:root {
  --ink: #162033;
  --muted: #5f6b7c;
  --line: #dbe3ea;
  --panel: #ffffff;
  --soft: #f4f7fa;
  --blue: #1f6feb;
  --blue-dark: #1558bd;
  --teal: #0f8f8c;
  --green: #17845b;
  --amber: #c27a12;
  --navy: #0f2238;
  --shadow: 0 18px 42px rgba(22, 32, 51, 0.12);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--soft);
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

img,
svg {
  max-width: 100%;
  display: block;
}

a {
  color: var(--blue);
  text-decoration: none;
}

a:hover {
  color: var(--blue-dark);
}

button,
input {
  font: inherit;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -48px;
  z-index: 1000;
  padding: 10px 14px;
  color: #fff;
  background: var(--navy);
  border-radius: 6px;
}

.skip-link:focus {
  top: 16px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(10px);
}

.nav-wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 24px;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  font-weight: 800;
  letter-spacing: 0;
  white-space: nowrap;
}

.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  color: #fff;
  background: var(--blue);
  box-shadow: inset 0 -5px 0 rgba(0, 0, 0, 0.14);
}

.brand small {
  display: block;
  color: var(--muted);
  font-size: 12px;
  font-weight: 600;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 5px auto;
  background: currentColor;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.site-nav a {
  padding: 10px 12px;
  color: #354258;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 700;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: var(--blue);
  background: #eaf2ff;
}

.nav-cta {
  color: #fff !important;
  background: var(--blue) !important;
}

.nav-cta:hover {
  background: var(--blue-dark) !important;
}

.hero {
  min-height: calc(100vh - 72px);
  max-height: 820px;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  background-color: #eef4f8;
  background-image: url("../img/memtest86-ui.svg");
  background-repeat: no-repeat;
  background-size: min(58vw, 760px) auto;
  background-position: right 7vw center;
  border-bottom: 1px solid var(--line);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 58%;
  background: rgba(244, 247, 250, 0.92);
}

.hero-inner {
  position: relative;
  width: 100%;
  max-width: var(--max);
  margin: 0 auto;
  padding: 72px 24px 96px;
}

.hero-content {
  max-width: 670px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  color: var(--teal);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
}

.eyebrow::before {
  content: "";
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--teal);
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.18;
  letter-spacing: 0;
}

h1 {
  font-size: clamp(42px, 6vw, 74px);
  max-width: 10em;
}

h2 {
  font-size: clamp(28px, 4vw, 44px);
}

h3 {
  font-size: 22px;
}

p {
  margin: 0;
}

.lead {
  max-width: 680px;
  margin-top: 22px;
  color: #39485c;
  font-size: 20px;
}

.hero-actions,
.section-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 32px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 11px 18px;
  color: #fff;
  background: var(--blue);
  border: 1px solid var(--blue);
  border-radius: 8px;
  font-weight: 800;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.button:hover {
  color: #fff;
  background: var(--blue-dark);
  transform: translateY(-1px);
  box-shadow: 0 12px 24px rgba(31, 111, 235, 0.2);
}

.button.secondary {
  color: var(--blue);
  background: #fff;
  border-color: #b7cef2;
}

.button.secondary:hover {
  color: var(--blue-dark);
  background: #edf5ff;
  box-shadow: none;
}

.button.ghost {
  color: var(--ink);
  background: transparent;
  border-color: var(--line);
}

.button.ghost:hover {
  color: var(--blue);
  background: #fff;
  box-shadow: none;
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  max-width: 640px;
  gap: 1px;
  margin-top: 42px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.metric {
  padding: 18px;
  background: rgba(255, 255, 255, 0.9);
}

.metric strong {
  display: block;
  color: var(--navy);
  font-size: 24px;
  line-height: 1.1;
}

.metric span {
  display: block;
  margin-top: 6px;
  color: var(--muted);
  font-size: 13px;
}

.section {
  padding: 76px 24px;
}

.section.white {
  background: #fff;
}

.section.compact {
  padding-top: 46px;
  padding-bottom: 46px;
}

.container {
  max-width: var(--max);
  margin: 0 auto;
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 34px;
}

.section-head p {
  max-width: 560px;
  color: var(--muted);
}

.grid {
  display: grid;
  gap: 18px;
}

.grid.three {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid.four {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.grid.two {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  min-width: 0;
}

.card h3 {
  margin-bottom: 10px;
}

.card p,
.card li {
  color: var(--muted);
}

.icon {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  margin-bottom: 16px;
  color: var(--blue);
  background: #eaf2ff;
  border-radius: 8px;
  font-weight: 900;
}

.icon.teal {
  color: var(--teal);
  background: #e8f7f6;
}

.icon.green {
  color: var(--green);
  background: #e9f6f0;
}

.icon.amber {
  color: var(--amber);
  background: #fff4df;
}

.page-hero {
  background: #fff;
  border-bottom: 1px solid var(--line);
}

.page-hero .container {
  padding: 58px 24px 54px;
}

.breadcrumb {
  margin: 0 0 16px;
  color: var(--muted);
  font-size: 14px;
}

.breadcrumb a {
  color: var(--muted);
}

.page-hero h1 {
  font-size: clamp(36px, 5vw, 56px);
  max-width: 13em;
}

.page-hero .lead {
  max-width: 760px;
}

.notice {
  padding: 18px 20px;
  color: #553600;
  background: #fff7e8;
  border: 1px solid #f2d7a8;
  border-radius: 8px;
}

