/* ==============================
   变量 & 主题
   ============================== */
:root {
    /* 主色调 */
    --primary-color: #6c5ce7;
    --primary-dark: #5a4bd1;
    --primary-light: #a29bfe;
    --gradient-primary: linear-gradient(135deg, #6c5ce7 0%, #a29bfe 100%);
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 100%);

    /* 中性色 */
    --text-color: #2d3436;
    --text-light: #636e72;
    --text-lighter: #b2bec3;
    --bg-color: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-card: #ffffff;
    --border-color: #e9ecef;
    --shadow-color: rgba(0, 0, 0, 0.08);
    --shadow-hover: rgba(108, 92, 231, 0.15);

    /* 布局 */
    --header-height: 4rem;
    --container-width: 1200px;
    --border-radius: 16px;
    --border-radius-sm: 8px;
    --border-radius-lg: 24px;

    /* 过渡 */
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 深色主题 */
[data-theme="dark"] {
    --text-color: #f0f0f0;
    --text-light: #b0b0b0;
    --text-lighter: #707070;
    --bg-color: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: #1a1a2e;
    --border-color: #2a2a3e;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --shadow-hover: rgba(108, 92, 231, 0.25);
    --gradient-hero: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
}

/* ==============================
   基础重置
   ============================== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.7;
    transition: background-color var(--transition-slow), color var(--transition-slow);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

ul {
    list-style: none;
}

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

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

button {
    cursor: pointer;
    border: none;
    outline: none;
    background: none;
    font-family: inherit;
}

input,
textarea {
    font-family: inherit;
    outline: none;
    border: none;
}

/* ==============================
   容器
   ============================== */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 6rem 0;
    position: relative;
}

/* ==============================
   通用组件
   ============================== */
.section__header {
    text-align: center;
    margin-bottom: 4rem;
}

.section__tag {
    display: inline-block;
    padding: 0.35rem 1rem;
    background: var(--gradient-primary);
    color: #fff;
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 50px;
    letter-spacing: 1px;
    text-transform: uppercase;
    margin-bottom: 1rem;
}

.section__title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section__subtitle {
    color: var(--text-light);
    font-size: 1.1rem;
    max-width: 500px;
    margin: 0 auto;
}

.highlight {
    color: var(--primary-color);
}

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.9rem 2rem;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 50px;
    transition: all var(--transition);
    cursor: pointer;
    border: 2px solid transparent;
}

.btn i {
    font-size: 1rem;
}

.btn--primary {
    background: var(--gradient-primary);
    color: #fff;
    box-shadow: 0 4px 15px var(--shadow-hover);
}

.btn--primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px var(--shadow-hover);
}

.btn--outline {
    background: transparent;
    color: var(--text-color);
    border-color: var(--border-color);
}

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

/* ==============================
   导航栏
   ============================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: transparent;
    transition: all var(--transition);
}

.header.scrolled {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 1px 30px var(--shadow-color);
}

[data-theme="dark"] .header.scrolled {
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
}

.nav {
    height: var(--header-height);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav__logo {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-weight: 700;
}

.nav__logo-icon {
    font-size: 1.3rem;
    color: var(--primary-color);
    font-weight: 800;
}

.nav__logo-text {
    font-size: 1.25rem;
    color: var(--text-color);
}

.nav__menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav__list {
    display: flex;
    gap: 2.5rem;
}

.nav__link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-light);
    transition: color var(--transition);
    position: relative;
}

.nav__link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: width var(--transition);
    border-radius: 1px;
}

.nav__link:hover {
    color: var(--text-color);
}

.nav__link:hover::after,
.nav__link.active-link::after {
    width: 100%;
}

.nav__link.active-link {
    color: var(--primary-color);
}

.nav__actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* 主题切换按钮 */
.theme-toggle {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--bg-secondary);
    color: var(--text-color);
    font-size: 1.1rem;
    transition: all var(--transition);
    position: relative;
}

.theme-toggle:hover {
    background: var(--primary-color);
    color: #fff;
    transform: rotate(30deg);
}

/* Auto 模式指示器小圆点 */
.theme-toggle[data-mode="auto"]::after {
    content: '';
    position: absolute;
    bottom: 2px;
    right: 2px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--primary-color);
    border: 2px solid var(--bg-color);
    animation: pulse 2s ease-in-out infinite;
}

.nav__toggle,
.nav__close {
    display: none;
}

/* ==============================
   Hero 区域
   ============================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding-top: var(--header-height);
}

.hero__bg {
    position: absolute;
    inset: 0;
    background: var(--gradient-hero);
    opacity: 0.05;
    z-index: -1;
}

