:root {
    --primary: #1a9fff;
    --primary-light: #66c0f4;
    --primary-dark: #0d8ae3;
    --accent: #26d0ff;
    --dark: #171a21;
    --panel: #1b2838;
    --panel-2: #2a3f5a;
    --light: #e5e5e5;
    --muted: #8f98a0;
    --text: #c6d4df;
    --success: #5ba32b;
    --warning: #e5ae30;
    --danger: #d63626;
    --grad-primary: linear-gradient(135deg, #1a9fff 0%, #26d0ff 100%);
    --grad-hero: radial-gradient(circle at 20% 20%, rgba(26, 159, 255, 0.25), transparent 45%),
                 radial-gradient(circle at 80% 30%, rgba(38, 208, 255, 0.18), transparent 40%),
                 radial-gradient(circle at 50% 90%, rgba(102, 192, 244, 0.15), transparent 50%);
    --glass: rgba(42, 71, 94, 0.35);
    --glass-border: rgba(102, 192, 244, 0.15);
    --glow: 0 0 30px rgba(26, 159, 255, 0.35);
    --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.35);
    --radius: 14px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Motiva Sans", "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--panel);
    background-image:
        radial-gradient(circle at 15% -10%, rgba(26, 159, 255, 0.08), transparent 40%),
        radial-gradient(circle at 85% 5%, rgba(38, 208, 255, 0.06), transparent 35%);
    background-attachment: fixed;
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== 导航栏 ===== */
header {
    background-color: rgba(23, 26, 33, 0.72);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    padding: 14px 0;
    box-shadow: 0 1px 0 rgba(102, 192, 244, 0.12), 0 6px 24px rgba(0, 0, 0, 0.35);
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
}

.logo a {
    height: 40px;
    display: flex;
    align-items: center;
}

.logo img {
    height: 40px;
    margin-right: 12px;
    filter: drop-shadow(0 0 8px rgba(26, 159, 255, 0.4));
}

.logo h1,
.logo .logo-title {
    font-size: 24px;
    font-weight: 700;
    background: var(--grad-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: var(--primary-light);
}

.nav-links {
    display: flex;
    list-style: none;
    align-items: center;
}

.nav-links li {
    margin-left: 30px;
}

.nav-links a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
    position: relative;
}

.nav-links a:not(.btn)::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 0;
    height: 2px;
    background: var(--grad-primary);
    transition: width 0.3s;
    border-radius: 2px;
}

.nav-links a:not(.btn):hover::after {
    width: 100%;
}

.nav-links a:hover {
    color: var(--primary-light);
}

.btn {
    display: inline-block;
    padding: 11px 24px;
    background: var(--grad-primary);
    color: #fff;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 14px rgba(26, 159, 255, 0.35);
}

.nav-links a.btn:hover {
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(26, 159, 255, 0.5);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(26, 159, 255, 0.5);
}

/* ===== 右侧固定导航 ===== */
.side-nav {
    position: fixed;
    right: 30px;
    top: 50%;
    transform: translateY(-50%);
    z-index: 99;
    background: rgba(23, 26, 33, 0.6);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 14px 10px;
    border-radius: 40px;
    border: 1px solid var(--glass-border);
    box-shadow: var(--shadow-card);
}

.side-nav ul {
    list-style: none;
}

.side-nav li {
    margin: 6px 0;
}

.side-nav a {
    color: var(--muted);
    text-decoration: none;
    font-weight: 500;
    font-size: 14px;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    padding: 8px 14px;
    border-radius: 30px;
}

.side-nav a:hover {
    color: var(--primary-light);
    background: rgba(26, 159, 255, 0.12);
}

.side-nav a.active {
    color: #fff;
    background: var(--grad-primary);
    box-shadow: var(--glow);
}

/* ===== 汉堡菜单按钮 ===== */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 21px;
    cursor: pointer;
    z-index: 1000;
}

.menu-toggle span {
    display: block;
    height: 3px;
    width: 100%;
    background-color: #fff;
    border-radius: 3px;
    transition: all 0.3s ease;
}

