/* ============================================================
   Quanwen Technology Limited
   Graphite Monochrome — Dark Theme
   ============================================================ */

:root {
  --bg: #101418;
  --bg-raise: #161c22;
  --bg-editor: #1a2026;
  --panel-line: #2c343e;
  --text: #e8ecf0;
  --text-soft: #c9d4dc;
  --text-dim: #9aa3ad;
  --graphite: #6b7280;
  --silver: #9aa3ad;
  --mist: #c9d4dc;
  --hairline: #262d35;
  --graphite-dark: #4b515b;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background-color: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

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

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

.container {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ------------------------------------------------------------
   Window Chrome Navigation
   ------------------------------------------------------------ */

.win-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--bg);
  border-bottom: 1px solid var(--graphite);
}

.win-nav-inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
  height: 62px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.win-left {
  display: flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}

.win-dots {
  display: flex;
  align-items: center;
  gap: 7px;
  flex-shrink: 0;
}

.win-dot {
  width: 11px;
  height: 11px;
  border-radius: 3px;
  display: block;
}

.win-dot-g { background-color: var(--graphite); }
.win-dot-s { background-color: var(--silver); }
.win-dot-l { background-color: var(--mist); }

.win-brand {
  font-weight: 700;
  letter-spacing: 0.16em;
  font-size: 15px;
  color: var(--text);
  white-space: nowrap;
}

.win-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.win-links a {
  color: var(--text-dim);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.02em;
  padding: 6px 0;
  position: relative;
  transition: color 0.18s ease;
}

.win-links a:hover {
  color: var(--text);
}

.win-links a.active {
  color: var(--text);
}

.win-links a.active::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background-color: var(--graphite);
}

.win-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.win-cta {
  display: inline-block;
  background-color: var(--graphite);
  color: var(--text);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
  padding: 9px 16px;
  border-radius: 5px;
  white-space: nowrap;
  transition: background-color 0.18s ease;
}

.win-cta:hover {
  background-color: var(--silver);
  color: var(--bg);
}

.win-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
}

.win-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--text);
  border-radius: 1px;
}

/* ------------------------------------------------------------
   Buttons
   ------------------------------------------------------------ */

.btn {
  display: inline-block;
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0.01em;
  padding: 14px 26px;
  border-radius: 6px;
  border: 1px solid transparent;
  transition: background-color 0.18s ease, border-color 0.18s ease, color 0.18s ease;
}

.btn-primary {
  background-color: var(--graphite);
  color: var(--text);
}

.btn-primary:hover {
  background-color: var(--silver);
  color: var(--bg);
}

.btn-ghost {
  background-color: transparent;
  color: var(--text-soft);
  border-color: var(--silver);
}

.btn-ghost:hover {
  border-color: var(--text);
  color: var(--text);
}

.btn-light {
  background-color: var(--text);
  color: var(--bg);
}

.btn-light:hover {
  background-color: var(--mist);
  color: var(--bg);
}

/* ------------------------------------------------------------
   Terminal Window Hero
   ------------------------------------------------------------ */

.terminal-hero {
  padding: 88px 0 96px;
  background-color: var(--bg);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
}

.eyebrow-chip {
  display: inline-block;
  background-color: var(--graphite);
  color: var(--mist);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  padding: 7px 14px;
  border-radius: 4px;
  margin-bottom: 26px;
}

.hero-title {
  font-size: 46px;
  line-height: 1.14;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  margin-bottom: 22px;
}

.hero-sub {
  font-size: 17px;
  line-height: 1.7;
  color: var(--text-dim);
  margin-bottom: 34px;
  max-width: 560px;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

/* Editor window */

.editor-window {
  background-color: var(--bg-editor);
  border: 1px solid var(--panel-line);
  border-radius: 12px;
  padding: 18px 20px 22px;
}

.editor-titlebar {
  display: flex;
  align-items: center;
  gap: 7px;
  padding-bottom: 14px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--hairline);
}

.ed-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: block;
}

.ed-dot-g { background-color: var(--graphite); }
.ed-dot-s { background-color: var(--silver); }
.ed-dot-l { background-color: var(--mist); }

