/* ============================================================
   Tessera Security — marketing site stylesheet
   Converged token layer (paper / petrol / brass), IBM Plex.
   Built from the reviewed 24 Sep mocks; fonts self-hosted,
   plus accessibility, mobile menu, pricing table and form styles.
   ============================================================ */

/* 1. FONTS — self-hosted, cached once site-wide --------------- */
@font-face{font-family:'IBM Plex Sans';font-style:normal;font-weight:400;font-display:swap;src:url('/assets/fonts/plex-sans-400.woff2') format('woff2')}
@font-face{font-family:'IBM Plex Sans';font-style:normal;font-weight:500;font-display:swap;src:url('/assets/fonts/plex-sans-500.woff2') format('woff2')}
@font-face{font-family:'IBM Plex Sans';font-style:normal;font-weight:600;font-display:swap;src:url('/assets/fonts/plex-sans-600.woff2') format('woff2')}
@font-face{font-family:'IBM Plex Sans';font-style:normal;font-weight:700;font-display:swap;src:url('/assets/fonts/plex-sans-700.woff2') format('woff2')}
@font-face{font-family:'IBM Plex Sans';font-style:italic;font-weight:400;font-display:swap;src:url('/assets/fonts/plex-sans-italic-400.woff2') format('woff2')}
@font-face{font-family:'IBM Plex Mono';font-style:normal;font-weight:400;font-display:swap;src:url('/assets/fonts/plex-mono-400.woff2') format('woff2')}

/* 2. TOKENS --------------------------------------------------- */
:root{
  --paper:#F6F4EF; --surface:#FFFFFF; --surface-2:#FBFAF6;
  --ink:#22262B; --muted:#5A6068; --faint:#686E77;
  --line:#E4E1D8; --line-strong:#C9C5BA;
  --accent:#14555F; --accent-strong:#0C3F48; --accent-soft:#E7EFEF; --on-accent:#F6F4EF;
  --brass:#7C5E1E; --brass-tint:#EFE7D4;
  --panel:#0C3F48; --panel-2:#0E4a54; --panel-fg:#EAF2F1; --panel-muted:#A9C4C6;
  --good:#256B41; --warn:#A8381C;
  --sans:'IBM Plex Sans',system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,Menlo,Consolas,monospace;
  --r:10px; --r-sm:7px; --r-tile:3px;
  --shadow:0 1px 2px rgba(20,40,45,.05),0 18px 44px -20px rgba(20,40,45,.20);
  --shadow-sm:0 1px 2px rgba(20,40,45,.04),0 8px 22px -14px rgba(20,40,45,.16);
  --maxw:1120px;
}
:root[data-theme="dark"]{
  --paper:#16181B; --surface:#1E2125; --surface-2:#1A1D20;
  --ink:#E8E6E1; --muted:#A6A9AD; --faint:#8B8E93;
  --line:#2A2D31; --line-strong:#383C41;
  --accent:#6FB7C0; --accent-strong:#A7D6DC; --accent-soft:#16323A; --on-accent:#0E2A2E;
  --brass:#D3A94E; --brass-tint:#2A2416;
  --panel:#12303A; --panel-2:#123c46; --panel-fg:#EAF2F1; --panel-muted:#8FB3B6;
  --good:#6BC28E; --warn:#F0997E;
  --shadow:0 1px 2px rgba(0,0,0,.4),0 22px 50px -22px rgba(0,0,0,.6);
  --shadow-sm:0 1px 2px rgba(0,0,0,.35),0 12px 28px -18px rgba(0,0,0,.5);
}

/* 3. BASE + ACCESSIBILITY ------------------------------------- */
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);font-size:16px;line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
img,svg{max-width:100%}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:4px}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.skip{position:absolute;left:-9999px;top:0;z-index:100;background:var(--accent);color:var(--on-accent);padding:10px 16px;border-radius:0 0 var(--r-sm) 0;font-weight:600}
.skip:focus{left:0;text-decoration:none}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}
}

