:root {
    --ink: #252525;
    --muted: #777;
    --bg: #f2f2f2;
    --panel: #fff;
    --dark: #2f2f2f;
    --accent: #f6a61d;
    --warm: #f7e3bd;
    --gutter: var(--site-gutter, clamp(32px, 5.2vw, 132px));
    --max: 1320px;
    --radius: 8px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    color: var(--ink);
    background: var(--bg);
    font-family: SimHei, "Heiti SC", STHeiti, "Microsoft YaHei", Arial, sans-serif;
    line-height: 1.6;
}

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

img,
video {
    display: block;
    max-width: 100%;
}

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 50;
    background: rgba(36, 36, 36, .94);
    color: #fff;
    border-bottom: 1px solid rgba(255, 255, 255, .08);
}

.nav-shell {
    width: calc(100% - 96px);
    height: 74px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 30px;
}

.brand {
    display: inline-flex;
    min-width: 132px;
}

.brand img {
    width: 132px;
    height: auto;
}

.nav-links {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: clamp(18px, 2.6vw, 48px);
}

.nav-links a {
    position: relative;
    color: rgba(255, 255, 255, .86);
    font-size: 14px;
    white-space: nowrap;
}

.nav-links a.is-active,
.nav-links a:hover {
    color: var(--accent);
}

.nav-links a.is-active::after,
.nav-links a:hover::after {
    transform: scaleX(1);
}

.nav-links a::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -12px;
    height: 2px;
    background: var(--accent);
    transform: scaleX(0);
    transition: transform .2s ease;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.lang-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: rgba(255, 255, 255, .82);
    font-size: 12px;
}

.lang-link::before {
    content: "";
    width: 13px;
    height: 13px;
    border: 1px solid currentColor;
    border-radius: 50%;
}

.pill {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 38px;
    padding: 0 20px;
    border-radius: 999px;
    background: var(--accent);
    color: #242424;
    border-radius: 2px;
    font-size: 14px;
    font-weight: 800;
    white-space: nowrap;
}

.menu-toggle {
    display: none;
    width: 42px;
    height: 42px;
    border: 1px solid rgba(255, 255, 255, .2);
    border-radius: var(--radius);
    background: transparent;
    color: #fff;
    cursor: pointer;
}

.menu-toggle span {
    display: block;
    width: 18px;
    height: 2px;
    margin: 4px auto;
    background: currentColor;
}

main {
    overflow: hidden;
}

.hero {
    padding-top: 74px;
    background: #000;
    cursor: pointer;
}

.hero-bg {
    width: 100%;
    height: clamp(280px, 39vw, 760px);
    object-fit: cover;
    object-position: center top;
}

.hero.is-video-expanded {
    padding-top: 0;
    background: #000;
}

.hero.is-video-expanded .hero-bg {
    height: auto;
    object-fit: fill;
}

.hero:fullscreen {
    width: 100vw;
    height: 100vh;
    padding-top: 0;
    display: grid;
    place-items: center;
    background: #000;
}

.hero:fullscreen .hero-bg {
    width: 100vw;
    height: 100vh;
    object-fit: contain;
}

.product-hero {
    padding: 42px var(--gutter) 88px;
    text-align: center;
    background: linear-gradient(180deg, #f6dfb8 0%, #f2f2f2 72%, #f2f2f2 100%);
}

.product-hero h1 {
    margin: 0;
    font-size: clamp(34px, 4.4vw, 70px);
    line-height: 1.15;
    font-weight: 900;
}

.section {
    padding: clamp(72px, 8vw, 132px) var(--gutter);
}

.section > * {
    max-width: none;
    margin-left: 0;
    margin-right: 0;
}

.section > :not(.section-label) {
    margin-left: 1em;
    max-width: calc(100% - 1em);
}

.section-label {
    position: relative;
    z-index: 1;
    display: inline-block;
    max-width: none;
    margin-left: 0;
    margin-right: 0;
    margin-bottom: clamp(34px, 4vw, 58px);
    padding-left: 0;
    font-size: clamp(20px, 1.8vw, 30px);
    font-weight: 900;
    line-height: 1.1;
    isolation: isolate;
}

.section-label::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    z-index: -1;
    width: 10px;
    height: 34px;
    background: var(--accent);
    transform: translate(-2px, -50%) skew(-14deg);
}

.intro-layout {
    display: grid;
    grid-template-columns: minmax(280px, 40%) 1fr;
    justify-content: space-between;
}

.intro-copy h2,
.warm-section h2,
.app-demo h2,
.install-layout h2,
.models-head h2 {
    margin: 0 0 22px;
    font-size: clamp(28px, 3vw, 52px);
    line-height: 1.18;
    font-weight: 900;
}

