/* 全局样式 */
:root {
    --bg: #ffffff;
    --bg-muted: #f5f5f7;
    --text: #0a0a0a;
    --text-muted: #4b5563;
    --text-subtle: #6b7280;
    --border: #e5e7eb;
    --border-strong: #d1d5db;
    --brand: #2196F3;
    --brand-strong: #1976D2;
    --brand-soft: #E3F2FD;
    --brand-ring: rgba(33, 150, 243, 0.22);
    --radius-card: 16px;
    --radius-pill: 999px;
    --shadow-card: 0 1px 2px rgba(15, 23, 42, 0.04), 0 4px 12px rgba(15, 23, 42, 0.04);
    --shadow-card-hover: 0 1px 2px rgba(15, 23, 42, 0.06), 0 8px 24px rgba(33, 150, 243, 0.10);
    --font-display: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    color-scheme: light;
}

/* Dark theme — applied via data-theme attribute set by inline head script.
   All site colors flow from these tokens; pages that use only var(--*) auto-flip.  */
[data-theme="dark"] {
    --bg: #0d0d0f;
    --bg-muted: #18181b;
    --text: #ededed;
    --text-muted: #b1b1b4;
    --text-subtle: #8a8a8e;
    --border: #2a2a2e;
    --border-strong: #3a3a3f;
    --brand: #5aaeff;
    --brand-strong: #82c2ff;
    --brand-soft: #14283d;
    --brand-ring: rgba(90, 174, 255, 0.32);
    --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.45);
    --shadow-card-hover: 0 1px 2px rgba(0, 0, 0, 0.5), 0 8px 24px rgba(90, 174, 255, 0.18);
    color-scheme: dark;
}

:focus-visible {
    outline: 2px solid var(--brand-ring);
    outline-offset: 2px;
    border-radius: 4px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-display);
    line-height: 1.6;
    color: var(--text);
    background-color: var(--bg);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

/* 导航栏 */
.navbar {
    background: var(--bg);
    color: var(--text);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    display: flex;
    align-items: center;
}

.brand-mark {
    display: inline-flex;
    align-items: center;
    gap: 0;
    text-decoration: none;
    color: var(--text);
    font-size: 1.45rem;
    font-weight: 600;
    letter-spacing: -0.015em;
    line-height: 1;
}

.brand-mark .brand-logo {
    height: 2.7em;
    width: 2.7em;
    object-fit: contain;
    margin: -0.8em -0.7em -0.8em -0.6em;
    transform: translateY(-0.08em);
    display: block;
}

.brand-mark:hover .brand-text {
    color: var(--brand-strong);
}

.brand-text {
    transition: color 0.2s;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 1.75rem;
    align-items: center;
}

.nav-menu a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s;
    font-size: 0.92rem;
    padding: 5px 0;
}

.nav-menu a:hover {
    color: var(--brand-strong);
}

.nav-menu a.active {
    color: var(--text);
    font-weight: 600;
}

/* 英雄区 */
.hero {
    background: var(--bg);
    color: var(--text);
    padding: 108px 20px 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
}

.hero-content {
    max-width: 860px;
    position: relative;
    z-index: 1;
    animation: fadeInUp 0.6s ease-out;
}

.hero-title {
    font-size: clamp(2.4rem, 4.6vw, 3.75rem);
    margin-bottom: 1.1rem;
    font-weight: 700;
    color: var(--text);
    line-height: 1.08;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: clamp(1.05rem, 1.5vw, 1.25rem);
    margin-bottom: 0.9rem;
    color: var(--text-muted);
    font-weight: 400;
    line-height: 1.5;
}

.hero-description {
    font-size: 0.98rem;
    margin-bottom: 1.5rem;
    color: var(--text-muted);
    line-height: 1.65;
    max-width: 680px;
    margin-left: auto;
    margin-right: auto;
}

.hero-kicker {
    display: inline-flex;
    align-items: center;
    gap: 0.7rem;
    color: var(--brand-strong);
    font-size: 0.78rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.16em;
    margin-bottom: 1.6rem;
}

.hero-kicker::before,
.hero-kicker::after {
    content: '';
    width: 28px;
    height: 1px;
    background: var(--brand-strong);
    flex-shrink: 0;
}

.hero-lede {
    font-size: clamp(1.05rem, 1.5vw, 1.2rem);
    color: var(--text-muted);
    line-height: 1.65;
    margin: 0 auto 1.75rem;
    max-width: 640px;
    font-weight: 400;
}

.hero-meta {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 0.35rem 0.85rem;
    color: var(--text-subtle);
    font-size: 0.88rem;
    font-variant-numeric: tabular-nums;
    margin-top: 2rem;
}

.hero-meta > * + *::before {
    content: '·';
    margin-right: 0.85rem;
    color: var(--border-strong);
}

.hero-meta a {
    color: var(--text-subtle);
    text-decoration: none;
    transition: color 0.2s, text-decoration-color 0.2s;
    border-bottom: 1px solid transparent;
    padding-bottom: 1px;
}
.hero-meta a:hover {
    color: var(--brand-strong);
    border-bottom-color: var(--brand);
    text-decoration: none;
}