.tmark{display:inline-grid;grid-template-columns:1fr 1fr;gap:3px}
.tmark i{border-radius:var(--r-tile);background:currentColor}
.tmark i.o{background:transparent;box-shadow:inset 0 0 0 2px currentColor}

/* 4. HEADER --------------------------------------------------- */
header.top{position:sticky;top:0;z-index:50;background:color-mix(in srgb,var(--paper) 88%,transparent);
  backdrop-filter:saturate(120%) blur(8px);border-bottom:1px solid var(--line)}
.bar{display:flex;align-items:center;gap:26px;height:64px}
.brand{display:flex;align-items:center;gap:10px;color:var(--accent);font-weight:600;font-size:18px}
.brand:hover{text-decoration:none}
.brand .tmark{grid-template-columns:12px 12px}.brand .tmark i{width:12px;height:12px}
.brand b{color:var(--ink);font-weight:700}.brand span{color:var(--faint);font-weight:500}
.nav{display:flex;gap:22px;margin-left:8px}
.nav a{color:var(--muted);font-size:14.5px;font-weight:500}
.nav a:hover{color:var(--ink);text-decoration:none}
.nav a[aria-current="page"]{color:var(--ink)}
.bar .right{margin-left:auto;display:flex;align-items:center;gap:14px}
.tgl{background:none;border:1px solid var(--line-strong);color:var(--muted);width:34px;height:34px;border-radius:var(--r-sm);cursor:pointer;display:grid;place-items:center}
.tgl:hover{color:var(--ink)}
.btn{display:inline-flex;align-items:center;gap:8px;font:inherit;font-size:14.5px;font-weight:600;
  border-radius:var(--r-sm);padding:10px 18px;cursor:pointer;border:1px solid transparent;text-decoration:none;white-space:nowrap}
.btn:hover{text-decoration:none}
.btn.primary{background:var(--accent);color:var(--on-accent)}.btn.primary:hover{background:var(--accent-strong)}
.btn.line{background:transparent;color:var(--ink);border-color:var(--line-strong)}.btn.line:hover{border-color:var(--ink)}
.btn.ghost{background:transparent;color:var(--accent);padding-left:6px;padding-right:6px}
.btn.big{font-size:15.5px;padding:13px 24px}
.menub{display:none}

/* mobile menu panel */
.mobnav{display:none;border-bottom:1px solid var(--line);background:var(--paper)}
.mobnav[data-open="true"]{display:block}
.mobnav a{display:block;padding:13px 24px;color:var(--ink);font-size:16px;border-top:1px solid var(--line)}
.mobnav a:hover{background:var(--accent-soft);color:var(--accent);text-decoration:none}
.mobnav .row{display:flex;gap:12px;padding:16px 24px 20px}
.mobnav .row .btn{flex:1;justify-content:center}

/* 5. HEADINGS / SECTIONS -------------------------------------- */
.eyebrow{display:inline-flex;align-items:center;gap:8px;font-size:12px;font-weight:700;letter-spacing:.12em;text-transform:uppercase;color:var(--brass)}
.eyebrow::before{content:"";width:18px;height:2px;background:var(--brass);border-radius:2px}
h1,h2,h3{letter-spacing:-.02em;line-height:1.1;margin:0}
h1{font-size:clamp(34px,5vw,52px);font-weight:700}
h2{font-size:clamp(26px,3.4vw,36px);font-weight:700}
h3{font-size:19px;font-weight:600;letter-spacing:-.01em}
.lede{font-size:clamp(17px,1.7vw,20px);color:var(--muted);line-height:1.55}
section{padding:84px 0}
.sec-head{max-width:640px;margin:0 0 40px}
.sec-head h2{margin:12px 0 14px}
.sec-head p{margin:0;color:var(--muted);font-size:17px}

