/* ==========================================================================
   Zettar Tech: base.css
   Tokens sampled from the primary logo lockup, reset, typography, layout.
   ========================================================================== */

:root {
  /* --- Sampled from the logo -------------------------------------------- */
  --zt-ink:     #14181B;   /* the mark and "ZETTAR" */
  --zt-teal:    #3E7E92;   /* lower bracket and the logo tagline */
  --zt-stone:   #5A5D5A;   /* "TECH" */
  --zt-plate:   #E6E7E5;   /* the logo plate */

  /* --- Derived ----------------------------------------------------------- */
  --zt-ink-soft:   #2E3438;
  --zt-teal-deep:  #2C5F71;
  --zt-teal-tint:  #EAF1F3;
  --zt-muted:      #6A7175;
  --zt-faint:      #8D9294;
  --zt-line:       #D9DBD8;
  --zt-line-soft:  #EAEBE8;
  --zt-paper:      #FFFFFF;
  --zt-paper-2:    #F5F6F4;

  /* The dark band keeps its own tokens so it never inverts with the theme. */
  --zt-band-bg:     #14181B;
  --zt-band-fg:     #B4BABC;
  --zt-band-strong: #F2F3F1;
  --zt-band-line:   #3A4245;
  --zt-band-accent: #7FBACD;

  /* --- Roles -------------------------------------------------------------- */
  --zt-fg:         var(--zt-ink);
  --zt-fg-2:       var(--zt-ink-soft);
  --zt-bg:         var(--zt-paper);
  --zt-bg-2:       var(--zt-paper-2);
  --zt-bg-3:       var(--zt-plate);
  --zt-accent:     var(--zt-teal);
  --zt-accent-ink: #FFFFFF;

  /* --- Type ---------------------------------------------------------------- */
  --zt-font-display: 'Jost', 'Century Gothic', Futura, system-ui, sans-serif;
  --zt-font-body:    'IBM Plex Sans', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --zt-font-mono:    'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --zt-step-0: 1rem;
  --zt-step-1: 1.16rem;
  --zt-step-2: clamp(1.3rem, 1.14rem + 0.6vw, 1.55rem);
  --zt-step-3: clamp(1.6rem, 1.32rem + 1.1vw, 2.15rem);
  --zt-step-4: clamp(2.05rem, 1.6rem + 1.9vw, 3.05rem);
  --zt-step-5: clamp(2.5rem, 1.75rem + 3.1vw, 4.1rem);

  /* --- Space --------------------------------------------------------------- */
  --zt-shell:  1240px;
  --zt-narrow: 720px;
  --zt-gutter: clamp(1.15rem, 0.6rem + 2.2vw, 2.75rem);
  --zt-band:   clamp(4rem, 2.8rem + 5.2vw, 7rem);

  --zt-r: 3px;
  --zt-ease: cubic-bezier(.22,.61,.36,1);
  --zt-head-h: 74px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --zt-fg:         #E6E7E5;
    --zt-fg-2:       #C2C6C6;
    --zt-muted:      #969C9E;
    --zt-faint:      #737A7D;
    --zt-bg:         #101315;
    --zt-bg-2:       #171B1E;
    --zt-bg-3:       #1D2225;
    --zt-line:       #2A3033;
    --zt-line-soft:  #21262A;
    --zt-accent:     #6BAFC4;
    --zt-accent-ink: #0C1013;
    --zt-teal-tint:  #18262B;
    --zt-teal-deep:  #8FC7D8;
    --zt-band-bg:     #1A2023;
    --zt-band-fg:     #AAB1B4;
    --zt-band-strong: #F2F3F1;
    --zt-band-line:   #394145;
    --zt-band-accent: #8AC4D6;
  }
}

:root[data-theme="dark"] {
  --zt-fg:         #E6E7E5;
  --zt-fg-2:       #C2C6C6;
  --zt-muted:      #969C9E;
  --zt-faint:      #737A7D;
  --zt-bg:         #101315;
  --zt-bg-2:       #171B1E;
  --zt-bg-3:       #1D2225;
  --zt-line:       #2A3033;
  --zt-line-soft:  #21262A;
  --zt-accent:     #6BAFC4;
  --zt-accent-ink: #0C1013;
  --zt-teal-tint:  #18262B;
  --zt-teal-deep:  #8FC7D8;
  --zt-band-bg:     #1A2023;
  --zt-band-fg:     #AAB1B4;
  --zt-band-strong: #F2F3F1;
  --zt-band-line:   #394145;
  --zt-band-accent: #8AC4D6;
}

/* --- Reset ---------------------------------------------------------------- */

*, *::before, *::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--zt-head-h) + 20px);
}

body {
  margin: 0;
  background: var(--zt-bg);
  color: var(--zt-fg-2);
  font-family: var(--zt-font-body);
  font-size: var(--zt-step-0);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img, svg, video, canvas, iframe { display: block; max-width: 100%; }
img, video { height: auto; }

h1, h2, h3, h4, h5, h6 {
  font-family: var(--zt-font-display);
  color: var(--zt-fg);
  font-weight: 500;
  line-height: 1.08;
  letter-spacing: -0.015em;
  margin: 0 0 .55em;
  text-wrap: balance;
}
h1 { font-size: var(--zt-step-5); }
h2 { font-size: var(--zt-step-4); }
h3 { font-size: var(--zt-step-2); }
h4 { font-size: var(--zt-step-1); }
h5, h6 { font-size: var(--zt-step-0); letter-spacing: .04em; text-transform: uppercase; }

p { margin: 0 0 1.1em; }
p:last-child { margin-bottom: 0; }

a { color: var(--zt-accent); text-decoration: none; transition: color .15s var(--zt-ease); }
a:hover { color: var(--zt-teal-deep); }

