/* devtail — landing page */

:root {
  --bg: #FFFFFF;
  --bg-soft: #FAFAFA;
  --surface: #FFFFFF;
  --ink: #09090B;
  --ink-soft: #18181B;
  --ink-2: #3F3F46;
  --muted: #71717A;
  --muted-2: #A1A1AA;
  --hairline: #E4E4E7;
  --hairline-strong: #D4D4D8;

  --accent: #1F47FF;
  --accent-soft: #EEF1FF;
  --accent-ink: #1736B5;
  --accent-tint: #DEE4FF;

  --ok: #15803D;

  --dark: #09090B;
  --dark-2: #0F0F11;
  --dark-ink: #FAFAFA;
  --dark-muted: #71717A;
  --dark-hairline: #27272A;
  --dark-card: #131316;

  --font-sans: "Geist", -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
  --font-mono: "Geist Mono", ui-monospace, "SF Mono", Menlo, monospace;

  --max: 1240px;
  --gutter: clamp(20px, 4vw, 56px);
  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 14px;
}

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

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.55;
  font-feature-settings: "ss01", "ss03", "cv01", "cv11";
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: inherit; text-decoration: none; }

::selection { background: var(--accent); color: #fff; }

/* ---------- helpers ---------- */

.overline {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 18px;
}

.overline--light { color: var(--muted-2); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--ink-soft);
  padding: 6px 12px 6px 10px;
  border: 1px solid var(--hairline);
  border-radius: 999px;
  background: var(--bg);
  margin-bottom: 32px;
  box-shadow: 0 1px 0 rgba(9, 9, 11, 0.02);
}

.eyebrow__dot {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px rgba(31, 71, 255, 0.10);
}

.section-head {
  max-width: 760px;
  margin-bottom: 56px;
}

.section-title {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: clamp(36px, 4.6vw, 56px);
  line-height: 1.04;
  letter-spacing: -0.025em;
  margin: 0 0 18px;
  color: var(--ink);
}

.section-sub {
  font-size: 18px;
  color: var(--ink-2);
  max-width: 60ch;
  margin: 0;
  line-height: 1.55;
}

.hl {
  color: var(--accent);
  font-weight: 500;
}

.dot {
  display: inline-block;
  width: 7px; height: 7px;
  border-radius: 50%;
  vertical-align: 1px;
  margin-right: 6px;
}
.dot--ok { background: var(--ok); box-shadow: 0 0 0 3px rgba(21, 128, 61, 0.10); }

/* ---------- nav ---------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px) saturate(140%);
  -webkit-backdrop-filter: blur(12px) saturate(140%);
  background: rgba(255, 255, 255, 0.78);
  border-bottom: 1px solid var(--hairline);
}

.nav__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px var(--gutter);
  display: flex;
  align-items: center;
  gap: 32px;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: -0.018em;
  color: var(--ink);
}

.wordmark__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px; height: 24px;
  border-radius: 6px;
  background: var(--ink);
  color: var(--bg);
}
.wordmark__mark svg { width: 14px; height: 14px; }

.wordmark--footer .wordmark__mark { width: 22px; height: 22px; border-radius: 5px; }

.nav__links {
  display: flex;
  gap: 24px;
  margin-left: 8px;
}

.nav__links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-2);
  transition: color 160ms ease;
}
.nav__links a:hover { color: var(--ink); }

.nav__cta {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 12px;
}

.link-quiet {
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-2);
}
.link-quiet:hover { color: var(--ink); }

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-sans);
  font-size: 14.5px;
  font-weight: 500;
  letter-spacing: -0.005em;
  padding: 11px 18px;
  border-radius: 8px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 140ms ease, background 140ms ease, color 140ms ease, border-color 140ms ease, box-shadow 140ms ease;
  white-space: nowrap;
}

.btn--sm { padding: 8px 14px; font-size: 13.5px; }

.btn--primary {
  background: var(--ink);
  color: var(--bg);
  border-color: var(--ink);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.08),
    0 1px 0 rgba(9,9,11,0.06),
    0 8px 24px -12px rgba(9, 9, 11, 0.35);
}
.btn--primary:hover { transform: translateY(-1px); box-shadow: inset 0 1px 0 rgba(255,255,255,0.08), 0 1px 0 rgba(9,9,11,0.06), 0 12px 28px -12px rgba(9, 9, 11, 0.45); }

.btn--secondary {
  background: var(--bg);
  color: var(--ink);
  border-color: var(--hairline-strong);
}
.btn--secondary:hover { border-color: var(--ink); }

