/**
 * Premium CSS — File Tiếng Trung
 * Clean, professional styling. No excessive gradients or glow.
 */

/* Fonts */
@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800&family=Be+Vietnam+Pro:wght@400;500;600;700;800&display=swap');

/* Variables */
:root {
  --primary: #06d6a0;
  --primary-light: #34e8b8;
  --primary-dark: #04b686;
  --primary-rgb: 6, 214, 160;

  --accent: #ffd166;
  --accent-light: #ffe08a;
  --accent-dark: #e6b84d;
  --accent-rgb: 255, 209, 102;

  --success: #06d6a0;
  --success-light: #34e8b8;
  --warning: #ffd166;
  --error: #ff6b6b;

  --text: #1a1d26;
  --text-light: #333;
  --text-secondary: #5a6178;
  --text-muted: #8b92a8;

  --bg: #f8f9fc;
  --bg-soft: #ffffff;
  --bg-muted: #f0f2f7;
  --bg-dark: #0a0e1a;
  --bg-card: #fff;

  --border: rgba(0, 0, 0, 0.08);
  --border-light: rgba(0, 0, 0, 0.04);

  --shadow-xs: 0 1px 2px rgba(0, 0, 0, .04);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, .06);
  --shadow: 0 2px 8px rgba(0, 0, 0, .06);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, .08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, .1);
  --shadow-xl: 0 12px 36px rgba(0, 0, 0, .12);

  --gradient-primary: linear-gradient(135deg, #06d6a0, #38bdf8);
  --gradient-accent: linear-gradient(135deg, #ffd166, #ff6b6b);
  --gradient-dark: linear-gradient(180deg, #0a0e1a, #111827);
  --gradient-hero: linear-gradient(180deg, #f8f9fc 0%, #fff 100%);

  --font-main: 'Outfit', 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  --transition-fast: .15s ease;
  --transition: .2s ease;
  --transition-slow: .3s ease;

  --radius-sm: 6px;
  --radius: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-2xl: 20px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-main);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-main);
  font-weight: 700;
  line-height: 1.3;
  color: var(--text);
}

.text-gradient {
  background: linear-gradient(135deg, #06d6a0, #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Container */
.container {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 24px;
}

.container-narrow {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Glass — subtle, not neon */
.glass {
  background: rgba(255, 255, 255, .85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, .2);
}

.glass-dark {
  background: rgba(17, 24, 39, .85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, .06);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border-radius: var(--radius);
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 600;
  font-family: var(--font-main);
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
}

.btn-primary {
  background: var(--primary);
  color: #0a0e1a;
  box-shadow: 0 1px 3px rgba(6, 214, 160, .2);
}

.btn-primary:hover {
  background: var(--primary-light);
  box-shadow: 0 2px 6px rgba(6, 214, 160, .3);
  transform: translateY(-1px);
}

.btn-accent {
  background: var(--accent);
  color: #fff;
}

.btn-accent:hover {
  background: var(--accent-dark);
}

.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 1px solid var(--primary);
}

.btn-outline:hover {
  background: var(--primary);
  color: #fff;
}

.btn-white {
  background: #fff;
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.btn-white:hover {
  box-shadow: var(--shadow);
}

.btn-lg {
  padding: 14px 28px;
  font-size: 15px;
  border-radius: var(--radius-lg);
}

.btn-sm {
  padding: 8px 16px;
  font-size: 13px;
}

.btn-icon {
  padding: 10px;
  border-radius: var(--radius);
}

/* Cards */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: box-shadow var(--transition), border-color var(--transition);
}

.card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--border);
}

.card-premium {
  background: var(--bg);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

.card-premium::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--primary);
}

/* Sections */
.section {
  padding: 64px 0;
  position: relative;
}

.section-sm {
  padding: 40px 0;
}

.section-lg {
  padding: 80px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(6, 214, 160, .08);
  color: var(--primary);
  padding: 6px 14px;
  border-radius: 100px;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .06em;
  margin-bottom: 16px;
}

