:root {
  --bg: #f7fafb;
  --surface: #ffffff;
  --ink: #07131f;
  --muted: #65717d;
  --line: rgba(7, 19, 31, 0.1);
  --teal: #28d6c6;
  --teal-dark: #13a99c;
  --blue: #147de8;
  --night: #071d25;
  --coral: #ff6b5f;
  --shadow: 0 24px 80px rgba(8, 28, 42, 0.12);
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
}

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

.site-header {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 20;
  background: rgba(247, 250, 251, 0.76);
  backdrop-filter: blur(22px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.site-header.is-scrolled {
  background: rgba(247, 250, 251, 0.92);
  border-bottom-color: var(--line);
}

.nav {
  width: min(1180px, calc(100% - 40px));
  height: 72px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
}

.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  filter: drop-shadow(0 12px 18px rgba(20, 125, 232, 0.18));
}

.brand-mark svg {
  width: 100%;
  height: 100%;
}

.brand-text {
  letter-spacing: 0;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-menu a {
  min-width: 64px;
  padding: 10px 14px;
  border-radius: 999px;
  color: #273747;
  font-size: 15px;
  text-align: center;
  transition: background 0.2s ease, color 0.2s ease;
}

.nav-menu a:hover {
  background: rgba(40, 214, 198, 0.14);
  color: #046d65;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: var(--surface);
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: var(--ink);
  border-radius: 2px;
}

.hero {
  width: min(1180px, calc(100% - 40px));
  min-height: 100vh;
  margin: 0 auto;
  padding: 130px 0 64px;
  display: grid;
  grid-template-columns: minmax(0, 0.96fr) minmax(360px, 1.04fr);
  align-items: center;
  gap: 58px;
}

.hero-copy {
  max-width: 680px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--teal-dark);
  font-size: 14px;
  font-weight: 800;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  letter-spacing: 0;
}

h1 {
  margin: 0;
  max-width: 640px;
  font-size: clamp(40px, 5.2vw, 68px);
  line-height: 1.08;
  font-weight: 800;
}

.hero-desc {
  margin: 24px 0 0;
  max-width: 570px;
  color: var(--muted);
  font-size: 19px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}

.btn {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 24px;
  border: 0;
  border-radius: 999px;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  color: #061717;
  background: var(--teal);
  box-shadow: 0 18px 34px rgba(40, 214, 198, 0.32);
}

.btn-secondary {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.82);
  border: 1px solid var(--line);
}

.hero-visual {
  position: relative;
  min-height: 560px;
  display: grid;
  place-items: center;
}

.hero-visual::before {
  content: "";
  position: absolute;
  inset: 8% 1% 6% 8%;
  background:
    linear-gradient(135deg, rgba(40, 214, 198, 0.18), rgba(20, 125, 232, 0.1)),
    repeating-linear-gradient(90deg, rgba(7, 19, 31, 0.05) 0 1px, transparent 1px 38px);
  border-radius: 38px;
  transform: rotate(-3deg);
}

.phone {
  position: absolute;
  width: 245px;
  height: 512px;
  padding: 14px;
  border: 1px solid rgba(255, 255, 255, 0.52);
  border-radius: 38px;
  background: #11171d;
  box-shadow: var(--shadow);
}

.phone::after {
  content: "";
  position: absolute;
  inset: 5px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 34px;
  pointer-events: none;
}

.phone-main {
  right: 44px;
  top: 12px;
  z-index: 2;
}

.phone-side {
  left: 34px;
  bottom: 12px;
  z-index: 3;
  width: 224px;
  height: 468px;
  transform: rotate(-5deg);
}

.phone-sensor {
  position: absolute;
  top: 15px;
  left: 50%;
  z-index: 3;
  width: 62px;
  height: 18px;
  border-radius: 999px;
  background: #03080c;
  transform: translateX(-50%);
}

.app-screen,
.menu-screen {
  position: relative;
  height: 100%;
  overflow: hidden;
  border-radius: 28px;
}

