/* ============================================================
   TELLURIUM — tellurium.tech
   Element 52. Software beyond the ordinary.
   Shared stylesheet for all pages.
   ============================================================ */

:root{
  --ink:#0b0b0f;
  --ink-soft:#1d1d1f;
  --paper:#ffffff;
  --mist:#f5f5f7;
  --gray:#6e6e73;
  --gray-light:#a1a1a6;
  --hairline:#e8e8ed;
  --accent:#0fb3a3;
  --accent-dark:#0b8a7e;
  --accent-glow:#3ddbc9;
  --font-sans:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --font-mono:"SF Mono",SFMono-Regular,ui-monospace,"Cascadia Mono","Segoe UI Mono",Menlo,Consolas,monospace;
  --ease:cubic-bezier(.22,.61,.36,1);
}

*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;}
body{
  font-family:var(--font-sans);
  background:var(--paper);
  color:var(--ink-soft);
  line-height:1.5;
  overflow-x:hidden;
}
img,svg{display:block;max-width:100%;}
a{color:inherit;text-decoration:none;}
::selection{background:var(--accent);color:#fff;}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:4px;}

/* ---------- Type scale ---------- */
.display{
  font-size:clamp(2.6rem,7vw,5.5rem);
  font-weight:600;
  letter-spacing:-0.03em;
  line-height:1.05;
}
.headline{
  font-size:clamp(2rem,4.5vw,3.5rem);
  font-weight:600;
  letter-spacing:-0.025em;
  line-height:1.1;
}
.title{
  font-size:clamp(1.4rem,2.6vw,2rem);
  font-weight:600;
  letter-spacing:-0.02em;
  line-height:1.2;
}
.subhead{
  font-size:clamp(1.1rem,2vw,1.45rem);
  font-weight:400;
  color:var(--gray);
  letter-spacing:-0.01em;
}
.eyebrow{
  font-family:var(--font-mono);
  font-size:0.8rem;
  font-weight:500;
  letter-spacing:0.12em;
  text-transform:uppercase;
  color:var(--accent-dark);
}
.dark .eyebrow{color:var(--accent-glow);}
.dark .subhead{color:var(--gray-light);}

/* ---------- Nav ---------- */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:100;
  backdrop-filter:saturate(180%) blur(20px);
  -webkit-backdrop-filter:saturate(180%) blur(20px);
  background:rgba(255,255,255,0.72);
  border-bottom:1px solid rgba(0,0,0,0.06);
  transition:background .4s var(--ease);
}
.nav.over-dark{
  background:rgba(11,11,15,0.72);
  border-bottom-color:rgba(255,255,255,0.08);
}
.nav-inner{
  max-width:1100px;margin:0 auto;
  display:flex;align-items:center;justify-content:space-between;
  padding:0 24px;height:52px;
}
.brand{
  display:flex;align-items:center;gap:10px;
  font-weight:600;font-size:1rem;letter-spacing:-0.01em;
  color:var(--ink);
  transition:color .4s var(--ease);
}
.nav.over-dark .brand{color:#fff;}
.brand-tile{
  width:30px;height:30px;
  border:1.5px solid currentColor;border-radius:6px;
  display:grid;place-items:center;position:relative;
  font-family:var(--font-mono);font-size:0.85rem;font-weight:600;
}
.brand-tile::before{
  content:"52";
  position:absolute;top:1px;left:3px;
  font-size:0.42rem;font-weight:500;opacity:.7;
}
.nav-links{display:flex;gap:32px;list-style:none;align-items:center;}
.nav-links a{
  font-size:0.85rem;color:var(--ink-soft);opacity:.75;
  transition:opacity .25s,color .4s var(--ease);
}
.nav.over-dark .nav-links a{color:#f5f5f7;}
.nav-links a:hover,.nav-links a[aria-current="page"]{opacity:1;}
.nav-cta{
  font-size:0.8rem;font-weight:500;
  background:var(--ink);color:#fff !important;opacity:1 !important;
  padding:7px 16px;border-radius:99px;
  transition:transform .25s var(--ease),background .4s var(--ease);
}
.nav.over-dark .nav-cta{background:#fff;color:var(--ink) !important;}
.nav-cta:hover{transform:scale(1.04);}