.hero__bg::before {
    content: '';
    position: absolute;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    background: var(--primary-color);
    opacity: 0.05;
    top: -200px;
    right: -200px;
    animation: float 20s ease-in-out infinite;
}

.hero__bg::after {
    content: '';
    position: absolute;
    width: 400px;
    height: 400px;
    border-radius: 50%;
    background: var(--primary-dark);
    opacity: 0.05;
    bottom: -100px;
    left: -100px;
    animation: float 25s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(50px, -50px) scale(1.1); }
    66% { transform: translate(-30px, 30px) scale(0.9); }
}

.hero__container {
    width: 100%;
}

.hero__content {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 2rem;
}

.hero__data {
    max-width: 700px;
}

.hero__greeting {
    display: inline-block;
    font-size: 1.1rem;
    color: var(--primary-color);
    font-weight: 500;
    margin-bottom: 1rem;
    animation: fadeInUp 0.6s ease;
}

.hero__title {
    font-size: 4.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 0.5rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 0.6s ease 0.1s both;
}

.hero__subtitle {
    font-size: 1.4rem;
    color: var(--text-light);
    font-weight: 500;
    margin-bottom: 1.2rem;
    animation: fadeInUp 0.6s ease 0.2s both;
}

.hero__description {
    font-size: 1.05rem;
    color: var(--text-light);
    line-height: 1.8;
    margin-bottom: 2rem;
    animation: fadeInUp 0.6s ease 0.3s both;
}

.hero__buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 0.6s ease 0.4s both;
}

.hero__social {
    display: flex;
    gap: 1.2rem;
    animation: fadeInUp 0.6s ease 0.5s both;
}

.hero__social-link {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--bg-secondary);
    color: var(--text-light);
    font-size: 1.2rem;
    transition: all var(--transition);
}

.hero__social-link:hover {
    background: var(--gradient-primary);
    color: #fff;
    transform: translateY(-4px);
}

.hero__scroll {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    animation: fadeInUp 0.6s ease 0.6s both;
}

.hero__scroll-link {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.3rem;
    color: var(--text-lighter);
    font-size: 0.8rem;
    transition: color var(--transition);
}

.hero__scroll-link:hover {
    color: var(--primary-color);
}

.hero__scroll-link i {
    animation: bounceDown 2s ease-in-out infinite;
}

@keyframes bounceDown {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(8px); }
    60% { transform: translateY(4px); }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ==============================
   博客文章区域
   ============================== */
.blog {
    background: var(--bg-secondary);
    transition: background-color var(--transition-slow);
}

.blog__filters {
    display: flex;
    justify-content: center;
    gap: 0.8rem;
    flex-wrap: wrap;
    margin-bottom: 3rem;
}

.blog__filter-btn {
    padding: 0.6rem 1.5rem;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-light);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
}

.blog__filter-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.blog__filter-btn.active {
    background: var(--gradient-primary);
    color: #fff;
    border-color: transparent;
    box-shadow: 0 4px 15px var(--shadow-hover);
}

.blog__grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

/* 文章卡片 */
.blog__card {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all var(--transition);
    animation: cardAppear 0.6s ease both;
}

.blog__card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px var(--shadow-hover);
    border-color: transparent;
}

.blog__card--external .blog__card-read {
    color: var(--text-lighter);
    font-weight: 400;
}

.blog__card--external .blog__card-read i {
    color: var(--primary-light);
}

.blog__card--external:hover .blog__card-read {
    color: var(--primary-color);
}

@keyframes cardAppear {
    from {
        opacity: 0;
        transform: translateY(40px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.blog__card-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    display: block;
}

.blog__card-image-placeholder {
    width: 100%;
    height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: #fff;
    position: relative;
    overflow: hidden;
}

.blog__card-image-placeholder .card-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.blog__card-image-placeholder i {
    position: relative;
    z-index: 1;
    filter: drop-shadow(0 2px 8px rgba(0,0,0,0.2));
}

.blog__card-body {
    padding: 1.5rem;
}

.blog__card-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 0.8rem;
    font-size: 0.8rem;
    color: var(--text-lighter);
}

.blog__card-category {
    display: inline-block;
    padding: 0.2rem 0.8rem;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.blog__card-category.tech { background: rgba(108, 92, 231, 0.1); color: #6c5ce7; }
.blog__card-category.life { background: rgba(0, 206, 201, 0.1); color: #00cec9; }
.blog__card-category.tutorial { background: rgba(253, 203, 110, 0.15); color: #e17055; }
.blog__card-category.notes { background: rgba(116, 185, 255, 0.1); color: #0984e3; }

