:root {
    --ink: #17201b;
    --muted: #5f6f68;
    --paper: #fbfaf6;
    --surface: #ffffff;
    --line: #dde6df;
    --brand: #0d9488;
    --brand-dark: #0b5f59;
    --accent: #f97316;
    --blue: #2563eb;
    --charcoal: #0d1512;
    --shadow: 0 24px 70px rgba(12, 40, 33, 0.14);
    --header-height: 72px;
    --radius: 8px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    color: var(--ink);
    background: var(--paper);
    font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

body.menu-open {
    overflow: hidden;
}

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

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

button,
input,
textarea {
    font: inherit;
}

.container {
    width: min(1120px, calc(100% - 40px));
    margin: 0 auto;
}

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 50;
    width: 100%;
    background: rgba(251, 250, 246, 0.88);
    border-bottom: 1px solid rgba(221, 230, 223, 0.76);
    backdrop-filter: blur(18px);
    transition: box-shadow 180ms ease, background 180ms ease;
}

.site-header.scrolled {
    background: rgba(251, 250, 246, 0.96);
    box-shadow: 0 12px 38px rgba(18, 38, 32, 0.08);
}

.header-inner {
    width: min(1180px, calc(100% - 40px));
    height: var(--header-height);
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 28px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    min-width: max-content;
    font-weight: 700;
}

.brand-mark {
    width: 38px;
    height: 38px;
    display: grid;
    place-items: center;
    color: #fff;
    background: linear-gradient(135deg, var(--brand), var(--blue));
    border-radius: 8px;
    box-shadow: 0 12px 30px rgba(13, 148, 136, 0.22);
}

.brand-mark i {
    font-size: 22px;
}

.brand-text {
    font-size: 20px;
    color: var(--ink);
}

.desktop-nav {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;
    flex: 1;
}

.nav-link {
    position: relative;
    color: var(--muted);
    font-size: 15px;
    font-weight: 600;
    padding: 8px 0;
    transition: color 180ms ease;
}

.nav-link::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: 1px;
    height: 2px;
    background: var(--brand);
    transform: scaleX(0);
    transform-origin: center;
    transition: transform 180ms ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--ink);
}

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

.header-domain {
    display: inline-flex;
    align-items: center;
    min-height: 38px;
    padding: 0 14px;
    color: var(--brand-dark);
    border: 1px solid rgba(13, 148, 136, 0.26);
    border-radius: 8px;
    font-size: 14px;
    font-weight: 700;
    background: rgba(255, 255, 255, 0.58);
}

.menu-button {
    display: none;
    width: 42px;
    height: 42px;
    place-items: center;
    border: 1px solid var(--line);
    border-radius: 8px;
    color: var(--ink);
    background: var(--surface);
    cursor: pointer;
}

.menu-button i {
    font-size: 22px;
}

.mobile-nav {
    display: none;
}

.hero {
    position: relative;
    min-height: 88svh;
    padding: calc(var(--header-height) + 88px) 0 84px;
    display: flex;
    align-items: center;
    overflow: hidden;
    background: var(--charcoal);
}

.hero-media {
    position: absolute;
    inset: 0;
    background:
        linear-gradient(90deg, rgba(13, 21, 18, 0.96) 0%, rgba(13, 21, 18, 0.74) 46%, rgba(13, 21, 18, 0.34) 100%),
        url("https://images.unsplash.com/photo-1516321318423-f06f85e504b3?ixlib=rb-4.0.3&auto=format&fit=crop&w=1800&q=86") center right / cover;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 18% 24%, rgba(13, 148, 136, 0.36), transparent 28%),
        linear-gradient(180deg, transparent 0%, rgba(13, 21, 18, 0.68) 100%);
    opacity: 0.92;
}

.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
    background-size: 42px 42px;
    mask-image: linear-gradient(90deg, black 0%, transparent 70%);
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 720px;
    color: #fff;
}

.eyebrow,
.section-kicker {
    margin: 0 0 14px;
    color: var(--accent);
    font-size: 13px;
    font-weight: 800;
    text-transform: uppercase;
}