/* Collaboration line — sits below the count row, slightly quieter */
.hero-collab {
    margin: 1.1rem auto 0;
    color: var(--text-subtle);
    font-size: 0.82rem;
    line-height: 1.55;
    max-width: 520px;
    text-align: center;
}

/* 按钮 */
.hero-buttons {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
    margin-top: 1.75rem;
    flex-wrap: wrap;
}

.btn {
    padding: 11px 24px;
    font-size: 0.93rem;
    border-radius: var(--radius-pill);
    text-decoration: none;
    transition: all 0.2s;
    display: inline-block;
    font-weight: 500;
    border: 1px solid transparent;
}

.btn-primary {
    background: var(--brand);
    color: #fff;
    border-color: var(--brand);
}

.btn-primary:hover {
    background: var(--brand-strong);
    border-color: var(--brand-strong);
}

.btn-secondary {
    background: var(--bg);
    color: var(--text);
    border-color: var(--border-strong);
}

.btn-secondary:hover {
    background: var(--bg);
    border-color: var(--brand);
    color: var(--brand-strong);
}

/* Section hero — editorial left-aligned (research / news / contact / products listing) */
.section-hero {
    background: var(--bg);
    padding: 92px 20px 56px;
    border-bottom: 1px solid var(--border);
}

.section-hero .container {
    max-width: 1200px;
}

.section-hero-inner {
    max-width: 720px;
}

.section-hero-kicker {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--brand-strong);
    font-size: 0.78rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    margin-bottom: 1.25rem;
}

.section-hero-kicker::before {
    content: '';
    width: 24px;
    height: 1px;
    background: var(--brand-strong);
    flex-shrink: 0;
}

.section-hero-title {
    font-size: clamp(2rem, 4vw, 3.1rem);
    font-weight: 700;
    color: var(--text);
    line-height: 1.12;
    letter-spacing: -0.02em;
    margin: 0 0 1.1rem;
    max-width: 18ch;
}

.section-hero-lede {
    font-size: clamp(1rem, 1.3vw, 1.1rem);
    color: var(--text-muted);
    line-height: 1.6;
    max-width: 60ch;
    margin: 0;
}

.section-hero-rule {
    border: 0;
    border-top: 1px solid var(--border);
    width: 88px;
    margin: 1.75rem 0 1rem;
}

.section-hero-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem 0.85rem;
    color: var(--text-subtle);
    font-size: 0.88rem;
    font-variant-numeric: tabular-nums;
}

.section-hero-meta > * + *::before {
    content: '·';
    margin-right: 0.85rem;
    color: var(--border-strong);
}

@media (max-width: 640px) {
    .section-hero {
        padding: 88px 20px 44px;
    }
    .section-hero-title {
        max-width: none;
    }
}

/* News page — pinned story + chronological timeline */
.news-page-body {
    padding: 48px 20px 80px;
    background: var(--bg-muted);
}

.news-pinned {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-card);
    padding: 1.75rem 1.75rem 1.5rem;
    margin: 0 auto 3rem;
    max-width: 1200px;
    position: relative;
    box-shadow: var(--shadow-card);
}

.news-pinned::before {
    content: '';
    position: absolute;
    top: 1.5rem;
    bottom: 1.5rem;
    left: 0;
    width: 3px;
    background: var(--brand);
    border-radius: 0 3px 3px 0;
}

.news-pinned-label {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    color: var(--brand-strong);
    font-size: 0.74rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.16em;
    margin-bottom: 0.85rem;
}

.news-pinned-label::before {
    content: '';
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--brand);
}

.news-pinned-meta {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.5rem 0.65rem;
    margin-bottom: 0.6rem;
    font-size: 0.85rem;
    color: var(--text-subtle);
    font-variant-numeric: tabular-nums;
}

.news-pinned-title {
    font-size: clamp(1.45rem, 2.4vw, 1.95rem);
    font-weight: 700;
    color: var(--text);
    line-height: 1.2;
    letter-spacing: -0.015em;
    margin: 0 0 0.85rem;
}

.news-pinned-title a {
    color: inherit;
    text-decoration: none;
    transition: color 0.2s;
}

.news-pinned-title a:hover {
    color: var(--brand-strong);
}

.news-pinned-lede {
    color: var(--text-muted);
    font-size: 1rem;
    line-height: 1.65;
    margin: 0 0 1.1rem;
    max-width: 72ch;
}

.news-pinned-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem 1.1rem;
    align-items: baseline;
    color: var(--text-muted);
    font-size: 0.88rem;
    margin: 0 0 1.25rem;
}

.news-pinned-stats strong {
    color: var(--brand);
    font-weight: 700;
    font-size: 1.1rem;
    margin-right: 0.3rem;
    font-variant-numeric: tabular-nums;
}

.news-pinned-stats > span + span::before {
    content: '·';
    margin-right: 1.1rem;
    color: var(--border-strong);
}

.news-pinned-cta {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    color: var(--brand-strong);
    font-size: 0.95rem;
    font-weight: 600;
    text-decoration: none;
    transition: gap 0.2s;
}

.news-pinned-cta::after {
    content: '→';
    transition: transform 0.2s ease;
}