.blog__card-date {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.blog__card-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 0.6rem;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.blog__card-excerpt {
    font-size: 0.9rem;
    color: var(--text-light);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    margin-bottom: 1rem;
    line-height: 1.6;
}

.blog__card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.blog__card-author {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: 0.85rem;
    font-weight: 500;
}

.blog__card-author img,
.blog__card-author-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    object-fit: cover;
}

.blog__card-author-avatar {
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 0.8rem;
    font-weight: 700;
}

.blog__card-read {
    font-size: 0.85rem;
    color: var(--primary-color);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.3rem;
    transition: gap var(--transition);
}

.blog__card-read:hover {
    gap: 0.6rem;
}

.blog__more {
    text-align: center;
}

/* ==============================
   分类区域
   ============================== */
.categories__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 2rem;
}

.category__card {
    background: var(--bg-card);
    border-radius: var(--border-radius);
    padding: 2.5rem 2rem;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: all var(--transition);
    cursor: pointer;
}

.category__card:hover {
    transform: translateY(-6px);
    box-shadow: 0 15px 30px var(--shadow-hover);
    border-color: transparent;
}

.category__icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 16px;
    font-size: 1.6rem;
    color: #fff;
}

.category__card[data-category="tech"] .category__icon { background: linear-gradient(135deg, #6c5ce7, #a29bfe); }
.category__card[data-category="life"] .category__icon { background: linear-gradient(135deg, #00cec9, #81ecec); }
.category__card[data-category="tutorial"] .category__icon { background: linear-gradient(135deg, #e17055, #fab1a0); }
.category__card[data-category="notes"] .category__icon { background: linear-gradient(135deg, #0984e3, #74b9ff); }

.category__title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 0.3rem;
}

.category__desc {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.category__count {
    font-size: 0.85rem;
    color: var(--text-lighter);
    font-weight: 500;
}

/* ==============================
   关于我
   ============================== */
.about {
    background: var(--bg-secondary);
    transition: background-color var(--transition-slow);
}

.about__content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 4rem;
    align-items: center;
}

.about__image-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.about__image {
    width: 100%;
    max-width: 320px;
    aspect-ratio: 1;
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    position: relative;
}

.about__image-placeholder {
    width: 100%;
    height: 100%;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 5rem;
    color: rgba(255,255,255,0.8);
}

.about__image-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.about__status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--text-light);
}

.about__status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #00b894;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

.about__title {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 1.2rem;
}

.about__description {
    color: var(--text-light);
    margin-bottom: 1rem;
    line-height: 1.8;
}

.about__info {
    display: flex;
    gap: 2.5rem;
    margin: 2rem 0;
}

.about__info-item {
    text-align: center;
}

.about__info-number {
    display: block;
    font-size: 2rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.about__info-text {
    font-size: 0.85rem;
    color: var(--text-light);
    font-weight: 500;
}

.about__skills {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
}

.about__skill-tag {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.4rem 1rem;
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 600;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-light);
    transition: all var(--transition);
}

.about__skill-tag:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
}

/* ==============================
   联系我
   ============================== */
.contact__content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 3rem;
    align-items: start;
}

.contact__info {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.contact__info-card {
    display: flex;
    align-items: center;
    gap: 1.2rem;
    padding: 1.2rem 1.5rem;
    background: var(--bg-card);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
}

.contact__info-card:hover {
    border-color: var(--primary-color);
    transform: translateX(4px);
}

.contact__info-card i {
    font-size: 1.3rem;
    color: var(--primary-color);
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    background: rgba(108, 92, 231, 0.1);
}

.contact__info-card h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.2rem;
}

.contact__info-card p {
    font-size: 0.85rem;
    color: var(--text-light);
}

/* 表单 */
.contact__form {
    background: var(--bg-card);
    padding: 2.5rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
}

.contact__form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.contact__form-group {
    position: relative;
    margin-bottom: 1.5rem;
}

.contact__form-input {
    width: 100%;
    padding: 1rem 1.2rem;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    background: transparent;
    color: var(--text-color);
    font-size: 0.95rem;
    transition: all var(--transition);
}

.contact__form-input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(108, 92, 231, 0.1);
}

.contact__form-textarea {
    min-height: 140px;
    resize: vertical;
}

.contact__form-label {
    position: absolute;
    left: 1.2rem;
    top: 1rem;
    color: var(--text-lighter);
    font-size: 0.95rem;
    pointer-events: none;
    transition: all var(--transition);
    background: var(--bg-card);
    padding: 0 0.3rem;
}

