* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
}
:root {
    --primary-color: #165DFF;
    --primary-light: #4080FF;
    --bg-color: #F5F7FA;
    --card-bg: #FFFFFF;
    --text-primary: #1D2129;
    --text-secondary: #4E5969;
    --text-tertiary: #86909C;
    --border-color: #E5E6EB;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-full: 999px;
    --transition: all 0.28s ease;
}
[data-theme="dark"] {
    --primary-color: #4080FF;
    --primary-light: #6AA1FF;
    --bg-color: #121212;
    --card-bg: #1E1E1E;
    --text-primary: #F2F3F5;
    --text-secondary: #C9CDD4;
    --text-tertiary: #86909C;
    --border-color: #35363A;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.4);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.5);
}
html { scroll-behavior: smooth; }
body {
    background: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    transition: var(--transition);
    padding-bottom: 50px;
}
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}
.section-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--primary-color);
    display: inline-block;
}
.card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    padding: 22px 24px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}
.card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 18px;
    border-radius: var(--radius-md);
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    border: none;
}
.btn-primary {
    background: var(--primary-color);
    color: #fff;
}
.btn-primary:hover {
    background: var(--primary-light);
    transform: scale(1.03);
}
.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}
.btn-outline:hover {
    background: var(--primary-color);
    color: #fff;
}
header {
    position: sticky;
    top: 0;
    background: var(--card-bg);
    box-shadow: var(--shadow-sm);
    z-index: 999;
}
.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 65px;
}
.nav-logo {
    font-size: 18px;
    font-weight: 700;
    color: var(--primary-color);
}
.nav-menu {
    display: flex;
    gap: 24px;
    list-style: none;
}
.nav-menu li a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}
.nav-menu li a:hover {
    color: var(--primary-color);
}
.nav-right { display: flex; align-items: center; gap: 12px; }
.theme-toggle {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    border: none;
    background: var(--bg-color);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
}
.theme-toggle:hover { background: var(--border-color); }
.hamburger { display: none; flex-direction: column; gap: 4px; cursor: pointer; }
.hamburger span { width: 24px; height: 3px; background: var(--text-primary); border-radius: 2px; }

.hero-section { padding: 50px 0 30px; }
.hero-container {
    display: grid;
    grid-template-columns: 1fr 260px;
    gap: 40px;
    align-items: center;
}
.hero-content h1 {
    font-size: 40px;
    font-weight: 800;
    margin-bottom: 8px;
    line-height: 1.2;
}
.hero-title {
    font-size: 20px;
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 18px;
}
.hero-contact {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-bottom: 22px;
}
.contact-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 7px 14px;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 30px;
    color: var(--text-secondary);
    transition: var(--transition);
    cursor: pointer;
    text-decoration: none; /* 去掉下划线 */
}
.contact-item a {
    text-decoration: none; /* 确保a标签也无下划线 */
    color: inherit;
}
.contact-item:hover {
    background: var(--primary-color);
    color: #fff;
    transform: scale(1.04);
}
.hero-avatar {
    width: 260px;
    height: 260px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    border: 3px solid var(--card-bg);
    transition: var(--transition);
    align-self: center;
}
.hero-avatar:hover { transform: scale(1.02); }
.hero-avatar img { width: 100%; height: 100%; object-fit: cover; }

.about-section, .experience-section, .skills-section, .cert-section, .education-section {
    padding-bottom: 32px;
}
.about-text {
    font-size: 15px;
    line-height: 1.75;
    color: var(--text-secondary);
}
.about-text strong {
    font-weight: 700;
    color: var(--primary-color);
}