/* 6. HERO ----------------------------------------------------- */
.hero{padding:70px 0 40px}
.hero-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center}
.hero h1{margin:16px 0 20px}
.hero .lede{max-width:46ch}
.hero .cta{display:flex;gap:12px;margin-top:30px;flex-wrap:wrap}
.hero .microtrust{margin-top:22px;font-size:13px;color:var(--faint);display:flex;gap:8px;align-items:center}
.hero .microtrust b{color:var(--muted);font-weight:600}

/* golden-thread diagram card */
.threadcard{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--shadow);padding:22px 22px 18px}
.threadcard .cap{display:flex;align-items:center;justify-content:space-between;margin-bottom:14px}
.threadcard .cap .t{font-size:12px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--faint)}
.threadcard .cap .live{font-size:11.5px;color:var(--good);font-weight:600;display:inline-flex;gap:6px;align-items:center}
.threadcard .cap .live::before{content:"";width:7px;height:7px;border-radius:50%;background:var(--good)}
.tnode{fill:var(--surface-2);stroke:var(--line-strong)}
.tnode.focus{fill:var(--accent-soft);stroke:var(--accent)}
.tedge{stroke:var(--line-strong)}
.tlabel{fill:var(--ink);font:600 12px var(--sans)}
.ttag{fill:var(--faint);font:400 10px var(--mono)}

/* 7. CARDS ---------------------------------------------------- */
.cards{display:grid;gap:20px}
.cards.c3{grid-template-columns:repeat(3,1fr)}
.cards.c4{grid-template-columns:repeat(4,1fr)}
.cards.c2{grid-template-columns:1fr 1fr}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:24px;box-shadow:var(--shadow-sm)}
.card .ic{width:38px;height:38px;border-radius:9px;background:var(--accent-soft);color:var(--accent);display:grid;place-items:center;margin-bottom:14px}
.card .ic svg{width:20px;height:20px}
.card h3{margin-bottom:7px}
.card p{margin:0;color:var(--muted);font-size:15px}
.card .tag{display:inline-block;margin-top:12px;font-size:11.5px;font-weight:600;color:var(--brass);background:var(--brass-tint);border-radius:20px;padding:2px 10px}

/* 8. DIFFERENTIATOR SPLIT ------------------------------------- */
.vs{display:grid;grid-template-columns:1fr 1fr;gap:0;border:1px solid var(--line);border-radius:var(--r);overflow:hidden;box-shadow:var(--shadow-sm)}
.vs > div{padding:26px 28px}
.vs .them{background:var(--surface-2)}
.vs .us{background:var(--surface);border-left:3px solid var(--accent)}
.vs .k{font-size:12px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;margin-bottom:12px}
.vs .them .k{color:var(--faint)}.vs .us .k{color:var(--accent)}
.vs ul{margin:0;padding:0;list-style:none}
.vs li{display:flex;gap:10px;font-size:15px;color:var(--muted);padding:7px 0;border-top:1px solid var(--line)}
.vs li:first-child{border-top:0}
.vs .us li{color:var(--ink)}
.vs li .m{flex:none;color:var(--accent);font-weight:700}
.vs .them li .m{color:var(--faint)}

/* 9. STEPS ---------------------------------------------------- */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;counter-reset:s}
.step{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:22px;position:relative}
.step .n{width:26px;height:26px;border-radius:50%;background:var(--accent);color:var(--on-accent);font-size:13px;font-weight:700;display:grid;place-items:center;margin-bottom:12px}
.step h3{margin-bottom:6px;font-size:16.5px}
.step p{margin:0;color:var(--muted);font-size:14px}

/* 10. TRUST STRIP --------------------------------------------- */
.trust{display:grid;grid-template-columns:repeat(5,1fr);gap:14px}
.trust .t{border:1px solid var(--line);border-radius:var(--r-sm);padding:16px;background:var(--surface)}
.trust .t .h{font-weight:600;font-size:14.5px;margin-bottom:4px;display:flex;align-items:center;gap:7px}
.trust .t .h .d{width:8px;height:8px;border-radius:var(--r-tile);background:var(--accent);flex:none}
.trust .t p{margin:0;font-size:12.5px;color:var(--faint);line-height:1.45}

