:root {
  --blue-900: #0a3a7a;
  --blue-700: #1565c0;
  --blue-500: #1e88e5;
  --blue-400: #42a5f5;
  --blue-100: #e3f2fd;
  --cyan: #00bcd4;
  --ink: #12263a;
  --muted: #5a6b7d;
  --line: #d7e3f0;
  --bg: #f4f8fc;
  --white: #ffffff;
  --radius: 14px;
  --shadow: 0 12px 36px rgba(21, 101, 192, 0.12);
  --max: 1120px;
  --font-display: "Sora", "Noto Sans SC", sans-serif;
  --font-body: "Noto Sans SC", "Sora", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(66, 165, 245, 0.22), transparent 60%),
    radial-gradient(900px 420px at 100% 0%, rgba(0, 188, 212, 0.16), transparent 55%),
    linear-gradient(180deg, #eef6ff 0%, var(--bg) 280px, #f7fafc 100%);
  min-height: 100vh;
}

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

a {
  color: var(--blue-700);
  text-decoration: none;
}

a:hover {
  color: var(--blue-500);
  text-decoration: underline;
}

.container {
  width: min(100% - 32px, var(--max));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
  background: rgba(255, 255, 255, 0.88);
  border-bottom: 1px solid rgba(215, 227, 240, 0.9);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 68px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
}

.brand img {
  width: 40px;
  height: 40px;
  border-radius: 10px;
}

.brand:hover {
  text-decoration: none;
  color: var(--blue-700);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px 18px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--ink);
  font-weight: 500;
  font-size: 0.95rem;
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--blue-700);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--blue-500), var(--blue-700));
  color: #fff !important;
  font-weight: 600;
  text-decoration: none !important;
  box-shadow: 0 8px 18px rgba(21, 101, 192, 0.28);
}

.menu-toggle {
  display: none;
  border: 1px solid var(--line);
  background: var(--white);
  border-radius: 10px;
  width: 42px;
  height: 42px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

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

.hero {
  padding: 48px 0 28px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 36px;
  align-items: center;
}

.hero-brand {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
}

.hero-brand img {
  width: 72px;
  height: 72px;
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.hero-brand h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3vw, 2.4rem);
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.hero-brand .sub {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.hero p.lead {
  margin: 0 0 22px;
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 36em;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 12px;
  font-weight: 700;
  text-decoration: none !important;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

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

.btn-primary {
  background: linear-gradient(135deg, var(--blue-400), var(--blue-700));
  color: #fff !important;
  box-shadow: 0 10px 24px rgba(21, 101, 192, 0.3);
}

.btn-secondary {
  background: var(--white);
  color: var(--blue-700) !important;
  border-color: var(--line);
}

.hero-note {
  color: var(--muted);
  font-size: 0.9rem;
}

.hero-visual {
  position: relative;
  border-radius: 24px;
  overflow: hidden;
  box-shadow: var(--shadow);
  background: linear-gradient(160deg, #dff1ff, #f8fbff);
  border: 1px solid rgba(255, 255, 255, 0.8);
  animation: floaty 5.5s ease-in-out infinite;
}

.hero-visual img {
  width: 100%;
  max-height: 560px;
  object-fit: cover;
  object-position: top;
}

@keyframes floaty {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.section {
  padding: 42px 0;
}

.section-head {
  margin-bottom: 22px;
}

.section-head h2 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 2.4vw, 1.9rem);
  letter-spacing: -0.01em;
}

.section-head p {
  margin: 0;
  color: var(--muted);
  max-width: 48em;
}

.panel {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 24px;
  box-shadow: 0 8px 24px rgba(18, 38, 58, 0.04);
}

.prose h2,
.prose h3 {
  font-family: var(--font-display);
  line-height: 1.35;
}

.prose h2 {
  margin: 1.6em 0 0.6em;
  font-size: 1.45rem;
}

.prose h3 {
  margin: 1.3em 0 0.5em;
  font-size: 1.15rem;
}

.prose p {
  margin: 0 0 1em;
  color: #243447;
}

.prose ul,
.prose ol {
  margin: 0 0 1.1em;
  padding-left: 1.25em;
}

.prose li {
  margin-bottom: 0.45em;
}

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

.feature-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.feature-card .shot {
  aspect-ratio: 9 / 16;
  max-height: 420px;
  overflow: hidden;
  background: #edf4fb;
}

.feature-card .shot img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
}

.feature-card .body {
  padding: 14px 16px 18px;
}

.feature-card h3 {
  margin: 0 0 6px;
  font-size: 1.05rem;
  font-family: var(--font-display);
}

.feature-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.login-grid {
  grid-template-columns: 0.9fr 1.1fr;
  align-items: center;
}