.news-pinned-cta:hover {
    color: var(--brand);
}

.news-pinned-cta:hover::after {
    transform: translateX(4px);
}

@media (max-width: 640px) {
    .news-pinned {
        padding: 1.5rem 1.25rem 1.25rem;
    }
    .news-pinned::before {
        top: 1.25rem;
        bottom: 1.25rem;
    }
}

/* News badge — shared with timeline rows */
.news-badge {
    display: inline-block;
    background: var(--brand-soft);
    color: var(--brand-strong);
    padding: 0.2rem 0.6rem;
    border-radius: var(--radius-pill);
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    line-height: 1.4;
    white-space: nowrap;
}

.news-timeline {
    max-width: 1200px;
    margin: 0 auto;
}

.news-year-header {
    display: flex;
    align-items: baseline;
    gap: 0.85rem;
    margin: 2.25rem 0 0.5rem;
    padding-bottom: 0.6rem;
    border-bottom: 1px solid var(--border-strong);
}

.news-year-header:first-child {
    margin-top: 0;
}

.news-year-label {
    font-size: clamp(1.6rem, 2.4vw, 2rem);
    font-weight: 700;
    color: var(--text);
    letter-spacing: -0.02em;
    line-height: 1;
    font-variant-numeric: tabular-nums;
}

.news-year-count {
    font-size: 0.85rem;
    color: var(--text-subtle);
    font-weight: 500;
    letter-spacing: 0.02em;
}

.news-timeline-row {
    display: grid;
    grid-template-columns: 110px minmax(96px, auto) 1fr;
    align-items: baseline;
    gap: 1.5rem;
    padding: 1.1rem 0.5rem 1.1rem 0.5rem;
    border-bottom: 1px solid var(--border);
    text-decoration: none;
    color: inherit;
    transition: background-color 0.18s ease, padding 0.18s ease;
    border-radius: 8px;
}

.news-timeline-row:hover {
    background: rgba(33, 150, 243, 0.045);
    padding-left: 0.85rem;
}

.news-timeline-row.is-static {
    cursor: default;
}

.news-timeline-row.is-static:hover {
    background: transparent;
    padding-left: 0.5rem;
}

.news-timeline-date {
    color: var(--text-subtle);
    font-size: 0.86rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    font-variant-numeric: tabular-nums;
    line-height: 1.5;
}

.news-timeline-badge {
    align-self: baseline;
    line-height: 1.2;
}

.news-timeline-content {
    min-width: 0;
}

.news-timeline-title {
    font-size: 1.02rem;
    color: var(--text);
    font-weight: 600;
    letter-spacing: -0.01em;
    line-height: 1.4;
    margin: 0 0 0.25rem;
    display: inline-flex;
    align-items: baseline;
    gap: 0.4rem;
    transition: color 0.18s ease;
}

.news-timeline-row:hover .news-timeline-title {
    color: var(--brand-strong);
}

.news-timeline-title::after {
    content: '→';
    color: var(--text-subtle);
    font-weight: 500;
    transform: translateX(0);
    transition: transform 0.2s ease, color 0.2s ease;
}

.news-timeline-row:hover .news-timeline-title::after {
    color: var(--brand-strong);
    transform: translateX(4px);
}

.news-timeline-row.is-static .news-timeline-title::after {
    display: none;
}

.news-timeline-excerpt {
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.55;
    margin: 0;
}

.news-timeline-meta-mobile {
    display: none;
}

@media (max-width: 720px) {
    .news-timeline-row {
        grid-template-columns: 1fr;
        gap: 0.45rem;
        padding: 1rem 0.5rem;
    }
    .news-timeline-row:hover {
        padding-left: 0.5rem;
    }
    .news-timeline-date,
    .news-timeline-badge {
        display: none;
    }
    .news-timeline-meta-mobile {
        display: flex;
        align-items: center;
        gap: 0.65rem;
        flex-wrap: wrap;
        margin-bottom: 0.15rem;
        font-size: 0.82rem;
        color: var(--text-subtle);
        font-variant-numeric: tabular-nums;
    }
}

/* 关于我们 */
.about {
    padding: 64px 20px;
    background: var(--bg);
    position: relative;
    border-top: 1px solid var(--border);
}

.about h2 {
    font-size: clamp(1.75rem, 2.8vw, 2.25rem);
    margin-bottom: 1.25rem;
    text-align: center;
    color: var(--text);
    font-weight: 600;
    letter-spacing: -0.015em;
}

.about p {
    font-size: 1rem;
    text-align: center;
    max-width: 760px;
    margin: 0 auto;
    color: var(--text-muted);
    line-height: 1.7;
}

/* 研究板块 */
.research {
    padding: 64px 20px;
    background: var(--bg);
    position: relative;
}

.section-title {
    font-size: clamp(1.75rem, 2.8vw, 2.25rem);
    margin-bottom: 1.75rem;
    text-align: center;
    color: var(--text);
    font-weight: 600;
    letter-spacing: -0.015em;
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.1rem;
    margin-top: 1.75rem;
}

