/* 小蓝Blued 官网 - xl-app.quest */
:root {
  --blue-900: #0a2a4a;
  --blue-800: #0e3d6b;
  --blue-700: #155a9a;
  --blue-600: #1a7cc4;
  --blue-500: #2b9fe0;
  --blue-400: #5bb8ea;
  --blue-100: #e8f4fc;
  --blue-50: #f3f9fd;
  --ink: #142033;
  --ink-soft: #3d4f66;
  --muted: #6b7c90;
  --line: #d5e4f0;
  --surface: #ffffff;
  --accent: #00a8e8;
  --warm: #ff8a3d;
  --radius: 14px;
  --shadow: 0 12px 40px rgba(14, 61, 107, 0.12);
  --max: 1120px;
  --font-display: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(43, 159, 224, 0.18), transparent 60%),
    radial-gradient(900px 500px at 100% 0%, rgba(0, 168, 232, 0.12), transparent 55%),
    linear-gradient(180deg, #f7fbfe 0%, #eef5fb 40%, #f8fafc 100%);
  line-height: 1.75;
  font-size: 16px;
}

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% - 2rem, var(--max));
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(247, 251, 254, 0.88);
  border-bottom: 1px solid rgba(213, 228, 240, 0.8);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--blue-900);
  text-decoration: none;
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  object-fit: cover;
}

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

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.1rem;
  align-items: center;
}

.nav a {
  color: var(--ink-soft);
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
}

.nav a:hover,
.nav a.active {
  color: var(--blue-600);
}

.nav-cta {
  background: linear-gradient(135deg, var(--blue-600), var(--accent));
  color: #fff !important;
  padding: 0.45rem 0.95rem;
  border-radius: 999px;
  box-shadow: 0 6px 18px rgba(26, 124, 196, 0.35);
}

.nav-cta:hover {
  text-decoration: none;
  filter: brightness(1.05);
}

.menu-toggle {
  display: none;
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 10px;
  width: 42px;
  height: 42px;
  padding: 0;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  color: var(--blue-800);
  cursor: pointer;
  flex-shrink: 0;
  position: relative;
  z-index: 2;
}

.menu-toggle-bar {
  display: block;
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.menu-toggle[aria-expanded="true"] .menu-toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .menu-toggle-bar:nth-child(2) {
  opacity: 0;
}

.menu-toggle[aria-expanded="true"] .menu-toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  padding: 3.5rem 0 2.5rem;
  min-height: min(88vh, 760px);
  display: flex;
  align-items: center;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(115deg, rgba(10, 42, 74, 0.94) 0%, rgba(21, 90, 154, 0.82) 48%, rgba(0, 168, 232, 0.55) 100%),
    radial-gradient(800px 400px at 20% 30%, rgba(91, 184, 234, 0.35), transparent 70%),
    radial-gradient(600px 360px at 90% 70%, rgba(255, 138, 61, 0.18), transparent 65%),
    linear-gradient(160deg, #0a2a4a, #155a9a 55%, #1a7cc4);
  z-index: 0;
  animation: heroShift 18s ease-in-out infinite alternate;
}

@keyframes heroShift {
  from { transform: scale(1); }
  to { transform: scale(1.06); }
}

.hero-inner {
  position: relative;
  z-index: 1;
  color: #fff;
  max-width: 720px;
  animation: fadeUp 0.9s ease both;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(22px); }
  to { opacity: 1; transform: translateY(0); }
}

.hero-brand {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  margin-bottom: 1.25rem;
}

.hero-brand img {
  width: 72px;
  height: 72px;
  border-radius: 18px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

.hero-brand span {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 900;
  letter-spacing: 0.04em;
  line-height: 1.15;
  text-shadow: 0 4px 24px rgba(0, 0, 0, 0.25);
}

.hero h1 {
  margin: 0 0 0.85rem;
  font-size: clamp(1.35rem, 3vw, 1.85rem);
  font-weight: 700;
  line-height: 1.4;
}

.hero p {
  margin: 0 0 1.5rem;
  font-size: 1.05rem;
  opacity: 0.95;
  max-width: 38rem;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.85rem 1.35rem;
  border-radius: 999px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  text-decoration: none;
  transform: translateY(-2px);
}

