/* The public home page at /. Uses the application's tokens (tokens.css) and fonts (fonts.css).
   The one bold element is the specimen-tube rack; everything around it stays quiet. */

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

/* The home page is always light: its subject is white report paper, and a dark room around
   white sheets is glaring. The palette is soft and low-contrast, with a sage-gray tint for the
   sections that hold report pages so the paper sits gently on it. */
:root,
:root[data-theme] {
  color-scheme: light;
  --ink: #1d2731;
  --body: #3a4652;
  --muted: #5b6672;
  --canvas: #f6f8f7;
  --tint: #ebf0ee;
  --surface: #ffffff;
  --line: #dde4e1;
  --brand: #0f6a68;
  --rack: #dde5e2;
  --rack-edge: #c8d3cf;
  --paper-edge: rgb(29 39 49 / 8%);
  --paper-shadow: 0 0 0 1px var(--paper-edge), 0 2px 4px rgb(29 39 49 / 4%), 0 18px 40px -22px rgb(29 39 49 / 28%);
}

html {
  scroll-behavior: smooth;
  scrollbar-color: var(--rack-edge) var(--canvas);
  -webkit-text-size-adjust: 100%;
}

::selection {
  background: #cbe6e3;
  color: var(--ink);
}

body {
  margin: 0;
  background: var(--canvas);
  color: var(--body);
  font: 400 var(--lm-font-size-base) / 1.6 var(--lm-font-family-prose);
}

h1,
h2,
h3 {
  margin: 0;
  color: var(--ink);
  font-family: var(--lm-font-family-display);
  font-weight: 600;
  line-height: 1.15;
  text-wrap: balance;
}

p,
ul,
ol,
dl,
dd,
figure {
  margin: 0;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: var(--lm-color-fg-accent);
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--lm-color-fg-accent-hover);
}

:focus-visible {
  outline: var(--lm-focus-width) solid var(--lm-color-focus-ring);
  outline-offset: var(--lm-focus-offset);
}

section[id] {
  scroll-margin-top: 4.5rem;
}

.wrap {
  width: min(74rem, 100% - 2.5rem);
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  left: 1rem;
  top: 0;
  z-index: 10;
  transform: translateY(-150%);
  padding: 0.5rem 1rem;
  border-radius: var(--lm-radius-sm);
  background: var(--lm-color-bg-raised);
  box-shadow: var(--lm-shadow-card);
}

.skip-link:focus {
  transform: translateY(0.5rem);
}

/* ---------- Buttons and links ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.75rem;
  padding: 0 1.375rem;
  border-radius: var(--lm-radius-control);
  font: 600 var(--lm-font-size-md) / 1 var(--lm-font-family-ui);
  text-decoration: none;
  white-space: nowrap;
  transition: background-color var(--lm-motion-duration-base), color var(--lm-motion-duration-base);
}

.btn-small {
  min-height: 2.375rem;
  padding: 0 1.125rem;
  font-size: var(--lm-font-size-sm);
}

.btn-large {
  min-height: 3.25rem;
  padding: 0 1.75rem;
  font-size: var(--lm-font-size-base);
}

.btn-primary {
  background: var(--lm-color-bg-accent);
  color: var(--lm-color-fg-on-accent);
}

.btn-primary:hover {
  background: var(--lm-color-bg-accent-hover);
  color: var(--lm-color-fg-on-accent);
}

.btn-secondary {
  background: var(--surface);
  color: var(--ink);
  box-shadow: inset 0 0 0 1px var(--lm-color-border-strong);
}

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

.btn-quiet {
  color: var(--ink);
  box-shadow: inset 0 0 0 1px var(--line);
}

.btn-quiet:hover {
  background: var(--lm-color-bg-hover);
  color: var(--ink);
}

.text-link {
  font-weight: 600;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 5;
  background: color-mix(in srgb, var(--canvas) 90%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  min-height: 4rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  color: var(--ink);
  font: 600 var(--lm-font-size-md) / 1 var(--lm-font-family-ui);
  text-decoration: none;
}

.brand:hover {
  color: var(--ink);
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 2rem;
  height: 2rem;
  border-radius: 9px;
  background: var(--brand);
}

.brand-mark svg {
  width: 1.375rem;
  height: 1.375rem;
  fill: #fff;
}

.brand-mark .trend {
  fill: none;
  stroke: rgb(255 255 255 / 45%);
  stroke-width: 1.2;
  stroke-dasharray: 0.4 2;
  stroke-linecap: round;
}

.site-nav {
  display: flex;
  gap: 0.25rem;
  margin-left: auto;
}

.site-nav a {
  padding: 0.5rem 0.75rem;
  border-radius: var(--lm-radius-control);
  color: var(--body);
  font: 500 var(--lm-font-size-sm) / 1 var(--lm-font-family-ui);
  text-decoration: none;
}

