/* ===================== Base ===================== */
:root {
    --max: 1460px;
    --black: #111;
    --text: #1a1a1a;
    --text-2: #666;
    --text-3: #999;
    --line: #e5e5e5;
    --bg: #ffffff;
}

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

html, body {
    background: var(--bg);
    color: var(--text);
    font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
        "Helvetica Neue", Arial, "Source Han Sans CN", sans-serif;
    font-size: 16px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img { display: block; max-width: 100%; height: auto; }

.container {
    max-width: var(--max);
    margin: 0 auto;
    padding: 0;
}

/* ===================== Header ===================== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    background: #fff;
}
.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 110px;
    padding: 0 0;
}
.brand {
    display: inline-flex;
    align-items: center;
    gap: 14px;
}
.brand-mark {
    width: 48px;
    height: 48px;
    flex: none;
}
.brand-text {
    font-weight: 800;
    font-size: 36px;
    letter-spacing: 2px;
    color: var(--black);
    font-family: "Helvetica Neue", Arial, "PingFang SC", sans-serif;
    line-height: 1;
}
.top-nav {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 15px;
    color: #333;
}
.lang-btn {
    background: none;
    border: 0;
    cursor: pointer;
    padding: 4px 2px;
    font-family: inherit;
    font-size: 14px;
    color: #777;
    letter-spacing: 0.4px;
    line-height: 1;
    transition: color .2s, border-color .2s, font-weight .2s;
    border-bottom: 2px solid transparent;
}
.lang-btn:hover {
    color: #111;
}
.lang-btn.is-active {
    color: #111;
    font-weight: 700;
    border-bottom-color: #111;
}
.lang-sep {
    color: #d0d0d0;
    font-size: 13px;
    user-select: none;
}
.search-btn {
    background: none;
    border: 0;
    cursor: pointer;
    padding: 4px;
    margin-left: 10px;
    display: inline-flex;
    align-items: center;
}
.search-btn svg { width: 22px; height: 22px; }

/* ===================== Hero ===================== */
.hero {
    position: relative;
    width: 100%;
    max-width: 1920px;
    margin: 0 auto;
    aspect-ratio: 1920 / 950;
    background: #000;
    overflow: hidden;
}
.hero-bg {
    position: absolute;
    inset: 0;
    background-image: url('assets/hero_bg.jpg');
    background-size: cover;
    background-position: center top;
    background-repeat: no-repeat;
}
.hero-overlay {
    position: absolute;
    inset: 0;
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-end;
    padding-bottom: 4.5%;
    text-align: center;
}
.hero-title {
    color: #e7b820;
    font-size: 72px;
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: 6px;
    margin: 0 0 4.5%;
    padding: 0 5%;
    text-shadow: 0 3px 18px rgba(0, 0, 0, 0.45);
    font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
        "Helvetica Neue", Arial, sans-serif;
}
html[data-lang="en"] .hero-title {
    font-size: 64px;
    letter-spacing: 2px;
    font-family: "Helvetica Neue", "Arial Black", "Segoe UI", Arial, sans-serif;
}
.hero-dots {
    display: inline-flex;
    gap: 14px;
    align-items: center;
    justify-content: center;
}
.hero-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.45);
    transition: all .25s ease;
}
.hero-dot--active {
    width: 28px;
    border-radius: 6px;
    background: rgba(255, 255, 255, 0.92);
}

/* ===================== Section Basics ===================== */
.section {
    padding: 100px 0 0;
}

.section-title {
    font-size: 48px;
    line-height: 1.2;
    font-weight: 700;
    color: var(--black);
    letter-spacing: 1px;
}
.section-head {
    display: flex;
    align-items: flex-end;
    gap: 24px;
    margin-bottom: 46px;
    position: relative;
}
.view-more {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: #aaa;
    font-size: 13px;
    padding-bottom: 8px;
}
.view-more .vm-arrow {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    border: 1px solid #ccc;
    border-radius: 50%;
    color: #bbb;
}
.view-more .vm-arrow svg { width: 10px; height: 10px; }

