:root {
    --ink: #111512;
    --ink-soft: #27312b;
    --muted: #66716a;
    --paper: #f1f4f1;
    --paper-strong: #e5eae6;
    --white: #ffffff;
    --line: #cfd7d1;
    --blue: #075ea8;
    --blue-dark: #073f70;
    --forest: #123235;
    --signal: #b8ef4a;
    --error: #a12323;
    --success: #23643b;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    color: var(--ink);
    background: var(--white);
    font-family: "Aptos", "Segoe UI", sans-serif;
    font-size: 16px;
    line-height: 1.55;
}

.site-language-zh {
    font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", sans-serif;
}

body,
button,
input,
select,
textarea {
    letter-spacing: 0;
}

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

a {
    color: inherit;
}

button,
input,
select,
textarea {
    font: inherit;
}

button,
a,
input,
select,
textarea,
summary {
    outline-offset: 3px;
}

:focus-visible {
    outline: 3px solid var(--signal);
}

.site-shell {
    width: min(100% - 48px, 1280px);
    margin-inline: auto;
}

.eyebrow {
    margin: 0 0 16px;
    color: var(--blue);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 13px;
    font-weight: 700;
    line-height: 1.2;
    text-transform: uppercase;
}

h1,
h2,
h3,
p {
    overflow-wrap: anywhere;
}

h1,
h2,
h3 {
    margin: 0;
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-weight: 700;
    letter-spacing: 0;
}

h1 {
    font-size: 72px;
    line-height: 1.02;
}

.site-language-zh h1 {
    font-size: 64px;
    line-height: 1.08;
}

h2 {
    font-size: 46px;
    line-height: 1.08;
}

h3 {
    font-size: 20px;
    line-height: 1.2;
}

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0 20px;
    border: 1px solid transparent;
    border-radius: 5px;
    cursor: pointer;
    font-weight: 700;
    text-decoration: none;
    transition: background-color 180ms ease-out, border-color 180ms ease-out, color 180ms ease-out, transform 180ms ease-out;
}

.button:hover {
    transform: translateY(-1px);
}

.button--primary {
    color: var(--white);
    background: var(--blue);
}

.button--primary:hover {
    background: var(--blue-dark);
}

.button--outline {
    color: var(--ink);
    background: transparent;
    border-color: var(--ink);
}

.button--outline:hover {
    color: var(--white);
    background: var(--ink);
}

.button--text {
    gap: 10px;
    min-height: 48px;
    padding: 0 4px;
    color: var(--ink);
    border-radius: 0;
}

.button--text span {
    color: var(--blue);
    font-size: 22px;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.96);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(14px);
}

.site-header__inner {
    display: grid;
    grid-template-columns: minmax(210px, 1fr) auto minmax(250px, 1fr);
    align-items: center;
    gap: 32px;
    width: min(100% - 48px, 1280px);
    min-height: 74px;
    margin-inline: auto;
}

.site-brand,
.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    width: fit-content;
    text-decoration: none;
}

.site-brand__mark {
    display: block;
    flex: 0 0 auto;
    width: 42px;
    height: 42px;
    border-radius: 4px;
}

.site-brand__copy strong,
.site-brand__copy small,
.footer-brand strong,
.footer-brand small {
    display: block;
}

.site-brand__copy strong,
.footer-brand strong {
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 16px;
    line-height: 1.1;
}

.site-brand__copy small {
    margin-top: 3px;
    color: var(--muted);
    font-size: 11px;
}

.site-nav {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 26px;
}

.site-nav a {
    color: var(--ink-soft);
    font-size: 14px;
    font-weight: 600;
    text-decoration: none;
}

.site-nav a:hover {
    color: var(--blue);
}

.site-header__actions {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 10px;
}

.language-switcher {
    display: inline-flex;
    align-items: center;
    min-height: 42px;
    padding: 3px;
    background: var(--paper);
    border: 1px solid var(--line);
    border-radius: 5px;
}