/* Section header — section title with an inline "View all →" link */
.section-header {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 1.5rem;
    flex-wrap: wrap;
    margin-bottom: 0.25rem;
}
.section-header .section-title { margin-bottom: 0; }
.section-more {
    color: var(--text-subtle);
    text-decoration: none;
    font-size: 0.92rem;
    font-weight: 500;
    transition: color 0.2s, transform 0.2s;
    white-space: nowrap;
}
.section-more:hover {
    color: var(--brand-strong);
    text-decoration: none;
    transform: translateX(2px);
}

.research-card {
    background: var(--bg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-card);
    border-radius: var(--radius-card);
    padding: 1.5rem;
    position: relative;
    overflow: hidden;
    transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    min-height: 240px;
    text-decoration: none;
    color: inherit;
}

.research-card:hover {
    transform: translateY(-3px);
    border-color: var(--brand-ring);
    box-shadow: var(--shadow-card-hover);
}

.card-content {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    flex: 1;
}

/* Image-first card layout — used when a card has a hero image */
.card-image {
    margin: -1.5rem -1.5rem 1.1rem;
    border-radius: var(--radius-card) var(--radius-card) 0 0;
    overflow: hidden;
    aspect-ratio: 16 / 10;
    background: var(--bg-muted);
}

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

.card-icon {
    font-size: 2rem;
    margin-bottom: 0.75rem;
    color: var(--brand);
}

.research-card h3 {
    color: var(--text);
    font-size: 1.18rem;
    margin-bottom: 0.4rem;
    font-weight: 600;
    letter-spacing: -0.01em;
    line-height: 1.3;
}

.card-meta {
    color: var(--text-subtle);
    font-size: 0.82rem;
    margin-bottom: 0.75rem;
    font-weight: 500;
}

.research-card p {
    color: var(--text-muted);
    line-height: 1.55;
    margin-bottom: 1.1rem;
    font-size: 0.92rem;
}

.card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-top: auto;
}

.tag {
    background: var(--brand-soft);
    color: var(--brand-strong);
    padding: 0.22rem 0.6rem;
    border-radius: var(--radius-pill);
    font-size: 0.76rem;
    border: 1px solid transparent;
    font-weight: 500;
}

/* 产品板块 */
.products {
    padding: 64px 20px;
    background: var(--bg-muted);
    position: relative;
}

.products-showcase {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.1rem;
    margin-top: 1.75rem;
}

.product-item {
    background: var(--bg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-card);
    border-radius: var(--radius-card);
    overflow: hidden;
    transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.product-item:hover {
    border-color: var(--brand-ring);
    transform: translateY(-3px);
    box-shadow: var(--shadow-card-hover);
}

/* Featured product */
.product-item.featured {
    display: grid;
    grid-template-columns: 0.8fr 1.6fr;
    gap: 1.75rem;
    padding: 1.5rem;
    background: var(--bg);
    align-items: center;
}

@media (max-width: 768px) {
    .product-item.featured {
        grid-template-columns: 1fr;
    }
}

.product-visual {
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background: var(--bg-muted);
    border-radius: var(--radius-card);
    overflow: hidden;
    aspect-ratio: 1 / 1;
    padding: 1.5rem;
}

.product-visual img {
    max-width: 70%;
    max-height: 70%;
    object-fit: contain;
    display: block;
}

.product-visual i {
    font-size: clamp(3rem, 7vw, 4.5rem);
    color: var(--brand);
    line-height: 1;
}

.product-icon-wrapper {
    position: relative;
    width: 160px;
    height: 160px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-icon {
    font-size: 3rem;
    z-index: 2;
    color: var(--brand);
}

.product-info h3 {
    font-size: clamp(1.35rem, 2vw, 1.65rem);
    color: var(--text);
    margin-bottom: 0.6rem;
    font-weight: 600;
    letter-spacing: -0.015em;
}

.product-badge {
    display: inline-block;
    background: var(--brand-soft);
    color: var(--brand-strong);
    padding: 0.25rem 0.7rem;
    border-radius: var(--radius-pill);
    font-size: 0.75rem;
    border: 1px solid transparent;
    margin-bottom: 0.85rem;
    font-weight: 500;
    letter-spacing: 0.01em;
}

.product-description {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
    margin-bottom: 1.1rem;
}

.product-features {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.5rem 1rem;
    margin-bottom: 1.1rem;
}

.feature {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-muted);
    font-size: 0.88rem;
}

.feature-icon {
    color: var(--brand);
    font-size: 0.9rem;
    width: 16px;
    display: inline-block;
    text-align: center;
}

.product-btn {
    display: inline-block;
    background: var(--brand);
    color: #fff;
    border: 1px solid var(--brand);
    padding: 10px 22px;
    border-radius: var(--radius-pill);
    font-size: 0.92rem;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
    text-align: center;
    font-weight: 500;
}

.product-btn:hover {
    background: var(--brand-strong);
    border-color: var(--brand-strong);
}

.product-btn-small {
    display: inline-block;
    background: var(--brand);
    color: #fff;
    border: 1px solid var(--brand);
    padding: 7px 18px;
    border-radius: var(--radius-pill);
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.2s;
    margin-top: 8px;
    text-decoration: none;
    font-weight: 500;
}

.product-btn-small:hover {
    background: var(--brand-strong);
    border-color: var(--brand-strong);
}

