/* ============================================================
   ARCBEND - Tube Bending Machine Manufacturer (model-02)
   DNA: monochrome photography that colors on hover
        + near-white paper / graphite bands + cobalt blue
        + skewed parallelogram buttons & tags (bend motif)
        + translateX slide-in reveals / HarmonyOS Sans
   ============================================================ */

:root{
    --c-bg:#FAFBFC;
    --c-tint:#F0F2F5;
    --c-white:#FFFFFF;
    --c-ink:#17191D;
    --c-ink-2:#101216;
    --c-text:#4C545E;
    --c-mute:#8A929C;
    --c-blue:#1F5EDC;
    --c-blue-deep:#1749AC;
    --c-line:#E1E5EA;
    --c-line-dark:#2C3038;
    --shell:min(144rem,calc(100% - 8rem));
    --skew:-8deg;
    --font:'HarmonyOS Sans',system-ui,-apple-system,'Segoe UI',sans-serif;
}

*{margin:0;padding:0;box-sizing:border-box;}
html{font-size:clamp(9px,0.6945vw,11px);scroll-behavior:smooth;scroll-padding-top:9rem;}
body{font-family:var(--font);font-size:1.6rem;line-height:1.6;background:var(--c-bg);color:var(--c-ink);-webkit-font-smoothing:antialiased;}
img{display:block;max-width:100%;}
a{text-decoration:none;color:inherit;}
ul,ol{list-style:none;}
button{font-family:inherit;background:none;border:none;cursor:pointer;}

.index_shell{width:var(--shell);margin:0 auto;}

/* photos ship monochrome, color returns on hover */
.index_app img,.index_case img,.index_pane-media img,.index_factory-photo img,.index_duo-media img{
    filter:grayscale(1) contrast(1.04);
    transition:filter .5s ease,transform .5s ease;
}
.index_app:hover img,.index_case:hover img,.index_pane:hover .index_pane-media img,
.index_factory-photo:hover img,.index_duo-media:hover img{filter:grayscale(0) contrast(1);}

/* ---------- buttons: parallelogram ---------- */
.index_btn{display:inline-block;padding:1.5rem 3.2rem;transform:skewX(var(--skew));font-size:1.5rem;font-weight:700;transition:background .25s,color .25s,border-color .25s;}
.index_btn>span{display:inline-block;transform:skewX(calc(var(--skew) * -1));}
.index_btn-solid{background:var(--c-blue);color:#fff;}
.index_btn-solid:hover{background:var(--c-blue-deep);}
.index_btn-ghost{border:1px solid rgba(255,255,255,.65);color:#fff;}
.index_btn-ghost:hover{background:rgba(255,255,255,.14);border-color:#fff;}
.index_btn-line{border:1px solid var(--c-ink);color:var(--c-ink);padding:1.2rem 2.6rem;}
.index_btn-line:hover{background:var(--c-ink);color:#fff;}

/* ---------- header ---------- */
.index_bar{position:sticky;top:0;z-index:120;background:rgba(250,251,252,.92);backdrop-filter:blur(10px);border-bottom:1px solid var(--c-line);}
.index_bar-in{height:8.4rem;display:flex;align-items:center;gap:4rem;}
.index_brand{display:flex;align-items:center;gap:1.2rem;}
.index_brand-mark{display:grid;place-items:center;width:3.6rem;height:3.6rem;background:var(--c-ink);color:#fff;font-size:1.4rem;font-weight:900;letter-spacing:.02em;transform:skewX(var(--skew));}
.index_brand-name{font-size:1.9rem;font-weight:900;letter-spacing:.14em;}
.index_nav{display:flex;gap:.4rem;margin-left:auto;}
.index_nav a{padding:1rem 1.5rem;font-size:1.45rem;font-weight:500;color:var(--c-text);transition:color .2s;}
.index_nav a:hover{color:var(--c-ink);}
.index_bar-cta{flex-shrink:0;}
.index_burger{display:none;font-size:2.6rem;color:var(--c-ink);}
.index_drawer{display:none;}

