/* KGame – k-game-app.lol | Portal đánh bài online */
:root {
  --bg: #0b1220;
  --bg-2: #121a2b;
  --bg-3: #182235;
  --surface: #1a2438;
  --line: rgba(120, 160, 220, 0.16);
  --text: #e8eef8;
  --muted: #9aabc4;
  --accent: #3b9eff;
  --accent-2: #66b8ff;
  --gold: #d4a84b;
  --danger: #e85d5d;
  --ok: #3ecf8e;
  --radius: 14px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --header-h: 72px;
  --max: 1180px;
  --font: "Sora", "Be Vietnam Pro", sans-serif;
  --display: "Outfit", "Sora", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 80% -10%, rgba(59, 158, 255, 0.18), transparent 55%),
    radial-gradient(900px 500px at -10% 20%, rgba(212, 168, 75, 0.08), transparent 50%),
    linear-gradient(180deg, #08101c 0%, var(--bg) 40%, #0a101c 100%);
  background-attachment: fixed;
  line-height: 1.65;
  min-height: 100vh;
}

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

a {
  color: var(--accent-2);
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

a:hover {
  color: #fff;
}

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

h1, h2, h3, h4 {
  font-family: var(--display);
  line-height: 1.25;
  font-weight: 700;
  margin: 0 0 0.75rem;
}

p {
  margin: 0 0 1rem;
  color: var(--muted);
}

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

/* Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: rgba(8, 14, 26, 0.82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

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

.logo-link {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  position: relative;
  z-index: 2;
}

.logo-link img {
  height: 48px;
  width: auto;
  max-height: calc(var(--header-h) - 16px);
  object-fit: contain;
  filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.35));
}

.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 0.8rem;
  border-radius: 999px;
}

.nav-desktop a:hover,
.nav-desktop a.active {
  color: #fff;
  background: rgba(59, 158, 255, 0.12);
}

.auth-desktop {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  margin-left: 0.6rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.7rem 1.15rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.92rem;
  border: 1px solid transparent;
  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, #2f8ef0, #56b4ff);
  color: #061018;
}

.btn-primary:hover {
  color: #061018;
}

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

.btn-ghost:hover {
  border-color: var(--accent);
  color: #fff;
}

.menu-toggle {
  display: none;
  align-items: center;
  gap: 0.45rem;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  border-radius: 999px;
  padding: 0.45rem 0.85rem;
  cursor: pointer;
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 600;
}

.menu-toggle svg {
  width: 20px;
  height: 20px;
  stroke: currentColor;
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.nav-mobile {
  display: none;
  position: fixed;
  top: var(--header-h);
  left: 0;
  right: 0;
  background: rgba(10, 16, 28, 0.97);
  border-bottom: 1px solid var(--line);
  padding: 1rem;
  z-index: 999;
  transform: translateY(-8px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

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

.nav-mobile a {
  display: block;
  padding: 0.85rem 1rem;
  color: var(--muted);
  border-radius: 10px;
  font-weight: 500;
}

.nav-mobile a:hover,
.nav-mobile a.active {
  background: rgba(59, 158, 255, 0.1);
  color: #fff;
}

.nav-mobile .auth-mobile {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.6rem;
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--line);
}

/* Main offset */
main {
  padding-top: calc(var(--header-h) + 0.5rem);
}

/* Hero */
.hero {
  position: relative;
  min-height: min(78vh, 680px);
  display: flex;
  align-items: flex-end;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(8, 14, 26, 0.25) 0%, rgba(8, 14, 26, 0.55) 45%, rgba(8, 14, 26, 0.96) 100%),
    url("banner.3dd2.webp") center / cover no-repeat;
  transform: scale(1.02);
  animation: heroZoom 18s ease-in-out infinite alternate;
}

@keyframes heroZoom {
  from { transform: scale(1.02); }
  to { transform: scale(1.08); }
}

.hero-content {
  position: relative;
  z-index: 1;
  padding: 3.5rem 0 3rem;
  max-width: 720px;
  animation: fadeUp 0.8s ease both;
}