/* ===== Hero ===== */
.hero {
    background:
        var(--grad-hero),
        linear-gradient(160deg, #0f1620 0%, #1b2838 55%, #16212e 100%);
    background-size: cover;
    background-position: center;
    min-height: 560px;
    display: flex;
    align-items: center;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(102, 192, 244, 0.06) 1px, transparent 1px),
        linear-gradient(90deg, rgba(102, 192, 244, 0.06) 1px, transparent 1px);
    background-size: 46px 46px;
    mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
    -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
    pointer-events: none;
}

.hero::after {
    content: "";
    position: absolute;
    width: 520px;
    height: 520px;
    left: 50%;
    top: 45%;
    transform: translate(-50%, -50%);
    background: radial-gradient(circle, rgba(26, 159, 255, 0.35), transparent 65%);
    filter: blur(30px);
    animation: heroPulse 6s ease-in-out infinite;
    pointer-events: none;
}

@keyframes heroPulse {
    0%, 100% { opacity: 0.7; transform: translate(-50%, -50%) scale(1); }
    50% { opacity: 1; transform: translate(-50%, -50%) scale(1.12); }
}

.hero-content {
    max-width: 820px;
    margin: 0 auto;
    padding: 20px;
    position: relative;
    z-index: 2;
}

.hero h1,
.hero h2 {
    font-size: 52px;
    line-height: 1.15;
    margin-bottom: 22px;
    color: #fff;
    background: linear-gradient(180deg, #ffffff 0%, #b9dcff 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: 0.5px;
}

.hero p {
    font-size: 20px;
    margin-bottom: 34px;
    color: #b8d0e0;
    max-width: 760px;
    margin-left: auto;
    margin-right: auto;
}

.hero .btn {
    padding: 14px 38px;
    font-size: 17px;
}

/* ===== 通用区块标题 ===== */
.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title h2 {
    font-size: 36px;
    color: #fff;
    margin-bottom: 15px;
    position: relative;
    display: inline-block;
}

.section-title h2::after {
    content: "";
    position: absolute;
    left: 50%;
    bottom: -12px;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    border-radius: 3px;
    background: var(--grad-primary);
}

.section-title p {
    max-width: 700px;
    margin: 18px auto 0;
    color: var(--muted);
}

/* ===== 特性部分 ===== */
.features {
    padding: 90px 0;
    background-color: #22344c;
    position: relative;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 26px;
}

.feature-card {
    background: var(--glass);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    padding: 34px 30px;
    border-radius: var(--radius);
    border: 1px solid var(--glass-border);
    transition: transform 0.35s, box-shadow 0.35s, border-color 0.35s;
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--grad-primary);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.35s;
}

.feature-card:hover {
    transform: translateY(-10px);
    border-color: rgba(102, 192, 244, 0.4);
    box-shadow: var(--shadow-card), 0 0 24px rgba(26, 159, 255, 0.2);
}

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-icon {
    font-size: 34px;
    margin-bottom: 20px;
    width: 68px;
    height: 68px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 16px;
    background: rgba(26, 159, 255, 0.12);
    border: 1px solid var(--glass-border);
    transition: transform 0.35s;
}

.feature-card:hover .feature-icon {
    transform: scale(1.08) rotate(-4deg);
}

.feature-card h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: #fff;
}

/* ===== 如何使用 ===== */
.how-to-use {
    padding: 90px 0;
    background-color: var(--panel);
}

.steps {
    max-width: 800px;
    margin: 0 auto;
    position: relative;
}

.steps::before {
    content: "";
    position: absolute;
    left: 19px;
    top: 10px;
    bottom: 40px;
    width: 2px;
    background: linear-gradient(var(--primary), transparent);
    opacity: 0.4;
}

.step {
    display: flex;
    margin-bottom: 40px;
    align-items: flex-start;
    position: relative;
}

.step-number {
    background: var(--grad-primary);
    color: #fff;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    margin-right: 22px;
    flex-shrink: 0;
    box-shadow: 0 0 0 6px rgba(26, 159, 255, 0.1), var(--glow);
    z-index: 1;
}

.step-content h3 {
    font-size: 22px;
    margin-bottom: 10px;
    color: #fff;
}

/* ===== 价格部分 ===== */
.pricing {
    padding: 90px 0;
    background-color: #22344c;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
    margin-top: 50px;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.pricing-card {
    background: var(--glass);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-radius: var(--radius);
    border: 1px solid var(--glass-border);
    overflow: hidden;
    transition: transform 0.35s, box-shadow 0.35s;
    position: relative;
}