/* ---------- hero ---------- */
.index_hero{position:relative;isolation:isolate;}
.index_hero-bg{position:absolute;inset:0;z-index:-1;width:100%;height:100%;object-fit:cover;filter:grayscale(1) contrast(1.05);}
.index_hero::before{content:'';position:absolute;inset:0;z-index:0;background:linear-gradient(100deg,rgba(12,14,18,.82) 0%,rgba(12,14,18,.55) 52%,rgba(12,14,18,.18) 100%);}
.index_hero-in{position:relative;z-index:1;padding:15rem 0 12rem;}
.index_hero-copy{max-width:66rem;color:#fff;}
.index_hero-copy h1{font-size:5.4rem;line-height:1.1;font-weight:900;letter-spacing:-.01em;}
.index_hero-copy p{margin-top:2.4rem;font-size:1.7rem;line-height:1.7;color:rgba(255,255,255,.85);max-width:56rem;}
.index_hero-actions{margin-top:3.6rem;display:flex;gap:1.6rem;flex-wrap:wrap;}
.index_hero-strip{position:relative;z-index:1;background:var(--c-ink);}
.index_strip-in{display:grid;grid-template-columns:repeat(4,1fr);}
.index_strip-item{padding:2.8rem 3rem 2.8rem 0;border-left:1px solid var(--c-line-dark);padding-left:3rem;color:#fff;}
.index_strip-item:first-child{border-left:0;padding-left:0;}
.index_strip-item strong{display:block;font-size:2.6rem;font-weight:900;color:#fff;}
.index_strip-item span{display:block;margin-top:.4rem;font-size:1.35rem;color:#9AA3AE;}

/* ---------- sections ---------- */
.index_sec{padding:10rem 0;}
.index_sec-tint{background:var(--c-tint);}
.index_head{max-width:76rem;margin-bottom:5.6rem;}
.index_head h2{font-size:3.6rem;line-height:1.15;font-weight:900;letter-spacing:-.01em;}
.index_head p{margin-top:1.6rem;font-size:1.6rem;color:var(--c-text);}

/* ---------- machines: vertical tabs ---------- */
.index_tabs{display:grid;grid-template-columns:34rem 1fr;gap:4rem;align-items:start;}
.index_tabs-rail{display:flex;flex-direction:column;gap:1rem;}
.index_tab{text-align:left;padding:2.2rem 2.4rem;background:var(--c-white);border:1px solid var(--c-line);border-left:3px solid transparent;transition:border-color .25s,background .25s;}
.index_tab strong{display:block;font-size:1.7rem;font-weight:700;}
.index_tab span{display:block;margin-top:.5rem;font-size:1.35rem;color:var(--c-mute);}
.index_tab:hover{border-left-color:var(--c-mute);}
.index_tab.is-on{border-left-color:var(--c-blue);background:var(--c-ink);}
.index_tab.is-on strong{color:#fff;}
.index_tab.is-on span{color:#9AA3AE;}
.index_tabs-stage{position:relative;background:var(--c-white);border:1px solid var(--c-line);}
.index_pane{display:none;grid-template-columns:1.15fr 1fr;}
.index_pane.is-on{display:grid;animation:panein .45s ease both;}
@keyframes panein{from{opacity:0;transform:translateX(2.4rem);}to{opacity:1;transform:none;}}
.index_pane-media{overflow:hidden;}
.index_pane-media img{width:100%;height:100%;object-fit:cover;aspect-ratio:4/3;}
.index_pane-body{padding:4rem 4.4rem;display:flex;flex-direction:column;align-items:flex-start;}
.index_pane-body h3{font-size:2.4rem;font-weight:900;}
.index_pane-body>p{margin-top:1.4rem;font-size:1.5rem;color:var(--c-text);}
.index_pane-specs{margin:2.4rem 0 3rem;width:100%;display:grid;grid-template-columns:1fr 1fr;gap:1rem 2rem;}
.index_pane-specs li{position:relative;padding-left:1.8rem;font-size:1.42rem;font-weight:500;}
.index_pane-specs li::before{content:'';position:absolute;left:0;top:.75em;width:.9rem;height:.22rem;background:var(--c-blue);transform:skewX(var(--skew));}
.index_pane-body .index_btn{margin-top:auto;}