.contact__form-input:focus ~ .contact__form-label,
.contact__form-input:not(:placeholder-shown) ~ .contact__form-label {
    top: -0.6rem;
    left: 0.8rem;
    font-size: 0.8rem;
    color: var(--primary-color);
}

.contact__form-btn {
    width: 100%;
    justify-content: center;
    padding: 1rem;
    font-size: 1rem;
}

/* ==============================
   页脚
   ============================== */
.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 4rem 0 2rem;
    transition: background-color var(--transition-slow);
}

.footer__content {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 4rem;
    margin-bottom: 3rem;
}

.footer__description {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-top: 1rem;
    max-width: 300px;
}

.footer__links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.footer__links-group {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.footer__links-title {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.footer__links-group a {
    font-size: 0.9rem;
    color: var(--text-light);
    transition: color var(--transition);
}

.footer__links-group a:hover {
    color: var(--primary-color);
}

.footer__social {
    display: flex;
    gap: 0.8rem;
}

.footer__social-link {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--bg-card);
    color: var(--text-light);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
}

.footer__social-link:hover {
    background: var(--gradient-primary);
    color: #fff;
    border-color: transparent;
    transform: translateY(-3px);
}

.footer__bottom {
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    color: var(--text-lighter);
}

/* ==============================
   回到顶部
   ============================== */
.scrollup {
    position: fixed;
    bottom: -100px;
    right: 2rem;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    color: #fff;
    border-radius: 50%;
    font-size: 1.1rem;
    box-shadow: 0 4px 15px var(--shadow-hover);
    transition: all var(--transition);
    z-index: 100;
    opacity: 0;
    visibility: hidden;
}

.scrollup.show {
    bottom: 2rem;
    opacity: 1;
    visibility: visible;
}

.scrollup:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px var(--shadow-hover);
}

/* ==============================
   响应式设计
   ============================== */
@media screen and (max-width: 1024px) {
    .about__content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .about__image-wrapper {
        margin: 0 auto;
    }

    .about__info {
        justify-content: center;
    }

    .about__skills {
        justify-content: center;
    }

    .contact__content {
        grid-template-columns: 1fr;
    }
}

@media screen and (max-width: 768px) {
    .section {
        padding: 4rem 0;
    }

    .section__title {
        font-size: 2rem;
    }

    .hero__title {
        font-size: 3rem;
    }

    .hero__subtitle {
        font-size: 1.1rem;
    }

    .blog__grid {
        grid-template-columns: 1fr;
    }

    .categories__grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer__content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .footer__links {
        grid-template-columns: repeat(2, 1fr);
    }

    .contact__form {
        padding: 1.5rem;
    }

    .contact__form-row {
        grid-template-columns: 1fr;
    }

    /* 移动端导航 */
    .nav__menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        flex-direction: column;
        background: var(--bg-card);
        padding: 6rem 2rem 2rem;
        border-left: 1px solid var(--border-color);
        transition: right var(--transition);
        gap: 2rem;
        justify-content: flex-start;
        align-items: flex-start;
        box-shadow: -10px 0 30px var(--shadow-color);
    }

    .nav__menu.show {
        right: 0;
    }

    .nav__list {
        flex-direction: column;
        gap: 1.5rem;
    }

    .nav__toggle {
        display: block;
        font-size: 1.3rem;
        color: var(--text-color);
    }

    .nav__close {
        display: block;
        position: absolute;
        top: 1.5rem;
        right: 1.5rem;
        font-size: 1.3rem;
        color: var(--text-color);
    }

    .nav__actions {
        width: 100%;
        justify-content: space-between;
        padding-top: 1rem;
        border-top: 1px solid var(--border-color);
    }
}

@media screen and (max-width: 480px) {
    .hero__title {
        font-size: 2.2rem;
    }

    .categories__grid {
        grid-template-columns: 1fr;
    }

    .about__info {
        flex-wrap: wrap;
        gap: 1.5rem;
    }

    .footer__bottom {
        flex-direction: column;
        text-align: center;
        gap: 0.5rem;
    }
}

/* ==============================
   滚动条美化
   ============================== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--text-lighter);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-color);
}

/* ==============================
   选择文本样式
   ============================== */
::selection {
    background: var(--primary-color);
    color: #fff;
}

/* ==============================
   文章卡片链接
   ============================== */
.blog__card-link {
    text-decoration: none;
    color: inherit;
    display: block;
    transition: all var(--transition);
}