.language-switcher a {
    display: inline-grid;
    place-items: center;
    min-width: 42px;
    height: 34px;
    padding-inline: 8px;
    border-radius: 3px;
    color: var(--ink-soft);
    font-size: 12px;
    font-weight: 700;
    text-decoration: none;
}

.language-switcher a.is-active {
    color: var(--white);
    background: var(--ink);
}

.header-cta {
    min-height: 42px;
    padding-inline: 16px;
    font-size: 13px;
}

.nav-toggle {
    display: none;
    width: 44px;
    height: 44px;
    padding: 11px 9px;
    background: transparent;
    border: 1px solid var(--line);
    border-radius: 4px;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    height: 2px;
    margin: 4px 0;
    background: var(--ink);
}

.hero-section {
    position: relative;
    overflow: hidden;
    padding: 72px 0 84px;
    background: var(--paper);
}

.hero-section::after {
    content: "FILTER SYSTEMS / MODEL INDEX";
    position: absolute;
    right: -36px;
    bottom: 18px;
    color: #d9dfda;
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 68px;
    font-weight: 700;
    line-height: 1;
    pointer-events: none;
    white-space: nowrap;
}

.hero-layout {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(430px, 0.8fr);
    gap: 76px;
    align-items: center;
}

.hero-copy {
    max-width: 760px;
}

.hero-lead {
    max-width: 650px;
    margin: 28px 0 0;
    color: var(--ink-soft);
    font-size: 19px;
    line-height: 1.65;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 24px;
    align-items: center;
    margin-top: 34px;
}

.hero-product__frame {
    position: relative;
    min-height: 570px;
    padding: 48px 32px 128px;
    background: var(--white);
    border: 1px solid var(--line);
}

.hero-product__frame::before {
    content: "";
    position: absolute;
    top: -12px;
    right: 24px;
    width: 92px;
    height: 24px;
    background: var(--signal);
}

.frame-index {
    position: absolute;
    top: 20px;
    left: 20px;
    color: var(--muted);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 11px;
    font-weight: 700;
}

.hero-product__frame img {
    width: 100%;
    height: 390px;
    object-fit: contain;
    mix-blend-mode: multiply;
}

.hero-product__caption {
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 2px 20px;
    padding: 22px 26px;
    color: var(--white);
    background: var(--ink);
}

.hero-product__caption small {
    grid-row: 1 / 3;
    align-self: center;
    color: var(--signal);
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
}

.hero-product__caption strong {
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 24px;
}

.hero-product__caption span {
    color: #cbd2cd;
    font-size: 13px;
}

.proof-strip {
    color: var(--white);
    background: var(--ink);
}

.proof-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
}

.proof-item {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 14px;
    align-items: center;
    min-height: 108px;
    padding: 18px 28px;
    border-left: 1px solid #364039;
}

.proof-item:last-child {
    border-right: 1px solid #364039;
}

.proof-item strong {
    color: var(--signal);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 34px;
    line-height: 1;
}

.proof-item span {
    color: #d5ddd7;
    font-size: 13px;
}

.catalog-section,
.quality-section,
.rfq-section,
.related-products,
.detail-scope {
    padding: 100px 0;
}

.section-intro {
    display: grid;
    grid-template-columns: minmax(0, 0.9fr) minmax(340px, 0.52fr);
    gap: 72px;
    align-items: end;
    margin-bottom: 44px;
}

.section-intro p:last-child {
    margin: 0;
    color: var(--muted);
    font-size: 17px;
}

.catalog-toolbar {
    display: grid;
    grid-template-columns: minmax(300px, 0.65fr) minmax(0, 1fr);
    gap: 28px;
    align-items: end;
    padding: 22px 0;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.catalog-search span {
    display: block;
    margin-bottom: 8px;
    color: var(--muted);
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
}

.catalog-search input {
    width: 100%;
    height: 48px;
    padding: 0 16px;
    color: var(--ink);
    background: var(--paper);
    border: 1px solid transparent;
    border-radius: 4px;
}