.intro-copy p,
.section-lead,
.app-demo p,
.install-layout p,
.models-head p {
    margin: 0 0 18px;
    color: var(--muted);
    font-size: clamp(15px, 1vw, 18px);
}

.intro-stats-img {
    width: min(693px, 100%);
    margin-top: 34px;
}

.image-card-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 40%));
    gap: clamp(28px, 4vw, 56px);
    margin-top: 86px;
    justify-content: space-between;
}

.image-card,
.tech-card,
.model-grid article,
.service-grid article {
    min-width: 0;
}

.image-card img,
.tech-card img {
    width: 100%;
    border-radius: 5px;
}

.image-card h3,
.tech-card h3,
.phone-grid h3,
.model-grid h3,
.service-grid h3 {
    margin: 20px 0 8px;
    font-size: clamp(18px, 1.4vw, 24px);
    line-height: 1.25;
}

.tech-card h3 {
    display: flex;
    align-items: center;
    gap: 10px;
}

.title-index {
    display: inline-grid;
    place-items: center;
    flex: 0 0 auto;
    width: 22px;
    height: 22px;
    background: var(--accent);
    color: #242424;
    font-size: 14px;
    font-weight: 900;
    line-height: 1;
}

.image-card p,
.tech-card p,
.phone-grid p,
.service-grid p,
.model-grid p,
.model-grid span {
    margin: 0;
    color: var(--muted);
    font-size: 14px;
}

.image-card p,
.tech-card p {
    white-space: pre-line;
}

.warm-section {
    background: linear-gradient(180deg, #f6dfb8 0%, #f2f2f2 24%, #f2f2f2 100%);
}

.custom-section {
    background: #fff;
}

.section-lead {
    max-width: 760px;
    margin-left: 0;
}

.section-lead p {
    margin: 0 0 18px;
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 40%));
    gap: clamp(34px, 5vw, 70px);
    margin-top: 54px;
    justify-content: space-between;
}

.app-section {
    background: #fff;
}

.app-section .section-label {
    margin-bottom: clamp(17px, 2vw, 29px);
}

.app-video {
    width: 100%;
    aspect-ratio: 16 / 7;
    margin-bottom: 28px;
    background: #000;
    object-fit: cover;
    border-radius: 18px;
}

.app-layout {
    position: relative;
    display: block;
    min-height: clamp(520px, 44vw, 820px);
}

.hand-phone {
    position: absolute;
    z-index: 1;
    top: clamp(22px, 3vw, 54px);
    right: 0;
    width: min(420px, 34%);
    max-width: none;
}

.app-demo {
    position: relative;
    z-index: 2;
    width: 58%;
}

.phone-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 22px;
    margin-top: 46px;
    justify-content: space-between;
}

.phone-grid img {
    width: 100%;
    max-height: 450px;
    object-fit: contain;
}

.phone-grid article {
    text-align: center;
}

.install-layout {
    display: grid;
    grid-template-columns: minmax(320px, 40%) minmax(320px, 40%);
    align-items: center;
    gap: clamp(30px, 6vw, 90px);
    justify-content: space-between;
}

.install-section {
    background: #fff;
}

.install-images {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(120px, 32%);
    align-items: stretch;
    gap: clamp(16px, 2vw, 28px);
}

.install-images img {
    width: 100%;
}

.install-main {
    height: 100%;
    object-fit: contain;
}

.install-details {
    display: grid;
    grid-template-rows: 1fr 1fr;
    gap: clamp(14px, 1.8vw, 24px);
    height: 100%;
}

.install-detail {
    display: flex;
    flex-direction: column;
    margin: 0;
    min-height: 0;
}

.install-detail img {
    width: 100%;
    flex: 1;
    min-height: 0;
    object-fit: cover;
}

.install-detail figcaption {
    margin-top: 10px;
    color: var(--muted);
    font-size: clamp(13px, 0.9vw, 16px);
    line-height: 1.5;
}

.install-detail figcaption strong {
    display: block;
    color: var(--ink, inherit);
    font-weight: 700;
}

.custom-layout {
    display: grid;
    grid-template-columns: 26% 1fr;
    align-items: start;
    gap: 5%;
    justify-content: space-between;
}

.custom-copy {
    padding-top: clamp(18px, 4vw, 62px);
}

.custom-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 18px;
    margin-top: 42px;
}

.custom-tags span {
    position: relative;
    display: grid;
    place-items: center;
    width: 68px;
    aspect-ratio: 1;
    color: #777;
    font-size: 14px;
    font-weight: 800;
}

