/* ===== Design tokens ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --font-sans: "Be Vietnam Pro", system-ui, -apple-system, sans-serif;

  --primary: #f0a500;
  --primary-hover: #d99200;
  --primary-soft: #fff8e7;
  --primary-muted: rgba(240, 165, 0, 0.14);

  --ink: #0f172a;
  --ink-secondary: #334155;
  --ink-muted: #64748b;
  --ink-faint: #94a3b8;

  --surface: #ffffff;
  --surface-alt: #f8fafc;
  --surface-elevated: #ffffff;

  --border: #e2e8f0;
  --border-strong: #cbd5e1;

  --accent: #b91c1c;
  --footer-bg: #0f172a;
  --footer-text: #cbd5e1;

  --shadow-xs: 0 1px 2px rgba(15, 23, 42, 0.05);
  --shadow-sm: 0 4px 16px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 12px 40px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 24px 64px rgba(15, 23, 42, 0.1);

  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 999px;

  --max-width: 1140px;
  --header-height: 72px;

  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.7;
  color: var(--ink-secondary);
  background: var(--surface);
}

a {
  color: inherit;
  text-decoration: none;
}

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

/* ===== Layout ===== */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 clamp(20px, 4vw, 32px);
}

/* ===== Header ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.8);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.125rem;
  letter-spacing: 0.04em;
  color: var(--ink);
  transition: opacity 0.2s var(--ease);
}

.logo:hover {
  opacity: 0.85;
}

.logo__icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--primary) 0%, #ffc94d 100%);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.75rem;
  letter-spacing: 0.02em;
  color: var(--ink);
  box-shadow: var(--shadow-xs);
}

.nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--ink-muted);
  padding: 8px 16px;
  border-radius: var(--radius-full);
  transition: color 0.2s var(--ease), background 0.2s var(--ease);
}

.nav a:hover {
  color: var(--ink);
  background: var(--surface-alt);
}

/* ===== Hero ===== */
.hero {
  position: relative;
  overflow: hidden;
  padding: clamp(64px, 10vw, 112px) 0 clamp(72px, 10vw, 96px);
  background:
    radial-gradient(ellipse 80% 60% at 100% 0%, var(--primary-muted) 0%, transparent 60%),
    radial-gradient(ellipse 50% 40% at 0% 100%, rgba(248, 250, 252, 1) 0%, transparent 70%),
    linear-gradient(180deg, var(--primary-soft) 0%, var(--surface) 45%);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: 0.35;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.4), transparent 80%);
  pointer-events: none;
}

.hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: clamp(32px, 6vw, 64px);
  align-items: center;
}

.hero__content {
  max-width: 580px;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--primary-hover);
  background: var(--surface);
  border: 1px solid rgba(240, 165, 0, 0.25);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  margin-bottom: 24px;
  box-shadow: var(--shadow-xs);
}

.hero__badge::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--primary);
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin-bottom: 20px;
}

.hero h1 span {
  display: block;
  background: linear-gradient(135deg, var(--primary-hover) 0%, #f5c842 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-top: 4px;
}

.hero__subtitle {
  font-size: clamp(1rem, 2vw, 1.125rem);
  color: var(--ink-muted);
  line-height: 1.75;
  margin-bottom: 32px;
  max-width: 520px;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero__aside {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.hero__panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: clamp(24px, 4vw, 32px);
  box-shadow: var(--shadow-md);
}

.hero__panel-label {
  display: block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 8px;
}

.hero__panel-value {
  display: block;
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin-bottom: 4px;
}

.hero__panel-desc {
  font-size: 0.9375rem;
  color: var(--ink-muted);
}

.hero__highlights {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.hero__highlight {
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 16px;
}

.hero__highlight strong {
  display: block;
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 2px;
}

.hero__highlight span {
  font-size: 0.8125rem;
  color: var(--ink-muted);
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.9375rem;
  padding: 14px 28px;
  border-radius: var(--radius-full);
  border: none;
  cursor: pointer;
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease), background 0.2s var(--ease);
}