.app-screen {
  padding: 26px 16px 16px;
  background:
    linear-gradient(180deg, #071d25 0%, #0b2b32 100%),
    radial-gradient(circle at 28% 18%, rgba(40, 214, 198, 0.16), transparent 34%);
  color: #fff;
}

.app-status {
  display: flex;
  justify-content: space-between;
  color: rgba(255, 255, 255, 0.72);
  font-size: 11px;
}

.calculator-display {
  height: 128px;
  display: flex;
  align-items: flex-end;
  justify-content: flex-end;
  padding: 0 4px 20px;
  color: #dff9f5;
  font-size: 43px;
  font-weight: 300;
}

.calculator-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.calculator-grid span {
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.09);
  color: #ecfffd;
  font-weight: 700;
}

.calculator-grid span:nth-child(4n),
.calculator-grid span:last-child {
  background: var(--teal);
  color: #061717;
}

.calculator-grid .wide {
  grid-column: span 2;
  aspect-ratio: auto;
  border-radius: 18px;
}

.menu-screen {
  padding: 42px 20px 20px;
  background: linear-gradient(180deg, #ecfffb 0%, #1dbac2 42%, #109fae 100%);
}

.mini-logo {
  width: 48px;
  height: 48px;
  border: 6px solid #fff;
  border-radius: 50%;
  background: #2eaf73;
  box-shadow: 0 8px 22px rgba(7, 19, 31, 0.18);
}

.menu-screen h2 {
  margin: 8px 0 2px;
  color: #00a8c6;
  font-size: 18px;
}

.menu-screen p {
  margin: 0 0 18px;
  color: #095466;
  font-size: 12px;
}

.menu-screen ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.menu-screen li {
  padding: 14px 0;
  color: #fff;
  font-size: 15px;
  font-weight: 700;
  border-bottom: 1px solid rgba(255, 255, 255, 0.22);
}

.section {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
  padding: 92px 0;
}

.product-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  overflow: hidden;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--line);
  box-shadow: 0 20px 60px rgba(8, 28, 42, 0.08);
}

.metric {
  min-height: 168px;
  display: grid;
  align-content: center;
  gap: 10px;
  padding: 30px;
  background: rgba(255, 255, 255, 0.8);
}

.metric strong {
  font-size: clamp(30px, 4vw, 52px);
  line-height: 1;
}

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

.section-heading {
  max-width: 680px;
  margin-bottom: 34px;
}

.section-heading h2,
.detail-copy h2,
.contact-copy h2 {
  margin: 0;
  font-size: clamp(32px, 4vw, 56px);
  line-height: 1.12;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.feature-card {
  min-height: 308px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: rgba(255, 255, 255, 0.86);
  box-shadow: 0 20px 48px rgba(8, 28, 42, 0.08);
}

.feature-card h3 {
  margin: 74px 0 12px;
  font-size: 24px;
}

.feature-card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.75;
}

.feature-icon {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: #e9fbf8;
  color: var(--teal-dark);
  font-size: 22px;
  font-weight: 800;
}

.dark-card {
  background: var(--night);
  color: #fff;
}

.dark-card p {
  color: rgba(255, 255, 255, 0.72);
}

.accent-card {
  background: #eef6ff;
}

.accent-card .feature-icon {
  background: var(--blue);
  color: #fff;
}

.app-detail {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 0.7fr);
  gap: 56px;
  align-items: center;
}

.detail-copy p:not(.eyebrow) {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.9;
}

.detail-panel {
  padding: 14px;
  border-radius: 30px;
  background: var(--night);
  box-shadow: var(--shadow);
}

.detail-line {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 78px;
  padding: 0 18px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.72);
}

.detail-line:last-child {
  border-bottom: 0;
}

.detail-line strong {
  color: #fff;
  text-align: right;
}

.news-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.news-list article {
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: #fff;
}

.news-list time {
  color: var(--teal-dark);
  font-weight: 800;
}

.news-list h3 {
  min-height: 68px;
  margin: 18px 0 12px;
  font-size: 21px;
  line-height: 1.45;
}

