/* ============================================
   Quan105Labs — Global Stylesheet
   Tone: warm cream + orange + gold
   ============================================ */

:root {
  --cream-50: #FFFBF2;
  --cream-100: #FFF3DF;
  --cream-200: #FFE8C2;
  --orange-300: #FFB366;
  --orange-400: #FF8A3D;
  --orange-500: #E8621A;
  --orange-600: #C4571A;
  --gold-400: #FFC233;
  --gold-500: #FFA500;
  --coral: #FF9466;
  --ink-900: #2D1B0F;
  --ink-700: #5C3A1F;
  --ink-500: #8A6240;
  --white: #ffffff;
  
  --font-display: 'Plus Jakarta Sans', 'Helvetica Neue', system-ui, sans-serif;
  --font-body: 'Inter', 'Segoe UI', system-ui, sans-serif;
  
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 28px;
  --radius-xl: 40px;
  
  --shadow-sm: 0 2px 8px rgba(232, 98, 26, 0.08);
  --shadow-md: 0 8px 24px rgba(232, 98, 26, 0.12);
  --shadow-lg: 0 20px 48px rgba(232, 98, 26, 0.18);
  
  --max-width: 1200px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  background: var(--cream-50);
  color: var(--ink-900);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ========== NAV ========== */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 251, 242, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(232, 98, 26, 0.1);
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 18px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--ink-900);
  font-weight: 800;
  font-size: 20px;
  font-family: var(--font-display);
  letter-spacing: -0.3px;
}

.nav-brand img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

.nav-menu {
  display: flex;
  gap: 4px;
  align-items: center;
  list-style: none;
}

.nav-menu a {
  padding: 8px 16px;
  text-decoration: none;
  color: var(--ink-700);
  font-weight: 500;
  font-size: 15px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.nav-menu a:hover,
.nav-menu a.active {
  color: var(--orange-500);
  background: var(--cream-100);
}

.lang-toggle {
  display: inline-flex;
  background: var(--cream-100);
  border-radius: 100px;
  padding: 4px;
  gap: 2px;
}

.lang-btn {
  padding: 6px 14px;
  border: none;
  background: transparent;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-500);
  border-radius: 100px;
  cursor: pointer;
  transition: var(--transition);
  font-family: inherit;
}

.lang-btn.active {
  background: var(--white);
  color: var(--orange-500);
  box-shadow: var(--shadow-sm);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--ink-900);
}

/* ========== HERO ========== */
.hero {
  padding: 80px 32px 100px;
  background: 
    radial-gradient(circle at 10% 30%, rgba(255, 214, 107, 0.25) 0%, transparent 50%),
    radial-gradient(circle at 90% 70%, rgba(255, 179, 102, 0.25) 0%, transparent 50%),
    linear-gradient(180deg, var(--cream-50) 0%, var(--cream-100) 100%);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -100px;
  right: -100px;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255, 194, 51, 0.15) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-container {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 64px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--white);
  border: 1px solid var(--cream-200);
  padding: 8px 16px;
  border-radius: 100px;
  font-size: 13px;
  font-weight: 600;
  color: var(--orange-600);
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.hero-badge::before {
  content: '';
  width: 8px;
  height: 8px;
  background: var(--orange-400);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.3); }
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(40px, 6vw, 72px);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -2px;
  margin-bottom: 24px;
  color: var(--ink-900);
}

.hero h1 .highlight {
  background: linear-gradient(135deg, var(--orange-400) 0%, var(--gold-500) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 18px;
  color: var(--ink-700);
  margin-bottom: 36px;
  max-width: 520px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 15px;
  text-decoration: none;
  transition: var(--transition);
  cursor: pointer;
  border: none;
  font-family: inherit;
}

.btn-primary {
  background: linear-gradient(135deg, var(--orange-400) 0%, var(--orange-500) 100%);
  color: var(--white);
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: var(--white);
  color: var(--ink-900);
  border: 1px solid var(--cream-200);
}

.btn-secondary:hover {
  background: var(--cream-100);
  border-color: var(--orange-300);
}

.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
}

.hero-icon-wrap {
  position: relative;
  width: 320px;
  height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-icon-wrap img {
  width: 100%;
  height: 100%;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

.hero-shape {
  position: absolute;
  border-radius: var(--radius-md);
}

.hero-shape-1 {
  width: 80px; height: 80px;
  background: var(--gold-400);
  top: -20px; right: -30px;
  animation: float 5s ease-in-out infinite 0.5s;
}