.catalog-search input:focus {
    background: var(--white);
    border-color: var(--blue);
}

.catalog-filters {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: flex-end;
}

.catalog-filters button {
    min-height: 40px;
    padding: 0 12px;
    color: var(--ink-soft);
    background: transparent;
    border: 1px solid var(--line);
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
    font-weight: 700;
}

.catalog-filters button:hover,
.catalog-filters button.is-active {
    color: var(--white);
    background: var(--ink);
    border-color: var(--ink);
}

.catalog-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 42px 22px;
    margin-top: 42px;
}

.catalog-card {
    min-width: 0;
    border-top: 3px solid var(--ink);
}

.catalog-card[hidden],
.catalog-card.is-collapsed {
    display: none;
}

.catalog-card__image {
    position: relative;
    display: block;
    aspect-ratio: 1 / 1;
    overflow: hidden;
    background: var(--paper);
}

.catalog-card__image img {
    width: 100%;
    height: 100%;
    padding: 22px;
    object-fit: contain;
    mix-blend-mode: multiply;
    transition: transform 220ms ease-out;
}

.catalog-card__image:hover img {
    transform: scale(1.035);
}

.catalog-card__image > span {
    position: absolute;
    top: 12px;
    left: 12px;
    min-width: 38px;
    padding: 5px 7px;
    color: var(--white);
    background: var(--blue);
    border-radius: 2px;
    font-size: 11px;
    font-weight: 700;
    text-align: center;
}

.catalog-card__body {
    padding-top: 16px;
}

.catalog-card__codes {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    padding-bottom: 11px;
    color: var(--muted);
    border-bottom: 1px solid var(--line);
    font-size: 11px;
    text-transform: uppercase;
}

.catalog-card__codes strong {
    color: var(--ink);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
}

.catalog-card h3 {
    min-height: 48px;
    margin-top: 14px;
}

.catalog-card h3 a {
    text-decoration: none;
}

.catalog-card h3 a:hover {
    color: var(--blue);
}

.catalog-card__body > p {
    min-height: 44px;
    margin: 9px 0 0;
    color: var(--muted);
    font-size: 13px;
}

.catalog-card__link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 16px;
    color: var(--blue);
    font-size: 13px;
    font-weight: 700;
    text-decoration: none;
}

.catalog-card__link span {
    font-size: 20px;
}

.catalog-more {
    display: flex;
    margin: 44px auto 0;
}

.catalog-more[hidden],
.catalog-empty[hidden] {
    display: none;
}

.catalog-empty {
    padding: 36px;
    margin: 36px 0 0;
    color: var(--muted);
    background: var(--paper);
    border-left: 4px solid var(--blue);
}

.trademark-note {
    max-width: 920px;
    margin: 26px 0 0;
    color: var(--muted);
    font-size: 12px;
}

.oem-section {
    padding: 100px 0;
    color: var(--white);
    background: var(--forest);
}

.oem-layout {
    display: grid;
    grid-template-columns: minmax(300px, 0.7fr) minmax(0, 1.3fr);
    gap: 64px 80px;
}

.oem-copy .eyebrow,
.section-intro--light .eyebrow {
    color: var(--signal);
}

.oem-copy p:last-child {
    margin: 24px 0 0;
    color: #cbd7d2;
    font-size: 17px;
}

.oem-visual {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
}

.oem-visual figure {
    position: relative;
    min-width: 0;
    margin: 0;
    background: var(--white);
}

.oem-visual img {
    width: 100%;
    aspect-ratio: 0.82 / 1;
    padding: 18px;
    object-fit: contain;
}

.oem-visual figcaption {
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    padding: 8px 10px;
    color: var(--white);
    background: rgba(17, 21, 18, 0.88);
    font-size: 10px;
    font-weight: 700;
}

.oem-steps {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0;
    padding: 0;
    margin: 0;
    list-style: none;
    border-top: 1px solid #42605a;
    border-bottom: 1px solid #42605a;
}