/* ---------- precision duo ---------- */
.index_duo{display:grid;grid-template-columns:1fr 1.05fr;gap:6rem;align-items:center;padding-top:10rem;padding-bottom:10rem;}
.index_sec-tint .index_duo{padding-top:0;padding-bottom:0;}
#precision{padding:10rem 0;}
.index_duo-media{overflow:hidden;}
.index_duo-media img{width:100%;aspect-ratio:4/3;object-fit:cover;}
.index_duo-body h2{font-size:3.6rem;line-height:1.15;font-weight:900;letter-spacing:-.01em;}
.index_duo-body>p{margin-top:1.6rem;font-size:1.6rem;color:var(--c-text);}
.index_checks{margin-top:3.4rem;display:grid;gap:2.2rem;}
.index_checks li{display:flex;gap:1.6rem;align-items:flex-start;}
.index_checks i{font-size:2.2rem;color:var(--c-blue);flex-shrink:0;margin-top:.2rem;}
.index_checks strong{display:block;font-size:1.6rem;font-weight:700;}
.index_checks span{display:block;margin-top:.3rem;font-size:1.42rem;color:var(--c-text);}

/* ---------- applications ---------- */
.index_apps{display:grid;grid-template-columns:repeat(4,1fr);gap:2.4rem;}
.index_app{position:relative;overflow:hidden;isolation:isolate;}
.index_app img{width:100%;aspect-ratio:3/4;object-fit:cover;}
.index_app:hover img{transform:scale(1.04);}
.index_app-cap{position:absolute;inset:auto 0 0 0;z-index:1;padding:14rem 2.4rem 2.4rem;background:linear-gradient(to top,rgba(12,14,18,.88) 0%,rgba(12,14,18,.42) 62%,transparent 100%);color:#fff;}
.index_app-cap h3{font-size:1.9rem;font-weight:700;}
.index_app-cap p{margin-top:.7rem;font-size:1.35rem;line-height:1.55;color:rgba(255,255,255,.82);}

/* ---------- factory (graphite band) ---------- */
.index_factory{background:var(--c-ink);color:#fff;padding:10rem 0;}
.index_factory-grid{display:grid;grid-template-columns:1fr 1.1fr;gap:6rem;align-items:center;}
.index_factory-copy h2{font-size:3.6rem;line-height:1.15;font-weight:900;letter-spacing:-.01em;}
.index_factory-copy>p{margin-top:1.8rem;font-size:1.55rem;line-height:1.7;color:#B7BEC7;}
.index_factory-facts{margin:3.6rem 0 4rem;display:grid;grid-template-columns:1fr 1fr;gap:2.6rem 3rem;}
.index_factory-facts strong{display:block;font-size:2.4rem;font-weight:900;color:var(--c-white);}
.index_factory-facts span{display:block;margin-top:.3rem;font-size:1.35rem;color:#9AA3AE;}
.index_factory-media{display:grid;gap:2.4rem;}
.index_factory-photo{overflow:hidden;}
.index_factory-photo img{width:100%;object-fit:cover;}
.index_factory-photo:first-child img{aspect-ratio:16/9;}
.index_factory-photo:last-child img{aspect-ratio:16/7;object-position:center 30%;}

/* ---------- process steps ---------- */
.index_steps{display:grid;grid-template-columns:repeat(5,1fr);gap:2.4rem;counter-reset:step;}
.index_step{background:var(--c-white);border:1px solid var(--c-line);border-top:3px solid var(--c-ink);padding:2.6rem 2.4rem 3rem;transition:border-color .25s,transform .25s;}
.index_step:hover{border-top-color:var(--c-blue);transform:translateY(-.4rem);}
.index_step-no{display:inline-grid;place-items:center;min-width:3.4rem;height:3.4rem;background:var(--c-ink);color:#fff;font-size:1.5rem;font-weight:900;transform:skewX(var(--skew));}
.index_step h3{margin-top:1.8rem;font-size:1.8rem;font-weight:700;}
.index_step p{margin-top:.8rem;font-size:1.38rem;color:var(--c-text);}