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

.hero-brand {
  font-family: var(--display);
  font-size: clamp(2.4rem, 6vw, 3.8rem);
  letter-spacing: -0.03em;
  margin-bottom: 0.4rem;
  background: linear-gradient(90deg, #fff, #9fd0ff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero h1 {
  font-size: clamp(1.35rem, 3.2vw, 1.85rem);
  font-weight: 650;
  margin-bottom: 0.9rem;
  color: #fff;
}

.hero p {
  font-size: 1.05rem;
  max-width: 560px;
  margin-bottom: 1.4rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}

/* Sections */
.section {
  padding: 3.5rem 0;
}

.section-head {
  margin-bottom: 1.75rem;
  max-width: 720px;
}

.section-head h2 {
  font-size: clamp(1.45rem, 3vw, 1.9rem);
}

.section-head p {
  margin-bottom: 0;
}

.eyebrow {
  display: inline-block;
  color: var(--accent-2);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 0.45rem;
}

/* Intro / prose */
.prose {
  max-width: 760px;
}

.prose a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

.intro-visual {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  animation: floatSoft 5s ease-in-out infinite;
}

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

.intro-visual img {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
}

/* Category grid */
.cat-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.cat-card {
  position: relative;
  display: block;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg-3);
  min-height: 180px;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.cat-card:hover {
  transform: translateY(-4px);
  border-color: rgba(59, 158, 255, 0.45);
}

.cat-card img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  background: #000;
}

.cat-card span {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 0.85rem 1rem;
  background: linear-gradient(transparent, rgba(0, 0, 0, 0.85));
  color: #fff;
  font-weight: 650;
  font-size: 0.95rem;
}

/* Cards / articles */
.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(26, 36, 56, 0.9), rgba(18, 26, 43, 0.95));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  height: 100%;
}

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

.article-card .thumb {
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: #000;
}

.article-card .thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.45s ease;
}

.article-card:hover .thumb img {
  transform: scale(1.05);
}

.article-card .body {
  padding: 1.1rem 1.15rem 1.25rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.article-card .meta {
  font-size: 0.78rem;
  color: var(--accent-2);
  font-weight: 600;
  margin-bottom: 0.45rem;
}

.article-card h3 {
  font-size: 1.05rem;
  margin-bottom: 0.55rem;
}

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

.article-card h3 a:hover {
  color: var(--accent-2);
}

.article-card p {
  font-size: 0.92rem;
  flex: 1;
  margin-bottom: 0.9rem;
}

.article-card .more {
  font-size: 0.88rem;
  font-weight: 650;
  color: var(--accent);
}

/* Brand strip */
.brand-strip {
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  gap: 0.75rem;
  align-items: center;
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(18, 26, 43, 0.7);
}

.brand-strip img {
  width: 100%;
  height: 42px;
  object-fit: contain;
  opacity: 0.85;
  filter: grayscale(0.2);
  transition: opacity 0.2s ease, filter 0.2s ease;
}

.brand-strip img:hover {
  opacity: 1;
  filter: none;
}

/* FAQ */
.faq-list {
  display: grid;
  gap: 0.75rem;
  max-width: 860px;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(18, 26, 43, 0.75);
  overflow: hidden;
}

.faq-item summary {
  cursor: pointer;
  list-style: none;
  padding: 1rem 1.15rem;
  font-weight: 650;
  color: #fff;
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  color: var(--accent-2);
  font-size: 1.2rem;
  line-height: 1;
}

.faq-item[open] summary::after {
  content: "–";
}

.faq-item .faq-body {
  padding: 0 1.15rem 1.1rem;
  color: var(--muted);
}

/* Page hero (inner) */
.page-hero {
  padding: 2.5rem 0 1.5rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 0.5rem;
  background:
    linear-gradient(90deg, rgba(59, 158, 255, 0.08), transparent 60%);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 0.85rem;
}

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

.breadcrumb a:hover {
  color: var(--accent-2);
}

.breadcrumb span {
  opacity: 0.5;
}

.page-hero h1 {
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  margin-bottom: 0.55rem;
}