.hero-shape-2 {
  width: 60px; height: 60px;
  background: var(--coral);
  bottom: 20px; left: -40px;
  border-radius: 50%;
  animation: float 4s ease-in-out infinite 1s;
}

.hero-shape-3 {
  width: 50px; height: 50px;
  background: var(--orange-300);
  bottom: -20px; right: 20px;
  border-radius: var(--radius-sm);
  transform: rotate(15deg);
  animation: float 5.5s ease-in-out infinite 1.5s;
}

/* ========== SECTIONS ========== */
.section {
  padding: 80px 32px;
}

.section-container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 56px;
}

.section-eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--orange-500);
  margin-bottom: 12px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 800;
  letter-spacing: -1.2px;
  line-height: 1.15;
  margin-bottom: 16px;
}

.section-subtitle {
  font-size: 17px;
  color: var(--ink-700);
  max-width: 620px;
  margin: 0 auto;
}

/* ========== CATEGORIES GRID ========== */
.categories {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.cat-card {
  background: var(--white);
  border: 1px solid #F5D9B3;
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(232, 98, 26, 0.06), 0 1px 2px rgba(232, 98, 26, 0.04);
}

.cat-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 0%, var(--cream-100) 100%);
  opacity: 0;
  transition: var(--transition);
}

.cat-card:hover {
  transform: translateY(-6px);
  border-color: var(--orange-300);
  box-shadow: var(--shadow-md);
}

.cat-card:hover::before {
  opacity: 0.4;
}

.cat-card > * {
  position: relative;
  z-index: 1;
}

.cat-icon {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  font-size: 28px;
}

.cat-icon.tools { background: linear-gradient(135deg, var(--orange-300) 0%, var(--orange-400) 100%); }
.cat-icon.games { background: linear-gradient(135deg, var(--gold-400) 0%, var(--gold-500) 100%); }
.cat-icon.edu { background: linear-gradient(135deg, var(--coral) 0%, var(--orange-500) 100%); }

.cat-card h3 {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: -0.3px;
}

.cat-card p {
  color: var(--ink-700);
  font-size: 15px;
  line-height: 1.6;
}

/* ========== APPS GRID ========== */
.apps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.app-card {
  background: var(--white);
  border: 1px solid #F5D9B3;
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  gap: 16px;
  transition: var(--transition);
  box-shadow: 0 1px 3px rgba(232, 98, 26, 0.06), 0 1px 2px rgba(232, 98, 26, 0.04);
}

.app-card:hover {
  transform: translateY(-4px);
  border-color: var(--orange-300);
  box-shadow: var(--shadow-md);
}

.app-card-icon {
  width: 72px;
  height: 72px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--cream-100) 0%, var(--cream-200) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 32px;
  overflow: hidden;
}

.app-card-icon--image {
  background: var(--white);
  border: 1px solid var(--cream-200);
  padding: 0;
}

.app-card-icon img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: inherit;
}

.app-card-body {
  display: flex;
  flex-direction: column;
  min-width: 0;
  flex: 1;
}

.app-card h3 {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 6px;
}

.app-card-subtitle {
  color: var(--ink-500);
  font-weight: 500;
  font-size: 14px;
  margin-left: 2px;
}

.app-card p {
  font-size: 13px;
  color: var(--ink-500);
  line-height: 1.5;
}

.app-card-meta {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-top: 10px;
}

.app-badge {
  display: inline-block;
  background: var(--cream-100);
  color: var(--orange-600);
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 100px;
  letter-spacing: 0.4px;
}

.app-badge-muted {
  background: transparent;
  color: var(--ink-500);
  border: 1px solid var(--cream-200);
}

.app-card-actions {
  display: flex;
  gap: 14px;
  align-items: center;
  flex-wrap: wrap;
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px dashed var(--cream-200);
}

.app-card-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--orange-500);
  text-decoration: none;
  transition: var(--transition);
}

.app-card-link:hover {
  color: var(--orange-600);
  transform: translateX(2px);
}

.app-card-link--secondary {
  color: var(--ink-500);
  font-weight: 500;
}

.app-card-link--secondary:hover {
  color: var(--ink-700);
}

.empty-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 80px 32px;
  background: var(--white);
  border: 2px dashed var(--cream-200);
  border-radius: var(--radius-lg);
}

.empty-state-emoji {
  font-size: 56px;
  margin-bottom: 16px;
  display: block;
}