/* Compact product items */
.product-compact {
    padding: 1.5rem;
}

.product-header {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    margin-bottom: 0.85rem;
}

.product-icon-small {
    font-size: 1.1rem;
    color: var(--brand);
    width: 36px;
    height: 36px;
    background: var(--brand-soft);
    border: 1px solid transparent;
    border-radius: 9px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.product-buttons {
    display: flex;
    gap: 0.75rem;
    margin-top: 1.25rem;
    flex-wrap: wrap;
}

.product-btn-secondary {
    display: inline-block;
    background: var(--bg);
    color: var(--text);
    border: 1px solid var(--border-strong);
    padding: 10px 22px;
    border-radius: var(--radius-pill);
    font-size: 0.92rem;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
    text-align: center;
    font-weight: 500;
}

.product-btn-secondary:hover {
    background: var(--bg);
    border-color: var(--brand);
    color: var(--brand-strong);
}

.product-features-compact {
    margin: 1rem 0 1.25rem;
}

.feature-compact {
    display: flex;
    align-items: center;
    margin-bottom: 0.5rem;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.feature-icon-small {
    color: var(--brand);
    margin-right: 9px;
    font-size: 0.85rem;
    width: 14px;
    display: inline-block;
    text-align: center;
}

.product-compact h3 {
    color: var(--text);
    font-size: 1.18rem;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.product-compact p {
    color: var(--text-muted);
    line-height: 1.55;
    margin-bottom: 1rem;
    font-size: 0.92rem;
}

.product-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    text-align: center;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

.stat {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.stat-value {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--brand);
    letter-spacing: -0.01em;
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-subtle);
}

/* 服务板块 */
.services {
    padding: 64px 20px;
    background: var(--bg);
    position: relative;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.1rem;
    margin-top: 1.75rem;
}

.service-card {
    background: var(--bg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-card);
    border-radius: var(--radius-card);
    padding: 1.5rem;
    position: relative;
    overflow: hidden;
    transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.service-card:hover {
    transform: translateY(-3px);
    border-color: var(--brand-ring);
    box-shadow: var(--shadow-card-hover);
}

.service-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
    display: inline-block;
    color: var(--brand);
}

.service-card h3 {
    color: var(--text);
    font-size: 1.18rem;
    margin-bottom: 1rem;
    font-weight: 600;
    letter-spacing: -0.01em;
}

.service-features {
    margin-bottom: 1.1rem;
}

.service-feature {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.check-icon {
    color: var(--brand);
    font-weight: bold;
    font-size: 1rem;
}

.service-metrics {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-top: 1.25rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

.metric {
    text-align: center;
}

.metric-value {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--brand);
    letter-spacing: -0.01em;
}

.metric-label {
    font-size: 0.8rem;
    color: var(--text-subtle);
    margin-top: 0.2rem;
}

.service-highlight {
    background: var(--brand-soft);
    color: var(--brand-strong);
    padding: 0.75rem 1rem;
    border-radius: 10px;
    text-align: center;
    margin-top: 1.1rem;
    border: 1px solid transparent;
    font-weight: 500;
    font-size: 0.9rem;
}

.service-btn {
    background: var(--brand);
    color: #fff;
    border: 1px solid var(--brand);
    padding: 10px 22px;
    border-radius: var(--radius-pill);
    font-size: 0.92rem;
    cursor: pointer;
    transition: all 0.2s;
    margin-top: 1.1rem;
    width: 100%;
    font-weight: 500;
}

.service-btn:hover {
    background: var(--brand-strong);
    border-color: var(--brand-strong);
}

/* 页脚 */
.footer {
    background: var(--bg);
    color: var(--text-muted);
    padding: 48px 20px 24px;
    border-top: 1px solid var(--border);
    margin-top: 48px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 2.5rem;
    margin-bottom: 1.75rem;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.footer-logo-wrapper {
    max-width: 180px;
    height: 48px;
    display: flex;
    align-items: center;
}

.footer-logo {
    width: 100%;
    height: auto;
    max-height: 100%;
    object-fit: contain;
}

.footer-desc {
    font-size: 0.98rem;
    color: var(--text);
    font-weight: 600;
}

.footer-tagline {
    color: var(--text-muted);
    font-size: 0.88rem;
    line-height: 1.55;
}

.footer-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.footer-column h4 {
    color: var(--text);
    margin-bottom: 0.7rem;
    font-size: 0.88rem;
    font-weight: 600;
    letter-spacing: 0.01em;
}

.footer-column ul {
    list-style: none;
}

.footer-column li {
    margin-bottom: 0.45rem;
}

.footer-column a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s;
    font-size: 0.88rem;
}

.footer-column a:hover {
    color: var(--brand-strong);
}

.footer-bottom {
    text-align: center;
    padding-top: 1.25rem;
    border-top: 1px solid var(--border);
    color: var(--text-subtle);
    font-size: 0.82rem;
    max-width: 1200px;
    margin: 0 auto;
}

/* In-content links */
.content-link,
main a:not(.btn):not(.product-btn):not(.product-btn-small):not(.product-btn-secondary):not(.service-btn):not(.research-card):not(.product-item) {
    color: var(--brand-strong);
    text-decoration: none;
    transition: color 0.2s;
}

