:root {
  --ink: #172033;
  --muted: #657084;
  --line: #dce3ee;
  --paper: #f7f9fc;
  --white: #ffffff;
  --blue: #246bfe;
  --cyan: #16a6c7;
  --green: #18a66a;
  --amber: #f0a62b;
  --red: #ef5555;
  --shadow: 0 22px 70px rgba(28, 45, 74, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", Arial, sans-serif;
  line-height: 1.6;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 28px;
  padding: 14px clamp(18px, 4vw, 56px);
  background: rgba(247, 249, 252, 0.86);
  border-bottom: 1px solid rgba(220, 227, 238, 0.76);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 210px;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  color: var(--white);
  font-weight: 800;
  background: linear-gradient(135deg, var(--blue), var(--green));
  border-radius: 8px;
}

.brand strong,
.brand small {
  display: block;
}

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

.nav-links {
  display: flex;
  justify-content: center;
  gap: 28px;
  flex: 1;
  color: #344156;
  font-size: 15px;
}

.nav-links a {
  padding: 8px 0;
}

.header-action,
.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border-radius: 8px;
  font-weight: 700;
}

.header-action,
.primary-button {
  color: var(--white);
  background: var(--blue);
  box-shadow: 0 14px 30px rgba(36, 107, 254, 0.22);
}

.secondary-button {
  color: var(--ink);
  background: var(--white);
  border: 1px solid var(--line);
}

.menu-button {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.menu-button span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  background: var(--ink);
}

.mobile-quick-panel,
.mobile-scenario-strip,
.mobile-action-bar {
  display: none;
}

.section,
.section-band,
.hero {
  padding: 88px clamp(18px, 5vw, 72px);
}

.section {
  background: var(--white);
}

.section-band {
  background:
    radial-gradient(circle at 12% 12%, rgba(36, 107, 254, 0.12), transparent 32%),
    linear-gradient(180deg, #eef5ff 0%, #f8fbff 100%);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(360px, 0.98fr);
  align-items: center;
  gap: clamp(32px, 6vw, 80px);
  min-height: calc(100vh - 72px);
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--blue);
  font-weight: 800;
  letter-spacing: 0;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 820px;
  margin-bottom: 22px;
  font-size: clamp(38px, 6vw, 72px);
  line-height: 1.08;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  font-size: clamp(28px, 4vw, 46px);
  line-height: 1.16;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 10px;
  font-size: 22px;
}

.hero-lead,
.section-heading p,
.feature-copy p,
.shop-layout p,
.calculator p,
.contact p {
  color: var(--muted);
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin: 32px 0;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  max-width: 620px;
  margin: 0;
}

.hero-stats div {
  padding: 16px;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(220, 227, 238, 0.9);
  border-radius: 8px;
}

.hero-stats dt {
  font-size: 26px;
  font-weight: 900;
}

.hero-stats dd {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}

.hero-visual {
  position: relative;
  min-height: 620px;
}

.hero-banner {
  position: absolute;
  top: 24px;
  right: 0;
  width: min(92%, 610px);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.phone-shell {
  position: absolute;
  left: 0;
  bottom: 6px;
  width: min(58%, 410px);
  padding: 12px;
  background: #101623;
  border-radius: 28px;
  box-shadow: var(--shadow);
}

.phone-shell img {
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 18px;
}

.status-panel {
  position: absolute;
  right: 12px;
  bottom: 70px;
  display: grid;
  grid-template-columns: auto 1fr;
  column-gap: 10px;
  width: 230px;
  padding: 16px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.status-dot {
  width: 11px;
  height: 11px;
  margin-top: 8px;
  background: var(--green);
  border-radius: 50%;
  box-shadow: 0 0 0 6px rgba(24, 166, 106, 0.12);
}

.status-panel small {
  grid-column: 2;
  color: var(--muted);
}

.trust-strip {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  padding: 24px clamp(18px, 5vw, 72px);
  background: #101827;
}

.trust-strip span {
  color: #dfe8f7;
  padding: 8px 14px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
}