.hero h1 {
    margin: 0;
    font-family: "Songti SC", "STSong", "Noto Serif CJK SC", serif;
    font-size: clamp(56px, 9vw, 108px);
    line-height: 1.02;
    font-weight: 900;
    letter-spacing: 0;
}

.hero-subtitle {
    width: min(620px, 100%);
    margin: 26px 0 0;
    color: rgba(255, 255, 255, 0.82);
    font-size: 22px;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    margin-top: 34px;
}

.button {
    min-height: 48px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 9px;
    padding: 12px 20px;
    border-radius: 8px;
    font-weight: 800;
    transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease, color 180ms ease;
}

.button:hover {
    transform: translateY(-2px);
}

.button-primary {
    color: #fff;
    background: var(--brand);
    box-shadow: 0 14px 36px rgba(13, 148, 136, 0.28);
}

.button-primary:hover {
    background: #10a99b;
}

.button-secondary {
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.34);
    background: rgba(255, 255, 255, 0.09);
    backdrop-filter: blur(12px);
}

.button-secondary:hover {
    background: rgba(255, 255, 255, 0.16);
}

.hero-proof {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 44px;
}

.hero-proof span {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    color: rgba(255, 255, 255, 0.84);
    border: 1px solid rgba(255, 255, 255, 0.18);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.08);
}

.product-section,
.about-section,
.contact-section {
    padding: 96px 0;
}

.two-column,
.about-layout,
.contact-layout,
.safety-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(320px, 0.86fr);
    gap: 72px;
    align-items: center;
}

.section-copy h2,
.section-header h2,
.safety-panel h2,
.contact-layout h2 {
    margin: 0;
    font-family: "Songti SC", "STSong", "Noto Serif CJK SC", serif;
    font-size: clamp(34px, 4.5vw, 58px);
    line-height: 1.16;
    letter-spacing: 0;
}

.section-copy > p,
.safety-panel > p,
.contact-layout > div:first-child p {
    margin: 22px 0 0;
    color: var(--muted);
    font-size: 17px;
}

.capability-list {
    margin-top: 34px;
    display: grid;
    gap: 18px;
}

.capability-item {
    display: grid;
    grid-template-columns: 44px 1fr;
    gap: 16px;
    align-items: start;
    padding: 18px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.capability-item i {
    width: 44px;
    height: 44px;
    display: grid;
    place-items: center;
    color: var(--brand-dark);
    background: #e7f6f2;
    border-radius: 8px;
    font-size: 22px;
}

.capability-item h3,
.feature-card h3,
.safety-step h3 {
    margin: 0;
    font-size: 18px;
}

.capability-item p,
.feature-card p,
.safety-step p {
    margin: 6px 0 0;
    color: var(--muted);
}

.phone-stage {
    min-height: 560px;
    display: grid;
    place-items: center;
    border-radius: var(--radius);
    background:
        linear-gradient(135deg, rgba(13, 148, 136, 0.12), rgba(249, 115, 22, 0.1)),
        linear-gradient(45deg, transparent 0 48%, rgba(13, 148, 136, 0.16) 48% 52%, transparent 52% 100%);
    background-size: auto, 28px 28px;
    border: 1px solid var(--line);
}

.phone-shell {
    width: min(294px, 78vw);
    aspect-ratio: 9 / 18.5;
    padding: 12px;
    border-radius: 34px;
    background: #111816;
    box-shadow: var(--shadow);
}

.phone-screen {
    height: 100%;
    padding: 18px;
    border-radius: 25px;
    color: #fff;
    background:
        radial-gradient(circle at 24% 18%, rgba(249, 115, 22, 0.44), transparent 28%),
        linear-gradient(180deg, #0b5f59 0%, #0d1512 100%);
    overflow: hidden;
}

.status-line {
    display: flex;
    justify-content: space-between;
    color: rgba(255, 255, 255, 0.76);
    font-size: 13px;
    font-weight: 700;
}

.room-card {
    margin-top: 30px;
    padding: 18px;
    border: 1px solid rgba(255, 255, 255, 0.18);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.12);
}

.room-card div {
    display: flex;
    align-items: center;
    gap: 8px;
    color: rgba(255, 255, 255, 0.76);
    font-size: 13px;
}

