/* THHANWEI — aluminium supply & processing
   Design system v1.0 — industrial blue-grey */

:root{
  --ink:#0B1A26;
  --navy:#0F2536;
  --navy-2:#16364C;
  --steel:#5C7488;
  --slate:#8497A6;
  --mist:#E3E9EE;
  --line:#D5DDE4;
  --paper:#F4F6F8;
  --white:#fff;
  --accent:#FF5A1F;
  --accent-dk:#D9450F;
  --wrap:1280px;
  --gut:clamp(20px,4vw,56px);
  --sp-section:clamp(64px,7.5vw,124px);
  --font:"Inter","Helvetica Neue",Arial,"PingFang SC","Microsoft YaHei",sans-serif;
  --display:"Barlow Condensed","Inter",Impact,sans-serif;
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;background:var(--white);color:var(--ink);
  font-family:var(--font);font-size:16px;line-height:1.65;
  -webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
button{font:inherit}
h1,h2,h3,h4{font-family:var(--display);font-weight:600;line-height:.98;letter-spacing:.005em;margin:0;text-transform:uppercase}
p{margin:0}
ul{margin:0;padding:0;list-style:none}

.wrap{width:100%;max-width:var(--wrap);margin:0 auto;padding:0 var(--gut)}
.section{padding:var(--sp-section) 0}
.section--paper{background:var(--paper)}
.section--ink{background:var(--navy);color:#fff}
.section--tight{padding:clamp(44px,5vw,72px) 0}

.eyebrow{
  display:flex;align-items:center;gap:14px;
  font-size:11px;font-weight:600;letter-spacing:.22em;text-transform:uppercase;
  color:var(--accent);margin-bottom:22px;
}
.eyebrow::before{content:"";width:26px;height:1px;background:var(--accent);flex:none}
.eyebrow--muted{color:var(--slate)}
.eyebrow--muted::before{background:var(--slate)}

.h-xl{font-size:clamp(2.5rem,5.6vw,4.75rem)}
.h-lg{font-size:clamp(2rem,3.6vw,3.25rem)}
.h-md{font-size:clamp(1.45rem,2.2vw,2rem)}
.h-sm{font-size:clamp(1.1rem,1.4vw,1.3rem)}
.lede{font-size:clamp(1rem,1.15vw,1.125rem);line-height:1.7;color:var(--steel);max-width:56ch}
.section--ink .lede{color:#A9BCCB}
.muted{color:var(--steel)}

.section-head{display:flex;gap:clamp(24px,5vw,80px);align-items:flex-end;justify-content:space-between;flex-wrap:wrap;margin-bottom:clamp(36px,4vw,60px)}
.section-head__copy{max-width:640px}
.section-head .link-arrow{margin-bottom:6px}

.link-arrow{
  display:inline-flex;align-items:center;gap:10px;
  font-size:12px;font-weight:600;letter-spacing:.14em;text-transform:uppercase;
  color:var(--ink);border-bottom:1px solid var(--line);padding-bottom:6px;
  transition:color .2s,border-color .2s;
}
.link-arrow svg{width:14px;height:14px;transition:transform .25s}
.link-arrow:hover{color:var(--accent);border-color:var(--accent)}
.link-arrow:hover svg{transform:translateX(4px)}
.section--ink .link-arrow{color:#fff;border-color:rgba(255,255,255,.25)}
.section--ink .link-arrow:hover{color:var(--accent);border-color:var(--accent)}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:10px;
  padding:15px 26px;font-size:12px;font-weight:600;letter-spacing:.12em;
  text-transform:uppercase;border:1px solid transparent;border-radius:2px;
  cursor:pointer;transition:background .2s,color .2s,border-color .2s,transform .2s;
  white-space:nowrap;
}
.btn svg{width:13px;height:13px}
.btn--primary{background:var(--accent);color:#fff}
.btn--primary:hover{background:var(--accent-dk)}
.btn--ink{background:var(--navy);color:#fff}
.btn--ink:hover{background:var(--navy-2)}
.btn--ghost{border-color:var(--line);color:var(--ink);background:transparent}
.btn--ghost:hover{border-color:var(--ink)}
.btn--line{border-color:rgba(255,255,255,.4);color:#fff}
.btn--line:hover{border-color:#fff;background:rgba(255,255,255,.08)}