.burger{
  display:none;background:none;border:0;cursor:pointer;
  width:36px;height:36px;position:relative;z-index:102;
}
.burger span{
  position:absolute;left:8px;right:8px;height:1.5px;
  background:var(--ink);transition:all .35s var(--ease);
}
.nav.over-dark .burger span{background:#fff;}
.burger span:nth-child(1){top:14px;}
.burger span:nth-child(2){top:21px;}
.burger.open span:nth-child(1){top:17px;transform:rotate(45deg);}
.burger.open span:nth-child(2){top:17px;transform:rotate(-45deg);}

.mobile-menu{
  position:fixed;inset:0;z-index:101;
  background:rgba(255,255,255,0.92);
  backdrop-filter:blur(24px);-webkit-backdrop-filter:blur(24px);
  display:flex;flex-direction:column;justify-content:center;
  padding:0 40px;gap:8px;
  opacity:0;pointer-events:none;transition:opacity .35s var(--ease);
}
.mobile-menu.open{opacity:1;pointer-events:auto;}
.mobile-menu a{
  font-size:1.8rem;font-weight:600;letter-spacing:-0.02em;
  padding:10px 0;color:var(--ink);
  transform:translateY(14px);opacity:0;
  transition:transform .45s var(--ease),opacity .45s var(--ease);
}
.mobile-menu a.mm-small{font-size:1.05rem;color:var(--gray);font-weight:500;}
.mobile-menu.open a{transform:translateY(0);opacity:1;}
.mobile-menu.open a:nth-child(2){transition-delay:.04s;}
.mobile-menu.open a:nth-child(3){transition-delay:.08s;}
.mobile-menu.open a:nth-child(4){transition-delay:.12s;}
.mobile-menu.open a:nth-child(5){transition-delay:.16s;}
.mobile-menu.open a:nth-child(6){transition-delay:.2s;}
.mobile-menu.open a:nth-child(7){transition-delay:.24s;}
.mobile-menu.open a:nth-child(8){transition-delay:.28s;}

/* ---------- Sections ---------- */
section{padding:110px 24px;}
.wrap{max-width:1100px;margin:0 auto;}
.wrap-narrow{max-width:760px;margin:0 auto;}
.center{text-align:center;}
.dark{background:var(--ink);color:#f5f5f7;}
.mist{background:var(--mist);}

/* ---------- Buttons ---------- */
.cta-row{display:flex;gap:18px;align-items:center;justify-content:center;flex-wrap:wrap;}
.btn{
  display:inline-block;font-size:0.95rem;font-weight:500;
  padding:12px 26px;border-radius:99px;border:0;cursor:pointer;
  font-family:var(--font-sans);
  transition:transform .25s var(--ease),box-shadow .25s var(--ease),background .25s;
}
.btn-solid{background:var(--ink);color:#fff;}
.btn-solid:hover{transform:scale(1.045);box-shadow:0 10px 30px rgba(0,0,0,.18);}
.dark .btn-solid{background:#fff;color:var(--ink);}
.btn-link{color:var(--accent-dark);font-weight:500;font-size:0.95rem;background:none;border:0;cursor:pointer;}
.btn-link::after{content:" →";transition:margin .25s;}
.btn-link:hover::after{margin-left:4px;}
.dark .btn-link{color:var(--accent-glow);}

/* ---------- Home hero ---------- */
.hero{
  min-height:100svh;
  display:flex;flex-direction:column;justify-content:center;align-items:center;
  text-align:center;padding-top:120px;position:relative;
}
.hero-eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:0.8rem;color:var(--gray);
  border:1px solid var(--hairline);border-radius:99px;
  padding:6px 14px;margin-bottom:28px;
}
.hero-eyebrow .dot{
  width:6px;height:6px;border-radius:50%;background:var(--accent);
  animation:pulse 2.2s infinite;
}
@keyframes pulse{
  0%,100%{box-shadow:0 0 0 0 rgba(15,179,163,.45);}
  55%{box-shadow:0 0 0 7px rgba(15,179,163,0);}
}
.hero h1 span{display:block;}
.hero .subhead{max-width:560px;margin:26px auto 38px;}

/* staggered load */
.rise{opacity:0;transform:translateY(26px);animation:rise .9s var(--ease) forwards;}
.rise.d1{animation-delay:.1s;}
.rise.d2{animation-delay:.25s;}
.rise.d3{animation-delay:.4s;}
.rise.d4{animation-delay:.55s;}
@keyframes rise{to{opacity:1;transform:translateY(0);}}