.btn-primary {
  background: #fff;
  color: var(--blue-800);
  box-shadow: 0 10px 28px rgba(0, 0, 0, 0.2);
}

.btn-primary:hover {
  color: var(--blue-600);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.45);
  backdrop-filter: blur(6px);
}

.btn-ghost:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.22);
}

.btn-solid {
  background: linear-gradient(135deg, var(--blue-600), var(--accent));
  color: #fff;
  box-shadow: 0 8px 22px rgba(26, 124, 196, 0.3);
}

.btn-solid:hover {
  color: #fff;
}

/* Sections */
.section {
  padding: 3.25rem 0;
}

.section-alt {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.7), rgba(232, 244, 252, 0.55));
}

.section-head {
  margin-bottom: 1.75rem;
  max-width: 48rem;
}

.section-head h2 {
  margin: 0 0 0.55rem;
  font-size: clamp(1.45rem, 2.6vw, 1.9rem);
  color: var(--blue-900);
  line-height: 1.3;
}

.section-head p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 1.02rem;
}

.lead {
  font-size: 1.08rem;
  color: var(--ink-soft);
}

.prose p {
  margin: 0 0 1rem;
  color: var(--ink-soft);
}

.prose h2,
.prose h3 {
  color: var(--blue-900);
  margin: 1.75rem 0 0.75rem;
  line-height: 1.35;
}

.prose h2 {
  font-size: 1.45rem;
}

.prose h3 {
  font-size: 1.18rem;
}

.prose ul,
.prose ol {
  margin: 0 0 1.1rem;
  padding-left: 1.25rem;
  color: var(--ink-soft);
}

.prose li {
  margin-bottom: 0.4rem;
}

.toc {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.1rem 1.25rem;
  margin: 1.25rem 0 2rem;
  box-shadow: var(--shadow);
}

.toc strong {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--blue-900);
}

.toc ol {
  margin: 0;
  padding-left: 1.2rem;
  columns: 2;
  gap: 1.5rem;
}

.toc a {
  font-weight: 600;
}

/* Feature showcase */
.feature-block {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 2rem;
  align-items: center;
  margin: 2.25rem 0;
}

.feature-block.reverse {
  grid-template-columns: 0.95fr 1.05fr;
}

.feature-block.reverse .feature-media {
  order: 2;
}

.feature-media {
  position: relative;
}

.feature-media img {
  width: 100%;
  border-radius: 18px;
  box-shadow: var(--shadow);
  border: 1px solid rgba(255, 255, 255, 0.6);
  animation: softFloat 5.5s ease-in-out infinite;
}

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

.feature-copy h3 {
  margin: 0 0 0.6rem;
  font-size: 1.35rem;
  color: var(--blue-900);
}

.feature-copy p {
  margin: 0 0 0.85rem;
  color: var(--ink-soft);
}

.feature-copy ul {
  margin: 0;
  padding-left: 1.15rem;
  color: var(--ink-soft);
}

.shot-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-top: 1.5rem;
}

.shot-grid figure {
  margin: 0;
}

.shot-grid img {
  width: 100%;
  border-radius: 14px;
  box-shadow: 0 8px 24px rgba(14, 61, 107, 0.1);
  border: 1px solid var(--line);
  aspect-ratio: 9/16;
  object-fit: cover;
  object-position: top;
}

.shot-grid figcaption {
  margin-top: 0.45rem;
  font-size: 0.88rem;
  color: var(--muted);
  text-align: center;
}

.steps {
  counter-reset: step;
  display: grid;
  gap: 1rem;
  margin: 1.5rem 0;
}

.step {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.15rem 1.25rem 1.15rem 4rem;
  position: relative;
  box-shadow: 0 6px 20px rgba(14, 61, 107, 0.06);
}

.step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 1rem;
  top: 1.15rem;
  width: 2.1rem;
  height: 2.1rem;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--blue-600), var(--accent));
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 800;
}

.step h3 {
  margin: 0 0 0.35rem;
  font-size: 1.08rem;
  color: var(--blue-900);
}

.step p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.98rem;
}

.faq details {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.85rem 1.1rem;
  margin-bottom: 0.7rem;
}

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

.faq details p {
  margin: 0.65rem 0 0.2rem;
  color: var(--ink-soft);
}

.inline-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin: 1rem 0;
}

.chip {
  display: inline-block;
  padding: 0.35rem 0.8rem;
  border-radius: 999px;
  background: var(--blue-100);
  color: var(--blue-800);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
}