.content-link:hover,
main a:not(.btn):not(.product-btn):not(.product-btn-small):not(.product-btn-secondary):not(.service-btn):not(.research-card):not(.product-item):hover {
    color: var(--brand);
    text-decoration: underline;
    text-underline-offset: 2px;
}

/* ============================================================
   Article — blog-style research post
   Used by /research/*.html paper detail pages.
   ============================================================ */

.article-page {
    background: var(--bg);
    color: var(--text);
    padding: 96px 20px 80px;
    font-family: var(--font-display);
}

.article-back {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    color: var(--text-subtle);
    text-decoration: none;
    font-size: 0.875rem;
    margin-bottom: 2.5rem;
    width: max-content;
    transition: color 0.2s, transform 0.2s;
}
.article-back:hover { color: var(--text); transform: translateX(-2px); text-decoration: none; }

.article-hero {
    max-width: 760px;
    margin: 0 auto 3rem;
    text-align: left;
}

.article-eyebrow {
    display: inline-block;
    color: var(--brand-strong);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 1rem;
}

.article-title {
    font-size: clamp(2rem, 4vw, 2.75rem);
    font-weight: 600;
    line-height: 1.15;
    letter-spacing: -0.02em;
    color: var(--text);
    margin: 0 0 0.75rem;
}

.article-subtitle {
    font-size: 1.18rem;
    line-height: 1.5;
    color: var(--text-muted);
    margin: 0 0 1.75rem;
    font-weight: 400;
}

.article-meta {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    font-size: 0.88rem;
    color: var(--text-subtle);
    margin-bottom: 1.5rem;
    line-height: 1.55;
}

.article-meta-authors {
    color: var(--text-muted);
    font-size: 0.92rem;
}

.article-meta-affil {
    color: var(--text-subtle);
    font-size: 0.85rem;
}
.article-meta-affil strong {
    color: var(--brand-strong);
    font-weight: 600;
}

.article-meta-stamp {
    color: var(--text-subtle);
    font-size: 0.82rem;
    font-variant-numeric: tabular-nums;
}
.article-meta-stamp > span + span::before {
    content: "·";
    margin: 0 0.5rem;
    color: var(--border-strong);
}

.article-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.article-actions .article-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.45rem 0.95rem;
    background: var(--bg);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius-pill);
    color: var(--text);
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: 500;
    transition: border-color 0.2s, color 0.2s, background 0.2s;
}
.article-actions .article-link:hover {
    border-color: var(--brand);
    color: var(--brand-strong);
    background: var(--brand-soft);
    text-decoration: none;
}
.article-actions .article-link.is-disabled {
    opacity: 0.55;
    cursor: not-allowed;
}
.article-actions .article-link.is-disabled:hover {
    border-color: var(--border-strong);
    color: var(--text);
    background: var(--bg);
}

.article-figures {
    max-width: 760px;
    margin: 0 auto 3rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 1.5rem 2rem;
    padding: 1.5rem 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.article-figure-stat {
    text-align: left;
}
.article-figure-stat .num {
    display: block;
    font-size: 1.6rem;
    font-weight: 600;
    color: var(--text);
    letter-spacing: -0.01em;
    font-variant-numeric: tabular-nums;
    line-height: 1.1;
    margin-bottom: 0.25rem;
}
.article-figure-stat .label {
    font-size: 0.78rem;
    color: var(--text-subtle);
    line-height: 1.35;
}

.article {
    max-width: 720px;
    margin: 0 auto;
    font-size: 1.0625rem;
    line-height: 1.75;
    color: var(--text);
}

.article p {
    margin: 0 0 1.25rem;
    color: var(--text);
}

.article a {
    color: var(--brand-strong);
    text-decoration: underline;
    text-underline-offset: 3px;
    text-decoration-thickness: 1px;
}
.article a:hover { color: var(--brand); }

.article-lede {
    font-size: 1.18rem;
    line-height: 1.6;
    color: var(--text);
    margin: 0 0 2.5rem;
}

.article-section { margin: 3rem 0; }
.article-section > :first-child { margin-top: 0; }
.article-section > :last-child { margin-bottom: 0; }

.article-section h2 {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.015em;
    color: var(--text);
    margin: 2.5rem 0 1rem;
    line-height: 1.25;
}

.article-section h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text);
    margin: 1.75rem 0 0.5rem;
    line-height: 1.35;
}

.article ul, .article ol {
    margin: 0 0 1.5rem;
    padding-left: 1.25rem;
}
.article li { margin-bottom: 0.5rem; line-height: 1.7; }

.article-pullquote {
    border-left: 2px solid var(--brand);
    padding: 0.25rem 0 0.25rem 1.25rem;
    margin: 2rem 0;
    font-size: 1.125rem;
    line-height: 1.55;
    font-style: italic;
    color: var(--text);
}