/* element tile — the signature */
.element-tile{
  margin:70px auto 0;width:150px;height:150px;
  border:2px solid var(--ink);border-radius:18px;
  display:flex;flex-direction:column;justify-content:center;align-items:center;
  position:relative;font-family:var(--font-mono);
  background:var(--paper);
  transition:transform .5s var(--ease),box-shadow .5s var(--ease),border-color .5s;
  cursor:default;
}
.element-tile:hover{
  transform:rotate(-3deg) scale(1.05);
  box-shadow:0 24px 60px rgba(15,179,163,.25);
  border-color:var(--accent);
}
.element-tile .num{position:absolute;top:10px;left:14px;font-size:0.8rem;color:var(--gray);}
.element-tile .mass{position:absolute;bottom:10px;right:14px;font-size:0.7rem;color:var(--gray-light);}
.element-tile .sym{font-size:3.2rem;font-weight:600;letter-spacing:-0.02em;line-height:1;}
.element-tile .name{font-size:0.72rem;letter-spacing:0.14em;text-transform:uppercase;color:var(--gray);margin-top:8px;}
.element-tile:hover .sym{color:var(--accent-dark);}

.scroll-hint{
  position:absolute;bottom:28px;left:50%;transform:translateX(-50%);
  width:1.5px;height:44px;overflow:hidden;
}
.scroll-hint::after{
  content:"";position:absolute;left:0;top:-100%;width:100%;height:100%;
  background:var(--gray-light);animation:drip 1.8s infinite var(--ease);
}
@keyframes drip{to{top:100%;}}

/* ---------- Subpage hero ---------- */
.page-hero{
  padding:180px 24px 80px;text-align:center;
}
.page-hero .display{font-size:clamp(2.4rem,6vw,4.4rem);}
.page-hero .subhead{max-width:620px;margin:24px auto 0;}
.page-hero .crumb{
  font-family:var(--font-mono);font-size:0.75rem;color:var(--gray-light);
  margin-bottom:22px;display:block;
}
.page-hero .crumb a:hover{color:var(--accent-dark);}
.page-hero.dark-hero{background:var(--ink);color:#f5f5f7;}
.dark-hero .subhead{color:var(--gray-light);}
.dark-hero .crumb a:hover{color:var(--accent-glow);}

/* ---------- Scroll reveal ---------- */
.reveal{opacity:0;transform:translateY(34px);transition:opacity .8s var(--ease),transform .8s var(--ease);}
.reveal.in{opacity:1;transform:none;}
.reveal.lag1{transition-delay:.12s;}
.reveal.lag2{transition-delay:.24s;}
.reveal.lag3{transition-delay:.36s;}

/* ---------- Services: the periodic grid ---------- */
.services-head{max-width:640px;margin:0 auto 70px;}
.periodic{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;}
.p-card{
  border:1px solid var(--hairline);border-radius:22px;
  padding:36px 30px 34px;background:var(--paper);
  transition:transform .45s var(--ease),box-shadow .45s var(--ease),border-color .45s;
  position:relative;overflow:hidden;display:block;
}
.p-card::before{
  content:attr(data-num);
  position:absolute;top:-24px;right:-6px;
  font-family:var(--font-mono);font-weight:600;
  font-size:7rem;line-height:1;color:var(--mist);
  transition:color .45s,transform .6s var(--ease);
  z-index:0;pointer-events:none;
}
.p-card:hover{
  transform:translateY(-8px);
  box-shadow:0 30px 70px rgba(0,0,0,.09);
  border-color:transparent;
}
.p-card:hover::before{color:#e4f7f4;transform:translateY(6px);}
.p-card>*{position:relative;z-index:1;}
.p-sym{
  width:58px;height:58px;border:1.5px solid var(--ink);border-radius:12px;
  display:grid;place-items:center;
  font-family:var(--font-mono);font-size:1.35rem;font-weight:600;
  margin-bottom:26px;background:var(--paper);color:var(--ink);
  transition:background .35s,color .35s,border-color .35s,transform .45s var(--ease);
}
.p-card:hover .p-sym{background:var(--ink);color:#fff;transform:rotate(-4deg);}
.p-card h3{font-size:1.35rem;font-weight:600;letter-spacing:-0.02em;margin-bottom:12px;}
.p-card p{font-size:0.95rem;color:var(--gray);margin-bottom:22px;}
.p-card .tags{display:flex;flex-wrap:wrap;gap:8px;}
.p-card .tags span{
  font-family:var(--font-mono);font-size:0.68rem;
  border:1px solid var(--hairline);border-radius:99px;
  padding:4px 10px;color:var(--gray);
}
.p-card .more{
  display:inline-block;margin-top:20px;font-size:0.88rem;font-weight:500;color:var(--accent-dark);
}
.p-card .more::after{content:" →";transition:margin .25s;}
.p-card:hover .more::after{margin-left:4px;}