.editor-title-line {
  flex: 1;
  height: 1px;
  background-color: var(--hairline);
  margin-left: 6px;
}

.editor-body {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.code-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.bar {
  height: 12px;
  border-radius: 6px;
  display: block;
}

.bar-g { background-color: var(--graphite); }
.bar-s { background-color: var(--silver); }
.bar-l { background-color: var(--mist); }

.w22 { width: 22%; }
.w24 { width: 24%; }
.w30 { width: 30%; }
.w34 { width: 34%; }
.w38 { width: 38%; }
.w40 { width: 40%; }
.w72 { width: 72%; }

.caret {
  width: 2px;
  height: 16px;
  background-color: var(--mist);
  display: block;
  border-radius: 1px;
  flex-shrink: 0;
}

/* ------------------------------------------------------------
   Statement row
   ------------------------------------------------------------ */

.statement-row {
  background-color: var(--bg);
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
}

.statement {
  font-size: 26px;
  line-height: 1.5;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
  text-align: center;
  max-width: 900px;
  margin: 0 auto;
  padding: 72px 0;
}

/* ------------------------------------------------------------
   Section headers
   ------------------------------------------------------------ */

.section-head {
  margin-bottom: 44px;
}

.section-eyebrow {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
  margin-bottom: 14px;
}

.section-title {
  font-size: 34px;
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
}

.section-intro {
  font-size: 17px;
  color: var(--text-dim);
  margin-top: 14px;
  max-width: 640px;
}

/* ------------------------------------------------------------
   Service list (numbered rows)
   ------------------------------------------------------------ */

.service-list {
  background-color: var(--bg);
  padding: 84px 0;
}

.service-row {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 28px;
  align-items: baseline;
  padding: 26px 0;
  border-bottom: 1px solid var(--hairline);
}

.service-row:first-of-type {
  border-top: 1px solid var(--hairline);
}

.service-num {
  font-size: 30px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--graphite);
  font-variant-numeric: tabular-nums;
}

.service-name {
  font-size: 22px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
}

.service-desc {
  font-size: 16px;
  color: var(--text-dim);
  margin-top: 4px;
  grid-column: 2;
}

/* ------------------------------------------------------------
   Log rows (version history)
   ------------------------------------------------------------ */

.log-rows {
  background-color: var(--bg);
  padding: 84px 0;
}

.log-row {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 28px;
  align-items: baseline;
  padding: 22px 0;
  border-bottom: 1px solid var(--hairline);
}

.log-row:first-of-type {
  border-top: 1px solid var(--hairline);
}

.log-version {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.log-year {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--graphite);
  font-variant-numeric: tabular-nums;
}

.log-note {
  font-size: 16px;
  color: var(--text-dim);
}

/* ------------------------------------------------------------
   Principle rows
   ------------------------------------------------------------ */

.principle-rows {
  background-color: var(--bg);
  padding: 84px 0;
}

.principle-row {
  display: grid;
  grid-template-columns: 14px 1fr;
  gap: 24px;
  align-items: start;
  padding: 30px 0;
  border-bottom: 1px solid var(--hairline);
}

.principle-row:first-of-type {
  border-top: 1px solid var(--hairline);
}

.principle-marker {
  width: 12px;
  height: 12px;
  background-color: var(--graphite);
  border-radius: 2px;
  margin-top: 8px;
}

.principle-name {
  font-size: 22px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
  margin-bottom: 8px;
}

.principle-text {
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-dim);
  max-width: 720px;
}

/* ------------------------------------------------------------
   FAQ accordion
   ------------------------------------------------------------ */

.faq-accordion {
  background-color: var(--bg);
  padding: 84px 0;
}

.faq-list {
  max-width: 820px;
}

.faq-item {
  border-bottom: 1px solid var(--hairline);
}

.faq-item:first-child {
  border-top: 1px solid var(--hairline);
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  padding: 22px 0;
  font-size: 17px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
}