.article-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0 0.75rem;
    font-size: 0.95rem;
    font-variant-numeric: tabular-nums;
}
.article-table thead th {
    text-align: left;
    font-weight: 600;
    font-size: 0.75rem;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--text-subtle);
    padding: 0.5rem 0.75rem;
    border-bottom: 1px solid var(--border-strong);
}
.article-table tbody td {
    padding: 0.7rem 0.75rem;
    border-bottom: 1px solid var(--border);
    color: var(--text);
    vertical-align: top;
}
.article-table tbody td:first-child { padding-left: 0; }
.article-table tbody td:last-child  { padding-right: 0; }
.article-table thead th:first-child { padding-left: 0; }
.article-table thead th:last-child  { padding-right: 0; }
.article-table tbody tr:last-child td { border-bottom: none; }
.article-table tbody tr.is-ours td { font-weight: 600; }
.article-table tbody tr.is-ours td:first-child {
    box-shadow: inset 2px 0 0 var(--brand);
    padding-left: 0.6rem;
}
.article-table-num { text-align: right; font-variant-numeric: tabular-nums; }

.article-figure-caption {
    font-size: 0.8125rem;
    color: var(--text-subtle);
    font-style: italic;
    line-height: 1.5;
    margin: 0 0 2rem;
}

.article-divider {
    border: none;
    height: 1px;
    background: var(--border);
    margin: 3rem auto;
    max-width: 720px;
}

.article-impact {
    margin: 1.5rem 0;
}
.article-impact > div {
    margin-bottom: 1.25rem;
}
.article-impact > div > strong {
    display: block;
    color: var(--text);
    font-weight: 600;
    margin-bottom: 0.15rem;
}
.article-impact > div > span {
    color: var(--text);
    line-height: 1.7;
}

.article-footer {
    max-width: 720px;
    margin: 4rem auto 0;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    color: var(--text-subtle);
    font-size: 0.875rem;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
}
.article-footer a {
    color: var(--text-subtle);
    text-decoration: none;
}
.article-footer a:hover { color: var(--brand-strong); }

@media (max-width: 720px) {
    .article-page { padding: 80px 20px 64px; }
    .article-hero, .article-figures, .article, .article-footer, .article-divider { max-width: 100%; }
    .article-title { font-size: 1.85rem; }
    .article-subtitle { font-size: 1.05rem; }
    .article-figures { grid-template-columns: repeat(2, 1fr); }
    .article-table { font-size: 0.88rem; }
}

/* ============================================================
   Product page — image-rich blog layout
   Used by /products/*.html detail pages. Shares the article tokens
   (sans-serif, narrow column for prose, hairline borders) but swaps
   the article hero for a 2-up text + image hero, adds alternating
   image+text feature rows, and a quiet CTA card at the bottom.
   ============================================================ */
.product-page {
    background: var(--bg);
    color: var(--text);
    padding: 96px 20px 80px;
    font-family: var(--font-display);
}

.product-back-row {
    max-width: 1080px;
    margin: 0 auto 2.5rem;
}
.product-back {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    color: var(--text-subtle);
    text-decoration: none;
    font-size: 0.875rem;
    transition: color 0.2s, transform 0.2s;
}
.product-back:hover { color: var(--text); transform: translateX(-2px); text-decoration: none; }

.product-hero {
    max-width: 1080px;
    margin: 0 auto 4rem;
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 4rem;
    align-items: center;
}
.product-hero-text { max-width: 540px; }
.product-hero-image {
    width: 100%;
    border-radius: 20px;
    border: 1px solid var(--border);
    background: var(--bg-muted);
    overflow: hidden;
}
.product-hero-image img { display: block; width: 100%; height: auto; }

.product-logo-mark {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    margin-bottom: 1.25rem;
    border-radius: 14px;
    background: var(--brand-soft);
    padding: 6px;
}
.product-logo-mark img { width: 100%; height: 100%; object-fit: contain; display: block; }

.product-eyebrow {
    display: inline-block;
    color: var(--brand-strong);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 0.75rem;
}

.product-title {
    font-size: clamp(2.2rem, 4.2vw, 3.2rem);
    font-weight: 600;
    line-height: 1.1;
    letter-spacing: -0.025em;
    margin: 0 0 1rem;
    color: var(--text);
}

.product-subtitle {
    font-size: clamp(1.1rem, 1.4vw, 1.25rem);
    line-height: 1.45;
    color: var(--text-muted);
    margin: 0 0 2rem;
    font-weight: 400;
}

.product-actions {
    display: flex;
    gap: 0.6rem;
    flex-wrap: wrap;
    align-items: center;
}
.product-actions .btn { padding: 10px 22px; font-size: 0.92rem; }

.product-stats {
    max-width: 960px;
    margin: 0 auto 4rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 1.5rem 2.5rem;
    padding: 2rem 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}
.product-stat .num {
    display: block;
    font-size: 2rem;
    font-weight: 600;
    line-height: 1.05;
    letter-spacing: -0.02em;
    color: var(--text);
    margin-bottom: 0.35rem;
    font-variant-numeric: tabular-nums;
}
.product-stat .label {
    color: var(--text-subtle);
    font-size: 0.85rem;
    line-height: 1.45;
}

.product-body {
    max-width: 760px;
    margin: 0 auto;
    font-size: 1.0625rem;
    line-height: 1.75;
    color: var(--text);
}
.product-body > p { margin: 0 0 1.25rem; }