.live-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #fb923c;
    box-shadow: 0 0 0 6px rgba(251, 146, 60, 0.18);
}

.room-card strong {
    display: block;
    margin-top: 14px;
    font-size: 24px;
}

.room-card p {
    margin: 4px 0 0;
    color: rgba(255, 255, 255, 0.7);
}

.voice-panel {
    height: 126px;
    margin-top: 26px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 9px;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.08);
}

.voice-panel span {
    width: 11px;
    min-height: 28px;
    border-radius: 999px;
    background: linear-gradient(180deg, #fb923c, #2dd4bf);
    animation: wave 1250ms ease-in-out infinite;
}

.voice-panel span:nth-child(2) {
    animation-delay: 140ms;
}

.voice-panel span:nth-child(3) {
    animation-delay: 280ms;
}

.voice-panel span:nth-child(4) {
    animation-delay: 420ms;
}

.voice-panel span:nth-child(5) {
    animation-delay: 560ms;
}

.mini-rooms {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
    margin-top: 22px;
}

.mini-rooms span {
    min-height: 40px;
    display: grid;
    place-items: center;
    border-radius: 8px;
    color: rgba(255, 255, 255, 0.82);
    background: rgba(255, 255, 255, 0.1);
    font-weight: 700;
}

.join-room {
    width: 100%;
    min-height: 48px;
    margin-top: 22px;
    border: 0;
    border-radius: 8px;
    color: #0d1512;
    background: #fff;
    font-weight: 900;
}

@keyframes wave {
    0%,
    100% {
        height: 34px;
    }
    50% {
        height: 86px;
    }
}

.feature-band {
    padding: 92px 0;
    color: #fff;
    background: #0d1512;
}

.section-header {
    width: min(760px, 100%);
    margin-bottom: 42px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 18px;
}

.feature-card {
    min-height: 248px;
    padding: 24px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: var(--radius);
    background: rgba(255, 255, 255, 0.06);
}

.feature-card i {
    width: 46px;
    height: 46px;
    display: grid;
    place-items: center;
    margin-bottom: 28px;
    color: #fff;
    background: rgba(13, 148, 136, 0.72);
    border-radius: 8px;
    font-size: 23px;
}

.feature-card p {
    color: rgba(255, 255, 255, 0.68);
}

.safety-section {
    padding: 96px 0;
    background: #edf6f2;
}

.safety-layout {
    grid-template-columns: minmax(0, 0.92fr) minmax(340px, 1fr);
}

.safety-panel {
    padding: 36px;
    border-left: 5px solid var(--brand);
    background: rgba(255, 255, 255, 0.68);
}

.safety-steps {
    display: grid;
    gap: 16px;
}

.safety-step {
    display: grid;
    grid-template-columns: 62px 1fr;
    gap: 18px;
    padding: 24px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.safety-step span {
    color: var(--accent);
    font-family: Georgia, "Times New Roman", serif;
    font-size: 28px;
    line-height: 1;
    font-weight: 800;
}

.about-layout {
    grid-template-columns: minmax(320px, 0.9fr) minmax(0, 1fr);
}

.about-image {
    position: relative;
}

.about-image::before {
    content: "";
    position: absolute;
    inset: 22px -22px -22px 22px;
    border: 1px solid var(--brand);
    border-radius: var(--radius);
    z-index: -1;
}

.about-image img {
    aspect-ratio: 5 / 4;
    object-fit: cover;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.company-info {
    margin: 34px 0 0;
    display: grid;
    gap: 12px;
}

.company-info div {
    display: grid;
    grid-template-columns: 92px 1fr;
    gap: 18px;
    padding: 16px 0;
    border-bottom: 1px solid var(--line);
}

.company-info dt {
    color: var(--muted);
    font-weight: 700;
}

.company-info dd {
    margin: 0;
    font-weight: 800;
}

.contact-section {
    background: #fff;
}

.contact-layout {
    grid-template-columns: minmax(0, 1fr) minmax(320px, 430px);
}

.contact-card {
    display: grid;
    gap: 16px;
    padding: 28px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--paper);
    box-shadow: 0 18px 54px rgba(23, 32, 27, 0.08);
}