.faq-question::after {
  content: "+";
  font-size: 24px;
  font-weight: 400;
  color: var(--graphite);
  line-height: 1;
  transition: transform 0.18s ease;
}

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

.faq-panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.faq-item.open .faq-panel {
  max-height: 400px;
}

.faq-panel p {
  padding: 0 0 22px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-dim);
  max-width: 720px;
}

/* ------------------------------------------------------------
   CTA band
   ------------------------------------------------------------ */

.cta-band {
  background-color: var(--graphite);
}

.cta-inner {
  padding: 72px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.cta-title {
  font-size: 30px;
  line-height: 1.25;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  margin-bottom: 12px;
}

.cta-sub {
  font-size: 16px;
  color: var(--mist);
  max-width: 540px;
}

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

.cmd-footer {
  background-color: var(--bg);
  border-top: 2px solid var(--graphite);
}

.cmd-cols {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 1.4fr;
  gap: 44px;
  padding: 60px 0 44px;
}

.cmd-brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 14px;
}

.cmd-dots {
  display: flex;
  align-items: center;
  gap: 7px;
}

.cmd-dot {
  width: 10px;
  height: 10px;
  border-radius: 3px;
  display: block;
}

.cmd-dot-g { background-color: var(--graphite); }
.cmd-dot-s { background-color: var(--silver); }
.cmd-dot-l { background-color: var(--mist); }

.cmd-wordmark {
  font-weight: 700;
  letter-spacing: 0.16em;
  font-size: 16px;
  color: var(--text);
}

.cmd-desc {
  font-size: 15px;
  color: var(--text-dim);
  line-height: 1.65;
  max-width: 320px;
}

.cmd-col-title {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--mist);
  margin-bottom: 18px;
}

.cmd-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 11px;
}

.cmd-links a {
  color: var(--text-dim);
  font-size: 15px;
  transition: color 0.18s ease;
}

.cmd-links a:hover {
  color: var(--text);
}

.cmd-contact {
  font-size: 15px;
  color: var(--text-dim);
  margin-bottom: 10px;
}

.cmd-contact a {
  color: var(--text-soft);
}

.cmd-contact a:hover {
  color: var(--text);
}

.cmd-address {
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-dim);
  max-width: 300px;
}

.cmd-legal {
  border-top: 1px solid var(--hairline);
  padding: 22px 0;
  text-align: center;
  font-size: 14px;
  color: var(--text-dim);
}

.cmd-legal a {
  color: var(--text-soft);
}

.cmd-legal a:hover {
  color: var(--text);
}

/* ------------------------------------------------------------
   Secondary pages: page hero
   ------------------------------------------------------------ */

.page-hero {
  background-color: var(--bg);
  border-bottom: 1px solid var(--hairline);
  padding: 76px 0 64px;
}

.page-hero .eyebrow-chip {
  margin-bottom: 20px;
}

.page-title {
  font-size: 42px;
  line-height: 1.15;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  margin-bottom: 18px;
}

.page-intro {
  font-size: 17px;
  line-height: 1.7;
  color: var(--text-dim);
  max-width: 680px;
}

/* ------------------------------------------------------------
   Services page: service blocks
   ------------------------------------------------------------ */

.services-detail {
  background-color: var(--bg);
  padding: 84px 0;
}

.service-block {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 30px;
  padding: 44px 0;
  border-bottom: 1px solid var(--hairline);
}

.service-block:first-of-type {
  border-top: 1px solid var(--hairline);
}

.service-block-num {
  font-size: 28px;
  font-weight: 700;
  color: var(--graphite);
  font-variant-numeric: tabular-nums;
}

.service-block-title {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
  margin-bottom: 12px;
}

.service-block p {
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-dim);
  margin-bottom: 14px;
  max-width: 760px;
}

.service-block p:last-child {
  margin-bottom: 0;
}

.service-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.service-tag {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--mist);
  background-color: var(--bg-raise);
  border: 1px solid var(--hairline);
  padding: 6px 14px;
  border-radius: 4px;
}

/* ------------------------------------------------------------
   Process overview
   ------------------------------------------------------------ */

