:root {
  --bg: #0a1524;
  --bg-2: #0f1c30;
  --surface: #13233a;
  --surface-2: #18304c;
  --line: rgba(140, 180, 220, 0.16);
  --text: #eef4fb;
  --muted: #9eb0c7;
  --accent: #3aa7ff;
  --accent-2: #2fd6b2;
  --accent-soft: rgba(58, 167, 255, 0.14);
  --danger: #ff6b7a;
  --ok: #3dd6a5;
  --shadow: 0 18px 40px rgba(0, 0, 0, 0.35);
  --radius: 16px;
  --container: 1160px;
  --nav-h: 72px;
  --font-display: "Sora", "Be Vietnam Pro", sans-serif;
  --font-body: "Be Vietnam Pro", "Sora", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(58, 167, 255, 0.18), transparent 55%),
    radial-gradient(900px 500px at 90% 0%, rgba(47, 214, 178, 0.08), transparent 50%),
    linear-gradient(180deg, #08111d 0%, var(--bg) 40%, #081421 100%);
  min-height: 100vh;
  line-height: 1.65;
}

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

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

a:hover {
  color: #7bc7ff;
}

.container {
  width: min(100% - 2rem, var(--container));
  margin-inline: auto;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: rgba(8, 17, 29, 0.86);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: var(--nav-h);
}

.brand {
  display: inline-flex;
  align-items: center;
  height: 100%;
  flex-shrink: 0;
  max-width: min(168px, 40vw);
  overflow: hidden;
}

.brand img {
  height: 40px;
  width: auto;
  max-height: 40px;
  max-width: 100%;
  object-fit: contain;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  margin-left: auto;
}

.nav-desktop a {
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 500;
  padding: 0.55rem 0.75rem;
  border-radius: 10px;
}

.nav-desktop a:hover,
.nav-desktop a.active {
  color: var(--text);
  background: rgba(255, 255, 255, 0.04);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  margin-left: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  min-height: 42px;
  padding: 0.55rem 1.05rem;
  border-radius: 12px;
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.92rem;
  cursor: pointer;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: linear-gradient(135deg, #2f95ef, #45c2ff);
  color: #041018;
}

.btn-primary:hover {
  color: #041018;
}

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

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.menu-toggle {
  display: none;
  align-items: center;
  gap: 0.45rem;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--line);
  color: var(--text);
  border-radius: 12px;
  min-height: 42px;
  padding: 0.45rem 0.8rem;
  font-family: var(--font-body);
  font-weight: 600;
  cursor: pointer;
}

.menu-toggle svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

.mobile-panel {
  display: none;
  position: fixed;
  top: var(--nav-h);
  left: 0;
  right: 0;
  z-index: 999;
  background: rgba(8, 17, 29, 0.98);
  border-bottom: 1px solid var(--line);
  padding: 0.75rem 0 1.1rem;
  max-height: calc(100vh - var(--nav-h));
  overflow-y: auto;
}

.mobile-panel.open,
.mobile-panel:not([hidden]) {
  display: block;
  animation: slideDown 0.25s ease;
}

.mobile-panel[hidden] {
  display: none !important;
}

.mobile-panel a {
  display: block;
  color: var(--text);
  padding: 0.85rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  font-weight: 500;
}

.mobile-panel .mobile-actions {
  display: grid;
  gap: 0.65rem;
  margin-top: 1rem;
}

main {
  padding-top: var(--nav-h);
}

.hero {
  position: relative;
  min-height: calc(100vh - var(--nav-h));
  display: flex;
  align-items: flex-end;
  overflow: hidden;
  isolation: isolate;
}

.hero-media {
  position: absolute;
  inset: 0;
  z-index: -2;
}

.hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(90deg, rgba(6, 12, 22, 0.92) 0%, rgba(6, 12, 22, 0.72) 42%, rgba(6, 12, 22, 0.35) 100%),
    linear-gradient(180deg, rgba(6, 12, 22, 0.25) 0%, rgba(6, 12, 22, 0.88) 100%);
}

.hero-content {
  width: min(100% - 2rem, var(--container));
  margin: 0 auto 4.5rem;
  max-width: 680px;
  animation: fadeUp 0.7s ease both;
}