.btn--primary {
  background: var(--ink);
  color: var(--surface);
  box-shadow: var(--shadow-sm);
}

.btn--primary:hover {
  background: #1e293b;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn--ghost {
  background: var(--surface);
  color: var(--ink);
  border: 1px solid var(--border-strong);
}

.btn--ghost:hover {
  border-color: var(--ink-faint);
  background: var(--surface-alt);
}

.btn--outline {
  background: transparent;
  color: var(--ink);
  border: 1.5px solid var(--border-strong);
}

.btn--outline:hover {
  border-color: var(--primary);
  background: var(--primary-soft);
}

/* ===== Sections ===== */
.section {
  padding: clamp(64px, 10vw, 96px) 0;
}

.section--alt {
  background: var(--surface-alt);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.section__header {
  text-align: center;
  margin-bottom: clamp(40px, 6vw, 56px);
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
}

.section__label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--primary-hover);
  margin-bottom: 12px;
}

.section__header h2 {
  font-size: clamp(1.625rem, 3.5vw, 2.25rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.25;
  color: var(--ink);
  margin-bottom: 16px;
}

.section__header p {
  font-size: 1.0625rem;
  color: var(--ink-muted);
  line-height: 1.75;
}

/* ===== Intro cards ===== */
.intro-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 32px;
}

.intro-card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), border-color 0.25s var(--ease);
}

.intro-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(240, 165, 0, 0.3);
}

.intro-card__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--primary-hover);
  background: var(--primary-soft);
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
}

.intro-card h3 {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

.intro-card p {
  font-size: 0.9375rem;
  color: var(--ink-muted);
  line-height: 1.7;
}

.about-banner {
  display: flex;
  gap: clamp(24px, 4vw, 48px);
  align-items: center;
  justify-content: space-between;
  background: var(--ink);
  color: var(--footer-text);
  border-radius: var(--radius-lg);
  padding: clamp(28px, 5vw, 40px);
  box-shadow: var(--shadow-lg);
}

.about-banner__content h3 {
  font-size: clamp(1.125rem, 2vw, 1.375rem);
  font-weight: 600;
  color: var(--surface);
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.about-banner__content p {
  font-size: 0.9375rem;
  color: var(--ink-faint);
  line-height: 1.75;
  max-width: 600px;
}

.about-banner__tag {
  flex-shrink: 0;
  text-align: right;
  padding-left: 24px;
  border-left: 1px solid rgba(255, 255, 255, 0.12);
}

.about-banner__tag strong {
  display: block;
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--surface);
  margin-bottom: 6px;
}

.about-banner__tag span {
  font-size: 0.8125rem;
  color: var(--ink-faint);
}

/* ===== Program cards ===== */
.programs-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.program-card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 24px 32px;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
  overflow: hidden;
}

.program-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), #ffc94d);
  opacity: 0;
  transition: opacity 0.25s var(--ease);
}

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

.program-card:hover::before {
  opacity: 1;
}

.program-card__icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-soft);
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
  color: var(--primary-hover);
}

.program-card__icon svg {
  width: 22px;
  height: 22px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.program-card h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.program-card p {
  font-size: 0.875rem;
  color: var(--ink-muted);
  line-height: 1.65;
}

/* ===== Benefits ===== */
.benefits-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  max-width: 880px;
  margin: 0 auto;
}

.benefit-item {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  padding: 28px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: box-shadow 0.25s var(--ease);
}

.benefit-item:hover {
  box-shadow: var(--shadow-sm);
}

.benefit-item__mark {
  width: 28px;
  height: 28px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 2px;
}

.benefit-item__mark svg {
  width: 14px;
  height: 14px;
  stroke: var(--ink);
  fill: none;
  stroke-width: 2.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.benefit-item h4 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 6px;
}