.blog__card-link:hover {
    text-decoration: none;
}

.blog__card-link .blog__card {
    cursor: pointer;
}

/* ==============================
   文章详情页 - Hero
   ============================== */
.article-hero {
    padding: 8rem 0 3rem;
    background: var(--bg-secondary);
    position: relative;
    overflow: hidden;
    transition: background-color var(--transition-slow);
}

.article-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-hero);
    opacity: 0.04;
    z-index: 0;
}

.article-hero__content {
    position: relative;
    z-index: 1;
    max-width: 800px;
    margin: 0 auto;
}

.article-hero__back {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-light);
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 2rem;
    transition: color var(--transition);
}

.article-hero__back:hover {
    color: var(--primary-color);
}

.article-hero__meta {
    display: flex;
    align-items: center;
    gap: 1.2rem;
    flex-wrap: wrap;
    margin-bottom: 1.2rem;
    font-size: 0.85rem;
    color: var(--text-light);
}

.article-hero__date,
.article-hero__readtime {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.article-hero__title {
    font-size: 2.8rem;
    font-weight: 800;
    line-height: 1.3;
    color: var(--text-color);
}

/* ==============================
   文章详情页 - 内容
   ============================== */
.article-content {
    padding: 3rem 0 5rem;
    background: var(--bg-color);
    transition: background-color var(--transition-slow);
}

.article-content__wrapper {
    max-width: 800px;
    margin: 0 auto;
}

.article-content__body {
    font-size: 1.05rem;
    line-height: 1.9;
    color: var(--text-color);
}

.article-content__body p {
    margin-bottom: 1.5rem;
}

.article-content__body h2 {
    font-size: 1.8rem;
    font-weight: 700;
    margin: 2.5rem 0 1rem;
    color: var(--text-color);
}

.article-content__body h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin: 2rem 0 0.8rem;
    color: var(--text-color);
}

.article-content__body ul,
.article-content__body ol {
    margin: 1rem 0 1.5rem 1.5rem;
}

.article-content__body li {
    margin-bottom: 0.5rem;
}

.article-content__body blockquote {
    border-left: 4px solid var(--primary-color);
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    background: var(--bg-secondary);
    border-radius: 0 var(--border-radius-sm) var(--border-radius-sm) 0;
    color: var(--text-light);
    font-style: italic;
}

.article-content__body code {
    background: var(--bg-secondary);
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-size: 0.9em;
    font-family: 'Consolas', 'Monaco', monospace;
}

.article-content__body pre {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: var(--border-radius-sm);
    overflow-x: auto;
    margin: 1.5rem 0;
    border: 1px solid var(--border-color);
}

.article-content__body pre code {
    background: none;
    padding: 0;
}

.article-content__body img {
    border-radius: var(--border-radius-sm);
    margin: 1.5rem 0;
    max-width: 100%;
}

.article-content__body a {
    color: var(--primary-color);
    text-decoration: underline;
    text-underline-offset: 2px;
}

.article-content__body a:hover {
    color: var(--primary-dark);
}

.article__empty {
    text-align: center;
    padding: 4rem 0;
    color: var(--text-light);
    font-size: 1.1rem;
}

/* ==============================
   文章导航（上下篇）
   ============================== */
.article-nav {
    display: flex;
    justify-content: space-between;
    gap: 1.5rem;
    margin-top: 4rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
}

.article-nav__link {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    text-decoration: none;
    color: var(--text-color);
    transition: all var(--transition);
    background: var(--bg-card);
    max-width: 50%;
}

.article-nav__link:hover {
    border-color: var(--primary-color);
    transform: translateY(-3px);
    box-shadow: 0 8px 25px var(--shadow-hover);
}

.article-nav__link--next {
    text-align: right;
    margin-left: auto;
}

.article-nav__direction {
    font-size: 0.85rem;
    color: var(--primary-color);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.article-nav__link--next .article-nav__direction {
    justify-content: flex-end;
}

.article-nav__title {
    font-size: 1rem;
    font-weight: 600;
    display: -webkit-box;
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ==============================
   响应式 - 文章页
   ============================== */
@media screen and (max-width: 768px) {
    .article-hero {
        padding: 6rem 0 2rem;
    }

    .article-hero__title {
        font-size: 1.8rem;
    }

    .article-content__body {
        font-size: 1rem;
    }

    .article-nav {
        flex-direction: column;
    }

    .article-nav__link {
        max-width: 100%;
    }

    .article-nav__link--next {
        text-align: left;
        margin-left: 0;
    }

    .article-nav__link--next .article-nav__direction {
        justify-content: flex-start;
    }
}