.news-list p {
  margin: 0;
  color: var(--muted);
  line-height: 1.75;
}

.contact {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(340px, 0.8fr);
  gap: 48px;
  align-items: start;
  padding-bottom: 110px;
}

.contact-copy p:not(.eyebrow) {
  max-width: 520px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.85;
}

.contact-info {
  display: grid;
  gap: 8px;
  margin-top: 30px;
  color: var(--muted);
}

.contact-info a {
  color: var(--ink);
  font-weight: 800;
}

.contact-form {
  display: grid;
  gap: 16px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: #fff;
  box-shadow: 0 24px 64px rgba(8, 28, 42, 0.1);
}

.contact-form label {
  display: grid;
  gap: 8px;
  color: #2b3a48;
  font-size: 14px;
  font-weight: 700;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #f8fbfc;
  padding: 14px 16px;
  color: var(--ink);
  font: inherit;
  outline: none;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: rgba(40, 214, 198, 0.82);
  box-shadow: 0 0 0 4px rgba(40, 214, 198, 0.16);
}

.contact-form textarea {
  resize: vertical;
}

.footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
  padding: 28px 0 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

@media (max-width: 980px) {
  .hero,
  .app-detail,
  .contact {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: 118px;
    gap: 28px;
  }

  .hero-copy {
    max-width: none;
  }

  .hero-visual {
    min-height: 600px;
  }

  .feature-grid,
  .news-list {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 720px) {
  .nav {
    width: min(100% - 28px, 1180px);
    height: 64px;
  }

  .brand-text {
    max-width: 140px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .nav-toggle {
    display: block;
  }

  .nav-menu {
    position: absolute;
    top: 64px;
    right: 14px;
    left: 14px;
    display: grid;
    gap: 4px;
    padding: 10px;
    border: 1px solid var(--line);
    border-radius: 22px;
    background: rgba(255, 255, 255, 0.96);
    box-shadow: 0 20px 58px rgba(8, 28, 42, 0.14);
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease, transform 0.2s ease;
  }

  .nav-menu.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav-menu a {
    min-height: 44px;
    border-radius: 14px;
    text-align: left;
  }

  .hero,
  .section {
    width: min(100% - 28px, 1180px);
  }

  .hero {
    min-height: auto;
    padding-bottom: 48px;
  }

  h1 {
    font-size: 42px;
  }

  .hero-desc {
    font-size: 17px;
  }

  .hero-visual {
    min-height: 530px;
    overflow: hidden;
  }

  .hero-visual::before {
    inset: 8% 0 8%;
    border-radius: 30px;
  }

  .phone-main {
    right: calc(50% - 165px);
    top: 18px;
    width: 218px;
    height: 456px;
  }

  .phone-side {
    left: calc(50% - 168px);
    bottom: 28px;
    width: 190px;
    height: 398px;
  }

  .calculator-display {
    height: 112px;
    font-size: 35px;
  }

  .calculator-grid {
    gap: 8px;
  }

  .product-strip,
  .feature-grid,
  .news-list {
    grid-template-columns: 1fr;
  }

  .metric {
    min-height: 130px;
  }

  .feature-card {
    min-height: 236px;
  }

  .feature-card h3 {
    margin-top: 44px;
  }

  .detail-line {
    min-height: auto;
    padding: 18px;
    align-items: flex-start;
    flex-direction: column;
  }

  .detail-line strong {
    text-align: left;
  }

  .contact-form {
    padding: 18px;
  }

  .footer {
    width: min(100% - 28px, 1180px);
    flex-direction: column;
  }
}

@media (max-width: 390px) {
  .brand-text {
    max-width: 112px;
  }

  h1 {
    font-size: 36px;
  }

  .hero-actions .btn {
    width: 100%;
  }

  .phone-main {
    right: calc(50% - 150px);
    width: 200px;
    height: 420px;
  }

  .phone-side {
    left: calc(50% - 142px);
    width: 168px;
    height: 354px;
  }

  .menu-screen {
    padding-inline: 16px;
  }

  .menu-screen h2 {
    font-size: 15px;
  }

  .menu-screen li {
    font-size: 13px;
  }
}