/* 全局样式：平滑滚动+背景效果（未来科技风核心） */
html {
    scroll-behavior: smooth;
    scrollbar-width: thin;
    scrollbar-color: #00f0ff #0a0e17;
}

body {
    font-family: 'Roboto Mono', monospace;
    background-color: #0a0e17; /* 深色背景 */
    background-image: 
        radial-gradient(circle at 20% 30%, rgba(0,240,255,0.1) 0%, transparent 20%),
        radial-gradient(circle at 80% 70%, rgba(157,0,255,0.1) 0%, transparent 20%);
    background-attachment: fixed;
    color: #f5f5f5; /* 浅色文字 */
    margin: 0;
    padding: 0;
}

/* 滚动条美化（Chrome/Safari） */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
::-webkit-scrollbar-track {
    background: #0a0e17;
}
::-webkit-scrollbar-thumb {
    background: #00f0ff; /* 霓虹青色 */
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
    background: #9d00ff; /* 霓虹紫色 */
}

/* 动画：淡入（滚动触发） */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.active {
    opacity: 1;
    transform: translateY(0);
}

/* 霓虹分割线 */
.divider-neon {
    height: 1px;
    background: linear-gradient(90deg, transparent, #00f0ff, transparent);
    width: 80%;
    margin: 2rem auto;
}

/* 自定义工具类（统一复用） */
.text-gradient {
    background-clip: text;
    -webkit-background-clip: text;
    color: transparent;
    background-image: linear-gradient(to right, #00f0ff, #9d00ff); /* 霓虹渐变色 */
}

.border-neon {
    border: 1px solid rgba(0, 240, 255, 0.5);
    box-shadow: 0 0 5px #00f0ff, 0 0 20px rgba(0, 240, 255, 0.2);
}

.card-tech {
    background-color: rgba(30, 37, 50, 0.7); /* 深色半透明卡片 */
    backdrop-filter: blur(10px); /* 玻璃拟态 */
    border-radius: 0.5rem;
    padding: 1.5rem;
    border: 1px solid rgba(0, 240, 255, 0.3);
    box-shadow: 0 0 8px rgba(0,240,255,0.4), 0 0 20px rgba(157,0,255,0.2);
    transition: all 0.3s ease;
}
.card-tech:hover {
    box-shadow: 0 0 5px #9d00ff, 0 0 20px rgba(157,0,255,0.3);
    border-color: rgba(157, 0, 255, 0.5);
}

.section-padding {
    padding: 4rem 1rem;
}
@media (min-width: 768px) {
    .section-padding {
        padding: 6rem 1rem;
    }
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* 导航栏样式（统一） */
nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 50;
    transition: all 0.3s ease;
    background-color: rgba(10, 14, 23, 0.8);
    backdrop-filter: blur(10px);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    text-decoration: none;
}

.nav-links {
    display: none;
    gap: 2rem;
}
@media (min-width: 768px) {
    .nav-links {
        display: flex;
    }
}

.nav-links a {
    color: #f5f5f5;
    text-decoration: none;
    transition: color 0.3s ease;
}
.nav-links a:hover {
    color: #00f0ff; /*  hover变霓虹青色 */
}

.menu-btn {
    display: block;
    background: none;
    border: none;
    color: #f5f5f5;
    font-size: 1.5rem;
    cursor: pointer;
}
@media (min-width: 768px) {
    .menu-btn {
        display: none;
    }
}

.mobile-menu {
    display: none;
    background-color: rgba(30, 37, 50, 0.9);
    backdrop-filter: blur(10px);
    padding: 1rem;
}
.mobile-menu.active {
    display: block;
}

.mobile-links {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    padding: 1rem 0;
}
.mobile-links a {
    color: #f5f5f5;
    text-decoration: none;
    transition: color 0.3s ease;
}
.mobile-links a:hover {
    color: #00f0ff;
}

/* 页脚样式（统一） */
footer {
    background-color: rgba(10, 14, 23, 0.8);
    backdrop-filter: blur(10px);
    padding: 2rem 1rem;
    margin-top: 4rem;
}

.footer-container {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}
@media (min-width: 768px) {
    .footer-container {
        flex-direction: row;
    }
}

.social-links {
    display: flex;
    gap: 1.5rem;
}
.social-links a {
    color: #888;
    text-decoration: none;
    font-size: 1.5rem;
    transition: color 0.3s ease;
}
.social-links a:hover {
    color: #00f0ff;
}

/* 证书展示区样式（skills.html专用） */
.cert-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}
@media (min-width: 768px) {
    .cert-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}
@media (min-width: 1024px) {
    .cert-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.cert-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 1.5rem;
}

.cert-icon {
    font-size: 3rem;
    color: #00f0ff;
    margin-bottom: 1rem;
}

.cert-title {
    font-size: 1.2rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.cert-desc {
    color: #aaa;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.cert-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: #00f0ff;
    text-decoration: none;
    transition: color 0.3s ease;
}
.cert-link:hover {
    color: #9d00ff;
}

/* 作品展示占位样式（works.html专用） */
.works-placeholder {
    min-height: 50vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 2rem;
}

.works-icon {
    font-size: 5rem;
    color: rgba(0, 240, 255, 0.3);
    margin-bottom: 2rem;
}

/* 复制功能样式（contact.html专用） */
.copyable {
    cursor: pointer;
    transition: color 0.3s ease;
}
.copyable:hover {
    color: #00f0ff;
}

<!-- 2. 添加 CSS 样式（可放在 <style> 标签或外部 CSS 文件中） -->
<style>
/* 父容器：占满屏幕可视区域，同时让内容居中 */
.qr-container {
  /* 1. 让容器铺满屏幕（如果只需在某个区域居中，可删除这3行，改设固定宽高） */
  position: fixed;  /* 固定在屏幕中，不随滚动变化 */
  top: 0;
  left: 0;
  width: 100vw;    /* 宽度 = 屏幕宽度 */
  height: 100vh;   /* 高度 = 屏幕高度 */

  /* 2. Flex 核心居中代码 */
  display: flex;        /* 启用 Flex 布局 */
  justify-content: center;  /* 水平居中 */
  align-items: center;      /* 垂直居中 */

  /* 可选：避免二维码遮挡其他内容（按需添加） */
  z-index: 10;  /* 数值越大，越靠前；若有遮挡可调整 */
}
</style>