/* ===================== About ===================== */
.about {
    padding: 120px 0 50px;
}
.about .section-title {
    font-size: 60px;
    letter-spacing: 2px;
    font-weight: 800;
    line-height: 1.15;
}
.about .title-underline {
    display: block;
    width: 40px;
    height: 2px;
    background: #bbb;
    margin: 40px 0 44px;
}
.about-text {
    max-width: 100%;
    color: #333;
    font-size: 26px;
    line-height: 2.0;
    text-align: justify;
    letter-spacing: 1px;
}

/* ===================== Services ===================== */
.services {
    padding-top: 100px;
}
.services-banner {
    margin: 24px 0 90px;
    overflow: hidden;
}
.services-banner img {
    width: 100%;
    height: auto;
    display: block;
}
.services-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0;
    position: relative;
}

.service-item {
    text-align: center;
    padding: 30px 20px;
    position: relative;
}
.service-item + .service-item::before {
    content: "";
    position: absolute;
    top: 40px;
    bottom: 40px;
    left: 0;
    width: 1px;
    background: #e5e5e5;
}

.service-icon {
    width: 110px;
    height: 110px;
    margin: 0 auto 30px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.service-icon svg {
    width: 100%;
    height: 100%;
}
.service-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--black);
    margin-bottom: 32px;
    letter-spacing: 0.5px;
}
.service-list {
    color: #999;
    font-size: 20px;
    line-height: 2.1;
}

/* ===================== Clients ===================== */
.clients {
    padding-top: 110px;
}
.clients-subtitle {
    font-size: 22px;
    color: var(--black);
    font-weight: 700;
    margin-top: -20px;
    margin-bottom: 34px;
    letter-spacing: 0.5px;
}
.clients-grid-wrap {
    width: 100%;
}
.clients-grid-img {
    width: 100%;
    height: auto;
    display: block;
}

/* ===================== Cases ===================== */
.cases {
    padding-top: 110px;
}
.cases .section-head {
    align-items: center;
}
.case-pager {
    margin-left: auto;
    display: inline-flex;
    gap: 14px;
}
.pager-btn {
    width: 62px;
    height: 36px;
    border: 1px solid #ddd;
    border-radius: 30px;
    background: #fff;
    color: #bbb;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: all .2s;
}
.pager-btn svg { width: 16px; height: 16px; }
.pager-btn:hover { color: #666; border-color: #aaa; }
.pager-btn--active { color: #333; border-color: #999; }

.cases-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}
.case-card {
    background: #fff;
    display: flex;
    flex-direction: column;
}
.case-media {
    width: 100%;
    overflow: hidden;
    aspect-ratio: 485 / 275;
    background: #eee;
}
.case-media img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}
.case-body {
    padding: 34px 10px 0;
}
.case-label {
    display: block;
    font-size: 15px;
    color: #999;
    margin-bottom: 18px;
    letter-spacing: 0.5px;
}
.case-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--black);
    margin-bottom: 30px;
    letter-spacing: 0.2px;
    line-height: 1.35;
}
.case-list {
    color: #888;
    font-size: 17px;
    line-height: 2;
    margin-bottom: 32px;
}
.case-divider {
    width: 36px;
    height: 2px;
    background: #ccc;
    margin-bottom: 18px;
}
.case-foot {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: #aaa;
    font-size: 14px;
}
.case-views {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}
.case-views svg { width: 16px; height: 16px; }

/* ===================== News ===================== */
.news {
    padding-top: 110px;
    padding-bottom: 120px;
}
.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    column-gap: 70px;
    row-gap: 0;
    border-top: 1px solid var(--line);
}
.news-item {
    padding: 28px 0 24px;
    border-bottom: 1px solid var(--line);
    display: flex;
    flex-direction: column;
    gap: 14px;
}
.news-label {
    font-size: 14px;
    color: #aaa;
    letter-spacing: 0.5px;
}
.news-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--black);
    line-height: 1.55;
    min-height: 2.6em;
    letter-spacing: 0.2px;
}
.news-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: #bbb;
    font-size: 13px;
    margin-top: 20px;
}
.news-views {
    display: inline-flex;
    align-items: center;
    gap: 5px;
}
.news-views svg { width: 16px; height: 16px; }