.section-heading {
  max-width: 780px;
  margin: 0 auto 42px;
  text-align: center;
}

.section-heading.compact {
  margin-bottom: 32px;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
  max-width: 1180px;
  margin: 0 auto;
}

.mode-card {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 24px;
  align-items: center;
  padding: 22px;
  background: #fbfdff;
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 14px 34px rgba(28, 45, 74, 0.08);
  transition: transform 180ms ease, border-color 180ms ease;
}

.mode-card:hover,
.mode-card.active {
  transform: translateY(-4px);
  border-color: rgba(36, 107, 254, 0.45);
}

.mode-card img {
  width: 100%;
  border-radius: 8px;
}

.mode-tag {
  display: inline-flex;
  margin-bottom: 12px;
  padding: 4px 10px;
  color: var(--green);
  background: rgba(24, 166, 106, 0.1);
  border-radius: 8px;
  font-weight: 800;
  font-size: 13px;
}

.mode-card p,
.mode-card li,
.workflow p,
.tools-grid p,
.faq-list p,
.shop-points span {
  color: var(--muted);
}

.mode-card ul {
  padding-left: 18px;
  margin-bottom: 0;
}

.workflow {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  max-width: 1180px;
  margin: 0 auto;
}

.workflow article,
.tools-grid article,
.upload-panel,
.calc-card,
.contact-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 14px 34px rgba(28, 45, 74, 0.08);
}

.workflow article {
  padding: 24px;
}

.workflow span {
  display: inline-flex;
  margin-bottom: 18px;
  color: var(--amber);
  font-weight: 900;
}

.feature-layout,
.calculator,
.contact {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 0.75fr);
  align-items: center;
  gap: clamp(24px, 5vw, 70px);
}

.file-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.file-chips span {
  padding: 10px 14px;
  color: #26344b;
  background: #eef4fb;
  border: 1px solid #d8e3f0;
  border-radius: 8px;
  font-weight: 700;
}

.upload-panel {
  padding: 24px;
}

.upload-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.upload-head span {
  color: var(--muted);
}

.upload-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.upload-grid div {
  display: grid;
  min-height: 116px;
  place-items: center;
  padding: 16px;
  background: #f4f7fb;
  border: 1px solid var(--line);
  border-radius: 8px;
  text-align: center;
  font-weight: 800;
}

.upload-grid img {
  width: 36px;
  height: 36px;
  object-fit: contain;
  margin-bottom: 8px;
}

.shop-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(260px, 360px);
  align-items: center;
  gap: clamp(24px, 5vw, 70px);
  max-width: 1120px;
  margin: 0 auto;
}

.shop-points {
  display: grid;
  gap: 12px;
  margin-top: 26px;
}

.shop-points div {
  display: grid;
  gap: 3px;
  padding: 16px;
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.detail-shot {
  max-height: 620px;
  width: 100%;
  object-fit: cover;
  object-position: top;
  border: 12px solid #101623;
  border-radius: 28px;
  box-shadow: var(--shadow);
}

.tools-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr 1fr;
  gap: 18px;
  max-width: 1180px;
  margin: 0 auto;
}

.tools-grid article {
  padding: 22px;
}

.tools-grid img {
  margin: -8px -8px 18px;
  width: calc(100% + 16px);
  border-radius: 8px;
}

.calc-card {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  padding: 24px;
}

.calc-card label {
  display: grid;
  gap: 8px;
  color: #334158;
  font-weight: 800;
}

.calc-card input,
.calc-card select {
  width: 100%;
  min-height: 44px;
  padding: 0 12px;
  color: var(--ink);
  background: #f8fafc;
  border: 1px solid var(--line);
  border-radius: 8px;
  font: inherit;
}

.calc-result {
  grid-column: 1 / -1;
  padding: 20px;
  color: var(--white);
  background: linear-gradient(135deg, var(--ink), var(--blue));
  border-radius: 8px;
  font-size: 34px;
  font-weight: 900;
  text-align: center;
}