.product-lede {
    font-size: 1.18rem;
    line-height: 1.6;
    color: var(--text);
    margin: 0 auto 3rem;
    max-width: 760px;
}

.product-section { margin: 4rem 0; }
.product-section > h2 {
    max-width: 760px;
    margin: 0 auto 1.5rem;
    font-size: 1.75rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--text);
    line-height: 1.2;
}
.product-section > p,
.product-section > ul,
.product-section > ol {
    max-width: 760px;
    margin-left: auto;
    margin-right: auto;
}
.product-section > p { margin-bottom: 1.25rem; line-height: 1.7; }
.product-section ul, .product-section ol { padding-left: 1.25rem; }
.product-section li { margin-bottom: 0.5rem; line-height: 1.7; }

.product-showcase {
    max-width: 1080px;
    margin: 3rem auto;
}
.product-showcase img {
    display: block;
    width: 100%;
    height: auto;
    border-radius: 16px;
    border: 1px solid var(--border);
    background: var(--bg-muted);
}
.product-showcase figcaption {
    margin-top: 0.75rem;
    color: var(--text-subtle);
    font-size: 0.875rem;
    font-style: italic;
    text-align: center;
    max-width: 720px;
    margin-left: auto;
    margin-right: auto;
}

/* Alternating feature row: image + text */
.product-feature {
    max-width: 1080px;
    margin: 4rem auto;
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: 3rem;
    align-items: center;
}
.product-feature.is-flipped { grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr); }
.product-feature.is-flipped .product-feature-image { order: 2; }
.product-feature-image img {
    display: block;
    width: 100%;
    height: auto;
    border-radius: 14px;
    border: 1px solid var(--border);
    background: var(--bg-muted);
}
.product-feature-text h3 {
    font-size: 1.45rem;
    font-weight: 600;
    margin: 0 0 1rem;
    letter-spacing: -0.018em;
    color: var(--text);
    line-height: 1.25;
}
.product-feature-text p { color: var(--text-muted); margin: 0 0 1rem; line-height: 1.65; }
.product-feature-text p:last-child { margin-bottom: 0; }

/* Capability grid — short bulleted feature list */
.product-capabilities {
    max-width: 960px;
    margin: 2rem auto 0;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 2.25rem 3rem;
}
.product-capability h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin: 0 0 0.5rem;
    color: var(--text);
}
.product-capability p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
    margin: 0;
}

/* CTA card at the bottom of a product page */
.product-cta {
    max-width: 760px;
    margin: 5rem auto 0;
    padding: 3rem;
    text-align: center;
    border: 1px solid var(--border);
    border-radius: 20px;
    background: var(--bg-muted);
}
.product-cta h2 {
    font-size: 1.75rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin: 0 0 0.75rem;
    color: var(--text);
}
.product-cta p {
    color: var(--text-muted);
    margin: 0 0 1.75rem;
    line-height: 1.6;
}

@media (max-width: 900px) {
    .product-hero, .product-feature, .product-feature.is-flipped {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    .product-feature.is-flipped .product-feature-image { order: 0; }
    .product-cta { padding: 2rem 1.5rem; }
}

/* Soften screenshots in dark mode so they don't punch through */
[data-theme="dark"] .product-feature-image img,
[data-theme="dark"] .product-showcase img,
[data-theme="dark"] .product-hero-image img {
    filter: brightness(0.92) contrast(1.04);
}

/* ============================================================
   Theme toggle (sun / moon) — sits as last item in nav-menu.
   Click handler in navbar-loader.js; FOUC-prevention in inline <head> script.
   ============================================================ */
.nav-menu .theme-toggle-item { display: flex; align-items: center; }

.theme-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    padding: 0;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: var(--radius-pill);
    color: var(--text-muted);
    cursor: pointer;
    transition: color 0.2s, border-color 0.2s, background 0.2s;
}
.theme-toggle:hover {
    color: var(--brand-strong);
    border-color: var(--brand);
    background: var(--brand-soft);
}
.theme-toggle svg { width: 16px; height: 16px; display: block; }

/* Show sun in dark mode (so click → light), moon in light mode (so click → dark) */
.theme-toggle .theme-icon-sun { display: none; }
.theme-toggle .theme-icon-moon { display: block; }
[data-theme="dark"] .theme-toggle .theme-icon-sun { display: block; }
[data-theme="dark"] .theme-toggle .theme-icon-moon { display: none; }

/* Smooth color transitions site-wide when theme flips */
html { transition: background-color 0.2s ease; }
body { transition: background-color 0.2s ease, color 0.2s ease; }

/* Dark-mode tweaks for elements that rely on subtle off-white tints */
[data-theme="dark"] .article-pullquote { color: var(--text); }
[data-theme="dark"] .btn-primary { color: #0d0d0f; }
[data-theme="dark"] .article-link.is-disabled { opacity: 0.45; }
[data-theme="dark"] img { /* slightly dim screenshots/photos so they don't punch through dark UI */
    /* opt-in only: pages that want this can add class="img-dim-on-dark" */
}
[data-theme="dark"] .img-dim-on-dark { filter: brightness(0.88) contrast(1.05); }