.pricing-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-card), 0 0 26px rgba(26, 159, 255, 0.22);
}

.pricing-card.featured {
    border-color: var(--primary);
    box-shadow: 0 0 0 1px var(--primary), 0 12px 40px rgba(26, 159, 255, 0.25);
}

.pricing-badge {
    position: absolute;
    top: 16px;
    right: -34px;
    background: var(--grad-primary);
    color: #fff;
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 1px;
    padding: 5px 40px;
    transform: rotate(45deg);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
}

.pricing-header {
    padding: 28px 20px;
    text-align: center;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.25), rgba(0, 0, 0, 0.05));
}

.pricing-header h3 {
    font-size: 24px;
    color: #fff;
    margin-bottom: 14px;
}

.price {
    font-size: 34px;
    font-weight: bold;
    color: var(--primary-light);
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 22px;
    flex-wrap: wrap;
}

.price span {
    font-size: 15px;
    color: var(--muted);
    font-weight: 500;
    margin-left: 2px;
}

.price-img {
    height: 44px;
    width: auto;
    max-width: 100%;
    display: block;
    margin: 0 auto;
}

.pricing-body {
    padding: 30px;
}

.pricing-features {
    list-style: none;
    margin-bottom: 30px;
}

.pricing-features li {
    margin-bottom: 12px;
    position: relative;
    padding-left: 28px;
    color: var(--text);
}

.pricing-features li:before {
    content: "✓";
    color: #fff;
    background: var(--success);
    width: 18px;
    height: 18px;
    font-size: 11px;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    position: absolute;
    left: 0;
    top: 4px;
}

.pricing-body .btn {
    width: 100%;
    text-align: center;
}

/* ===== 常见问题 ===== */
.faq {
    padding: 90px 0;
    background-color: var(--panel);
}

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

.accordion-item {
    margin-bottom: 15px;
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    overflow: hidden;
    background: var(--glass);
    transition: border-color 0.3s;
}

.accordion-item.active {
    border-color: rgba(102, 192, 244, 0.4);
}

.accordion-header {
    padding: 18px 22px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background 0.3s;
}

.accordion-header:hover {
    background: rgba(26, 159, 255, 0.06);
}

.accordion-header h3 {
    color: #fff;
    font-size: 18px;
}

.accordion-header span {
    color: var(--primary-light);
    font-size: 24px;
    font-weight: 300;
    transition: transform 0.3s;
    flex-shrink: 0;
    margin-left: 16px;
}

.accordion-item.active .accordion-header span {
    transform: rotate(180deg);
}

.accordion-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.4s ease;
    padding: 0 22px;
    color: var(--text);
}

.accordion-item.active .accordion-content {
    max-height: 320px;
    padding: 4px 22px 22px;
}

/* ===== 页脚 ===== */
footer {
    background-color: var(--dark);
    padding: 55px 0 22px;
    border-top: 1px solid rgba(102, 192, 244, 0.1);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.footer-column h3 {
    color: #fff;
    margin-bottom: 20px;
    font-size: 18px;
    position: relative;
    padding-bottom: 10px;
}

.footer-column h3::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 30px;
    height: 2px;
    background: var(--grad-primary);
    border-radius: 2px;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    color: var(--muted);
    text-decoration: none;
    transition: all 0.3s;
}

.footer-links a:hover {
    color: var(--primary-light);
    padding-left: 4px;
}

.copyright {
    text-align: center;
    padding-top: 22px;
    border-top: 1px solid var(--panel-2);
    color: var(--muted);
    font-size: 14px;
}

/* ===== 滚动进场动画 ===== */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
    will-change: opacity, transform;
}

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

/* ===== 文章列表页 ===== */
.articles-section {
    padding: 80px 0;
    background-color: var(--panel);
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.article-card {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: transform 0.35s, box-shadow 0.35s;
}

.article-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-card);
}

.article-image {
    height: 200px;
    background-size: cover;
    background-position: center;
}

.article-content {
    padding: 25px;
}

.article-meta {
    display: flex;
    justify-content: space-between;
    color: var(--muted);
    font-size: 14px;
    margin-bottom: 15px;
}