/* ---------- Split rows (subpage content) ---------- */
.split{
  display:grid;grid-template-columns:1fr 1fr;gap:70px;align-items:center;
}
.split + .split{margin-top:100px;}
.split h2,.split h3{margin:12px 0 18px;}
.split p{color:var(--gray);margin-bottom:16px;}
.dark .split p{color:var(--gray-light);}
.split.flip>div:first-child{order:2;}

.check-list{list-style:none;margin-top:8px;}
.check-list li{
  position:relative;padding:10px 0 10px 34px;
  border-bottom:1px solid var(--hairline);font-size:0.95rem;
}
.check-list li:last-child{border-bottom:0;}
.check-list li::before{
  content:"✓";position:absolute;left:4px;top:10px;
  color:var(--accent-dark);font-weight:600;
}
.dark .check-list li{border-bottom-color:rgba(255,255,255,.1);color:#d5d5da;}
.dark .check-list li::before{color:var(--accent-glow);}

/* decorative panel for split rows */
.panel{
  border-radius:22px;min-height:340px;position:relative;overflow:hidden;
  display:flex;align-items:center;justify-content:center;
}
.panel-teal{background:radial-gradient(120% 120% at 20% 10%,#0fb3a3 0%,#083f39 55%,#0b0b0f 100%);}
.panel-slate{background:radial-gradient(120% 120% at 80% 0%,#4a4a58 0%,#1c1c23 60%,#0b0b0f 100%);}
.panel-deep{background:radial-gradient(120% 120% at 50% 100%,#0b8a7e 0%,#11202a 60%,#0b0b0f 100%);}
.panel-mist{background:var(--mist);}
.panel .big-sym{
  font-family:var(--font-mono);font-weight:600;color:rgba(255,255,255,.9);
  font-size:clamp(4rem,9vw,7rem);letter-spacing:-0.03em;
}
.panel-mist .big-sym{color:var(--ink);}
.panel .big-sym small{
  display:block;font-size:0.85rem;letter-spacing:0.14em;text-transform:uppercase;
  color:rgba(255,255,255,.55);text-align:center;margin-top:10px;font-weight:500;
}
.panel-mist .big-sym small{color:var(--gray);}

/* ---------- Process steps ---------- */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:22px;margin-top:64px;}
.step{
  border:1px solid var(--hairline);border-radius:18px;padding:28px 24px;
  background:var(--paper);
  transition:transform .4s var(--ease),box-shadow .4s var(--ease);
}
.step:hover{transform:translateY(-6px);box-shadow:0 20px 50px rgba(0,0,0,.08);}
.step .n{
  font-family:var(--font-mono);font-size:0.8rem;color:var(--accent-dark);
  display:block;margin-bottom:14px;
}
.step b{display:block;font-size:1.05rem;font-weight:600;letter-spacing:-0.01em;margin-bottom:8px;}
.step p{font-size:0.88rem;color:var(--gray);}

/* ---------- FAQ ---------- */
.faq{max-width:760px;margin:60px auto 0;}
.faq details{
  border-bottom:1px solid var(--hairline);
}
.faq summary{
  cursor:pointer;list-style:none;position:relative;
  padding:22px 44px 22px 0;font-size:1.05rem;font-weight:500;letter-spacing:-0.01em;
}
.faq summary::-webkit-details-marker{display:none;}
.faq summary::after{
  content:"+";position:absolute;right:6px;top:50%;transform:translateY(-50%);
  font-size:1.4rem;font-weight:300;color:var(--gray);
  transition:transform .35s var(--ease);
}
.faq details[open] summary::after{transform:translateY(-50%) rotate(45deg);color:var(--accent-dark);}
.faq details p{padding:0 0 22px;color:var(--gray);font-size:0.95rem;max-width:640px;}