.brand-mark {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 6vw, 4.2rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.05;
  margin: 0 0 0.85rem;
  background: linear-gradient(180deg, #ffffff 20%, #9fd2ff 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero h1 {
  margin: 0 0 0.9rem;
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 2.4vw, 1.7rem);
  font-weight: 600;
  line-height: 1.35;
  color: var(--text);
}

.hero p {
  margin: 0 0 1.4rem;
  color: #c7d5e8;
  font-size: 1.02rem;
  max-width: 36rem;
}

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

.section {
  padding: 4.5rem 0;
}

.section-head {
  margin-bottom: 1.8rem;
  max-width: 40rem;
}

.section-head h2 {
  margin: 0 0 0.65rem;
  font-family: var(--font-display);
  font-size: clamp(1.45rem, 3vw, 2rem);
  letter-spacing: -0.02em;
}

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

.intro-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 2rem;
  align-items: center;
}

.intro-copy p {
  color: #c5d3e6;
  margin: 0 0 1rem;
}

.intro-visual {
  position: relative;
  border-radius: 24px;
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--line);
}

.intro-visual img {
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.category-item {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--surface);
  min-height: 180px;
  display: flex;
  align-items: flex-end;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.category-item:hover {
  transform: translateY(-4px);
  border-color: rgba(58, 167, 255, 0.45);
}

.category-item img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.78;
}

.category-item span {
  position: relative;
  z-index: 1;
  width: 100%;
  padding: 1rem;
  background: linear-gradient(180deg, transparent, rgba(4, 10, 18, 0.92));
  font-weight: 600;
  color: #fff;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.15rem;
}

.article-card {
  display: flex;
  flex-direction: column;
  background: linear-gradient(180deg, rgba(24, 42, 68, 0.75), rgba(14, 26, 44, 0.9));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: rgba(58, 167, 255, 0.4);
}

.article-card .thumb {
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: var(--surface-2);
}

.article-card .thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.article-card:hover .thumb img {
  transform: scale(1.04);
}

.article-card .body {
  padding: 1.05rem 1.1rem 1.2rem;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  flex: 1;
}

.article-card .tag {
  display: inline-flex;
  width: fit-content;
  font-size: 0.75rem;
  font-weight: 600;
  color: #8fd0ff;
  background: var(--accent-soft);
  padding: 0.22rem 0.55rem;
  border-radius: 999px;
}

.article-card h3 {
  margin: 0;
  font-size: 1.05rem;
  line-height: 1.4;
  font-family: var(--font-display);
}

.article-card h3 a {
  color: var(--text);
}

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

.article-card .meta {
  margin-top: auto;
  padding-top: 0.4rem;
  color: #7f93ad;
  font-size: 0.8rem;
}

.faq-list {
  display: grid;
  gap: 0.8rem;
}

.faq-item {
  background: rgba(19, 35, 58, 0.72);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1rem 1.1rem;
}

.faq-item h3 {
  margin: 0 0 0.45rem;
  font-size: 1rem;
  font-family: var(--font-display);
}

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

.brand-row {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 0.75rem;
  align-items: center;
}

.brand-row img {
  width: 100%;
  height: 48px;
  object-fit: contain;
  filter: grayscale(0.2) brightness(1.05);
  opacity: 0.9;
}

.page-hero {
  padding: 2.8rem 0 1.5rem;
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(58, 167, 255, 0.08), transparent);
}

.page-hero h1 {
  margin: 0 0 0.7rem;
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3.5vw, 2.4rem);
  letter-spacing: -0.02em;
}

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

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  align-items: center;
  margin-bottom: 1rem;
  color: var(--muted);
  font-size: 0.86rem;
}

.breadcrumb a {
  color: #9ec9ef;
}

.breadcrumb span {
  opacity: 0.55;
}

.content-wrap {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 1.75rem;
  padding: 2.5rem 0 4rem;
}

.prose {
  background: rgba(15, 28, 48, 0.55);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 1.5rem 1.4rem 1.8rem;
}

.prose h2 {
  margin: 1.8rem 0 0.7rem;
  font-family: var(--font-display);
  font-size: 1.35rem;
}

.prose h3 {
  margin: 1.35rem 0 0.55rem;
  font-family: var(--font-display);
  font-size: 1.1rem;
}