/* 11. PRODUCTS ------------------------------------------------ */
.prod{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.prodcard{border:1px solid var(--line);border-radius:var(--r);padding:24px;background:var(--surface)}
.prodcard.live{border-color:var(--accent);box-shadow:var(--shadow-sm)}
.prodcard .st{font-size:11.5px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;padding:2px 9px;border-radius:20px;display:inline-block;margin-bottom:12px}
.prodcard.live .st{color:var(--good);background:var(--accent-soft)}
.prodcard .st.soon{color:var(--faint);background:var(--surface-2)}
.prodcard h3{margin-bottom:6px}.prodcard p{margin:0;color:var(--muted);font-size:14.5px}

/* 12. CTA BAND ------------------------------------------------ */
.ctaband{background:var(--panel);color:var(--panel-fg);border-radius:16px;padding:52px 48px;text-align:center;position:relative;overflow:hidden}
.ctaband .bgm{position:absolute;inset:0;opacity:.5;pointer-events:none}
.ctaband h2{color:var(--panel-fg);margin-bottom:12px}
.ctaband p{color:var(--panel-muted);max-width:52ch;margin:0 auto 26px;font-size:17px}
.ctaband .btn.primary{background:var(--panel-fg);color:var(--panel)}
.ctaband .btn.primary:hover{background:#fff}
.ctaband .btn.line{color:var(--panel-fg);border-color:rgba(255,255,255,.3)}
.ctaband .note{margin-top:16px;font-size:12.5px;color:var(--panel-muted)}

/* 13. PRICING TIERS TABLE (added per decision 2) -------------- */
.tiers{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:8px}
.tier{border:1px solid var(--line);border-radius:var(--r);padding:22px;background:var(--surface);display:flex;flex-direction:column}
.tier.feature{border-color:var(--accent);box-shadow:var(--shadow-sm)}
.tier .plan{font-size:12px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--faint)}
.tier.feature .plan{color:var(--accent)}
.tier .price{font-size:30px;font-weight:700;letter-spacing:-.02em;margin:10px 0 2px}
.tier .price .per{font-size:14px;font-weight:500;color:var(--faint)}
.tier .sub{font-size:13px;color:var(--muted);margin:0 0 14px;min-height:34px}
.tier ul{list-style:none;margin:0 0 18px;padding:0}
.tier li{display:flex;gap:9px;font-size:13.5px;color:var(--ink);padding:6px 0;border-top:1px solid var(--line)}
.tier li:first-child{border-top:0}
.tier li .m{flex:none;color:var(--accent);font-weight:700}
.tier .foot{margin-top:auto}
.tier .foot .btn{width:100%;justify-content:center}
.pricenote{margin-top:16px;color:var(--faint);font-size:13.5px}
.pricenote b{color:var(--muted)}

/* 14. REQUEST FORM -------------------------------------------- */
.reqgrid{display:grid;grid-template-columns:1.15fr .85fr;gap:40px;align-items:start}
.formcard{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:30px;box-shadow:var(--shadow-sm)}
.fld{margin-bottom:18px}
.fld label{display:block;font-size:13.5px;font-weight:600;color:var(--ink);margin-bottom:7px}
.fld label .opt{color:var(--faint);font-weight:400}
.fld input,.fld textarea,.fld select{width:100%;box-sizing:border-box;font:inherit;font-size:15px;color:var(--ink);background:var(--surface);border:1px solid var(--line-strong);border-radius:8px;padding:11px 13px}
.fld textarea{min-height:96px;resize:vertical}
.fld input:focus,.fld textarea:focus,.fld select:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}
.fld .err{color:var(--warn);font-size:12.5px;margin:6px 0 0;display:none}
.fld.invalid input,.fld.invalid textarea{border-color:var(--warn)}
.fld.invalid .err{display:block}
.hp{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}
.aside .box{background:var(--surface-2);border:1px solid var(--line);border-radius:var(--r);padding:22px;margin-bottom:16px}
.aside h4{margin:0 0 10px;font-size:14.5px}
.aside ol{margin:0;padding-left:18px;color:var(--muted);font-size:14px;line-height:1.7}
.aside .sec-note{font-size:12.5px;color:var(--faint);line-height:1.5}
.okmsg{display:none;background:var(--accent-soft);border:1px solid var(--accent);border-radius:var(--r);padding:22px;color:var(--ink)}
.okmsg.show{display:block}
.okmsg h3{margin:0 0 6px;color:var(--accent-strong)}
.formerr{display:none;background:color-mix(in srgb,var(--warn) 12%,transparent);border:1px solid var(--warn);border-radius:var(--r);padding:14px 16px;color:var(--ink);font-size:14px;margin-bottom:16px}
.formerr.show{display:block}