.contact-row {
    display: grid;
    grid-template-columns: 44px 1fr;
    gap: 14px;
    align-items: center;
    min-width: 0;
}

.contact-row i {
    width: 44px;
    height: 44px;
    display: grid;
    place-items: center;
    color: var(--brand-dark);
    background: #e7f6f2;
    border-radius: 8px;
    font-size: 22px;
}

.contact-row span {
    display: block;
    color: var(--muted);
    font-size: 13px;
    font-weight: 700;
}

.contact-row a,
.contact-row strong {
    display: block;
    min-width: 0;
    color: var(--ink);
    overflow-wrap: anywhere;
    font-weight: 900;
}

.site-footer {
    color: rgba(255, 255, 255, 0.72);
    background: #0d1512;
}

.footer-inner {
    min-height: 128px;
    display: flex;
    justify-content: space-between;
    gap: 24px;
    align-items: center;
}

.footer-brand .brand-text {
    color: #fff;
}

.footer-brand p {
    margin: 12px 0 0;
}

.footer-legal {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 10px 18px;
    text-align: right;
}

.footer-legal a {
    color: rgba(255, 255, 255, 0.88);
    text-decoration: underline;
    text-underline-offset: 4px;
}

@media (max-width: 980px) {
    .desktop-nav,
    .header-domain {
        display: none;
    }

    .header-inner {
        justify-content: space-between;
    }

    .menu-button {
        display: grid;
    }

    .mobile-nav {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        display: grid;
        gap: 4px;
        padding: 16px 20px 24px;
        background: rgba(251, 250, 246, 0.98);
        border-bottom: 1px solid var(--line);
        box-shadow: 0 18px 42px rgba(18, 38, 32, 0.12);
        transform: translateY(-18px);
        opacity: 0;
        pointer-events: none;
        transition: transform 180ms ease, opacity 180ms ease;
    }

    .mobile-nav.open {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }

    .mobile-nav a {
        padding: 14px 4px;
        color: var(--ink);
        border-bottom: 1px solid var(--line);
        font-weight: 800;
    }

    .two-column,
    .about-layout,
    .contact-layout,
    .safety-layout {
        grid-template-columns: 1fr;
        gap: 44px;
    }

    .about-image {
        order: 2;
    }

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

@media (max-width: 680px) {
    :root {
        --header-height: 66px;
    }

    .container,
    .header-inner {
        width: min(100% - 28px, 1120px);
    }

    .brand-text {
        font-size: 18px;
    }

    .hero {
        min-height: 86svh;
        padding: calc(var(--header-height) + 62px) 0 58px;
    }

    .hero-media {
        background:
            linear-gradient(180deg, rgba(13, 21, 18, 0.86) 0%, rgba(13, 21, 18, 0.8) 62%, rgba(13, 21, 18, 0.96) 100%),
            url("https://images.unsplash.com/photo-1516321318423-f06f85e504b3?ixlib=rb-4.0.3&auto=format&fit=crop&w=980&q=82") center / cover;
    }

    .hero h1 {
        font-size: 58px;
    }

    .hero-subtitle {
        font-size: 18px;
    }

    .hero-actions {
        flex-direction: column;
    }

    .button {
        width: 100%;
    }

    .hero-proof {
        gap: 8px;
    }

    .product-section,
    .about-section,
    .contact-section,
    .safety-section,
    .feature-band {
        padding: 68px 0;
    }

    .section-copy h2,
    .section-header h2,
    .safety-panel h2,
    .contact-layout h2 {
        font-size: 34px;
    }

    .phone-stage {
        min-height: 470px;
    }

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

    .feature-card {
        min-height: 210px;
    }

    .safety-panel,
    .contact-card {
        padding: 22px;
    }

    .safety-step,
    .capability-item {
        grid-template-columns: 1fr;
    }

    .company-info div {
        grid-template-columns: 1fr;
        gap: 4px;
    }

    .about-image::before {
        display: none;
    }

    .footer-inner {
        padding: 32px 0;
        align-items: flex-start;
        flex-direction: column;
    }

    .footer-legal {
        justify-content: flex-start;
        text-align: left;
    }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        animation-duration: 1ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 1ms !important;
    }
}