.site-nav a:hover {
  background: var(--lm-color-bg-hover);
  color: var(--ink);
}

/* ---------- Hero: real report sheets ---------- */

.hero {
  overflow: hidden;
  padding: 4.5rem 0 5rem;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 3rem;
  align-items: center;
}

.hero h1 {
  max-width: 13ch;
  font-size: clamp(2.25rem, 1.2rem + 3.6vw, 4rem);
  letter-spacing: -0.03em;
  line-height: 1.04;
}

.lede {
  max-width: 34rem;
  margin: 1.5rem 0 2rem;
  font-size: var(--lm-font-size-lg);
}

.note {
  margin-top: 1.25rem;
  color: var(--muted);
  font-size: var(--lm-font-size-sm);
}

.hero-sheets {
  position: relative;
  height: 34rem;
}

.sheet {
  position: absolute;
  background: #fff;
  border-radius: 6px;
  box-shadow: var(--paper-shadow);
  padding: 1.25rem;
}

.sheet-back {
  top: 0;
  right: -2rem;
  width: 78%;
  transform: rotate(4deg);
  opacity: 0.95;
}

.sheet-front {
  top: 2.5rem;
  left: 0;
  width: 72%;
  transform: rotate(-2.5deg);
}

/* ---------- Before and after ---------- */

.swap {
  padding: 5.5rem 0;
}

.swap h2 {
  max-width: 22ch;
  font-size: clamp(1.75rem, 1.2rem + 1.8vw, 2.625rem);
  letter-spacing: -0.02em;
}

.ledger {
  margin-top: 2.5rem;
}

.ledger-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 3rem;
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--line);
}

.ledger-labels {
  padding: 0.875rem 0;
  color: var(--muted);
  font: 600 var(--lm-font-size-sm) / 1.3 var(--lm-font-family-ui);
}

.ledger-row.ledger-labels {
  border-bottom: 2px solid var(--ink);
}

.ledger-labels p {
  padding-left: 2rem;
}

.ledger-labels p:last-child {
  color: var(--lm-color-fg-accent);
}

.ledger-before {
  position: relative;
  padding-left: 2rem;
  color: var(--muted);
  font-size: var(--lm-font-size-lg);
}

/* A small cross for the old way, a check for the new one. */
.ledger-before::before,
.ledger-before::after {
  content: "";
  position: absolute;
  left: 0.2rem;
  top: 0.8em;
  width: 0.9rem;
  height: 2px;
  border-radius: 1px;
  background: #c9716b;
  transform: rotate(45deg);
}

.ledger-before::after {
  transform: rotate(-45deg);
}

.ledger-after {
  position: relative;
  padding-left: 2rem;
  color: var(--ink);
  font-size: var(--lm-font-size-lg);
  font-weight: 500;
}

.ledger-after::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35em;
  width: 1.1rem;
  height: 0.6rem;
  border-left: 3px solid var(--lm-color-status-ok-fg);
  border-bottom: 3px solid var(--lm-color-status-ok-fg);
  transform: rotate(-45deg);
}

/* ---------- Tube rack ---------- */

.rack-section {
  padding: 5rem 0 5.5rem;
  background: var(--tint);
}

.section-intro {
  max-width: 40rem;
  margin-bottom: 2.75rem;
}

.section-intro h2,
.trust h2,
.signup h2 {
  font-size: clamp(1.75rem, 1.2rem + 1.8vw, 2.625rem);
  letter-spacing: -0.02em;
}

.section-intro p {
  margin-top: 0.75rem;
  color: var(--muted);
  font-size: var(--lm-font-size-lg);
}

.rack {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.5rem;
  margin-top: 4.5rem;
  padding: 0 1rem;
}

/* The rack's front rail: tubes stand in it, and the chosen one lifts out. */
.rack::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 8.75rem;
  height: 3.25rem;
  border-radius: 10px;
  background: var(--rack);
  box-shadow: inset 0 -3px 0 var(--rack-edge);
  z-index: 3;
  pointer-events: none;
}

.tube {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
  padding: 0.75rem 0 0;
  border: 0;
  background: none;
  color: var(--muted);
  font: 500 var(--lm-font-size-sm) / 1.25 var(--lm-font-family-ui);
  text-align: center;
  cursor: pointer;
}

.tube-body {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: transform 0.35s cubic-bezier(0.2, 0.8, 0.2, 1.2);
}

.tube-cap {
  width: 3rem;
  height: 1.625rem;
  border-radius: 7px 7px 3px 3px;
  background:
    linear-gradient(90deg, rgb(255 255 255 / 0%) 20%, rgb(255 255 255 / 35%) 35%, rgb(255 255 255 / 0%) 50%),
    var(--cap);
  box-shadow: inset 0 -3px 0 rgb(0 0 0 / 15%);
}