.empty-state h3 {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 12px;
}

.empty-state p {
  color: var(--ink-700);
  max-width: 420px;
  margin: 0 auto;
}

/* ========== CONTENT PAGE (Privacy, Contact) ========== */
.content-page {
  padding: 60px 32px 80px;
}

.content-container {
  max-width: 800px;
  margin: 0 auto;
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 56px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--cream-200);
}

.content-container h1 {
  font-family: var(--font-display);
  font-size: 40px;
  font-weight: 800;
  letter-spacing: -1px;
  margin-bottom: 8px;
}

.content-meta {
  color: var(--ink-500);
  font-size: 14px;
  margin-bottom: 40px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--cream-100);
}

.content-container h2 {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 700;
  margin-top: 40px;
  margin-bottom: 16px;
  color: var(--ink-900);
}

.content-container h3 {
  font-size: 18px;
  font-weight: 700;
  margin-top: 24px;
  margin-bottom: 10px;
}

.content-container p,
.content-container li {
  color: var(--ink-700);
  font-size: 16px;
  line-height: 1.75;
  margin-bottom: 14px;
}

.content-container ul {
  padding-left: 24px;
  margin-bottom: 16px;
}

.content-container a:not(.contact-card) {
  color: var(--orange-500);
  text-decoration: none;
  font-weight: 600;
  border-bottom: 1px solid transparent;
  transition: var(--transition);
}

.content-container a:not(.contact-card):hover {
  border-bottom-color: var(--orange-500);
}

/* ========== CONTACT CARD ========== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
  margin-top: 40px;
}

.contact-card {
  background: var(--white);
  border: 1px solid #F5D9B3;
  border-radius: var(--radius-md);
  padding: 28px;
  text-decoration: none;
  color: var(--ink-900);
  transition: var(--transition);
  display: block;
  box-shadow: 0 1px 3px rgba(232, 98, 26, 0.06), 0 1px 2px rgba(232, 98, 26, 0.04);
}

.contact-card:hover {
  transform: translateY(-4px);
  border-color: var(--orange-300);
  box-shadow: var(--shadow-md);
}

.contact-card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  background: var(--cream-100);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  font-size: 22px;
}

.contact-card h3 {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 6px;
}

.contact-card p {
  font-size: 14px;
  color: var(--ink-500);
  margin: 0;
}

/* ========== FOOTER ========== */
.footer {
  margin-top: auto;
  background: var(--ink-900);
  color: var(--cream-100);
  padding: 56px 32px 32px;
}

.footer-container {
  max-width: var(--max-width);
  margin: 0 auto;
}

.footer-main {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 40px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 20px;
  color: var(--white);
}

.footer-brand img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

.footer-tagline {
  color: rgba(255, 243, 223, 0.6);
  font-size: 14px;
  line-height: 1.6;
  max-width: 320px;
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--gold-400);
  margin-bottom: 16px;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 10px;
}

.footer-col a {
  color: rgba(255, 243, 223, 0.7);
  text-decoration: none;
  font-size: 14px;
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--orange-400);
}

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid rgba(255, 243, 223, 0.1);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
  color: rgba(255, 243, 223, 0.5);
}

/* ========== LANGUAGE TOGGLE ========== */
/* Default: EN mode - hide .lang-vi */
body:not(.lang-vi) .lang-vi { display: none !important; }
/* VI mode - hide .lang-en */
body.lang-vi .lang-en { display: none !important; }

/* ========== RESPONSIVE ========== */
@media (max-width: 900px) {
  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 48px;
  }
  
  .hero-badge { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }
  .hero-subtitle { margin-left: auto; margin-right: auto; }
  .hero-icon-wrap { width: 240px; height: 240px; }
  
  .footer-main { grid-template-columns: 1fr; gap: 32px; }
  
  .content-container { padding: 36px 24px; }
  .content-container h1 { font-size: 32px; }
  
  .nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--white);
    padding: 16px;
    border-top: 1px solid var(--cream-200);
    box-shadow: var(--shadow-md);
    gap: 4px;
  }
  
  .nav-menu.open { display: flex; }
  .nav-menu a { padding: 12px 16px; width: 100%; }
  .nav-toggle { display: block; }
}

@media (max-width: 560px) {
  .nav-container { padding: 14px 20px; }
  .hero { padding: 48px 20px 72px; }
  .section { padding: 56px 20px; }
  .content-page { padding: 40px 16px 64px; }
  .content-container { padding: 28px 20px; }
  .footer { padding: 40px 20px 24px; }
}