#login {
  scroll-margin-top: 160px;
}

.shot-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.shot-item {
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--white);
}

.shot-item img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
}

.shot-item figcaption {
  padding: 8px 10px 10px;
  font-size: 0.85rem;
  color: var(--muted);
  text-align: center;
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  counter-reset: step;
}

.step {
  position: relative;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 16px 16px;
}

.step::before {
  counter-increment: step;
  content: counter(step);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--cyan), var(--blue-500));
  color: #fff;
  font-weight: 700;
  font-size: 0.85rem;
  margin-bottom: 10px;
}

.step h3 {
  margin: 0 0 6px;
  font-size: 1rem;
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.toc {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.toc a {
  display: block;
  padding: 10px 12px;
  border-radius: 10px;
  background: var(--blue-100);
  color: var(--blue-900);
  font-weight: 600;
  text-decoration: none;
}

.toc a:hover {
  background: #d4ebff;
}

.faq details {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px 16px;
  margin-bottom: 10px;
}

.faq summary {
  cursor: pointer;
  font-weight: 700;
  color: var(--blue-900);
}

.faq details[open] summary {
  margin-bottom: 8px;
}

.faq p {
  margin: 0;
  color: var(--muted);
}

.related {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.related a {
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--white);
  border: 1px solid var(--line);
  color: var(--ink);
  text-decoration: none;
  font-size: 0.92rem;
}

.related a:hover {
  border-color: var(--blue-400);
  color: var(--blue-700);
}

.page-hero {
  padding: 36px 0 10px;
}

.page-hero h1 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.1rem);
}

.page-hero p {
  margin: 0;
  color: var(--muted);
}

.breadcrumb {
  margin-bottom: 12px;
  font-size: 0.9rem;
  color: var(--muted);
}

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

.site-footer {
  margin-top: 40px;
  padding: 28px 0 36px;
  background: linear-gradient(180deg, transparent, rgba(21, 101, 192, 0.06));
  border-top: 1px solid var(--line);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 24px;
}

.site-footer h3 {
  margin: 0 0 10px;
  font-size: 1rem;
  font-family: var(--font-display);
}

.site-footer p,
.site-footer li {
  color: var(--muted);
  font-size: 0.92rem;
}

.site-footer ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-footer li {
  margin-bottom: 6px;
}

.site-footer a {
  color: var(--muted);
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--blue-700);
}

.copyright {
  margin-top: 22px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.85rem;
  text-align: center;
}

.error-page {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 40px 0;
}

.error-page .code {
  font-family: var(--font-display);
  font-size: clamp(4rem, 12vw, 7rem);
  line-height: 1;
  background: linear-gradient(135deg, var(--blue-400), var(--blue-900));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin: 0;
  animation: pulse 2.4s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.82; transform: scale(0.98); }
}

.error-page h1 {
  margin: 8px 0 10px;
  font-family: var(--font-display);
}

.error-page p {
  margin: 0 0 20px;
  color: var(--muted);
}

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

  .steps,
  .shot-row {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 760px) {
  .menu-toggle {
    display: inline-flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px 16px 16px;
    background: rgba(255, 255, 255, 0.98);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 12px 24px rgba(18, 38, 58, 0.08);
  }

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

  .nav-links li a {
    display: block;
    padding: 12px 8px;
    border-bottom: 1px solid #eef3f8;
  }

  .nav-links .nav-cta {
    margin-top: 8px;
    text-align: center;
  }

  .hero-grid,
  .feature-grid,
  .footer-grid,
  .steps,
  .shot-row,
  .toc,
  .login-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: 28px;
  }

  .hero-visual {
    max-width: 360px;
    margin-inline: auto;
  }

  .feature-card .shot {
    max-height: 520px;
  }

  #login {
    scroll-margin-top: 180px;
    padding-top: 28px;
  }

  #login .section-head h2 {
    font-size: 1.28rem;
    line-height: 1.35;
  }

  #login .section-head p {
    font-size: 0.95rem;
  }

  #login .login-grid {
    gap: 14px;
  }

  #login .login-shot {
    max-width: 280px;
    margin-inline: auto;
    width: 100%;
  }

  #login .login-shot .shot {
    max-height: 420px;
    aspect-ratio: 9 / 16;
  }

  #login .login-shot .body {
    text-align: center;
    padding: 12px 14px 14px;
  }

  #login .login-copy {
    padding: 16px;
    font-size: 0.95rem;
    line-height: 1.7;
  }

  #login .login-copy p {
    margin-bottom: 0.85em;
  }

  #login .login-copy p:last-child {
    margin-bottom: 0;
  }
}