/* Article detail */
.article-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 2rem;
  align-items: start;
  padding: 2rem 0 3.5rem;
}

.article-cover {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  margin-bottom: 1.5rem;
  background: #000;
}

.article-cover img {
  width: 100%;
  max-height: 420px;
  object-fit: cover;
}

.article-body h2 {
  margin-top: 1.8rem;
  font-size: 1.35rem;
}

.article-body h3 {
  margin-top: 1.35rem;
  font-size: 1.1rem;
}

.article-body li {
  color: var(--muted);
  margin-bottom: 0.35rem;
}

.sidebar {
  position: sticky;
  top: calc(var(--header-h) + 1rem);
  display: grid;
  gap: 1rem;
}

.side-box {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(18, 26, 43, 0.85);
  padding: 1.1rem;
}

.side-box h3 {
  font-size: 1rem;
  margin-bottom: 0.85rem;
}

.side-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.7rem;
}

.side-list a {
  color: var(--muted);
  font-size: 0.9rem;
  display: block;
  line-height: 1.4;
}

.side-list a:hover {
  color: var(--accent-2);
}

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

/* Category page blocks */
.cat-detail {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 1.25rem;
  align-items: center;
  padding: 1.25rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(18, 26, 43, 0.7);
  margin-bottom: 1rem;
}

.cat-detail img {
  width: 160px;
  height: 160px;
  object-fit: cover;
  border-radius: 12px;
  background: #000;
}

/* Legal / about */
.content-narrow {
  max-width: 820px;
  padding: 2rem 0 3.5rem;
}

.content-narrow h2 {
  margin-top: 1.8rem;
  font-size: 1.25rem;
}

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

.error-page .code {
  font-family: var(--display);
  font-size: clamp(4rem, 12vw, 7rem);
  line-height: 1;
  background: linear-gradient(135deg, var(--accent), #fff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 0.5rem;
}

.error-page h1 {
  margin-bottom: 0.6rem;
}

.error-actions {
  display: flex;
  gap: 0.7rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 1.4rem;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--line);
  background: #070c16;
  padding: 3rem 0 1.5rem;
  margin-top: 2rem;
}

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

.footer-brand img {
  height: 52px;
  width: auto;
  margin-bottom: 0.85rem;
}

.footer-brand p {
  font-size: 0.92rem;
}

.footer-col h4 {
  font-size: 0.95rem;
  margin-bottom: 0.85rem;
  color: #fff;
}

.footer-col a {
  display: block;
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.footer-col a:hover {
  color: var(--accent-2);
}

.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 1.1rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem;
  color: var(--muted);
  font-size: 0.85rem;
}

/* Promo band */
.promo-band {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 1.5rem;
  align-items: center;
  padding: 1.5rem;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background:
    linear-gradient(120deg, rgba(59, 158, 255, 0.12), rgba(212, 168, 75, 0.08));
}

.promo-band img {
  width: 100%;
  max-height: 220px;
  object-fit: contain;
}

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

/* Responsive */
@media (max-width: 1024px) {
  .cat-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

  .intro-grid,
  .article-layout,
  .promo-band,
  .footer-grid {
    grid-template-columns: 1fr;
  }

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

  .sidebar {
    position: static;
  }
}

@media (max-width: 768px) {
  :root {
    --header-h: 64px;
  }

  .nav-desktop,
  .auth-desktop {
    display: none;
  }

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

  .nav-mobile {
    display: block;
  }

  .logo-link img {
    height: 40px;
  }

  .hero {
    min-height: 62vh;
  }

  .card-grid,
  .related-grid,
  .cat-grid {
    grid-template-columns: 1fr;
  }

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

  .cat-detail {
    grid-template-columns: 1fr;
  }

  .cat-detail img {
    width: 100%;
    height: auto;
    max-height: 220px;
  }

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

@media (max-width: 480px) {
  .brand-strip {
    grid-template-columns: repeat(2, 1fr);
  }

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