.section-title {
  font-size: 26px;
  font-weight: 700;
  margin-bottom: 10px;
  letter-spacing: -.02em;
  line-height: 1.25;
}

.section-desc {
  font-size: 15px;
  color: var(--text-secondary);
  max-width: 520px;
  margin: 0 auto;
  line-height: 1.6;
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, .96);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  transition: box-shadow var(--transition);
}

.header.scrolled {
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: var(--primary);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
}

.logo-text {
  font-size: 20px;
  font-weight: 800;
  color: var(--primary);
}

.nav ul {
  display: flex;
  gap: 4px;
  list-style: none;
}

.nav a {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius);
  transition: all var(--transition);
}

.nav a:hover {
  color: var(--primary);
  background: var(--bg-muted);
}

.nav a.active {
  color: var(--primary);
  background: rgba(37, 99, 235, .06);
}

.header-actions {
  display: flex;
  gap: 10px;
  align-items: center;
}

/* Hero */
.hero {
  padding: 110px 0 60px;
  background: var(--bg-soft);
  position: relative;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(37, 99, 235, .06);
  padding: 8px 16px;
  border-radius: 100px;
  margin-bottom: 20px;
}

.hero-badge-dot {
  width: 8px;
  height: 8px;
  background: var(--primary);
  border-radius: 50%;
}

.hero-badge span {
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
}

.hero-title {
  font-size: 36px;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 16px;
  letter-spacing: -.02em;
}

.hero-title span {
  color: var(--primary);
  -webkit-text-fill-color: var(--primary);
  background: none;
}

.hero-subtitle {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 24px;
  line-height: 1.6;
}

.hero-cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}

.hero-stats {
  display: flex;
  gap: 32px;
}

.hero-stat {
  text-align: left;
}

.hero-stat-value {
  font-size: 28px;
  font-weight: 800;
  color: var(--primary);
}

.hero-stat-label {
  font-size: 13px;
  color: var(--text-secondary);
  margin-top: 2px;
}

/* Form Card */
.form-card {
  background: var(--bg);
  border-radius: var(--radius-xl);
  padding: 28px;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  position: relative;
}

.form-card::before {
  display: none;
}

.form-header {
  text-align: center;
  margin-bottom: 28px;
}

.form-header-icon {
  width: 48px;
  height: 48px;
  background: var(--primary);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 14px;
  color: #fff;
}

.form-header h3 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 6px;
}

.form-header p {
  font-size: 14px;
  color: var(--text-secondary);
}

.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}

.form-label .required {
  color: var(--error);
}

.form-input {
  width: 100%;
  padding: 10px 14px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  font-size: 14px;
  font-family: var(--font-main);
  transition: border-color var(--transition);
  background: var(--bg);
}

.form-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 2px rgba(6, 214, 160, .12);
}

.form-input::placeholder {
  color: var(--text-muted);
}

.form-input.code-input {
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 18px;
  font-weight: 600;
  letter-spacing: .12em;
  text-transform: uppercase;
  text-align: center;
}

/* Feature Cards */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--bg);
  border-radius: var(--radius-lg);
  padding: 24px;
  border: 1px solid var(--border);
  transition: box-shadow var(--transition);
}

.feature-card:hover {
  box-shadow: var(--shadow-md);
}

.feature-icon {
  width: 42px;
  height: 42px;
  background: rgba(6, 214, 160, .08);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 14px;
  color: var(--primary);
}

.feature-card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 6px;
}

.feature-card p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Product Cards */
.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.product-card {
  background: var(--bg);
  border-radius: var(--radius-xl);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: box-shadow var(--transition), border-color var(--transition);
  display: flex;
  flex-direction: column;
}

.product-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
  transform: translateY(-2px);
}