/* ---------- hero ---------- */

.hero {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(72px, 11vw, 128px) var(--gutter) clamp(72px, 9vw, 112px);
  position: relative;
}

.hero::after {
  /* faint gridded backdrop, never dominant */
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--hairline) 1px, transparent 1px),
    linear-gradient(to bottom, var(--hairline) 1px, transparent 1px);
  background-size: 64px 64px;
  background-position: -1px -1px;
  mask-image: radial-gradient(ellipse at 50% 0%, rgba(0,0,0,0.16) 0%, transparent 65%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 0%, rgba(0,0,0,0.16) 0%, transparent 65%);
  z-index: 0;
}

.hero__inner { position: relative; z-index: 1; max-width: 880px; }

.display {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: clamp(46px, 7.2vw, 92px);
  line-height: 1.01;
  letter-spacing: -0.038em;
  margin: 0 0 28px;
  color: var(--ink);
}

.lede {
  font-size: clamp(17px, 1.35vw, 20px);
  line-height: 1.5;
  color: var(--ink-2);
  max-width: 60ch;
  margin: 0 0 36px;
}

.cta-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.hero__meta {
  position: relative;
  z-index: 1;
  margin-top: 32px;
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0;
  color: var(--muted);
}
.hero__meta .sep { color: var(--hairline-strong); }

/* ---------- diagram ---------- */

.diagram {
  position: relative;
  z-index: 1;
  margin: clamp(48px, 6vw, 72px) 0 0;
  padding: 0;
  background: var(--bg);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow:
    0 1px 0 rgba(255,255,255,0.6) inset,
    0 1px 2px rgba(9, 9, 11, 0.04),
    0 20px 56px -28px rgba(9, 9, 11, 0.22),
    0 60px 120px -60px rgba(9, 9, 11, 0.18);
}

.diagram__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 18px;
  background: var(--bg-soft);
  border-bottom: 1px solid var(--hairline);
}

.diagram__label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--ink-soft);
}

.diagram__square {
  display: inline-block;
  width: 8px; height: 8px;
  background: var(--ink);
  border-radius: 2px;
}

.diagram__chip {
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  color: var(--ok);
  background: rgba(21, 128, 61, 0.10);
  border: 1px solid rgba(21, 128, 61, 0.22);
  padding: 3px 9px 3px 7px;
  border-radius: 999px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.diagram__chip .dot { margin-right: 4px; vertical-align: 0; }

.diagram__svg-wrap {
  padding: 16px clamp(8px, 1.6vw, 24px) 8px;
  background:
    radial-gradient(ellipse at 50% 40%, rgba(31, 71, 255, 0.045) 0%, transparent 60%),
    var(--bg);
}

.diagram__svg {
  display: block;
  width: 100%;
  height: auto;
  max-height: 460px;
}

/* SVG text styles */
.diagram__svg text { font-family: var(--font-sans); }

.diagram__svg .d-col-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.10em;
  fill: var(--muted);
  font-weight: 500;
}

.diagram__svg .d-card-name {
  font-size: 15px;
  font-weight: 500;
  fill: var(--ink);
  letter-spacing: -0.01em;
}

.diagram__svg .d-card-role {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.10em;
  fill: var(--accent);
  font-weight: 500;
}

.diagram__svg .d-card-mono {
  font-family: var(--font-mono);
  font-size: 11px;
  fill: var(--muted);
}

.diagram__svg .d-hub-name {
  font-size: 16px;
  font-weight: 600;
  fill: #FAFAFA;
  letter-spacing: -0.018em;
}

.diagram__svg .d-hub-line {
  font-size: 12.5px;
  fill: #A1A1AA;
}

.diagram__svg .d-card-kicker {
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.10em;
  fill: var(--accent);
  font-weight: 500;
}

.diagram__svg .d-card-title {
  font-size: 17px;
  font-weight: 600;
  fill: var(--ink);
  letter-spacing: -0.018em;
}

.diagram__svg .d-card-sub {
  font-size: 12.5px;
  fill: var(--ink-2);
}

.diagram__legend {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 28px;
  padding: 10px 16px 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.02em;
  color: var(--muted);
  flex-wrap: wrap;
}

.diagram__legend-dot {
  display: inline-block;
  width: 7px; height: 7px;
  background: var(--accent);
  border-radius: 50%;
  vertical-align: 1px;
  margin-right: 6px;
  box-shadow: 0 0 0 3px rgba(31, 71, 255, 0.16);
}
.diagram__legend-dot--mid { background: var(--ink); box-shadow: 0 0 0 3px rgba(9, 9, 11, 0.10); }
.diagram__legend-dot--out { background: var(--accent); box-shadow: 0 0 0 3px rgba(31, 71, 255, 0.16); }