ul, ol { margin: 0 0 1.1em; padding-left: 1.2em; }
li { margin-bottom: .38em; }

blockquote {
  margin: 2rem 0;
  padding: .4rem 0 .4rem 1.5rem;
  border-left: 2px solid var(--zt-accent);
  font-family: var(--zt-font-display);
  font-size: var(--zt-step-2);
  font-weight: 400;
  color: var(--zt-fg);
  line-height: 1.45;
}

code, kbd, pre { font-family: var(--zt-font-mono); font-size: .89em; }
code {
  background: var(--zt-bg-2);
  border: 1px solid var(--zt-line);
  border-radius: var(--zt-r);
  padding: .1em .38em;
}
pre {
  background: var(--zt-band-bg);
  color: var(--zt-band-strong);
  padding: 1.2rem 1.35rem;
  border-radius: var(--zt-r);
  overflow-x: auto;
}
pre code { background: none; border: 0; padding: 0; color: inherit; }

hr { border: 0; border-top: 1px solid var(--zt-line); margin: 2.5rem 0; }

table { width: 100%; border-collapse: collapse; margin-bottom: 1.5rem; font-size: .94rem; }
th, td { text-align: left; padding: .78rem 1rem; border-bottom: 1px solid var(--zt-line); }
th { font-family: var(--zt-font-display); font-weight: 500; color: var(--zt-fg); }

::selection { background: rgba(62,126,146,.2); color: var(--zt-fg); }
:focus-visible { outline: 2px solid var(--zt-accent); outline-offset: 3px; }

/* --- Layout --------------------------------------------------------------- */

.zt-shell {
  width: 100%;
  max-width: var(--zt-shell);
  margin-inline: auto;
  padding-inline: var(--zt-gutter);
}
.zt-narrow { max-width: var(--zt-narrow); margin-inline: auto; }

.zt-band { padding-block: var(--zt-band); position: relative; }
.zt-band--tight { padding-block: calc(var(--zt-band) * .6); }
.zt-band--2 { background: var(--zt-bg-2); }
.zt-band--3 { background: var(--zt-bg-3); }

.zt-band--ink { background: var(--zt-band-bg); color: var(--zt-band-fg); }
.zt-band--ink h1,
.zt-band--ink h2,
.zt-band--ink h3,
.zt-band--ink h4,
.zt-band--ink strong { color: var(--zt-band-strong); }
.zt-band--ink p { color: var(--zt-band-fg); }

.zt-grid { display: grid; gap: clamp(1rem, .5rem + 1.5vw, 1.6rem); }
.zt-grid--2 { grid-template-columns: repeat(2, minmax(0,1fr)); }
.zt-grid--3 { grid-template-columns: repeat(3, minmax(0,1fr)); }
@media (max-width: 900px) { .zt-grid--3 { grid-template-columns: repeat(2, minmax(0,1fr)); } }
@media (max-width: 620px) { .zt-grid--2, .zt-grid--3 { grid-template-columns: minmax(0,1fr); } }

/* --- Micro label ---------------------------------------------------------- */

.zt-label {
  display: block;
  font-family: var(--zt-font-mono);
  font-size: .705rem;
  font-weight: 500;
  letter-spacing: .19em;
  text-transform: uppercase;
  color: var(--zt-accent);
  margin-bottom: 1.15rem;
}
.zt-band--ink .zt-label { color: var(--zt-band-accent); }

/* --- Section heads -------------------------------------------------------- */

.zt-head { max-width: 62ch; margin-bottom: clamp(2.2rem, 1.5rem + 2vw, 3.4rem); }
.zt-head p { color: var(--zt-muted); font-size: var(--zt-step-1); max-width: 62ch; }
.zt-head--row {
  max-width: none;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 2rem;
}
.zt-head--row > div { max-width: 62ch; }
@media (max-width: 760px) { .zt-head--row { flex-direction: column; align-items: flex-start; } }

/* --- Bracket motif -------------------------------------------------------- */
/* Echoes the two interlocking brackets in the mark. */

.zt-brk { position: relative; }
.zt-brk::before,
.zt-brk::after {
  content: '';
  position: absolute;
  width: 15px;
  height: 15px;
  pointer-events: none;
  transition: width .3s var(--zt-ease), height .3s var(--zt-ease);
}
.zt-brk::before {
  top: -1px; left: -1px;
  border-top: 2px solid var(--zt-fg);
  border-left: 2px solid var(--zt-fg);
}
.zt-brk::after {
  bottom: -1px; right: -1px;
  border-bottom: 2px solid var(--zt-accent);
  border-right: 2px solid var(--zt-accent);
}
.zt-brk:hover::before,
.zt-brk:hover::after { width: 26px; height: 26px; }

/* --- Utilities ------------------------------------------------------------ */

.zt-teal { color: var(--zt-accent); font-weight: inherit; font-style: normal; }
.zt-muted { color: var(--zt-muted); }
.zt-lead { font-size: var(--zt-step-1); color: var(--zt-muted); }
.zt-center { text-align: center; }
.zt-mt { margin-top: 1.9rem; }

.zt-sr {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.zt-skip {
  position: absolute;
  left: 1rem; top: -100px;
  z-index: 999;
  background: var(--zt-fg);
  color: var(--zt-bg);
  padding: .7rem 1.1rem;
  border-radius: var(--zt-r);
  transition: top .2s var(--zt-ease);
}
.zt-skip:focus { top: 1rem; color: var(--zt-bg); }

/* --- Reveal --------------------------------------------------------------- */

.zt-rv {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .6s var(--zt-ease), transform .6s var(--zt-ease);
}
.zt-rv.is-in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .zt-rv { opacity: 1; transform: none; transition: none; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
}