.oem-steps li {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 16px;
    padding: 28px 24px;
    border-right: 1px solid #42605a;
}

.oem-steps li:last-child {
    border-right: 0;
}

.oem-steps li > span {
    color: var(--signal);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 13px;
    font-weight: 700;
}

.oem-steps p {
    margin: 8px 0 0;
    color: #bdcac4;
    font-size: 13px;
}

.quality-section {
    color: var(--white);
    background: var(--ink);
}

.section-intro--light p:last-child {
    color: #bfc8c2;
}

.quality-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    border-top: 1px solid #3d4640;
    border-bottom: 1px solid #3d4640;
}

.quality-grid article {
    min-height: 240px;
    padding: 28px 24px;
    border-right: 1px solid #3d4640;
}

.quality-grid article:last-child {
    border-right: 0;
}

.quality-grid article > span {
    color: var(--signal);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 13px;
    font-weight: 700;
}

.quality-grid h3 {
    margin-top: 46px;
}

.quality-grid p {
    margin: 12px 0 0;
    color: #bfc8c2;
    font-size: 14px;
}

.rfq-section {
    background: var(--paper);
}

.rfq-layout {
    display: grid;
    grid-template-columns: minmax(300px, 0.7fr) minmax(0, 1fr);
    gap: 80px;
    align-items: start;
}

.rfq-intro {
    position: sticky;
    top: 112px;
}

.rfq-intro > p:last-of-type {
    margin: 24px 0 0;
    color: var(--muted);
    font-size: 17px;
}

.rfq-index {
    margin-top: 80px;
    color: #d4dad5;
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 74px;
    font-weight: 700;
    line-height: 1;
}

.rfq-form-wrap {
    padding: 36px;
    background: var(--white);
    border-top: 4px solid var(--blue);
}

.form-notice {
    padding: 14px 16px;
    margin-bottom: 24px;
    border-left: 4px solid;
    font-weight: 600;
}

.form-notice--success {
    color: var(--success);
    background: #eaf6ee;
    border-color: var(--success);
}

.form-notice--error {
    color: var(--error);
    background: #faeeee;
    border-color: var(--error);
}

.rfq-form {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
}

.form-field--wide {
    grid-column: 1 / -1;
}

.form-field label {
    display: block;
    margin-bottom: 7px;
    color: var(--ink-soft);
    font-size: 13px;
    font-weight: 700;
}

.form-field label span {
    color: var(--blue);
    font-size: 10px;
    text-transform: uppercase;
}

.form-field input,
.form-field select,
.form-field textarea {
    width: 100%;
    color: var(--ink);
    background: var(--paper);
    border: 1px solid transparent;
    border-radius: 4px;
}

.form-field input,
.form-field select {
    height: 50px;
    padding: 0 13px;
}

.form-field textarea {
    min-height: 138px;
    padding: 12px 13px;
    resize: vertical;
}

.form-field input:focus,
.form-field select:focus,
.form-field textarea:focus {
    background: var(--white);
    border-color: var(--blue);
}

.form-submit {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    margin-top: 6px;
}

.form-submit small {
    max-width: 280px;
    color: var(--muted);
    font-size: 11px;
    text-align: right;
}

.honeypot {
    position: absolute;
    left: -10000px;
    width: 1px;
    height: 1px;
    overflow: hidden;
}

.site-footer {
    padding: 56px 0 26px;
    color: var(--white);
    background: #080b09;
}

.site-footer__top {
    display: grid;
    grid-template-columns: 0.65fr 1fr 0.85fr;
    gap: 60px;
    align-items: start;
}

.footer-brand small {
    margin-top: 3px;
    color: #9aa49d;
    font-size: 10px;
}

.footer-company {
    max-width: 500px;
}

.footer-company > strong,
.footer-company > span {
    display: block;
}

.footer-company > strong {
    color: var(--white);
    font-size: 14px;
}

.footer-company > span {
    margin-top: 4px;
    color: #9aa49d;
    font-size: 12px;
}