@media (max-width: 720px) {
  .diagram__legend { gap: 14px; font-size: 10.5px; padding: 12px 14px; }
}

/* ---------- trust strip ---------- */

.trust {
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  background: var(--bg-soft);
}

.trust__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 28px var(--gutter);
  display: flex;
  align-items: center;
  gap: 32px;
  flex-wrap: wrap;
  justify-content: space-between;
}

.trust__label {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0;
  flex-shrink: 0;
}

.trust__row {
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
  font-size: 14px;
  color: var(--ink-soft);
  font-weight: 500;
  letter-spacing: -0.005em;
}

.trust__sep {
  width: 3px; height: 3px;
  background: var(--hairline-strong);
  border-radius: 50%;
}

/* ---------- thesis ---------- */

.thesis {
  background: var(--bg);
  border-bottom: 1px solid var(--hairline);
}

.thesis__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(80px, 11vw, 144px) var(--gutter);
}

.thesis__text {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: clamp(30px, 4.4vw, 52px);
  line-height: 1.08;
  letter-spacing: -0.028em;
  color: var(--ink);
  margin: 0 0 28px;
  max-width: 26ch;
}

.thesis__sub {
  font-size: 18px;
  color: var(--ink-2);
  max-width: 56ch;
  margin: 0;
}

/* ---------- how it works ---------- */

.how {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(80px, 10vw, 128px) var(--gutter);
}

.steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.step {
  position: relative;
  padding: 28px;
  background: var(--bg-soft);
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  transition: border-color 200ms ease, transform 200ms ease, box-shadow 200ms ease;
}

.step:hover {
  border-color: var(--hairline-strong);
  transform: translateY(-2px);
  box-shadow: 0 12px 28px -16px rgba(9, 9, 11, 0.14);
}

.step__top {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 28px;
}

.step__num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--muted);
}

.step__pill {
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid var(--accent-tint);
  padding: 2px 8px;
  border-radius: 999px;
  text-transform: lowercase;
  letter-spacing: 0.02em;
}

.step__title {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 22px;
  line-height: 1.22;
  letter-spacing: -0.018em;
  margin: 0 0 12px;
  color: var(--ink);
}

.step__body {
  font-size: 15px;
  line-height: 1.55;
  color: var(--ink-2);
  margin: 0 0 22px;
}

.step__list {
  list-style: none;
  margin: 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--hairline);
  display: grid;
  gap: 8px;
}

.step__list li {
  position: relative;
  padding-left: 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
  letter-spacing: 0;
}

.step__list li::before {
  content: "";
  position: absolute;
  left: 0; top: 8px;
  width: 8px; height: 1px;
  background: var(--muted-2);
}

/* ---------- who ---------- */

.who {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(80px, 10vw, 128px) var(--gutter);
  border-top: 1px solid var(--hairline);
}

.who-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.who-card {
  padding: 26px;
  background: var(--bg);
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  gap: 14px;
  transition: border-color 200ms ease, background 200ms ease;
}

.who-card:hover {
  border-color: var(--hairline-strong);
  background: var(--bg-soft);
}

.who-card__tag {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  align-self: flex-start;
  padding: 4px 8px;
  background: var(--accent-soft);
  border: 1px solid var(--accent-tint);
  border-radius: 6px;
}

.who-card__body {
  font-size: 15.5px;
  line-height: 1.5;
  color: var(--ink-soft);
  margin: 0;
  letter-spacing: -0.005em;
}

.who-card--more {
  background: linear-gradient(180deg, var(--bg) 0%, var(--accent-soft) 200%);
  border-style: dashed;
}

.who-card--more .who-card__tag {
  color: var(--ink);
  background: var(--bg);
  border-color: var(--hairline-strong);
}

/* ---------- privacy (dark panel) ---------- */

.privacy {
  background: var(--dark);
  color: var(--dark-ink);
  position: relative;
  overflow: hidden;
}

.privacy::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--dark-hairline) 1px, transparent 1px),
    linear-gradient(to bottom, var(--dark-hairline) 1px, transparent 1px);
  background-size: 64px 64px;
  background-position: -1px -1px;
  mask-image: radial-gradient(ellipse at 50% 0%, rgba(0,0,0,0.5) 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 0%, rgba(0,0,0,0.5) 0%, transparent 70%);
  pointer-events: none;
  opacity: 0.55;
}

.privacy__inner {
  position: relative;
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(80px, 10vw, 128px) var(--gutter);
}