/* ---------- cases ---------- */
.index_cases{display:grid;grid-template-columns:repeat(3,1fr);gap:2.4rem;}
.index_case{background:var(--c-white);border:1px solid var(--c-line);display:flex;flex-direction:column;transition:transform .25s,box-shadow .25s;}
.index_case:hover{transform:translateY(-.4rem);box-shadow:0 1.6rem 3.6rem rgba(23,25,29,.1);}
.index_case figure{overflow:hidden;}
.index_case img{width:100%;aspect-ratio:4/3;object-fit:cover;}
.index_case-body{padding:2.6rem 2.8rem 3.2rem;}
.index_case-tag{display:inline-block;padding:.5rem 1.4rem;background:var(--c-tint);font-size:1.2rem;font-weight:700;letter-spacing:.04em;color:var(--c-text);transform:skewX(var(--skew));}
.index_case-body h3{margin-top:1.6rem;font-size:2rem;font-weight:700;}
.index_case-body p{margin-top:.9rem;font-size:1.42rem;color:var(--c-text);}

/* ---------- FAQ ---------- */
.index_faq-grid{display:grid;grid-template-columns:38rem 1fr;gap:6rem;align-items:start;}
.index_faq-head{position:sticky;top:11rem;margin-bottom:0;}
.index_faq-list{display:grid;gap:1.2rem;}
.index_faq-item{background:var(--c-white);border:1px solid var(--c-line);}
.index_faq-item summary{display:flex;justify-content:space-between;align-items:center;gap:2rem;padding:2.2rem 2.8rem;font-size:1.65rem;font-weight:700;cursor:pointer;list-style:none;}
.index_faq-item summary::-webkit-details-marker{display:none;}
.index_faq-item summary i{font-size:1.9rem;color:var(--c-blue);transition:transform .25s;flex-shrink:0;}
.index_faq-item[open] summary i{transform:rotate(45deg);}
.index_faq-item p{padding:0 2.8rem 2.4rem;font-size:1.45rem;color:var(--c-text);}

/* ---------- contact ---------- */
.index_contact{position:relative;isolation:isolate;padding:10rem 0;color:#fff;}
.index_contact-bg{position:absolute;inset:0;z-index:-1;width:100%;height:100%;object-fit:cover;}
.index_contact::before{content:'';position:absolute;inset:0;z-index:-1;background:rgba(12,14,18,.55);}
.index_contact-grid{display:grid;grid-template-columns:1fr 1.05fr;gap:6rem;align-items:center;}
.index_contact-copy h2{font-size:3.6rem;line-height:1.15;font-weight:900;letter-spacing:-.01em;}
.index_contact-copy>p{margin-top:1.6rem;font-size:1.6rem;color:rgba(255,255,255,.85);max-width:46rem;}
.index_contact-list{margin-top:3.4rem;display:grid;gap:1.6rem;}
.index_contact-list li{display:flex;align-items:center;gap:1.4rem;font-size:1.55rem;}
.index_contact-list i{font-size:2rem;color:#7FA6F2;}
.index_form{background:var(--c-white);color:var(--c-ink);padding:4rem 4.4rem;}
.index_form-row{display:grid;grid-template-columns:1fr 1fr;gap:1.8rem;}
.index_form label{display:block;margin-bottom:1.8rem;font-size:1.35rem;font-weight:700;}
.index_form input,.index_form textarea{display:block;width:100%;margin-top:.7rem;padding:1.3rem 1.5rem;border:1px solid #C9CFD6;background:var(--c-bg);font-family:inherit;font-size:1.45rem;color:var(--c-ink);transition:border-color .2s;resize:vertical;}
.index_form input:focus,.index_form textarea:focus{outline:none;border-color:var(--c-blue);}
.index_form .index_btn{width:100%;text-align:center;}
.index_form-note{margin-top:1.6rem;font-size:1.3rem;color:var(--c-mute);text-align:center;}