.faq-list {
  display: grid;
  gap: 12px;
  max-width: 860px;
  margin: 0 auto;
}

.faq-list details {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 10px 26px rgba(28, 45, 74, 0.06);
}

.faq-list summary {
  cursor: pointer;
  padding: 18px 20px;
  font-weight: 900;
}

.faq-list p {
  margin: 0;
  padding: 0 20px 20px;
}

.contact {
  background: #111827;
  color: var(--white);
}

.contact p,
.contact .eyebrow {
  color: #c9d7ee;
}

.contact-card {
  display: grid;
  gap: 14px;
  padding: 28px;
  color: var(--ink);
}

.contact-card span {
  color: var(--muted);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 26px clamp(18px, 5vw, 72px);
  color: #c9d7ee;
  background: #0c1220;
}

@media (max-width: 980px) {
  .site-header {
    flex-wrap: wrap;
  }

  .nav-links,
  .header-action {
    display: none;
  }

  .menu-button {
    display: block;
    margin-left: auto;
  }

  .site-header.menu-open .nav-links,
  .site-header.menu-open .header-action {
    display: flex;
    width: 100%;
  }

  .site-header.menu-open .nav-links {
    flex-direction: column;
    gap: 6px;
    padding-top: 10px;
  }

  .site-header.menu-open .nav-links a {
    padding: 12px 14px;
    background: var(--white);
    border: 1px solid var(--line);
    border-radius: 8px;
  }

  .site-header.menu-open .header-action {
    margin-top: 8px;
  }

  .hero,
  .feature-layout,
  .calculator,
  .contact,
  .shop-layout {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
  }

  .hero-visual {
    min-height: 560px;
  }

  .mode-grid,
  .workflow,
  .tools-grid {
    grid-template-columns: 1fr;
  }

  .mode-card {
    grid-template-columns: 140px 1fr;
  }
}

@media (max-width: 640px) {
  body {
    padding-bottom: 76px;
  }

  .site-header {
    gap: 10px;
    padding: 10px 14px;
    background: rgba(255, 255, 255, 0.94);
  }

  .brand {
    gap: 10px;
  }

  .brand-mark {
    width: 36px;
    height: 36px;
    border-radius: 8px;
  }

  .brand strong {
    font-size: 15px;
  }

  .brand small {
    font-size: 10px;
  }

  .menu-button {
    width: 38px;
    height: 38px;
  }

  .mobile-quick-panel {
    position: sticky;
    top: 58px;
    z-index: 19;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    padding: 8px 14px;
    background: rgba(247, 249, 252, 0.92);
    border-bottom: 1px solid rgba(220, 227, 238, 0.76);
    backdrop-filter: blur(14px);
  }

  .mobile-quick-panel span {
    display: grid;
    min-height: 34px;
    place-items: center;
    color: #26344b;
    background: var(--white);
    border: 1px solid var(--line);
    border-radius: 8px;
    font-size: 12px;
    font-weight: 800;
  }

  .section,
  .section-band,
  .hero {
    padding: 46px 18px;
  }

  .hero {
    gap: 20px;
    padding-top: 24px;
    padding-bottom: 24px;
    text-align: left;
  }

  .eyebrow {
    margin-bottom: 10px;
    font-size: 13px;
  }

  h1 {
    margin-bottom: 16px;
    font-size: 31px;
    line-height: 1.14;
  }

  h2 {
    font-size: 28px;
    line-height: 1.2;
  }

  h3 {
    font-size: 19px;
  }

  .hero-lead,
  .section-heading p,
  .feature-copy p,
  .shop-layout p,
  .calculator p,
  .contact p {
    font-size: 15px;
  }

  .hero-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin: 20px 0 16px;
  }

  .primary-button,
  .secondary-button {
    min-height: 46px;
    padding: 0 12px;
    font-size: 14px;
  }