.article-card h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: #fff;
}

.article-excerpt {
    color: #b8b6b4;
    margin-bottom: 20px;
}

.read-more {
    color: var(--primary-light);
    text-decoration: none;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
}

.read-more:after {
    content: "→";
    margin-left: 5px;
    transition: margin 0.3s;
}

.read-more:hover:after {
    margin-left: 10px;
}

.pagination {
    display: flex;
    justify-content: center;
    margin-top: 50px;
}

.page-numbers {
    display: flex;
    list-style: none;
}

.page-numbers li {
    margin: 0 5px;
}

.page-numbers a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--glass);
    color: var(--text);
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.3s;
}

.page-numbers a:hover,
.page-numbers a.active,
.page-numbers a.page-num-current {
    background: var(--grad-primary);
    color: #fff;
}

/* ===== 文章详情页 ===== */
.article-detail-section {
    padding: 80px 0;
    background-color: var(--panel);
}

.article-container {
    max-width: 800px;
    margin: 0 auto;
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    overflow: hidden;
}

.article-header-image {
    height: 400px;
    background-size: cover;
    background-position: center;
}

.article-main-content {
    padding: 40px;
}

.article-container .article-meta {
    margin-bottom: 30px;
}

.article-tags {
    display: flex;
}

.article-tags span {
    margin-left: 10px;
    padding: 4px 12px;
    background-color: rgba(26, 159, 255, 0.12);
    color: var(--primary-light);
    border-radius: 20px;
    font-size: 12px;
}

.article-title {
    font-size: 32px;
    margin-bottom: 20px;
    color: #fff;
    line-height: 1.3;
}

.article-content {
    color: var(--text);
    line-height: 1.9;
}

.article-content h2,
.article-content h3,
.article-content h4 {
    color: #fff;
    margin: 30px 0 15px;
}

.article-content h2 {
    font-size: 24px;
    border-bottom: 1px solid var(--panel-2);
    padding-bottom: 10px;
}

.article-content h3 {
    font-size: 20px;
}

.article-content p {
    margin-bottom: 18px;
}

.article-content ul,
.article-content ol {
    margin-bottom: 20px;
    padding-left: 20px;
}

.article-content li {
    margin-bottom: 10px;
}

.article-content a {
    color: var(--primary-light);
    word-break: break-all;
}

.article-content img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 20px 0;
    border: 1px solid var(--panel-2);
}

.article-navigation {
    display: flex;
    justify-content: space-between;
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid var(--panel-2);
}

.nav-previous,
.nav-next {
    flex: 1;
}

.nav-next {
    text-align: right;
}

.nav-label {
    color: var(--muted);
    font-size: 14px;
    margin-bottom: 5px;
}

.nav-title {
    color: var(--primary-light);
    font-weight: 600;
    text-decoration: none;
}

.related-articles {
    margin-top: 80px;
}

.related-title {
    font-size: 24px;
    color: #fff;
    margin-bottom: 30px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--panel-2);
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.related-article {
    background: rgba(42, 71, 94, 0.3);
    padding: 20px;
    border-radius: 10px;
    transition: transform 0.3s;
}

.related-article:hover {
    transform: translateY(-5px);
}

.related-article h3 {
    font-size: 16px;
    color: #fff;
    margin-bottom: 10px;
}

.related-article p {
    color: var(--muted);
    font-size: 14px;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .menu-toggle {
        display: flex;
    }

    .nav-links {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background-color: rgba(23, 26, 33, 0.97);
        backdrop-filter: blur(10px);
        -webkit-backdrop-filter: blur(10px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        z-index: 999;
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links li {
        margin: 15px 0;
    }

    .nav-links a {
        font-size: 20px;
    }

    .menu-toggle.active span:first-child {
        transform: rotate(45deg) translate(6px, 6px);
    }

    .menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .menu-toggle.active span:last-child {
        transform: rotate(-45deg) translate(6px, -6px);
    }

    .side-nav {
        display: none;
    }

    .hero h1,
    .hero h2 {
        font-size: 34px;
    }

    .hero p {
        font-size: 17px;
    }

    .section-title h2 {
        font-size: 28px;
    }

    .article-main-content {
        padding: 28px 22px;
    }
}