.footer-company > p {
    margin: 0;
    margin-top: 14px;
    color: #b8c1bb;
}

.footer-company dl {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
    margin: 20px 0 0;
}

.footer-company dt {
    color: #818a84;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
}

.footer-company dd {
    margin: 4px 0 0;
    color: #d7ddd9;
    font-size: 12px;
}

.site-footer nav {
    display: flex;
    flex-wrap: wrap;
    gap: 12px 22px;
    justify-content: flex-end;
}

.site-footer nav a {
    color: #d7ddd9;
    font-size: 13px;
    text-decoration: none;
}

.site-footer nav a:hover {
    color: var(--signal);
}

.site-footer__bottom {
    display: flex;
    justify-content: space-between;
    gap: 30px;
    padding-top: 28px;
    margin-top: 42px;
    color: #818a84;
    border-top: 1px solid #2d342f;
    font-size: 11px;
}

.site-footer__bottom p {
    max-width: 760px;
    margin: 0;
    text-align: right;
}

.product-detail__hero {
    padding: 42px 0 94px;
    background: var(--paper);
}

.detail-back {
    display: inline-flex;
    gap: 10px;
    align-items: center;
    margin-bottom: 34px;
    color: var(--ink-soft);
    font-size: 13px;
    font-weight: 700;
    text-decoration: none;
}

.detail-back:hover {
    color: var(--blue);
}

.product-detail__layout {
    display: grid;
    grid-template-columns: minmax(420px, 0.9fr) minmax(0, 1fr);
    gap: 80px;
    align-items: center;
}

.product-detail__image {
    position: relative;
    min-height: 620px;
    padding: 52px 38px 30px;
    background: var(--white);
    border-top: 4px solid var(--ink);
}

.product-detail__image > span {
    position: absolute;
    top: 18px;
    left: 20px;
    color: var(--muted);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
    font-size: 11px;
    font-weight: 700;
}

.product-detail__image img {
    width: 100%;
    height: 530px;
    object-fit: contain;
    mix-blend-mode: multiply;
}

.product-detail__copy h1 {
    font-size: 58px;
}

.site-language-zh .product-detail__copy h1 {
    font-size: 54px;
}

.product-detail__summary {
    max-width: 650px;
    margin: 24px 0 0;
    color: var(--ink-soft);
    font-size: 18px;
}

.product-specs {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    margin: 36px 0 30px;
    border-top: 1px solid var(--line);
}

.product-specs div {
    padding: 16px 14px 16px 0;
    border-bottom: 1px solid var(--line);
}

.product-specs dt {
    color: var(--muted);
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
}

.product-specs dd {
    margin: 6px 0 0;
    font-weight: 700;
}

.product-detail__copy .trademark-note {
    margin-top: 24px;
}

.detail-scope {
    background: var(--white);
}

.detail-scope__layout {
    display: grid;
    grid-template-columns: 0.75fr 1fr;
    gap: 80px;
}

.detail-scope ol {
    padding: 0;
    margin: 0;
    list-style: none;
    border-top: 1px solid var(--ink);
}

.detail-scope li {
    display: grid;
    grid-template-columns: 50px 1fr;
    gap: 14px;
    padding: 18px 0;
    border-bottom: 1px solid var(--line);
    font-weight: 600;
}

.detail-scope li span {
    color: var(--blue);
    font-family: "Bahnschrift", "Arial Narrow", sans-serif;
}

.related-products {
    background: var(--paper);
}

.related-products__heading {
    display: flex;
    justify-content: space-between;
    gap: 30px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--line);
}

.related-products__heading span {
    color: var(--muted);
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
}

.related-products__grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 22px;
    margin-top: 30px;
}

.related-products__grid a {
    display: grid;
    grid-template-columns: 120px 1fr;
    gap: 8px 18px;
    align-items: center;
    min-width: 0;
    padding: 14px;
    background: var(--white);
    text-decoration: none;
}