/* ---------- Gochi feature (dark) ---------- */
.feature .wrap{display:grid;grid-template-columns:1fr 1fr;gap:70px;align-items:center;}
.feature h2{margin:14px 0 20px;}
.feature .subhead{margin-bottom:30px;}
.feature-stats{display:flex;gap:40px;margin-top:38px;flex-wrap:wrap;}
.stat b{display:block;font-size:2rem;font-weight:600;letter-spacing:-0.02em;color:#fff;}
.stat small{font-size:0.8rem;color:var(--gray-light);}

/* pure-CSS product mockup */
.mockup{
  background:#141419;border:1px solid #26262e;border-radius:18px;
  overflow:hidden;box-shadow:0 40px 100px rgba(0,0,0,.5);
  transform:perspective(1200px) rotateY(-6deg) rotateX(2deg);
  transition:transform .8s var(--ease);
}
.mockup:hover{transform:perspective(1200px) rotateY(0) rotateX(0);}
.mock-bar{display:flex;align-items:center;gap:6px;padding:11px 14px;border-bottom:1px solid #26262e;}
.mock-bar i{width:9px;height:9px;border-radius:50%;background:#2e2e38;}
.mock-bar .url{margin-left:auto;font-family:var(--font-mono);font-size:0.65rem;color:#5c5c68;}
.mock-body{display:grid;grid-template-columns:64px 1fr;min-height:280px;}
.mock-side{border-right:1px solid #26262e;padding:16px 0;display:flex;flex-direction:column;align-items:center;gap:14px;}
.mock-side i{width:26px;height:26px;border-radius:8px;background:#22222a;}
.mock-side i:first-child{background:var(--accent);}
.mock-main{padding:18px;display:flex;flex-direction:column;gap:14px;}
.mock-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;}
.mock-cards i{height:52px;border-radius:10px;background:#1c1c23;border:1px solid #26262e;position:relative;overflow:hidden;}
.mock-cards i::after{
  content:"";position:absolute;left:10px;top:10px;width:40%;height:6px;border-radius:3px;background:#2e2e38;
}
.mock-chart{
  flex:1;border:1px solid #26262e;border-radius:12px;background:#1c1c23;
  display:flex;align-items:flex-end;gap:8px;padding:16px;min-height:130px;
}
.mock-chart b{
  flex:1;border-radius:4px 4px 0 0;background:linear-gradient(to top,var(--accent-dark),var(--accent-glow));
  height:calc(var(--h)*1%);
  transform:scaleY(0);transform-origin:bottom;
  transition:transform 1s var(--ease);
}
.in .mock-chart b{transform:scaleY(1);}
.in .mock-chart b:nth-child(2){transition-delay:.08s;}
.in .mock-chart b:nth-child(3){transition-delay:.16s;}
.in .mock-chart b:nth-child(4){transition-delay:.24s;}
.in .mock-chart b:nth-child(5){transition-delay:.32s;}
.in .mock-chart b:nth-child(6){transition-delay:.4s;}
.in .mock-chart b:nth-child(7){transition-delay:.48s;}

/* ---------- Work grid ---------- */
.work-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-top:64px;}
.w-card{
  border-radius:22px;padding:34px 30px;min-height:300px;
  display:flex;flex-direction:column;justify-content:flex-end;
  position:relative;overflow:hidden;color:#fff;
  transition:transform .45s var(--ease),box-shadow .45s var(--ease);
}
.w-card:hover{transform:translateY(-8px);box-shadow:0 30px 70px rgba(0,0,0,.22);}
.w-card::before{content:"";position:absolute;inset:0;transition:transform .7s var(--ease);}
.w-card:hover::before{transform:scale(1.05);}
.w1::before{background:radial-gradient(120% 120% at 20% 10%,#0fb3a3 0%,#083f39 55%,#0b0b0f 100%);}
.w2::before{background:radial-gradient(120% 120% at 80% 0%,#4a4a58 0%,#1c1c23 60%,#0b0b0f 100%);}
.w3::before{background:radial-gradient(120% 120% at 50% 100%,#0b8a7e 0%,#11202a 60%,#0b0b0f 100%);}
.w-card>*{position:relative;}
.w-card .kind{
  font-family:var(--font-mono);font-size:0.68rem;letter-spacing:0.12em;
  text-transform:uppercase;color:rgba(255,255,255,.65);margin-bottom:10px;
}
.w-card h3{font-size:1.5rem;font-weight:600;letter-spacing:-0.02em;margin-bottom:8px;}
.w-card p{font-size:0.9rem;color:rgba(255,255,255,.75);}