/* ===================== Footer ===================== */
.site-footer {
    background: #0b0b0b;
    color: #bbb;
    padding: 48px 0;
    font-size: 14px;
}
.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 40px;
    flex-wrap: wrap;
}
.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    color: #fff;
    font-weight: 800;
    font-size: 30px;
    letter-spacing: 2px;
    font-family: "Helvetica Neue", Arial, "PingFang SC", sans-serif;
    line-height: 1;
}
.footer-mark {
    width: 42px;
    height: 42px;
}
.footer-col {
    color: #c2c2c2;
    line-height: 2;
    font-size: 14px;
}
.footer-col p { margin: 0; }

.footer-socials {
    display: inline-flex;
    gap: 14px;
}
.social {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: #1e1e1e;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: background .2s;
}
.social svg { width: 20px; height: 20px; }
.social:hover { background: #333; }

/* ===================== English-mode typography tweaks =====================
 * English copy tends to be longer than Chinese, so we relax tracking,
 * shrink a couple of tight headlines, and switch to a Latin font stack.
 * =========================================================================*/
html[data-lang="en"] body {
    font-family: "Helvetica Neue", "Segoe UI", "Inter", Arial, sans-serif;
}
html[data-lang="en"] .brand-text,
html[data-lang="en"] .footer-brand {
    letter-spacing: 3px;
}
html[data-lang="en"] .about .section-title {
    font-size: 52px;
    letter-spacing: 0.5px;
}
html[data-lang="en"] .about-text {
    font-size: 22px;
    line-height: 1.8;
    letter-spacing: 0;
    text-align: left;
}
html[data-lang="en"] .section-title {
    letter-spacing: 0.5px;
}
html[data-lang="en"] .service-title {
    font-size: 24px;
    letter-spacing: 0;
}
html[data-lang="en"] .service-list {
    font-size: 18px;
    letter-spacing: 0;
}
html[data-lang="en"] .clients-subtitle {
    font-size: 20px;
    letter-spacing: 0;
}
html[data-lang="en"] .case-title {
    font-size: 24px;
    letter-spacing: 0;
    line-height: 1.3;
}
html[data-lang="en"] .case-list {
    font-size: 16px;
    letter-spacing: 0;
}
html[data-lang="en"] .news-title {
    font-size: 18px;
    letter-spacing: 0;
}
html[data-lang="en"] .footer-col {
    letter-spacing: 0;
}

/* ===================== Responsive tweaks ===================== */
@media (max-width: 1500px) {
    .container { padding: 0 40px; }
}
@media (max-width: 1200px) {
    .section-title { font-size: 38px; }
    .about .section-title { font-size: 42px; }
    .services-grid { grid-template-columns: repeat(2, 1fr); row-gap: 50px; }
    .service-item + .service-item::before { display: none; }
    .cases-grid, .news-grid { grid-template-columns: repeat(2, 1fr); }
    .about-text { font-size: 16px; }
    .service-title { font-size: 24px; }
    .service-list { font-size: 16px; }
    .case-title { font-size: 22px; }
    .news-title { font-size: 18px; }
    .hero-title { font-size: 48px; letter-spacing: 4px; }
    html[data-lang="en"] .hero-title { font-size: 42px; letter-spacing: 1px; }
}
@media (max-width: 720px) {
    .section-title { font-size: 28px; }
    .about .section-title { font-size: 30px; }
    .services-grid, .cases-grid, .news-grid { grid-template-columns: 1fr; }
    .footer-inner { gap: 20px; }
    .section { padding: 60px 0 0; }
    .brand-text, .footer-brand { font-size: 24px; }
    .hero-title { font-size: 26px; letter-spacing: 2px; }
    html[data-lang="en"] .hero-title { font-size: 22px; letter-spacing: 0.5px; }
    .hero-overlay { padding-bottom: 8%; }
}