.tube-glass {
  position: relative;
  width: 2.375rem;
  height: 9rem;
  overflow: hidden;
  border: 2px solid light-dark(rgb(23 32 42 / 22%), rgb(232 237 240 / 30%));
  border-top: 0;
  border-radius: 0 0 1.2rem 1.2rem;
  background: light-dark(rgb(255 255 255 / 70%), rgb(255 255 255 / 6%));
}

.tube-fill {
  position: absolute;
  inset: auto 0 0;
  height: 62%;
  background: linear-gradient(90deg, rgb(255 255 255 / 0%) 55%, rgb(255 255 255 / 30%) 70%, rgb(255 255 255 / 0%) 85%), var(--fill);
}

/* A printed label strip, as on a real tube. */
.tube-glass::after {
  content: "";
  position: absolute;
  inset: 0.875rem 48% 1.75rem 0.25rem;
  border-radius: 2px;
  background: repeating-linear-gradient(0deg, rgb(23 32 42 / 16%) 0 1px, transparent 1px 5px), #fff;
  opacity: 0.9;
  z-index: 1;
}

.tube-name {
  position: relative;
  z-index: 4;
  max-width: min(13rem, 100%);
  padding: 0.25rem 0.5rem;
  border-radius: var(--lm-radius-sm);
}

.tube:hover .tube-body {
  transform: translateY(-0.375rem);
}

.tube:hover {
  color: var(--ink);
}

.tube[aria-selected="true"] .tube-body {
  transform: translateY(-3.25rem) rotate(-5deg);
}

.tube[aria-selected="true"] .tube-name {
  background: var(--ink);
  color: var(--canvas);
  font-weight: 600;
}

.tube:focus-visible {
  outline: none;
}

.tube:focus-visible .tube-name {
  outline: var(--lm-focus-width) solid var(--lm-color-focus-ring);
  outline-offset: 2px;
}

.panels {
  margin-top: 3rem;
}

.panel {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
  gap: 3.5rem;
  align-items: start;
}

/* Without JavaScript every panel shows, one after another. */
.panel + .panel {
  margin-top: 4rem;
}

.js .panel + .panel {
  margin-top: 0;
}

.panel[hidden] {
  display: none;
}

/* The study's details, set out like a specimen label. */
.label-card {
  position: sticky;
  top: 6rem;
  overflow: hidden;
  border-radius: 10px;
  background: var(--surface);
  box-shadow: var(--paper-shadow);
}

.label-head {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.5rem;
  border-bottom: 2px solid var(--ink);
}

.label-dot {
  flex: none;
  width: 1rem;
  height: 1rem;
  border-radius: 4px;
  background: var(--active-cap, var(--lm-color-border-accent));
}

.label-head h3 {
  font-size: var(--lm-font-size-2xl);
  letter-spacing: -0.01em;
}

.label-fields > div {
  display: grid;
  grid-template-columns: 8.5rem minmax(0, 1fr);
  gap: 1rem;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--line);
}

.label-fields dt {
  color: var(--muted);
  font-size: var(--lm-font-size-sm);
  line-height: 1.6;
}

.label-fields dd {
  color: var(--ink);
}

.label-fields > div:first-child dd {
  font-size: var(--lm-font-size-lg);
  font-weight: 600;
  line-height: 1.35;
}

.label-foot {
  padding: 1rem 1.5rem 1.25rem;
}

.paper {
  padding: clamp(1rem, 2.5vw, 2rem);
  border-radius: 6px;
  background: #fff;
  box-shadow: var(--paper-shadow);
}

.more {
  margin-top: 3.5rem;
  color: var(--muted);
}

/* ---------- How a study goes: real screens in order ---------- */

.how {
  padding: 5.5rem 0;
}

.film {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 3rem 2.5rem;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.film li {
  counter-increment: step;
}

.film figure {
  aspect-ratio: 16 / 10;
  overflow: hidden;
  border-radius: var(--lm-radius-md);
  background: var(--surface);
  box-shadow: var(--paper-shadow);
}

.film img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: left top;
}

.film h3 {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  margin: 1.25rem 0 0.5rem;
  font-size: var(--lm-font-size-lg);
}

.film h3::before {
  content: counter(step);
  color: var(--lm-color-fg-accent);
  font-size: var(--lm-font-size-2xl);
  font-variant-numeric: tabular-nums;
}

.film p {
  max-width: 34rem;
}

/* ---------- Trust ---------- */

.trust {
  padding: 5.5rem 0;
  background: var(--tint);
}

.trust-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 4rem;
  align-items: center;
}