  .hero-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 8px;
  }

  .hero-stats div {
    padding: 12px 8px;
    text-align: center;
  }

  .hero-stats dt {
    font-size: 22px;
  }

  .hero-stats dd {
    font-size: 11px;
  }

  .hero-visual {
    min-height: 274px;
    margin: 0 -6px;
  }

  .hero-banner {
    top: 0;
    left: 8px;
    right: auto;
    width: calc(100% - 16px);
    border-radius: 8px;
  }

  .phone-shell {
    left: 14px;
    bottom: 8px;
    width: 43%;
    padding: 8px;
    border-radius: 22px;
  }

  .phone-shell img {
    border-radius: 15px;
  }

  .status-panel {
    right: 8px;
    bottom: 16px;
    width: 166px;
    padding: 13px;
    border-radius: 8px;
  }

  .status-panel strong {
    font-size: 14px;
  }

  .status-panel small {
    font-size: 12px;
  }

  .trust-strip {
    display: none;
  }

  .mobile-scenario-strip {
    display: grid;
    gap: 10px;
    padding: 16px 18px;
    background: #101827;
  }

  .mobile-scenario-strip a {
    display: grid;
    gap: 2px;
    padding: 14px 16px;
    color: var(--white);
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.14);
    border-radius: 8px;
  }

  .mobile-scenario-strip span {
    color: #c9d7ee;
    font-size: 13px;
  }

  .section-heading {
    margin-bottom: 24px;
    text-align: left;
  }

  .mode-grid,
  .workflow,
  .tools-grid {
    gap: 14px;
  }

  .mode-card {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 16px;
  }

  .mode-card img {
    max-height: 210px;
    object-fit: cover;
    object-position: top;
  }

  .mode-card ul {
    padding-left: 16px;
  }

  .workflow {
    position: relative;
  }

  .workflow article {
    display: grid;
    grid-template-columns: 46px 1fr;
    column-gap: 12px;
    padding: 18px;
  }

  .workflow span {
    grid-row: span 2;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    margin: 0;
    color: var(--white);
    background: var(--blue);
    border-radius: 8px;
  }

  .workflow h3 {
    margin-bottom: 4px;
  }

  .workflow p {
    margin: 0;
    font-size: 14px;
  }

  .file-chips {
    gap: 8px;
  }

  .file-chips span {
    padding: 8px 10px;
    font-size: 13px;
  }

  .upload-panel {
    padding: 18px;
  }

  .upload-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
  }

  .upload-grid div {
    min-height: 96px;
    padding: 12px 8px;
    font-size: 13px;
  }

  .shop-points div,
  .tools-grid article,
  .faq-list details,
  .contact-card,
  .calc-card {
    border-radius: 8px;
  }

  .detail-shot {
    max-height: 460px;
    border-width: 8px;
    border-radius: 22px;
  }

  .tools-grid article {
    padding: 18px;
  }

  .calc-card {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 18px;
  }

  .calc-card input,
  .calc-card select {
    min-height: 46px;
  }

  .calc-result {
    padding: 16px;
    font-size: 30px;
  }

  .faq-list summary {
    padding: 16px;
  }

  .faq-list p {
    padding: 0 16px 16px;
    font-size: 14px;
  }

  .contact {
    gap: 20px;
  }

  .contact-card {
    padding: 20px;
  }

  .site-footer {
    flex-direction: column;
    padding-bottom: 28px;
    font-size: 13px;
  }

  .mobile-action-bar {
    position: fixed;
    right: 12px;
    bottom: 12px;
    left: 12px;
    z-index: 30;
    display: grid;
    grid-template-columns: 1fr 0.8fr 1.2fr;
    gap: 8px;
    padding: 8px;
    background: rgba(255, 255, 255, 0.94);
    border: 1px solid rgba(220, 227, 238, 0.9);
    border-radius: 8px;
    box-shadow: 0 18px 44px rgba(16, 24, 39, 0.18);
    backdrop-filter: blur(14px);
  }

  .mobile-action-bar a {
    display: grid;
    min-height: 42px;
    place-items: center;
    color: #344156;
    background: #eef4fb;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 900;
  }

  .mobile-action-bar .mobile-action-primary {
    color: var(--white);
    background: var(--blue);
  }
}