.feature-list {
  padding-left: 18px;
  margin: 14px 0 0;
}

.feature-list li + li {
  margin-top: 8px;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(320px, 0.98fr);
  gap: 34px;
  align-items: center;
}

.product-shot {
  padding: 10px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.product-shot img {
  width: 100%;
  border-radius: 4px;
}

.steps {
  counter-reset: step;
  display: grid;
  gap: 18px;
}

.step {
  position: relative;
  padding: 22px 22px 22px 72px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 22px;
  top: 22px;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  color: #fff;
  background: var(--blue);
  border-radius: 8px;
  font-weight: 900;
}

.step h3 {
  margin-bottom: 8px;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.data-table th,
.data-table td {
  padding: 15px 16px;
  text-align: left;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.data-table th {
  color: var(--navy);
  background: #eef4fb;
}

.data-table tr:last-child td {
  border-bottom: 0;
}

.check {
  color: var(--green);
  font-weight: 900;
}

.dash {
  color: #9aa5b3;
}

.download-panel {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 22px;
  align-items: stretch;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.download-main {
  padding: 30px;
}

.download-side {
  padding: 30px;
  background: #eef7f7;
  border-left: 1px solid var(--line);
}

.spec-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-top: 22px;
}

.spec-list div {
  padding: 13px 14px;
  background: #f8fafc;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.spec-list strong {
  display: block;
  color: var(--navy);
}

.spec-list span {
  color: var(--muted);
  font-size: 14px;
}

.faq {
  display: grid;
  gap: 12px;
}

.faq-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

.faq-question {
  width: 100%;
  min-height: 54px;
  padding: 15px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  color: var(--ink);
  background: #fff;
  border: 0;
  cursor: pointer;
  text-align: left;
  font-weight: 800;
}

.faq-question::after {
  content: "+";
  font-size: 24px;
  color: var(--blue);
}

.faq-item[open] .faq-question::after {
  content: "-";
}

.faq-answer {
  padding: 0 18px 18px;
  color: var(--muted);
}

.source-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding: 0;
  margin: 18px 0 0;
  list-style: none;
}

.source-list a {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 6px 10px;
  color: #39485c;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 8px;
  font-size: 14px;
}

.site-footer {
  color: #c7d0dc;
  background: var(--navy);
}

.footer-grid {
  max-width: var(--max);
  margin: 0 auto;
  padding: 44px 24px;
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 30px;
}

.site-footer h2,
.site-footer h3 {
  color: #fff;
  font-size: 18px;
  margin-bottom: 12px;
}

.site-footer p,
.site-footer a {
  color: #c7d0dc;
  font-size: 14px;
}

.site-footer a {
  display: block;
  margin-top: 8px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
}

.footer-bottom .container {
  padding: 16px 24px;
  color: #aab6c4;
  font-size: 13px;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: none;
  place-items: center;
  padding: 20px;
  background: rgba(12, 24, 39, 0.58);
}

.modal-backdrop.is-open {
  display: grid;
}

.modal {
  width: min(760px, 100%);
  max-height: min(90vh, 760px);
  overflow: auto;
  background: #fff;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.modal-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 22px 24px;
  border-bottom: 1px solid var(--line);
}

.modal-head h2 {
  font-size: 24px;
}

.modal-close {
  width: 40px;
  height: 40px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  cursor: pointer;
  font-size: 24px;
  line-height: 1;
}

.modal-body {
  padding: 24px;
}

.qr-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 18px;
}

.qr-box {
  padding: 18px;
  text-align: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fafc;
}

.qr-box img {
  width: 180px;
  height: 180px;
  margin: 0 auto 14px;
  background: #fff;
  border: 8px solid #fff;
}

.qr-box h3 {
  font-size: 18px;
  margin-bottom: 6px;
}

.qr-box p {
  color: var(--muted);
  font-size: 14px;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.tag {
  padding: 6px 10px;
  color: #334155;
  background: #eef4fb;
  border: 1px solid var(--line);
  border-radius: 8px;
  font-size: 13px;
  font-weight: 700;
}

@media (max-width: 980px) {
  .hero {
    min-height: auto;
    background-position: right -120px center;
    background-size: 620px auto;
  }

  .hero::before {
    width: 72%;
  }

  .grid.four,
  .grid.three {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .split,
  .download-panel,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .download-side {
    border-left: 0;
    border-top: 1px solid var(--line);
  }
}

@media (max-width: 760px) {
  .nav-wrap {
    min-height: 64px;
    padding: 0 16px;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 64px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px 16px 16px;
    background: #fff;
    border-bottom: 1px solid var(--line);
  }

  .site-nav.is-open {
    display: flex;
  }

  .site-nav a {
    padding: 12px;
  }

  .hero {
    min-height: 720px;
    background-size: 520px auto;
    background-position: center bottom 28px;
    align-items: start;
  }

  .hero::before {
    width: 100%;
    height: 58%;
    bottom: auto;
  }

  .hero-inner {
    padding: 42px 18px 320px;
  }

  h1 {
    font-size: 42px;
  }

  .lead {
    font-size: 18px;
  }

  .hero-metrics,
  .grid.two,
  .grid.three,
  .grid.four,
  .spec-list,
  .qr-grid {
    grid-template-columns: 1fr;
  }

  .section,
  .page-hero .container {
    padding-left: 18px;
    padding-right: 18px;
  }

  .section-head {
    display: block;
  }

  .section-head p {
    margin-top: 14px;
  }

  .data-table {
    display: block;
    overflow-x: auto;
    white-space: nowrap;
  }
}