/* ---------- header ---------- */
.site-head{position:sticky;top:0;z-index:60;background:rgba(255,255,255,.96);border-bottom:1px solid var(--line);backdrop-filter:blur(10px)}
.site-head__inner{display:flex;align-items:center;justify-content:space-between;gap:24px;height:76px}
.brand{display:flex;align-items:center;gap:12px;flex:none}
.brand__mark{width:32px;height:32px;flex:none}
.brand__name{font-family:var(--display);font-size:1.5rem;font-weight:700;letter-spacing:.04em;line-height:1;text-transform:uppercase}
.brand__name span{color:var(--accent)}
.brand__tag{display:block;font-family:var(--font);font-size:9px;font-weight:500;letter-spacing:.2em;color:var(--slate);text-transform:uppercase;margin-top:3px}

.nav{display:flex;align-items:center;gap:clamp(18px,2.4vw,34px)}
.nav ul,.nav__list{display:flex;align-items:center;gap:clamp(18px,2.4vw,34px);margin:0;padding:0}
.nav li{display:flex}
.mnav{margin:0;padding:0}
.nav a{font-size:13px;font-weight:500;letter-spacing:.02em;color:var(--ink);position:relative;padding:6px 0}
.nav a::after{content:"";position:absolute;left:0;bottom:0;width:0;height:2px;background:var(--accent);transition:width .25s}
.nav a:hover::after,.nav a.is-active::after{width:100%}
.nav a.is-active{font-weight:600}
.head-actions{display:flex;align-items:center;gap:14px}
.head-actions .btn{padding:12px 20px}
.nav-toggle{display:none;width:44px;height:44px;align-items:center;justify-content:center;background:none;border:1px solid var(--line);border-radius:2px;cursor:pointer}
.nav-toggle span{display:block;width:18px;height:1.5px;background:var(--ink);position:relative}
.nav-toggle span::before,.nav-toggle span::after{content:"";position:absolute;left:0;width:18px;height:1.5px;background:var(--ink)}
.nav-toggle span::before{top:-6px}.nav-toggle span::after{top:6px}

.topline{background:var(--ink);color:#B9C8D4;font-size:11px;letter-spacing:.08em}
.topline .wrap{display:flex;justify-content:space-between;align-items:center;gap:20px;height:34px;text-transform:uppercase}
.topline a{color:#fff}
.topline strong{color:#fff;font-weight:600}

/* ---------- hero ---------- */
.hero{position:relative;background:var(--ink);color:#fff;overflow:hidden;isolation:isolate}
.hero__media{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:-2}
.hero::after{content:"";position:absolute;inset:0;z-index:-1;
  background:
    linear-gradient(180deg,rgba(8,21,32,0) 52%,rgba(8,21,32,.72) 88%,rgba(8,21,32,.9) 100%),
    linear-gradient(100deg,rgba(8,21,32,.96) 0%,rgba(8,21,32,.84) 42%,rgba(8,21,32,.38) 78%,rgba(8,21,32,.30) 100%)}
.hero__inner{padding:clamp(64px,9vw,132px) 0 clamp(40px,5vw,64px);max-width:760px}
.hero .eyebrow{color:#fff}
.hero .eyebrow::before{background:var(--accent)}
.hero h1{margin-bottom:26px}
.hero h1 em{font-style:normal;color:#C9D7E2;display:block}
.hero .lede{color:#BFD0DD;margin-bottom:38px;max-width:52ch}
.hero__cta{display:flex;flex-wrap:wrap;gap:14px}

.stat-strip{display:grid;grid-template-columns:repeat(4,1fr);border-top:1px solid rgba(255,255,255,.18);margin-top:clamp(40px,5vw,72px)}
.stat{padding:26px 24px 30px;border-right:1px solid rgba(255,255,255,.13)}
.stat:last-child{border-right:0}
.stat__num{font-family:var(--display);font-size:clamp(2rem,3vw,2.75rem);font-weight:600;line-height:1;color:#fff}
.stat__num sup{font-size:.5em;color:var(--accent);top:-.7em;margin-left:2px}
.stat__label{font-size:11px;letter-spacing:.16em;text-transform:uppercase;color:#96AEBF;margin-top:10px}