.custom-tags img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.custom-tags b {
    position: relative;
    z-index: 1;
    font: inherit;
}

.model-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 7%;
    margin-top: 0;
    justify-content: space-between;
}

.model-grid article {
    padding: 0;
    background: transparent;
    box-shadow: none;
}

.model-grid img {
    width: 100%;
    aspect-ratio: 1;
    object-fit: contain;
}

.model-grid h3 {
    margin-top: 24px;
    width: fit-content;
    max-width: 100%;
    color: var(--ink);
    background-image: linear-gradient(var(--accent), var(--accent));
    background-repeat: no-repeat;
    background-size: 100% 7px;
    background-position: 0 calc(100% - 7px);
    padding: 0 8px 1px;
}

.model-grid .model-stars {
    color: var(--accent);
    font-weight: 400;
    letter-spacing: 1px;
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 44%));
    gap: 7%;
    margin-top: clamp(80px, 9vw, 150px);
    justify-content: space-between;
}

.service-grid article {
    position: relative;
    min-height: clamp(300px, 24vw, 430px);
    padding: clamp(34px, 4vw, 62px);
    background: #e9e9e9;
    border-radius: 14px;
    box-shadow: none;
}

.service-grid img {
    position: absolute;
    top: clamp(34px, 4vw, 58px);
    right: clamp(36px, 4vw, 64px);
    width: clamp(64px, 7vw, 112px);
    height: clamp(64px, 7vw, 112px);
    object-fit: contain;
    opacity: .65;
}

.service-grid strong {
    display: block;
    margin: clamp(52px, 7vw, 92px) 0 24px;
    font-size: clamp(24px, 2.6vw, 42px);
    line-height: 1.2;
}

.service-grid h3 {
    position: relative;
    z-index: 1;
    display: inline-block;
    isolation: isolate;
}

.service-grid h3::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    z-index: -1;
    width: 10px;
    height: 34px;
    background: var(--accent);
    transform: translate(-2px, -50%) skew(-14deg);
    border-radius: 2px;
}

.service-grid p + p {
    margin-top: 8px;
}

.cases-section .case-stage {
    display: grid;
    grid-template-columns: minmax(220px, 1fr) minmax(520px, 2.55fr) minmax(220px, 1fr);
    gap: 24px;
    align-items: stretch;
    width: calc(100vw - 2 * var(--gutter));
    height: clamp(330px, 31vw, 520px);
    margin-left: 0;
}

.cases-section .case-stage + .case-caption {
    margin-bottom: clamp(54px, 6vw, 90px);
}

.cases-section .case-caption:last-child {
    margin-bottom: 0;
}

.case-card {
    min-height: 0;
    height: 100%;
    border-radius: var(--radius);
    overflow: hidden;
    background: #ededed;
    position: relative;
    margin: 0;
}

.case-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    background: #ededed;
}

.case-card.featured {
    height: 100%;
}

.case-caption {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 48px;
    margin-top: 36px;
}

.case-arrow {
    width: 58px;
    height: 58px;
    border-radius: 50%;
    border: 1px solid rgba(36, 36, 36, .08);
    background: rgba(255, 255, 255, .55);
    color: rgba(36, 36, 36, .35);
    font-size: 34px;
    cursor: pointer;
}

.case-caption strong {
    min-width: 180px;
    text-align: center;
    font-size: 28px;
    line-height: 1.2;
}

.site-footer {
    background: var(--bg);
}

.copyright {
    width: min(var(--max), calc(100% - 48px));
    margin: 0 auto;
    padding: 0 0 30px;
    color: rgba(36, 36, 36, .58);
    font-size: 13px;
    line-height: 1.8;
    text-align: center;
}

@media (max-width: 1080px) {
    .nav-shell {
        width: calc(100% - 48px);
    }

    .nav-links {
        gap: 16px;
    }

    .intro-layout,
    .app-layout,
    .install-layout {
        grid-template-columns: 1fr;
    }

    .app-layout {
        display: grid;
        min-height: 0;
    }

    .app-demo {
        width: 100%;
    }

    .hand-phone {
        position: static;
        justify-self: center;
        width: min(420px, 100%);
    }

    .phone-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 820px) {
    .nav-shell {
        height: 66px;
        width: calc(100% - 32px);
    }

    .brand {
        min-width: 126px;
    }

    .brand img {
        width: 126px;
    }

    .nav-links {
        position: absolute;
        top: 66px;
        left: 16px;
        right: 16px;
        display: none;
        grid-template-columns: 1fr;
        justify-content: stretch;
        gap: 0;
        padding: 10px;
        background: rgba(45, 45, 45, .98);
        border: 1px solid rgba(255, 255, 255, .1);
        border-radius: var(--radius);
    }