.benefit-item p {
  font-size: 0.9375rem;
  color: var(--ink-muted);
  line-height: 1.65;
}

.benefit-item strong {
  color: var(--ink);
  font-weight: 600;
}

/* ===== Contact ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  align-items: stretch;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.contact-item {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
}

.contact-item__icon {
  width: 48px;
  height: 48px;
  background: var(--primary-soft);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: var(--primary-hover);
}

.contact-item__icon svg {
  width: 22px;
  height: 22px;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.contact-item h4 {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 6px;
}

.contact-item p {
  font-size: 0.9375rem;
  color: var(--ink-secondary);
  line-height: 1.6;
}

.contact-item p.highlight {
  color: var(--accent);
  font-weight: 500;
}

.contact-box {
  background: linear-gradient(160deg, var(--ink) 0%, #1e293b 100%);
  border-radius: var(--radius-lg);
  padding: clamp(28px, 4vw, 40px);
  color: var(--footer-text);
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.contact-box h3 {
  font-size: clamp(1.125rem, 2vw, 1.375rem);
  font-weight: 600;
  color: var(--surface);
  margin-bottom: 14px;
  letter-spacing: -0.01em;
}

.contact-box p {
  font-size: 0.9375rem;
  color: var(--ink-faint);
  line-height: 1.75;
}

.contact-box .btn {
  margin-top: 24px;
  align-self: flex-start;
}

/* ===== Footer ===== */
.footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: clamp(48px, 8vw, 64px) 0 28px;
}

.footer__inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 40px;
  margin-bottom: 40px;
}

.footer__brand .logo {
  color: var(--surface);
  margin-bottom: 14px;
}

.footer__brand p {
  font-size: 0.9375rem;
  color: var(--ink-faint);
  max-width: 300px;
  line-height: 1.65;
}

.footer__links {
  display: flex;
  gap: clamp(32px, 6vw, 72px);
}

.footer__links h4 {
  color: var(--surface);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.footer__links ul {
  list-style: none;
}

.footer__links li {
  margin-bottom: 10px;
  font-size: 0.9375rem;
  color: var(--ink-faint);
}

.footer__links a {
  transition: color 0.2s var(--ease);
}

.footer__links a:hover {
  color: var(--primary);
}

.footer__bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 24px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  font-size: 0.8125rem;
  color: #64748b;
}

/* ===== 404 ===== */
.page-404 {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.page-404__main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 48px 24px;
  background:
    radial-gradient(ellipse 60% 50% at 50% 0%, var(--primary-muted) 0%, transparent 70%),
    var(--surface-alt);
}

.page-404__content {
  text-align: center;
  max-width: 440px;
}

.page-404__code {
  font-size: clamp(5rem, 18vw, 7.5rem);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.04em;
  background: linear-gradient(135deg, var(--primary-hover), #ffc94d);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 12px;
}

.page-404__title {
  font-size: clamp(1.25rem, 3vw, 1.5rem);
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.page-404__desc {
  color: var(--ink-muted);
  margin-bottom: 32px;
  font-size: 0.9375rem;
  line-height: 1.7;
}

.page-404__actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

/* ===== Responsive ===== */
@media (max-width: 960px) {
  .programs-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .hero__inner {
    grid-template-columns: 1fr;
  }

  .hero__aside {
    order: -1;
  }

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

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

  .about-banner {
    flex-direction: column;
    text-align: center;
  }

  .about-banner__tag {
    text-align: center;
    padding-left: 0;
    border-left: none;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.12);
    width: 100%;
  }

  .programs-grid,
  .benefits-grid,
  .contact-grid {
    grid-template-columns: 1fr;
  }

  .footer__links {
    gap: 32px;
  }
}

@media (max-width: 480px) {
  .nav {
    gap: 0;
  }

  .nav a {
    padding: 8px 10px;
    font-size: 0.875rem;
  }

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

  .hero__actions {
    flex-direction: column;
  }

  .hero__actions .btn {
    width: 100%;
  }
}