.related-products__grid img {
    grid-row: 1 / 3;
    width: 120px;
    height: 120px;
    object-fit: contain;
    mix-blend-mode: multiply;
}

.related-products__grid span {
    align-self: end;
    color: var(--blue);
    font-size: 11px;
    font-weight: 700;
}

.related-products__grid strong {
    align-self: start;
}

@media (max-width: 1120px) {
    .site-header__inner {
        grid-template-columns: minmax(190px, 1fr) auto auto;
        gap: 18px;
    }

    .site-nav {
        gap: 16px;
    }

    .header-cta {
        display: none;
    }

    .hero-layout {
        grid-template-columns: minmax(0, 1fr) minmax(380px, 0.78fr);
        gap: 46px;
    }

    h1 {
        font-size: 60px;
    }

    .site-language-zh h1 {
        font-size: 56px;
    }

    .catalog-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .proof-item {
        grid-template-columns: 1fr;
        gap: 7px;
    }

    .oem-layout {
        grid-template-columns: 0.72fr 1.28fr;
        gap: 48px;
    }

    .oem-steps,
    .quality-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .oem-steps li:nth-child(2),
    .quality-grid article:nth-child(2) {
        border-right: 0;
    }

    .oem-steps li:nth-child(-n+2),
    .quality-grid article:nth-child(-n+2) {
        border-bottom: 1px solid #42605a;
    }

    .product-detail__layout {
        gap: 48px;
    }

    .related-products__grid a {
        grid-template-columns: 90px 1fr;
    }

    .related-products__grid img {
        width: 90px;
        height: 90px;
    }
}

@media (max-width: 820px) {
    .site-shell,
    .site-header__inner {
        width: min(100% - 36px, 1280px);
    }

    .site-header__inner {
        grid-template-columns: 1fr auto auto;
        min-height: 68px;
    }

    .nav-toggle {
        display: block;
        grid-column: 2;
    }

    .site-nav {
        position: absolute;
        top: 68px;
        right: 0;
        left: 0;
        display: none;
        align-items: stretch;
        flex-direction: column;
        gap: 0;
        padding: 12px 18px 18px;
        background: var(--white);
        border-bottom: 1px solid var(--line);
    }

    .site-nav.is-open {
        display: flex;
    }

    .site-nav a {
        min-height: 46px;
        padding: 12px 0;
        border-bottom: 1px solid var(--line);
    }

    .site-nav a:last-child {
        border-bottom: 0;
    }

    .site-header__actions {
        grid-column: 3;
    }

    .hero-section {
        padding: 58px 0 68px;
    }

    .hero-section::after {
        font-size: 42px;
    }

    .hero-layout,
    .section-intro,
    .catalog-toolbar,
    .oem-layout,
    .rfq-layout,
    .product-detail__layout,
    .detail-scope__layout {
        grid-template-columns: 1fr;
    }

    .hero-layout {
        gap: 50px;
    }

    .hero-copy {
        max-width: none;
    }

    .hero-product__frame {
        min-height: 530px;
    }

    .section-intro {
        gap: 24px;
    }

    .catalog-toolbar {
        gap: 18px;
    }

    .catalog-filters {
        justify-content: flex-start;
    }

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

    .oem-layout {
        gap: 42px;
    }

    .oem-visual {
        grid-row: auto;
    }

    .rfq-intro {
        position: static;
    }

    .rfq-index {
        display: none;
    }

    .product-detail__image {
        min-height: 520px;
    }

    .product-detail__image img {
        height: 430px;
    }

    .related-products__grid {
        grid-template-columns: 1fr;
    }

    .site-footer__top {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .site-footer nav {
        justify-content: flex-start;
    }
}

@media (max-width: 620px) {
    .site-shell,
    .site-header__inner {
        width: min(100% - 28px, 1280px);
    }