    .site-header.is-open .nav-links {
        display: grid;
    }

    .nav-links a {
        padding: 12px 10px;
    }

    .nav-actions .pill {
        display: none;
    }

    .menu-toggle {
        display: block;
    }

    .hero {
        padding-top: 66px;
        cursor: default;
    }

    .hero-bg {
        width: 100%;
        height: min(56.25vw, 360px);
        min-height: 0;
        object-fit: cover;
        object-position: center top;
    }

    .product-hero {
        padding: 28px var(--gutter) 54px;
    }

    .image-card-grid,
    .tech-grid,
    .model-grid,
    .service-grid {
        grid-template-columns: 1fr;
    }

    .cases-section .case-stage {
        grid-template-columns: minmax(0, 1fr);
        width: min(var(--max), calc(100% - 48px));
        height: auto;
        margin-left: auto;
        margin-right: auto;
        padding: 0;
    }

    .case-card:not(.featured) {
        display: none;
    }

    .custom-layout {
        grid-template-columns: 1fr;
    }

    .intro-layout,
    .install-layout,
    .custom-layout {
        gap: 34px;
    }

    .image-card-grid,
    .tech-grid {
        gap: 38px;
        margin-top: 42px;
    }

    .intro-copy h2,
    .warm-section h2,
    .app-demo h2,
    .install-layout h2,
    .models-head h2 {
        font-size: clamp(24px, 7vw, 34px);
    }

    .intro-copy p,
    .section-lead,
    .app-demo p,
    .install-layout p,
    .models-head p,
    .image-card p,
    .tech-card p,
    .phone-grid p,
    .service-grid p,
    .model-grid p,
    .model-grid span {
        font-size: 14px;
        line-height: 1.75;
    }

    .intro-stats-img,
    .image-card img,
    .tech-card img,
    .install-images,
    .model-grid img {
        width: 100%;
        height: auto;
    }

    .app-layout {
        gap: 24px;
    }

    .app-video {
        width: 100%;
        height: min(56.25vw, 320px);
        aspect-ratio: auto;
        margin-bottom: 18px;
        object-fit: cover;
    }

    .hand-phone {
        width: min(78vw, 360px);
        margin: 0 auto;
    }

    .install-images {
        grid-template-columns: minmax(0, 1fr);
        gap: 16px;
    }

    .install-main,
    .install-detail img {
        height: auto;
        object-fit: contain;
    }

    .install-details {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        grid-template-rows: none;
        height: auto;
    }

    .custom-copy {
        padding-top: 0;
    }

    .custom-tags {
        gap: 12px;
        margin-top: 24px;
    }

    .model-grid {
        gap: 36px;
    }

    .service-grid {
        gap: 24px;
        margin-top: 54px;
    }

    .service-grid article {
        min-height: 0;
        padding: 28px 24px;
        border-radius: 10px;
    }

    .service-grid img {
        position: static;
        width: 64px;
        height: 64px;
        margin-left: auto;
    }

    .service-grid strong {
        margin: 18px 0 16px;
        font-size: clamp(22px, 6vw, 30px);
    }
}

@media (max-width: 560px) {
    :root {
        --gutter: 16px;
    }

    .section {
        padding-top: 54px;
        padding-bottom: 54px;
    }

    .section > :not(.section-label) {
        margin-left: 0;
        max-width: none;
    }

    .product-hero h1 {
        font-size: clamp(28px, 8vw, 36px);
    }

    .section-label {
        margin-bottom: 28px;
        font-size: 22px;
    }

    .image-card h3,
    .tech-card h3,
    .phone-grid h3,
    .model-grid h3,
    .service-grid h3 {
        font-size: 18px;
    }

    .phone-grid {
        grid-template-columns: 1fr;
        gap: 28px;
        margin-top: 32px;
    }

    .phone-grid img {
        width: min(76vw, 290px);
        max-height: none;
        margin: 0 auto;
    }

    .phone-grid article {
        text-align: left;
    }

    .phone-grid h3,
    .phone-grid p {
        width: min(76vw, 290px);
        margin-left: auto;
        margin-right: auto;
    }

    .cases-section .case-stage {
        width: calc(100% - 32px);
    }

    .case-card,
    .case-card.featured {
        height: auto;
        aspect-ratio: 16 / 10;
    }

    .case-caption {
        gap: 16px;
        margin-top: 26px;
    }

}