.process {
  background-color: var(--bg);
  padding: 84px 0;
}

.process-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 26px;
  margin-top: 8px;
}

.process-step {
  border-top: 2px solid var(--graphite);
  padding-top: 22px;
}

.process-step-num {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--mist);
  margin-bottom: 12px;
  font-variant-numeric: tabular-nums;
}

.process-step h3 {
  font-size: 19px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
}

.process-step p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-dim);
}

/* ------------------------------------------------------------
   Stats band (counters)
   ------------------------------------------------------------ */

.stats-band {
  background-color: var(--bg-raise);
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  padding: 60px 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  text-align: center;
}

.stat-value {
  font-size: 44px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

.stat-label {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--mist);
  margin-top: 12px;
}

/* ------------------------------------------------------------
   Contact page
   ------------------------------------------------------------ */

.contact-main {
  background-color: var(--bg);
  padding: 72px 0;
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: start;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-field label {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--mist);
}

.form-field input,
.form-field textarea {
  background-color: var(--bg-raise);
  border: 1px solid var(--hairline);
  border-radius: 6px;
  color: var(--text);
  font-size: 16px;
  font-family: inherit;
  padding: 13px 15px;
  outline: none;
  transition: border-color 0.18s ease;
}

.form-field input:focus,
.form-field textarea:focus {
  border-color: var(--graphite);
}

.form-field textarea {
  min-height: 150px;
  resize: vertical;
}

.form-note {
  font-size: 14px;
  color: var(--text-dim);
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 30px;
}

.info-block {
  border-left: 2px solid var(--graphite);
  padding-left: 20px;
}

.info-block h3 {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--mist);
  margin-bottom: 10px;
}

.info-block p {
  font-size: 16px;
  color: var(--text-soft);
  line-height: 1.65;
}

.info-block a {
  color: var(--text-soft);
}

.info-block a:hover {
  color: var(--text);
}

.contact-faq {
  background-color: var(--bg);
  padding: 0 0 84px;
}

/* ------------------------------------------------------------
   Scroll reveal
   ------------------------------------------------------------ */

.fade-up {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ------------------------------------------------------------
   Responsive
   ------------------------------------------------------------ */

@media (max-width: 960px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 44px;
  }

  .hero-title {
    font-size: 38px;
  }

  .cmd-cols {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }

  .cmd-brand {
    grid-column: 1 / -1;
  }

  .process-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 34px;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 36px;
  }

  .contact-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }
}

@media (max-width: 820px) {
  .win-toggle {
    display: flex;
  }

  .win-cta {
    display: none;
  }

  .win-links {
    position: absolute;
    top: 62px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background-color: var(--bg-raise);
    border-bottom: 1px solid var(--graphite);
    padding: 8px 24px 16px;
    display: none;
  }

  .win-links.open {
    display: flex;
  }

  .win-links a {
    padding: 14px 0;
    border-bottom: 1px solid var(--hairline);
    font-size: 15px;
  }

  .win-links a:last-child {
    border-bottom: none;
  }

  .win-links a.active::after {
    display: none;
  }

  .statement {
    font-size: 21px;
    padding: 52px 0;
  }

  .section-title {
    font-size: 28px;
  }

  .service-row {
    grid-template-columns: 72px 1fr;
    gap: 18px;
  }

  .service-num {
    font-size: 24px;
  }

  .service-desc {
    grid-column: 1 / -1;
  }

  .log-row {
    grid-template-columns: 120px 1fr;
    gap: 18px;
  }

  .cta-inner {
    flex-direction: column;
    align-items: flex-start;
    padding: 56px 24px;
  }

  .service-block {
    grid-template-columns: 1fr;
    gap: 14px;
  }
}

@media (max-width: 560px) {
  .hero-title {
    font-size: 31px;
  }

  .page-title {
    font-size: 32px;
  }

  .cmd-cols {
    grid-template-columns: 1fr;
    gap: 34px;
  }

  .process-grid {
    grid-template-columns: 1fr;
  }

  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }

  .stat-value {
    font-size: 34px;
  }
}