/* ---------- category cards ---------- */
.cat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--line);border:1px solid var(--line)}
.cat{background:#fff;display:flex;flex-direction:column;padding:0;position:relative;overflow:hidden}
.cat__figure{position:relative;aspect-ratio:4/3;overflow:hidden;background:var(--mist)}
.cat__figure img{width:100%;height:100%;object-fit:cover;transition:transform .6s cubic-bezier(.2,.7,.3,1)}
.cat:hover .cat__figure img{transform:scale(1.05)}
.cat__body{padding:22px 22px 26px;display:flex;flex-direction:column;gap:10px;flex:1}
.cat__title{font-family:var(--display);font-size:1.35rem;font-weight:600;text-transform:uppercase;letter-spacing:.01em;line-height:1.1}
.cat__meta{font-size:12px;color:var(--slate);letter-spacing:.02em}
.cat__spec{display:flex;flex-wrap:wrap;gap:6px;margin-top:auto;padding-top:14px}
.chip{font-size:10.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--steel);border:1px solid var(--line);padding:4px 8px;border-radius:2px}
.cat__go{position:absolute;top:16px;right:16px;width:34px;height:34px;display:grid;place-items:center;background:rgba(255,255,255,.92);border-radius:50%;opacity:0;transform:translateY(-4px);transition:.3s}
.cat:hover .cat__go{opacity:1;transform:none}
.cat__go svg{width:13px;height:13px}

/* ---------- split feature ---------- */
.split{display:grid;grid-template-columns:1.05fr .95fr;gap:clamp(32px,5vw,80px);align-items:center}
.split--rev .split__media{order:2}
.split__media{position:relative}
.split__media img{width:100%;aspect-ratio:4/3;object-fit:cover}
.split__media::before{content:"";position:absolute;inset:auto -18px -18px auto;width:42%;height:42%;border:1px solid rgba(255,90,31,.55);z-index:-1}
.split__body .h-lg{margin-bottom:22px}
.split__body p+p{margin-top:16px}

.feature-list{display:grid;gap:0;margin-top:34px;border-top:1px solid var(--line)}
.feature-list li{display:flex;gap:18px;padding:18px 0;border-bottom:1px solid var(--line);align-items:flex-start}
.feature-list .num{font-family:var(--display);font-size:.95rem;color:var(--accent);letter-spacing:.08em;padding-top:2px;flex:none;width:26px}
.feature-list h4{font-size:1.05rem;margin-bottom:4px;letter-spacing:.02em}
.feature-list p{font-size:14px;color:var(--steel);line-height:1.6}
.section--ink .feature-list,.section--ink .feature-list li{border-color:rgba(255,255,255,.16)}
.section--ink .feature-list p{color:#9FB4C4}

/* ---------- applications ---------- */
.apps{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:rgba(255,255,255,.14)}
.app{background:var(--navy);padding:28px 24px 30px;transition:background .25s}
.app:hover{background:var(--navy-2)}
.app__idx{font-size:11px;letter-spacing:.18em;color:var(--accent);margin-bottom:18px}
.app h4{font-size:1.15rem;margin-bottom:8px;line-height:1.15}
.app p{font-size:13px;color:#93A9BA;line-height:1.55}

/* ---------- process ---------- */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:clamp(20px,3vw,40px);counter-reset:s}
.step{position:relative;padding-top:26px;border-top:2px solid var(--line)}
.step::before{counter-increment:s;content:"0" counter(s);position:absolute;top:-14px;left:0;background:#fff;padding-right:12px;font-family:var(--display);font-size:13px;letter-spacing:.1em;color:var(--accent)}
.step h4{font-size:1.1rem;margin-bottom:8px}
.step p{font-size:13.5px;color:var(--steel);line-height:1.6}