.privacy__title {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: clamp(36px, 4.6vw, 56px);
  line-height: 1.04;
  letter-spacing: -0.028em;
  color: var(--dark-ink);
  margin: 0 0 18px;
  max-width: 22ch;
}

.privacy__body {
  font-size: 18px;
  line-height: 1.55;
  color: #C7C7CC;
  max-width: 60ch;
  margin: 0 0 48px;
}

.privacy__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.privacy__card {
  padding: 22px;
  background: var(--dark-card);
  border: 1px solid var(--dark-hairline);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.privacy__card h3 {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: 15.5px;
  letter-spacing: -0.015em;
  margin: 4px 0 2px;
  color: var(--dark-ink);
}

.privacy__card p {
  font-size: 13.5px;
  line-height: 1.5;
  color: #9F9FA8;
  margin: 0;
}

.privacy__icon {
  width: 26px;
  height: 26px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  color: var(--accent);
  background: rgba(31, 71, 255, 0.12);
  border: 1px solid rgba(31, 71, 255, 0.28);
  border-radius: 6px;
  margin-bottom: 8px;
}

/* ---------- cta ---------- */

.cta {
  background:
    radial-gradient(ellipse at 50% 0%, var(--accent-soft) 0%, var(--bg) 65%),
    var(--bg);
  border-top: 1px solid var(--hairline);
}

.cta__inner {
  max-width: 760px;
  margin: 0 auto;
  padding: clamp(80px, 10vw, 128px) var(--gutter);
  text-align: center;
}

.cta__overline { color: var(--accent); }

.cta__title {
  font-family: var(--font-sans);
  font-weight: 500;
  font-size: clamp(38px, 5.4vw, 64px);
  line-height: 1.04;
  letter-spacing: -0.03em;
  margin: 0 0 20px;
  color: var(--ink);
  max-width: 22ch;
  margin-left: auto;
  margin-right: auto;
}

.cta__sub {
  font-size: 18px;
  color: var(--ink-2);
  margin: 0 auto 36px;
  max-width: 58ch;
}

.cta__form {
  display: flex;
  gap: 10px;
  max-width: 480px;
  margin: 0 auto;
  align-items: stretch;
}

.cta__form input {
  flex: 1;
  font-family: var(--font-sans);
  font-size: 15px;
  color: var(--ink);
  padding: 12px 16px;
  background: var(--bg);
  border: 1px solid var(--hairline-strong);
  border-radius: 8px;
  outline: none;
  transition: border-color 140ms ease, box-shadow 140ms ease;
}
.cta__form input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(31, 71, 255, 0.14);
}
.cta__form input::placeholder { color: var(--muted-2); }

.cta__note {
  font-size: 13.5px;
  color: var(--muted);
  margin: 22px 0 0;
}
.cta__note a { color: var(--accent); }
.cta__note a:hover { text-decoration: underline; }

/* ---------- footer ---------- */

.footer {
  background: var(--bg);
  border-top: 1px solid var(--hairline);
}

.footer__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 56px var(--gutter) 32px;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 32px;
}

.footer__col {
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 14px;
  color: var(--ink-2);
}

.footer__col a {
  font-size: 14px;
  color: var(--muted);
  transition: color 160ms ease;
}
.footer__col a:hover { color: var(--ink); }

.footer__col--brand { gap: 14px; }

.footer__heading {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink);
  margin: 0 0 4px;
}

.footer__tag {
  font-size: 14px;
  color: var(--muted);
  margin: 0;
  max-width: 32ch;
  line-height: 1.5;
}

.footer__bar {
  max-width: var(--max);
  margin: 0 auto;
  padding: 20px var(--gutter);
  border-top: 1px solid var(--hairline);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 12.5px;
  color: var(--muted);
}

.footer__mono {
  font-family: var(--font-mono);
  font-size: 11.5px;
}

/* ---------- responsive ---------- */

@media (max-width: 980px) {
  .steps { grid-template-columns: 1fr 1fr; }
  .who-grid { grid-template-columns: 1fr 1fr; }
  .privacy__grid { grid-template-columns: 1fr 1fr; }
  .footer__inner { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  .nav__links { display: none; }
  .steps { grid-template-columns: 1fr; }
  .who-grid { grid-template-columns: 1fr; }
  .privacy__grid { grid-template-columns: 1fr; }
  .footer__inner { grid-template-columns: 1fr 1fr; }
  .cta__form { flex-direction: column; }
  .trust__inner { gap: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  .btn, .step, .who-card { transition: none; }
  .diagram__svg animateMotion { display: none; }
  html { scroll-behavior: auto; }
}