding:16px}
  .timeline-content h3{font-size:0.92rem}

  .nav-logo{font-size:1.1rem}
  .nav-logo span{font-size:0.7rem}

  #back-to-top{bottom:16px;right:16px;width:36px;height:36px;font-size:1rem}
}

/* ============================================================
   20. VISUAL — Canvas 粒子背景
   ============================================================ */
#particle-canvas{
  position:absolute;top:0;left:0;width:100%;height:100%;
  z-index:0;pointer-events:none;
}

/* ============================================================
   21. VISUAL — 噪点纹理叠加 (玻璃拟态 2.0)
   ============================================================ */
body::before{
  content:"";position:fixed;top:0;left:0;width:100%;height:100%;
  background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.5'/%3E%3C/svg%3E");
  background-size:256px 256px;opacity:0.025;pointer-events:none;z-index:0;
  mix-blend-mode:overlay;
}
[data-theme="light"] body::before{opacity:0.04;mix-blend-mode:multiply}

/* 增强玻璃拟态饱和度 */
.navbar{backdrop-filter:blur(16px) saturate(1.4);-webkit-backdrop-filter:blur(16px) saturate(1.4)}
.hero-code-decor{backdrop-filter:blur(12px) saturate(1.3);-webkit-backdrop-filter:blur(12px) saturate(1.3)}

/* ============================================================
   22. VISUAL — 渐变跟随光标
   ============================================================ */
.cursor-glow{
  position:fixed;top:0;left:0;width:100%;height:100%;
  pointer-events:none;z-index:0;
  background:radial-gradient(circle 400px at var(--cursor-x,50%) var(--cursor-y,50%),rgba(148,168,184,0.04) 0%,transparent 70%);
  transition:background 0.15s ease-out;
}

/* ============================================================
   23. VISUAL — 3D Tilt 卡片视差
   ============================================================ */
.skill-card.tilt-enabled,
.project-card.tilt-enabled{
  transform-style:preserve-3d;
  transition:transform 0.6s cubic-bezier(0.23,1,0.32,1),border-color 0.4s;
}
.skill-card.tilt-enabled>*,
.project-card.tilt-enabled>*{transform:translateZ(20px)}
.skill-card.tilt-enabled::before,
.project-card.tilt-enabled::before{transform:translateZ(1px)}

/* ============================================================
   24. VISUAL — 微交互动效
   ============================================================ */
/* 标签 hover 弹跳 */
.skill-tag{
  transition:transform 0.2s ease,box-shadow 0.2s ease,background 0.2s ease;
}
.skill-tag:hover{
  transform:translateY(-2px);
  box-shadow:0 4px 12px rgba(148,168,184,0.25);
  background:rgba(148,168,184,0.16);
}

/* 图标旋转 */
.skill-card:hover .skill-icon,
.contact-card:hover .contact-icon{
  transition:transform 0.6s var(--ease-out-expo);
  transform:rotate(360deg);
}
.skill-bar-fill .bar-label{
  position:absolute;right:0;top:-20px;font-size:0.7rem;
  color:var(--accent);font-weight:700;font-family:"Fira Code","Consolas",monospace;
  opacity:0;transform:translateY(4px);transition:opacity 0.3s,transform 0.3s;
}
.skill-bar-fill.animated .bar-label{
  opacity:1;transform:translateY(0);
}

/* 进度条计数动画 */
   25. COMPONENTS — 页面预加载动画
   ============================================================ */
.preloader{
  position:fixed;top:0;left:0;width:100%;height:100%;
  background:var(--bg-primary);z-index:9999;
  display:flex;flex-direction:column;align-items:center;justify-content:center;
  gap:24px;transition:opacity 0.5s ease,visibility 0.5s ease;
}
.preloader--hidden{opacity:0;visibility:hidden;pointer-events:none}
.preloader-dots{display:flex;gap:10px}
.preloader-dot{
  width:12px;height:12px;background:var(--accent);border-radius:50%;
  animation:preloadPulse 1.2s ease-in-out infinite;
}
.preloader-dot:nth-child(2){animation-delay:0.2s}
.preloader-dot:nth-child(3){animation-delay:0.4s}
@keyframes preloadPulse{
  0%,100%{transform:scale(0.6);opacity:0.4}
  50%{transform:scale(1.2);opacity:1}
}
.preloader-text{
  color:var(--accent);font-family:"Fira Code","Consolas",monospace;
  font-size:0.85rem;letter-spacing:2px;
  animation:preloadText 2s ease-in-out infinite;
}
@keyframes preloadText{
  0%,100%{opacity:0.5}
  50%{opacity:1}
}

/* ============================================================
   26. COMPONENTS — 快捷键提示面板
   ============================================================ */
.shortcuts-overlay{
  position:fixed;top:0;left:0;width:100%;height:100%;
  background:rgba(0,0,0,0.7);z-index:10000;
  display:flex;align-items:center;justify-content:center;
  opacity:0;visibility:hidden;pointer-events:none;
  transition:opacity 0.3s ease,visibility 0.3s ease;
}
.shortcuts-overlay--open{opacity:1;visibility:visible;pointer-events:auto}
.shortcuts-panel{
  background:var(--bg-card);border:1px solid var(--border-glow);
  border-radius:var(--radius-xl);padding:40px;max-width:420px;width:90%;
  box-shadow:0 20px 60px rgba(0,0,0,0.5);
}
.shortcuts-panel h3{color:var(--text-heading);margin-bottom:20px;font-size:1.1rem;text-align:center}
.shortcuts-panel kbd{
  display:inline-block;padding:2px 10px;background:rgba(148,168,184,0.15);
  border:1px solid var(--border-medium);border-radius:var(--radius-sm);
  color:var(--accent);font-family:"Fira Code","Consolas",monospace;
  font-size:0.82rem;margin-right:8px;min-width:28px;text-align:center;
}
.shortcuts-list{display:flex;flex-direction:column;gap:14px}
.shortcuts-list li{display:flex;align-items:center;color:var(--text-dim);font-size:0.9rem}
.shortcuts-list li span{flex:1}
.shortcuts-close{
  display:block;margin:24px auto 0;background:#e8b0a0;color:#1a1a1a;
  border:none;padding:8px 28px;border-radius:var(--radius-md);cursor:pointer;
  font-size:0.85rem;font-weight:600;transition:background 0.3s;
}
.shortcuts-close:hover{background:#f0c8b8}

/* ============================================================
   27. VISUAL — 滚动驱动视差 (渐进增强)
   ============================================================ */
@supports (animation-timeline: scroll()){
  @keyframes heroParallax{
    0%{transform:translateY(0)}
    100%{transform:translateY(-60px)}
  }
  .hero-content{
    animation:heroParallax linear both;
    animation-timeline:scroll();
    animation-range:0% 40%;
  }
  @keyframes fadeUpStagger{
    0%{opacity:0;transform:translateY(40px)}
    10%{opacity:1;transform:translateY(0)}
  }
}