/* ---------- Case study rows (work page) ---------- */
.case{
  display:grid;grid-template-columns:1fr 1fr;gap:70px;align-items:center;
  padding:90px 0;border-bottom:1px solid var(--hairline);
}
.case:last-of-type{border-bottom:0;}
.case .kind{
  font-family:var(--font-mono);font-size:0.72rem;letter-spacing:0.12em;
  text-transform:uppercase;color:var(--accent-dark);margin-bottom:12px;display:block;
}
.case h2{margin-bottom:16px;}
.case p{color:var(--gray);margin-bottom:14px;}
.case .tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:22px;}
.case .tags span{
  font-family:var(--font-mono);font-size:0.68rem;
  border:1px solid var(--hairline);border-radius:99px;
  padding:4px 10px;color:var(--gray);
}
.case.flip>div:first-child{order:2;}

/* ---------- Tech strip ---------- */
.strip{
  border-top:1px solid var(--hairline);border-bottom:1px solid var(--hairline);
  padding:26px 0;overflow:hidden;white-space:nowrap;background:var(--paper);
}
.strip-track{display:inline-flex;gap:56px;animation:marquee 30s linear infinite;padding-right:56px;}
.strip span{
  font-family:var(--font-mono);font-size:0.85rem;color:var(--gray);
  display:inline-flex;align-items:center;gap:56px;
}
.strip span::after{content:"·";color:var(--accent);}
@keyframes marquee{to{transform:translateX(-50%);}}
.strip:hover .strip-track{animation-play-state:paused;}

/* ---------- Principles ---------- */
.principles{display:grid;grid-template-columns:repeat(3,1fr);gap:56px;margin-top:70px;text-align:left;}
.pr b{display:block;font-size:1.05rem;font-weight:600;letter-spacing:-0.01em;margin-bottom:10px;color:#fff;}
.pr p{font-size:0.92rem;color:var(--gray-light);}
.pr .tick{
  width:34px;height:34px;border-radius:50%;
  border:1px solid rgba(255,255,255,.2);
  display:grid;place-items:center;margin-bottom:18px;
  color:var(--accent-glow);font-size:0.9rem;
}
.light-pr .pr b{color:var(--ink);}
.light-pr .pr p{color:var(--gray);}
.light-pr .pr .tick{border-color:var(--hairline);color:var(--accent-dark);}

/* ---------- CTA band ---------- */
.cta-band{text-align:center;}
.cta-band h2{margin-bottom:18px;}
.cta-band .subhead{max-width:520px;margin:0 auto 40px;}
.contact-mail{
  font-size:clamp(1.2rem,3vw,1.8rem);font-weight:600;letter-spacing:-0.02em;
  color:var(--accent-dark);border-bottom:2px solid transparent;
  transition:border-color .3s;
}
.contact-mail:hover{border-color:var(--accent-dark);}
.dark .contact-mail{color:var(--accent-glow);}
.dark .contact-mail:hover{border-color:var(--accent-glow);}

/* ---------- Contact form ---------- */
.form-card{
  max-width:640px;margin:0 auto;text-align:left;
}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px;}
.field{display:flex;flex-direction:column;gap:8px;}
.field.full{grid-column:1/-1;}
.field label{font-size:0.82rem;font-weight:500;color:var(--ink-soft);}
.field input,.field select,.field textarea{
  font-family:var(--font-sans);font-size:0.95rem;color:var(--ink);
  background:var(--paper);border:1px solid var(--hairline);border-radius:12px;
  padding:13px 16px;width:100%;
  transition:border-color .25s,box-shadow .25s;
  appearance:none;-webkit-appearance:none;
}
.field textarea{min-height:140px;resize:vertical;}
.field input:focus,.field select:focus,.field textarea:focus{
  outline:none;border-color:var(--accent);
  box-shadow:0 0 0 4px rgba(15,179,163,.14);
}
.field select{
  background-image:url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%236e6e73' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat:no-repeat;background-position:right 16px center;
}
.form-foot{grid-column:1/-1;display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;margin-top:6px;}
.form-foot small{color:var(--gray-light);font-size:0.78rem;}
.hp{position:absolute;left:-9999px;opacity:0;height:0;width:0;overflow:hidden;}
.form-note{
  display:none;margin:0 0 26px;padding:14px 18px;border-radius:12px;
  font-size:0.9rem;font-weight:500;
}
.form-note.ok{display:block;background:#e4f7f4;color:var(--accent-dark);}
.form-note.err{display:block;background:#fdecec;color:#b3261e;}