/* ---------- spec table ---------- */
.spec-table{width:100%;border-collapse:collapse;font-size:14px}
.spec-table caption{text-align:left;font-family:var(--display);font-size:1.1rem;letter-spacing:.04em;text-transform:uppercase;padding-bottom:12px;color:var(--ink)}
.spec-table th,.spec-table td{text-align:left;padding:13px 16px;border-bottom:1px solid var(--line);vertical-align:top}
.spec-table th{width:34%;font-weight:600;color:var(--ink);background:var(--paper);font-size:12px;letter-spacing:.08em;text-transform:uppercase}
.spec-table td{color:var(--steel)}
.spec-table tr:first-child th,.spec-table tr:first-child td{border-top:1px solid var(--line)}

/* ---------- page hero (inner pages) ---------- */
.page-hero{background:var(--navy);color:#fff;position:relative;overflow:hidden}
.page-hero::before{content:"";position:absolute;inset:0;
  background-image:linear-gradient(rgba(255,255,255,.045) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px);
  background-size:64px 64px;mask-image:linear-gradient(90deg,transparent,#000 60%)}
.page-hero__inner{position:relative;padding:clamp(44px,6vw,78px) 0 clamp(40px,5vw,64px);max-width:820px}
.crumbs{display:flex;gap:10px;align-items:center;font-size:11px;letter-spacing:.12em;text-transform:uppercase;color:#8FA7B7;margin-bottom:26px}
.crumbs a:hover{color:#fff}
.crumbs .sep{color:#4C6A80}
.page-hero h1{font-size:clamp(2.2rem,4.4vw,3.6rem);margin-bottom:18px}
.page-hero .lede{color:#AEC2D1}

/* ---------- CTA band ---------- */
.cta-band{background:var(--accent);color:#fff;padding:clamp(40px,5vw,64px) 0}
.cta-band .wrap{display:flex;align-items:center;justify-content:space-between;gap:32px;flex-wrap:wrap}
.cta-band h2{font-size:clamp(1.6rem,2.8vw,2.4rem);max-width:22ch}
.cta-band p{font-size:14px;color:rgba(255,255,255,.85);margin-top:10px;max-width:46ch}
.cta-band .btn--ink:hover{background:#08131c}

/* ---------- footer ---------- */
.site-foot{background:var(--ink);color:#93A9BA;padding:clamp(52px,6vw,80px) 0 0;font-size:14px}
.site-foot a:hover{color:#fff}
.foot-grid{display:grid;grid-template-columns:1.4fr .8fr .8fr 1fr;gap:clamp(28px,4vw,56px);padding-bottom:clamp(36px,5vw,56px)}
.site-foot .brand__name{color:#fff;font-size:1.6rem}
.site-foot .brand{margin-bottom:18px}
.foot-about{max-width:34ch;line-height:1.7}
.foot-title{font-family:var(--display);font-size:.95rem;letter-spacing:.14em;text-transform:uppercase;color:#fff;margin-bottom:18px}
.foot-list{display:grid;gap:11px}
.foot-list a{color:#93A9BA}
.foot-contact{display:grid;gap:14px}
.foot-contact dt{font-size:10.5px;letter-spacing:.16em;text-transform:uppercase;color:#5D7688;margin-bottom:2px}
.foot-contact dd{margin:0;color:#D6E1E9}
.foot-bottom{border-top:1px solid rgba(255,255,255,.12);padding:22px 0 26px;display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;font-size:12px;color:#6C8398}

/* ---------- forms ---------- */
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.field{display:grid;gap:8px}
.field--full{grid-column:1/-1}
.field label{font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--steel);font-weight:600}
.field input,.field select,.field textarea{
  width:100%;padding:13px 14px;border:1px solid var(--line);border-radius:2px;background:#fff;
  font-family:inherit;font-size:14px;color:var(--ink);transition:border-color .2s
}
.field input:focus,.field select:focus,.field textarea:focus{outline:none;border-color:var(--navy)}
.field textarea{min-height:130px;resize:vertical}
.form-note{font-size:12px;color:var(--slate);margin-top:14px}