.product-card.popular {
  border-color: var(--primary);
  position: relative;
}

.product-card.popular::before {
  content: 'Phổ biến nhất';
  position: absolute;
  top: 12px;
  right: 12px;
  background: var(--primary);
  color: #fff;
  padding: 4px 12px;
  border-radius: 100px;
  font-size: 11px;
  font-weight: 600;
  z-index: 10;
}

.product-image {
  height: 160px;
  background: var(--bg-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: 24px;
}

.product-image img {
  width: auto;
  height: 64px;
  max-width: 64px;
  object-fit: contain;
  border-radius: 8px;
  transition: transform var(--transition);
}

.product-card:hover .product-image img {
  transform: scale(1.05);
}

.product-image svg {
  width: 56px;
  height: 56px;
  transition: transform var(--transition);
}

.product-card:hover .product-image svg {
  transform: scale(1.04);
}

.product-content {
  padding: 24px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.product-content h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 6px;
}

.product-content>p {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 16px;
}

.product-features {
  list-style: none;
  margin-bottom: 20px;
  flex: 1;
}

.product-features li {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-light);
  padding: 6px 0;
}

.product-features li svg {
  color: var(--success);
  flex-shrink: 0;
}

.product-price {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 16px;
}

.product-price .current {
  font-size: 28px;
  font-weight: 800;
  color: var(--primary);
}

.product-price .original {
  font-size: 16px;
  color: var(--text-muted);
  text-decoration: line-through;
}

/* Support Section */
.support-card {
  background: var(--primary);
  border-radius: var(--radius-xl);
  padding: 48px;
  text-align: center;
  color: #fff;
  position: relative;
}

.support-card h2 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 12px;
  color: #fff;
  position: relative;
  z-index: 1;
}

.support-card>p {
  font-size: 16px;
  opacity: .9;
  margin-bottom: 28px;
  position: relative;
  z-index: 1;
}

.support-buttons {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}

/* Footer */
footer {
  background: var(--bg-dark);
  color: #fff;
  padding-top: 64px;
  border-top: 1px solid rgba(255, 255, 255, .06);
}

body.dark-mode footer {
  border-top-color: rgba(255, 255, 255, .1);
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 48px;
}

body.dark-mode .footer-top {
  border-bottom: 1px solid rgba(255, 255, 255, .08);
}

.footer-brand {
  max-width: 300px;
}

.footer-brand .logo {
  margin-bottom: 16px;
}

.footer-brand .logo-icon {
  background: var(--primary);
}

.footer-brand .logo-text {
  color: #fff;
  background: none;
  -webkit-text-fill-color: #fff;
}

.footer-brand p {
  color: rgba(255, 255, 255, .6);
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 20px;
}

.footer-social {
  display: flex;
  gap: 8px;
}

.footer-social a {
  width: 36px;
  height: 36px;
  background: rgba(255, 255, 255, .08);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255, 255, 255, .7);
  transition: all var(--transition);
}

.footer-social a:hover {
  background: var(--primary);
  color: #fff;
}

.footer-col h4 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 20px;
  color: #fff;
}

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

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

.footer-col a {
  color: rgba(255, 255, 255, .6);
  text-decoration: none;
  font-size: 14px;
  transition: color var(--transition);
}

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

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
}

.footer-bottom span,
.footer-bottom a {
  color: rgba(255, 255, 255, .4);
  font-size: 13px;
  text-decoration: none;
}

.footer-bottom a:hover {
  color: rgba(255, 255, 255, .8);
}

/* Page Layout */
.page-hero {
  padding: 140px 0 64px;
  background: var(--bg-soft);
  text-align: center;
}

.page-hero h1 {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 12px;
}

.page-hero p {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

.page-breadcrumb {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  margin-bottom: 20px;
  font-size: 13px;
  color: var(--text-secondary);
}