/* ---------- Footer ---------- */
footer{
  background:var(--ink);color:var(--gray-light);
  padding:64px 24px 40px;font-size:0.82rem;
}
.foot-inner{max-width:1100px;margin:0 auto;}
.foot-top{
  display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:40px;
  padding-bottom:44px;border-bottom:1px solid rgba(255,255,255,.09);
}
.foot-brand{color:#fff;font-weight:600;font-size:1rem;margin-bottom:10px;display:flex;align-items:center;gap:10px;}
.foot-brand .brand-tile{width:26px;height:26px;font-size:0.75rem;border-radius:5px;}
.type-line{font-family:var(--font-mono);font-size:0.78rem;color:var(--gray);}
.type-line .cursor{
  display:inline-block;width:7px;height:13px;background:var(--accent-glow);
  vertical-align:-2px;margin-left:3px;animation:blink 1.1s steps(1) infinite;
}
@keyframes blink{50%{opacity:0;}}
.foot-col b{
  display:block;color:#fff;font-size:0.8rem;font-weight:600;
  letter-spacing:0.06em;text-transform:uppercase;margin-bottom:16px;
}
.foot-col ul{list-style:none;}
.foot-col li{margin-bottom:10px;}
.foot-col a:hover{color:#fff;}
.foot-bottom{
  display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap;
  padding-top:28px;color:var(--gray);
}

/* ---------- Responsive ---------- */
@media(max-width:900px){
  .periodic,.work-grid,.principles{grid-template-columns:1fr 1fr;}
  .steps{grid-template-columns:1fr 1fr;}
  .feature .wrap,.split,.case{grid-template-columns:1fr;gap:50px;}
  .split.flip>div:first-child,.case.flip>div:first-child{order:0;}
  .mockup{transform:none;}
  .foot-top{grid-template-columns:1fr 1fr;}
}
@media(max-width:640px){
  section{padding:80px 20px;}
  .page-hero{padding:150px 20px 60px;}
  .nav-links{display:none;}
  .burger{display:block;}
  .periodic,.work-grid,.principles,.steps,.form-grid{grid-template-columns:1fr;}
  .feature-stats{gap:26px;}
  .element-tile{width:126px;height:126px;}
  .element-tile .sym{font-size:2.6rem;}
  .foot-top{grid-template-columns:1fr;}
  .case{padding:64px 0;}
  .panel{min-height:240px;}
}

/* ---------- Reduced motion ---------- */
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation:none !important;transition:none !important;}
  .reveal,.rise{opacity:1 !important;transform:none !important;}
  .in .mock-chart b{transform:scaleY(1);}
  html{scroll-behavior:auto;}
}

/* ---------- Nav services dropdown ---------- */
.has-drop{position:relative;}
.has-drop>a::after{
  content:"";display:inline-block;margin-left:6px;
  width:6px;height:6px;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;
  transform:rotate(45deg) translateY(-2px);opacity:.6;
}
.drop{
  position:absolute;top:calc(100% + 10px);left:50%;transform:translate(-50%,6px);
  min-width:230px;padding:8px;
  background:rgba(255,255,255,0.85);
  backdrop-filter:saturate(180%) blur(20px);
  -webkit-backdrop-filter:saturate(180%) blur(20px);
  border:1px solid rgba(0,0,0,0.08);border-radius:16px;
  box-shadow:0 20px 50px rgba(0,0,0,.14);
  opacity:0;visibility:hidden;
  transition:opacity .25s var(--ease),transform .25s var(--ease),visibility .25s;
}
.has-drop:hover .drop,
.has-drop:focus-within .drop{
  opacity:1;visibility:visible;transform:translate(-50%,0);
}
.drop a{
  display:block;padding:11px 14px;border-radius:10px;
  font-size:0.85rem;color:var(--ink-soft) !important;opacity:1 !important;
}
.drop a:hover{background:rgba(0,0,0,0.05);}
.nav.over-dark .drop{
  background:rgba(20,20,25,0.85);
  border-color:rgba(255,255,255,0.1);
}
.nav.over-dark .drop a{color:#f5f5f7 !important;}
.nav.over-dark .drop a:hover{background:rgba(255,255,255,0.08);}