.timeline { position: relative; padding-left: 36px; }
.timeline::before { content: ''; position: absolute; left: 0; top: 0; bottom: 0; width: 2px; background: var(--primary-color); opacity: 0.2; }
.timeline-item { position: relative; margin-bottom: 24px; }
.timeline-item::before {
    content: '';
    position: absolute;
    left: -44px; top: 0;
    width: 14px; height: 14px;
    border-radius: 50%;
    background: var(--primary-color);
    border: 3px solid var(--bg-color);
}
.timeline-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 8px;
    flex-wrap: wrap;
    gap: 6px;
}
.timeline-company { font-size: 17px; font-weight: 700; }
.timeline-position { font-size: 15px; color: var(--primary-color); font-weight: 600; }
.timeline-time { font-size: 13px; color: var(--text-tertiary); }
.timeline-desc { font-size: 15px; color: var(--text-secondary); margin-bottom: 12px; }
.project-item {
    padding: 12px;
    background: var(--bg-color);
    border-radius: var(--radius-md);
    margin-bottom: 8px;
    transition: var(--transition);
}
.project-item:hover {
    transform: translateX(4px);
    box-shadow: var(--shadow-sm);
}
.project-title { font-weight: 600; font-size: 15px; margin-bottom: 4px; }
.project-desc { font-size: 13px; color: var(--text-secondary); }

.skills-grid { display: grid; grid-template-columns: repeat(auto-fit,minmax(280px,1fr)); gap: 24px; }
.skill-category-title { font-size: 16px; font-weight: 700; margin-bottom: 12px; }
.skill-item { margin-bottom: 12px; }
.skill-header { display: flex; justify-content: space-between; margin-bottom: 6px; }
.skill-name { font-size: 14px; color: var(--text-secondary); }
.skill-percent { font-weight: 600; color: var(--primary-color); }
.skill-bar { width: 100%; height: 7px; background: var(--border-color); border-radius: 10px; overflow: hidden; }
.skill-progress { height: 100%; background: linear-gradient(90deg,var(--primary-color),var(--primary-light)); border-radius: 10px; transition: width 1s ease; }

.cert-grid { display: grid; grid-template-columns: repeat(auto-fit,minmax(260px,1fr)); gap: 16px; }
.cert-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 16px;
    background: var(--card-bg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}
.cert-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}
.cert-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    background: rgba(22,93,255,0.1);
    color: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
}
.cert-content h4 { font-weight: 600; margin-bottom: 4px; font-size: 15px; }
.cert-content p { font-size: 13px; color: var(--text-tertiary); }

footer {
    padding: 28px 0;
    text-align: center;
    color: var(--text-tertiary);
    border-top: 1px solid var(--border-color);
}
.back-to-top {
    position: fixed;
    bottom: 25px;
    right: 25px;
    width: 46px;
    height: 46px;
    border-radius: 50%;
    background: var(--primary-color);
    color: #fff;
    border: none;
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    cursor: pointer;
}
.back-to-top.show { opacity: 1; visibility: visible; }
.back-to-top:hover {
    background: var(--primary-light);
    transform: translateY(-3px);
}
.copy-toast {
    position: fixed;
    top: 70px;
    left: 50%;
    transform: translateX(-50%);
    padding: 10px 20px;
    background: var(--primary-color);
    color: #fff;
    border-radius: var(--radius-md);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}
.copy-toast.show { opacity: 1; visibility: visible; }

@media(max-width:992px){
    .hero-container{grid-template-columns:1fr;gap:30px;}
    .hero-avatar{margin:0 auto;order: -1;}
    .nav-menu{position:fixed;top:65px;left:0;right:0;flex-direction:column;background:var(--card-bg);padding:20px;gap:16px;transform:translateY(-100%);opacity:0;visibility:hidden;}
    .nav-menu.show{transform:translateY(0);opacity:1;visibility:visible;}
    .hamburger{display:flex;}
}
@media(max-width:576px){
    .hero-content h1{font-size:32px;}
    .hero-title{font-size:18px;}
    .section-title{font-size:21px;}
    .card{padding:18px 16px;}
    .timeline{padding-left:28px;}
    .timeline-item::before{left:-36px;}
    .cert-grid,.skills-grid{grid-template-columns:1fr;}
    .hero-contact{flex-direction:column;}
}
@media print{
    header,.back-to-top,.theme-toggle,.btn,.contact-item,.copy-toast{display:none!important;}
    body{background:#fff!important;color:#000!important;}
    .card{box-shadow:none!important;border:1px solid #eee;}
}
footer a {
    text-decoration: none !important;
    color: var(--text-tertiary) !important;
    transition: all 0.3s ease;
}

footer a:hover {
    color: var(--primary-color) !important;
}