.page-breadcrumb a {
  color: var(--primary);
  text-decoration: none;
}

.page-breadcrumb a:hover {
  text-decoration: underline;
}

.page-content {
  padding: 64px 0;
}

.content-card {
  background: var(--bg);
  border-radius: var(--radius-xl);
  padding: 40px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
}

.content-card h2 {
  font-size: 24px;
  margin-bottom: 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
}

.content-card h3 {
  font-size: 20px;
  margin: 28px 0 14px;
  color: var(--primary);
}

.content-card p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-light);
  margin-bottom: 14px;
}

.content-card ul,
.content-card ol {
  margin: 14px 0;
  padding-left: 20px;
}

.content-card li {
  margin-bottom: 10px;
  line-height: 1.6;
  color: var(--text-light);
}

/* FAQ */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: var(--bg);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  overflow: hidden;
}

.faq-item:hover {
  border-color: var(--primary);
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-main);
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  text-align: left;
  transition: background var(--transition);
}

.faq-question:hover {
  background: var(--bg-soft);
}

.faq-question svg {
  flex-shrink: 0;
  transition: transform var(--transition);
  color: var(--primary);
}

.faq-item.active .faq-question svg {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition);
}

.faq-item.active .faq-answer {
  max-height: 500px;
}

.faq-answer-inner {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* Animations — minimal, professional */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

.animate-fadeInUp {
  animation: fadeInUp .4s ease forwards;
}

.animate-fadeIn {
  animation: fadeIn .4s ease forwards;
}

.delay-100 {
  animation-delay: .1s;
}

.delay-200 {
  animation-delay: .2s;
}

.delay-300 {
  animation-delay: .3s;
}

.delay-400 {
  animation-delay: .4s;
}

.delay-500 {
  animation-delay: .5s;
}

/* Utilities */
.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

.text-right {
  text-align: right;
}

.mt-1 {
  margin-top: 8px
}

.mt-2 {
  margin-top: 16px
}

.mt-3 {
  margin-top: 24px
}

.mt-4 {
  margin-top: 32px
}

.mt-5 {
  margin-top: 48px
}

.mb-1 {
  margin-bottom: 8px
}

.mb-2 {
  margin-bottom: 16px
}

.mb-3 {
  margin-bottom: 24px
}

.mb-4 {
  margin-bottom: 32px
}

.mb-5 {
  margin-bottom: 48px
}

.py-1 {
  padding-top: 8px;
  padding-bottom: 8px
}

.py-2 {
  padding-top: 16px;
  padding-bottom: 16px
}

.py-3 {
  padding-top: 24px;
  padding-bottom: 24px
}

.py-4 {
  padding-top: 32px;
  padding-bottom: 32px
}

.py-5 {
  padding-top: 48px;
  padding-bottom: 48px
}

/* Responsive */
@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero-title {
    font-size: 32px;
  }

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

  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }

  .section {
    padding: 48px 0;
  }

  .section-title {
    font-size: 24px;
  }

  .hero {
    padding: 100px 0 48px;
  }

  .hero-title {
    font-size: 28px;
  }

  .hero-subtitle {
    font-size: 15px;
  }

  .hero-stats {
    gap: 20px;
  }

  .hero-stat-value {
    font-size: 22px;
  }

  .features-grid,
  .products-grid {
    grid-template-columns: 1fr;
  }

  .header-inner nav {
    display: none;
  }

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

  .footer-bottom {
    flex-direction: column;
    gap: 10px;
    text-align: center;
  }

  .support-card {
    padding: 32px 20px;
  }

  .support-buttons {
    flex-direction: column;
  }

  .form-card {
    padding: 24px;
  }

  .content-card {
    padding: 24px;
  }

  .page-hero h1 {
    font-size: 28px;
  }
}

/* Scrollbar */
::-webkit-scrollbar {
  display: none;
}

* {
  scrollbar-width: none;
  -ms-overflow-style: none;
}

/* Selection */
::selection {
  background: var(--primary);
  color: #fff;
}