.contact-aside{background:var(--paper);border:1px solid var(--line);padding:clamp(24px,3vw,38px)}
.contact-aside h3{margin-bottom:20px}
.contact-list{display:grid;gap:20px}
.contact-list dt{font-size:10.5px;letter-spacing:.16em;text-transform:uppercase;color:var(--slate);margin-bottom:4px}
.contact-list dd{margin:0;font-size:15px;color:var(--ink);line-height:1.5}
.contact-list a{border-bottom:1px solid var(--line)}
.contact-list a:hover{border-color:var(--accent);color:var(--accent)}

/* ---------- sub-category chips row ---------- */
.subnav{display:flex;flex-wrap:wrap;gap:10px;margin-top:30px}
.subnav a{font-size:12px;letter-spacing:.06em;padding:8px 14px;border:1px solid rgba(255,255,255,.25);border-radius:2px;color:#DCE7EF}
.subnav a:hover{background:#fff;color:var(--ink);border-color:#fff}

/* ---------- misc ---------- */
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line)}
.tile{background:#fff;padding:clamp(24px,3vw,34px)}
.tile--media{padding:0;display:flex;flex-direction:column}
.tile--media .tile__figure{aspect-ratio:16/10;overflow:hidden;background:var(--mist)}
.tile--media .tile__figure img{width:100%;height:100%;object-fit:cover;transition:transform .6s cubic-bezier(.2,.7,.3,1)}
.tile--media:hover .tile__figure img{transform:scale(1.04)}
.tile--media .tile__body{padding:clamp(20px,2.4vw,26px) clamp(20px,2.4vw,26px) clamp(24px,2.8vw,30px);display:flex;flex-direction:column;flex:1}
.tile--media .tile__body .h-sm{margin-bottom:8px}
.tile--media .link-arrow{margin-top:auto;border:0;padding:16px 0 0}
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:1px;background:var(--line);border:1px solid var(--line)}
.tile h4{font-size:1.15rem;margin-bottom:10px}
.tile p{font-size:14px;color:var(--steel);line-height:1.6}
.tile__num{font-family:var(--display);font-size:1.6rem;color:var(--accent);margin-bottom:14px}

.note-bar{border-left:2px solid var(--accent);padding:14px 0 14px 18px;color:var(--steel);font-size:14px;background:linear-gradient(90deg,rgba(255,90,31,.045),transparent)}

/* ---------- responsive ---------- */
@media (max-width:1080px){
  .cat-grid{grid-template-columns:repeat(3,1fr)}
  .apps{grid-template-columns:repeat(2,1fr)}
  .steps{grid-template-columns:repeat(2,1fr);gap:32px 28px}
  .foot-grid{grid-template-columns:1fr 1fr}
}
@media (max-width:860px){
  .nav,.head-actions .btn{display:none}
  .nav-toggle{display:flex}
  .split{grid-template-columns:1fr}
  .split--rev .split__media{order:0}
  .stat-strip{grid-template-columns:repeat(2,1fr)}
  .stat:nth-child(2){border-right:0}
  .stat:nth-child(1),.stat:nth-child(2){border-bottom:1px solid rgba(255,255,255,.13)}
  .grid-3{grid-template-columns:1fr}
  .form-grid{grid-template-columns:1fr}
  .cat-grid{grid-template-columns:repeat(2,1fr)}
  .topline .wrap span:last-child{display:none}
}
@media (max-width:560px){
  .cat-grid{grid-template-columns:1fr}
  .apps{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr}
  .foot-grid{grid-template-columns:1fr}
  .brand__tag{display:none}
  .hero__cta .btn{width:100%}
  .site-head__inner{height:64px}
}
@media (prefers-reduced-motion:reduce){
  *{animation:none!important;transition:none!important;scroll-behavior:auto!important}
}

/* mobile drawer — anchored to the sticky header so it never sits under it */
.mobile-nav{display:none;position:absolute;top:100%;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);z-index:55;padding:10px var(--gut) 24px;box-shadow:0 24px 40px rgba(11,26,38,.12)}
.mobile-nav.is-open{display:block}
.mobile-nav a{display:block;padding:14px 0;border-bottom:1px solid var(--line);font-size:15px;font-weight:500}
.mobile-nav .btn{margin-top:18px;width:100%}