    .site-brand__copy small {
        display: none;
    }

    .site-brand__mark {
        width: 38px;
        height: 38px;
    }

    .footer-company dl {
        grid-template-columns: 1fr;
    }

    .site-header__inner {
        grid-template-columns: 1fr 44px;
        gap: 8px;
        padding: 10px 0;
    }

    .nav-toggle {
        grid-column: 2;
    }

    .site-header__actions {
        grid-column: 1 / -1;
        grid-row: 2;
        justify-content: flex-start;
    }

    .site-nav {
        top: 116px;
    }

    .language-switcher {
        width: 100%;
    }

    .language-switcher a {
        flex: 1;
    }

    h1,
    .site-language-zh h1 {
        font-size: 44px;
        line-height: 1.08;
    }

    h2 {
        font-size: 34px;
    }

    .hero-lead,
    .section-intro p:last-child,
    .oem-copy p:last-child,
    .rfq-intro > p:last-of-type {
        font-size: 16px;
    }

    .hero-actions {
        align-items: stretch;
        flex-direction: column;
        gap: 8px;
    }

    .hero-actions .button {
        width: 100%;
    }

    .hero-product__frame {
        min-height: 450px;
        padding: 42px 14px 126px;
    }

    .hero-product__frame img {
        height: 310px;
    }

    .hero-product__caption {
        grid-template-columns: 1fr;
        gap: 3px;
        padding: 18px;
    }

    .hero-product__caption small {
        grid-row: auto;
    }

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

    .proof-item {
        min-height: 96px;
        padding: 16px;
        border-bottom: 1px solid #364039;
    }

    .proof-item:nth-child(odd) {
        border-left: 0;
    }

    .proof-item:last-child {
        border-right: 0;
    }

    .proof-item strong {
        font-size: 28px;
    }

    .catalog-section,
    .quality-section,
    .rfq-section,
    .related-products,
    .detail-scope,
    .oem-section {
        padding: 72px 0;
    }

    .catalog-filters {
        flex-wrap: nowrap;
        overflow-x: auto;
        padding-bottom: 4px;
        scrollbar-width: thin;
    }

    .catalog-filters button {
        flex: 0 0 auto;
    }

    .catalog-grid {
        grid-template-columns: 1fr;
        gap: 36px;
    }

    .catalog-card h3,
    .catalog-card__body > p {
        min-height: 0;
    }

    .oem-visual {
        grid-template-columns: 1fr 1fr;
    }

    .oem-visual figure:last-child {
        display: none;
    }

    .oem-steps,
    .quality-grid {
        grid-template-columns: 1fr;
    }

    .oem-steps li,
    .quality-grid article {
        min-height: 0;
        border-right: 0;
        border-bottom: 1px solid #42605a;
    }

    .quality-grid article {
        padding: 24px 0;
    }

    .quality-grid h3 {
        margin-top: 22px;
    }

    .rfq-form-wrap {
        padding: 24px 18px;
    }

    .rfq-form {
        grid-template-columns: 1fr;
    }

    .form-field--wide {
        grid-column: auto;
    }

    .form-submit {
        align-items: stretch;
        flex-direction: column;
    }

    .form-submit .button {
        width: 100%;
    }

    .form-submit small {
        max-width: none;
        text-align: left;
    }

    .product-detail__hero {
        padding: 28px 0 70px;
    }

    .product-detail__image {
        min-height: 420px;
        padding: 42px 14px 16px;
    }

    .product-detail__image img {
        height: 360px;
    }

    .product-detail__copy h1,
    .site-language-zh .product-detail__copy h1 {
        font-size: 42px;
    }

    .product-specs {
        grid-template-columns: 1fr;
    }

    .detail-scope__layout {
        gap: 36px;
    }

    .related-products__heading,
    .site-footer__bottom {
        align-items: flex-start;
        flex-direction: column;
    }

    .site-footer__bottom p {
        text-align: left;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        transition-duration: 0.01ms !important;
    }
}