.chip:hover {
  background: var(--blue-500);
  color: #fff;
  text-decoration: none;
}

.download-panel {
  background: linear-gradient(135deg, var(--blue-800), var(--blue-600) 55%, var(--accent));
  color: #fff;
  border-radius: 20px;
  padding: 2rem;
  box-shadow: var(--shadow);
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 1.5rem;
  align-items: center;
}

.download-panel h2 {
  margin: 0 0 0.6rem;
  font-size: 1.6rem;
}

.download-panel p {
  margin: 0 0 1rem;
  opacity: 0.95;
}

.download-panel img {
  border-radius: 16px;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
  max-height: 360px;
  margin-inline: auto;
  object-fit: contain;
}

/* Page hero (inner pages) */
.page-hero {
  padding: 2.4rem 0 1.5rem;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(232, 244, 252, 0.9), transparent);
}

.page-hero h1 {
  margin: 0 0 0.5rem;
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  color: var(--blue-900);
}

.page-hero p {
  margin: 0;
  color: var(--ink-soft);
  max-width: 42rem;
}

.breadcrumbs {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

.breadcrumbs a {
  color: var(--blue-700);
}

.content-wrap {
  padding: 2.2rem 0 3.5rem;
}

/* Error pages */
.error-page {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 3rem 1rem;
}

.error-page h1 {
  font-size: clamp(2.5rem, 8vw, 4.5rem);
  margin: 0;
  color: var(--blue-700);
}

.error-page p {
  color: var(--ink-soft);
  max-width: 28rem;
  margin: 0.85rem auto 1.4rem;
}

/* Footer */
.site-footer {
  background: var(--blue-900);
  color: rgba(255, 255, 255, 0.86);
  padding: 2.5rem 0 1.5rem;
  margin-top: 1rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 1.75rem;
  margin-bottom: 1.75rem;
}

.site-footer h3 {
  margin: 0 0 0.7rem;
  color: #fff;
  font-size: 1.05rem;
}

.site-footer p,
.site-footer a {
  color: rgba(255, 255, 255, 0.78);
  font-size: 0.95rem;
}

.site-footer a:hover {
  color: #fff;
}

.footer-links {
  display: grid;
  gap: 0.4rem;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin-bottom: 0.75rem;
}

.footer-brand img {
  width: 44px;
  height: 44px;
  border-radius: 10px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 1rem;
  font-size: 0.88rem;
  color: rgba(255, 255, 255, 0.6);
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  justify-content: space-between;
}

/* Utilities */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.note {
  background: #fff8f0;
  border-left: 4px solid var(--warm);
  padding: 0.85rem 1rem;
  border-radius: 0 10px 10px 0;
  color: var(--ink-soft);
  margin: 1rem 0;
}

@media (max-width: 900px) {
  .menu-toggle {
    display: inline-flex;
  }

  .nav-wrap {
    position: relative;
    flex-wrap: nowrap;
  }

  .nav {
    display: none;
    position: absolute;
    top: calc(100% + 1px);
    left: 0;
    right: 0;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.65rem 0.85rem 0.85rem;
    background: rgba(247, 251, 254, 0.98);
    border: 1px solid var(--line);
    border-radius: 12px;
    box-shadow: 0 12px 28px rgba(14, 61, 107, 0.12);
    z-index: 120;
  }

  .nav.open {
    display: flex;
  }

  .nav a {
    padding: 0.7rem 0.55rem;
    border-bottom: 1px solid rgba(213, 228, 240, 0.7);
  }

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

  .nav .nav-cta {
    margin-top: 0.35rem;
    text-align: center;
  }

  .feature-block,
  .feature-block.reverse {
    grid-template-columns: 1fr;
  }

  .feature-block.reverse .feature-media {
    order: 0;
  }

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

  .toc ol {
    columns: 1;
  }

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

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

  .hero {
    min-height: auto;
    padding: 2.5rem 0 2rem;
  }
}

@media (max-width: 560px) {
  .shot-grid {
    grid-template-columns: 1fr 1fr;
    gap: 0.65rem;
  }

  .hero-brand img {
    width: 56px;
    height: 56px;
  }

  body {
    font-size: 15px;
  }
}