.prose p,
.prose li {
  color: #c6d4e7;
}

.prose ul,
.prose ol {
  padding-left: 1.2rem;
}

.prose img {
  border-radius: 14px;
  margin: 1rem 0;
  border: 1px solid var(--line);
}

.sidebar {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.side-box {
  background: rgba(15, 28, 48, 0.7);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1rem;
}

.side-box h2 {
  margin: 0 0 0.8rem;
  font-size: 1rem;
  font-family: var(--font-display);
}

.side-list {
  display: grid;
  gap: 0.75rem;
}

.side-list a {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 0.7rem;
  color: var(--text);
  align-items: center;
}

.side-list img {
  width: 72px;
  height: 52px;
  object-fit: cover;
  border-radius: 8px;
}

.side-list span {
  font-size: 0.88rem;
  line-height: 1.35;
}

.list-page {
  padding: 2.2rem 0 4rem;
}

.list-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-bottom: 1.4rem;
}

.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.4rem 0.8rem;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.86rem;
  background: rgba(255, 255, 255, 0.02);
}

.chip.active,
.chip:hover {
  color: var(--text);
  border-color: rgba(58, 167, 255, 0.45);
  background: var(--accent-soft);
}

.split-feature {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.2rem;
}

.feature-panel {
  border-radius: 18px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--surface);
  min-height: 260px;
  position: relative;
}

.feature-panel img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  min-height: 260px;
}

.feature-panel .caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 1.1rem;
  background: linear-gradient(180deg, transparent, rgba(4, 10, 18, 0.92));
}

.feature-panel h3 {
  margin: 0 0 0.35rem;
  font-family: var(--font-display);
}

.feature-panel p {
  margin: 0;
  color: #c5d3e6;
  font-size: 0.92rem;
}

.error-page {
  min-height: calc(100vh - var(--nav-h));
  display: grid;
  place-items: center;
  text-align: center;
  padding: 3rem 1rem;
}

.error-page h1 {
  margin: 0 0 0.6rem;
  font-size: clamp(3rem, 10vw, 5.5rem);
  font-family: var(--font-display);
  letter-spacing: -0.04em;
}

.error-page p {
  margin: 0 0 1.4rem;
  color: var(--muted);
  max-width: 28rem;
}

.site-footer {
  border-top: 1px solid var(--line);
  background: #070e18;
  padding: 3rem 0 1.5rem;
  margin-top: 1rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.site-footer h2,
.site-footer h3 {
  margin: 0 0 0.8rem;
  font-family: var(--font-display);
  font-size: 1rem;
}

.site-footer p,
.site-footer a {
  color: var(--muted);
}

.site-footer a {
  display: block;
  padding: 0.28rem 0;
}

.site-footer a:hover {
  color: #cfe6ff;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 1rem;
  color: #7f93ad;
  font-size: 0.86rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1rem;
  justify-content: space-between;
}

.ext-link {
  color: #8fd0ff;
  border-bottom: 1px dashed rgba(143, 208, 255, 0.45);
}

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

.guide-steps {
  display: grid;
  gap: 0.9rem;
}

.guide-step {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 0.9rem;
  align-items: start;
  padding: 1rem;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: rgba(19, 35, 58, 0.55);
}

.guide-step .num {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: var(--accent-soft);
  color: #9fd2ff;
  font-weight: 700;
  font-family: var(--font-display);
}

.guide-step h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
}

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

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 980px) {
  .nav-desktop,
  .nav-actions {
    display: none;
  }

  .menu-toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .intro-grid,
  .content-wrap,
  .split-feature,
  .footer-grid {
    grid-template-columns: 1fr;
  }

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

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

  .brand-row {
    grid-template-columns: repeat(4, 1fr);
  }

  .hero {
    min-height: 72vh;
  }

  .hero-content {
    margin-bottom: 2.8rem;
  }
}

@media (max-width: 640px) {
  :root {
    --nav-h: 64px;
  }

  .brand img {
    height: 36px;
  }

  .card-grid,
  .category-grid,
  .brand-row {
    grid-template-columns: 1fr 1fr;
  }

  .brand-row {
    grid-template-columns: repeat(4, 1fr);
  }

  .hero {
    min-height: 78vh;
  }

  .section {
    padding: 3.2rem 0;
  }

  .prose {
    padding: 1.15rem 1rem 1.4rem;
  }
}