.paper-crop {
  max-height: 36rem;
  overflow: hidden;
  transform: rotate(-1.5deg);
  -webkit-mask-image: linear-gradient(#000 80%, transparent);
  mask-image: linear-gradient(#000 80%, transparent);
}

.trust-copy > p {
  margin-top: 1rem;
  max-width: 34rem;
}

.promises {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.5rem 2rem;
  margin: 2rem 0;
}

.promises dt {
  color: var(--ink);
  font-weight: 600;
}

.promises dd {
  margin-top: 0.25rem;
  font-size: var(--lm-font-size-md);
}

.fine {
  color: var(--muted);
  font-size: var(--lm-font-size-sm);
}

/* ---------- Sign up ---------- */

.signup {
  padding: 5rem 0;
}

.signup-inner {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: 3rem;
  align-items: center;
  padding: clamp(2rem, 4vw, 3.5rem);
  border-radius: var(--lm-radius-lg);
  background: var(--brand);
  color: #e6f2f1;
}

.signup h2 {
  color: #fff;
}

.signup p {
  margin-top: 1rem;
  max-width: 36rem;
}

.signup .actions {
  justify-content: flex-end;
}

.signup .btn-primary {
  background: #fff;
  color: #0b4f4d;
}

.signup .btn-primary:hover {
  background: #e1f3ec;
  color: #0b4f4d;
}

.signup .btn-secondary {
  background: transparent;
  color: #fff;
  box-shadow: inset 0 0 0 1px rgb(255 255 255 / 55%);
}

.signup .btn-secondary:hover {
  background: rgb(255 255 255 / 10%);
}

/* ---------- Footer ---------- */

.site-footer {
  padding: 0 0 2.5rem;
  color: var(--muted);
  font-size: var(--lm-font-size-sm);
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
}

.site-footer a {
  color: var(--body);
}

/* ---------- Narrower screens ---------- */

@media (max-width: 62rem) {
  .ledger-row {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.75rem;
  }

  .ledger-labels {
    display: none;
  }

  .hero-inner,
  .panel,
  .trust-inner,
  .signup-inner {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero-sheets {
    height: 26rem;
    max-width: 34rem;
  }

  .label-card {
    position: static;
  }

  .panel {
    gap: 2rem;
  }

  .signup .actions {
    justify-content: flex-start;
  }

  /* The rack becomes a row of tubes you can swipe through. */
  .rack {
    display: flex;
    gap: 0.25rem;
    margin-inline: -1.25rem;
    margin-top: 1rem;
    padding: 3.75rem 1.25rem 0.5rem;
    overflow-x: auto;
    overscroll-behavior-x: contain;
    scroll-padding-inline: 1.25rem;
    scroll-snap-type: x mandatory;
    scrollbar-width: none;
  }

  .rack::before {
    top: 12.5rem;
    left: 1.25rem;
    right: auto;
    width: calc(4 * 7.25rem);
  }

  .tube {
    flex: 0 0 7rem;
    scroll-snap-align: start;
  }
}

@media (max-width: 44rem) {
  .site-nav {
    display: none;
  }

  .header-inner {
    justify-content: space-between;
  }

  .hero {
    padding: 2.5rem 0 3rem;
  }

  .hero-sheets {
    height: 20rem;
  }

  .sheet {
    padding: 0.625rem;
  }

  .rack-section,
  .how,
  .trust {
    padding: 3.5rem 0;
  }

  .film,
  .promises {
    grid-template-columns: minmax(0, 1fr);
  }

  .actions .btn {
    flex: 1 1 100%;
  }

  .label-fields > div {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.375rem;
  }

  .paper-crop {
    transform: none;
    max-height: 26rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .tube-body,
  .btn {
    transition: none;
  }
}

/* Calculation evidence and the expanded study list. */
.evidence { padding: 2.5rem 0 4rem; }
.evidence-inner { display: grid; grid-template-columns: 1fr 2fr; gap: 3rem; align-items: start; padding-top: 2rem; border-top: 2px solid var(--brand); }
.evidence p { max-width: 44rem; margin-bottom: .75rem; }
.all-studies { margin-top: 3rem; border-block: 1px solid var(--rack-edge); }
.all-studies summary { padding: 1.25rem 0; cursor: pointer; color: var(--ink); font-weight: 600; }
.study-index { display: grid; grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr)); gap: 2rem; list-style: none; padding: .5rem 0 2rem; }
.study-index strong, .study-index a { display: block; }
.study-index strong { color: var(--ink); margin-bottom: .5rem; }
.study-index a { padding-block: .2rem; }
.label-foot { display: flex; flex-wrap: wrap; gap: .75rem 1.5rem; }
@media (max-width: 62rem) { .evidence-inner { grid-template-columns: 1fr; gap: 1rem; } }