/* 15. PROSE (privacy / context / contact / terms) ------------- */
.prose{max-width:760px}
.prose h2{font-size:22px;margin:36px 0 6px}
.prose h3{font-size:16px;margin:22px 0 4px}
.prose p{margin:12px 0;color:var(--ink)}
.prose ul{margin:12px 0;padding-left:22px;color:var(--ink)}
.prose li{margin:7px 0}
.prose .muted{color:var(--muted)}
.prose table{width:100%;border-collapse:collapse;margin:16px 0;font-size:14.5px}
.prose th,.prose td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--line);vertical-align:top}
.prose th{font-family:var(--mono);font-size:12px;color:var(--faint);font-weight:400}
.prose .updated{color:var(--faint);font-size:14px;margin-top:6px}
.prose .callout{background:var(--surface-2);border:1px solid var(--line);border-radius:var(--r);padding:16px 18px;font-size:14px;color:var(--muted);margin:18px 0}
.detailgrid{display:grid;gap:10px;max-width:520px;margin-top:18px}
.detailgrid div{display:grid;grid-template-columns:170px 1fr;gap:10px;align-items:baseline}
.detailgrid .dk{font-family:var(--mono);font-size:12.5px;color:var(--faint)}

/* 16. FOOTER -------------------------------------------------- */
footer{border-top:1px solid var(--line);padding:48px 0 40px;margin-top:20px}
.foot{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:28px}
.foot .about{max-width:30ch}
.foot .about p{color:var(--muted);font-size:13.5px;margin:12px 0 0}
.foot .col h4{font-size:11.5px;letter-spacing:.08em;text-transform:uppercase;color:var(--faint);margin:0 0 12px}
.foot .col a{display:block;color:var(--muted);font-size:14px;padding:4px 0}
.foot .col a:hover{color:var(--ink)}
.foot-btm{border-top:1px solid var(--line);margin-top:34px;padding-top:20px;display:flex;justify-content:space-between;color:var(--faint);font-size:12.5px;flex-wrap:wrap;gap:8px}

/* 17. RESPONSIVE ---------------------------------------------- */
@media (max-width:900px){
  .nav{display:none} .menub{display:grid} .bar .right .btn.line{display:none}
  .hero-grid{grid-template-columns:1fr;gap:34px} .hero .threadcard{order:2}
  .vs{grid-template-columns:1fr} .steps{grid-template-columns:1fr 1fr}
  .trust{grid-template-columns:1fr 1fr} .prod{grid-template-columns:1fr}
  .cards.c3{grid-template-columns:1fr} .cards.c4{grid-template-columns:1fr 1fr} .foot{grid-template-columns:1fr 1fr}
  .tiers{grid-template-columns:1fr 1fr} .reqgrid{grid-template-columns:1fr}
  section{padding:60px 0}
}
@media (max-width:560px){
  .steps{grid-template-columns:1fr} .trust{grid-template-columns:1fr} .foot{grid-template-columns:1fr}
  .cards.c4{grid-template-columns:1fr} .tiers{grid-template-columns:1fr} .ctaband{padding:40px 24px}
  .bar .right .btn.primary{display:none}
  .detailgrid div{grid-template-columns:1fr;gap:2px}
}