/* ---------- footer ---------- */
.index_footer{background:var(--c-bg);border-top:3px solid var(--c-ink);}
.index_footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr 1.1fr;gap:4rem;padding:7rem 0 5rem;}
.index_footer-brand p{margin-top:2rem;font-size:1.4rem;color:var(--c-text);max-width:34rem;}
.index_footer-social{margin-top:2.4rem;display:flex;gap:1rem;}
.index_footer-social a{display:grid;place-items:center;width:3.8rem;height:3.8rem;border:1px solid var(--c-line);font-size:1.8rem;color:var(--c-text);transition:all .2s;transform:skewX(var(--skew));}
.index_footer-social a i{transform:skewX(calc(var(--skew) * -1));}
.index_footer-social a:hover{background:var(--c-ink);border-color:var(--c-ink);color:#fff;}
.index_footer-col h4{font-size:1.5rem;font-weight:900;letter-spacing:.06em;margin-bottom:2rem;}
.index_footer-col a,.index_footer-col span{display:block;margin-bottom:1.2rem;font-size:1.42rem;color:var(--c-text);transition:color .2s;}
.index_footer-col a:hover{color:var(--c-blue);}
.index_footer-base{display:flex;justify-content:space-between;gap:2rem;padding:2.6rem 0;border-top:1px solid var(--c-line);font-size:1.3rem;color:var(--c-mute);}

/* ---------- slide-in reveals ---------- */
.index_slide{opacity:0;transform:translateX(-3.2rem);transition:opacity .7s ease,transform .7s ease;}
.index_slide.is-in{opacity:1;transform:none;}

/* ---------- responsive ---------- */
@media (max-width:1024px){
    .index_nav,.index_bar-cta{display:none;}
    .index_burger{display:block;margin-left:auto;}
    .index_drawer.is-open{display:flex;flex-direction:column;gap:.4rem;padding:2rem 4rem 3rem;background:var(--c-bg);border-bottom:1px solid var(--c-line);}
    .index_drawer a{padding:1.2rem 0;font-size:1.7rem;font-weight:500;}
    .index_drawer .index_btn{margin-top:1.2rem;text-align:center;}
    .index_strip-in{grid-template-columns:1fr 1fr;}
    .index_strip-item{border-left:0;padding-left:0;}
    .index_tabs{grid-template-columns:1fr;}
    .index_tabs-rail{flex-direction:row;overflow-x:auto;}
    .index_tab{flex:1 0 24rem;border-left:0;border-top:3px solid transparent;}
    .index_tab.is-on{border-top-color:var(--c-blue);}
    .index_pane{grid-template-columns:1fr;}
    .index_duo,.index_factory-grid,.index_contact-grid{grid-template-columns:1fr;gap:4rem;}
    .index_apps{grid-template-columns:1fr 1fr;}
    .index_steps{grid-template-columns:repeat(2,1fr);}
    .index_cases{grid-template-columns:1fr;}
    .index_faq-grid{grid-template-columns:1fr;gap:3rem;}
    .index_faq-head{position:static;}
    .index_footer-grid{grid-template-columns:1fr 1fr;}
}
@media (max-width:640px){
    html{font-size:9px;}
    .index_shell{width:calc(100% - 4rem);}
    .index_hero-copy h1{font-size:4.2rem;}
    .index_hero-in{padding:10rem 0 8rem;}
    .index_sec,.index_factory,.index_contact{padding:7rem 0;}
    .index_strip-in{grid-template-columns:1fr;}
    .index_strip-item{padding:1.6rem 0;}
    .index_apps,.index_steps,.index_form-row{grid-template-columns:1fr;}
    .index_pane-body{padding:3rem 2.4rem;}
    .index_form{padding:3rem 2.4rem;}
    .index_footer-grid{grid-template-columns:1fr;}
    .index_footer-base{flex-direction:column;gap:.6rem;}
}

@media (prefers-reduced-motion:reduce){
    html{scroll-behavior:auto;}
    .index_slide{opacity:1;transform:none;transition:none;}
    .index_pane.is-on{animation:none;}
    .index_app img,.index_case img,.index_pane-media img,.index_factory-photo img,.index_duo-media img{transition:none;}
}