/* ===== Reset & Base ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-bg: #0f1115;
  --color-bg-elevated: #161a21;
  --color-bg-card: #1c212b;
  --color-text: #e8eaed;
  --color-text-muted: #9aa0a8;
  --color-text-dim: #6b7280;
  --color-accent: #c9a66b;
  --color-accent-hover: #d4b57e;
  --color-border: #2a303c;
  --color-border-light: #363d4a;
  
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-serif: 'Playfair Display', Georgia, serif;
  
  --container: 1100px;
  --radius: 12px;
  --transition: 0.2s ease;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

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

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

ul, ol {
  list-style: none;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(15, 17, 21, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition);
}

.header.scrolled {
  border-bottom-color: var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
  color: var(--color-text);
}

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav a {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  transition: color var(--transition);
}

.nav a:hover {
  color: var(--color-text);
}

.nav-cta {
  padding: 8px 16px;
  border: 1px solid var(--color-border-light);
  border-radius: 8px;
  color: var(--color-text) !important;
}

.nav-cta:hover {
  border-color: var(--color-accent);
  color: var(--color-accent) !important;
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.menu-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--color-text);
}

/* ===== Hero ===== */
.hero {
  padding: 160px 0 100px;
  min-height: 90vh;
  display: flex;
  align-items: center;
}

.hero-label {
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 24px;
  font-weight: 500;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2.4rem, 5.5vw, 3.8rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 32px;
}

.hero-title span {
  color: var(--color-text-muted);
}

.hero-text {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  max-width: 620px;
  margin-bottom: 40px;
  line-height: 1.75;
}

.hero-text strong {
  color: var(--color-text);
  font-weight: 500;
}

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

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: 8px;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
}

.btn-primary {
  background: var(--color-accent);
  color: #0f1115;
}

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

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border-light);
}

.btn-secondary:hover {
  border-color: var(--color-text-muted);
}

.btn-large {
  padding: 16px 36px;
  font-size: 1rem;
}

/* ===== Sections ===== */
.section {
  padding: 100px 0;
}

.section-label {
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 16px;
  font-weight: 500;
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 600;
  line-height: 1.25;
  margin-bottom: 20px;
  letter-spacing: -0.01em;
}

.section-lead {
  font-size: 1.15rem;
  color: var(--color-text-muted);
  max-width: 560px;
  margin-bottom: 48px;
}

/* ===== Problem ===== */
.problem {
  background: var(--color-bg-elevated);
}

.problem-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
  margin-bottom: 56px;
}

.problem-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: border-color var(--transition);
}

.problem-card:hover {
  border-color: var(--color-border-light);
}

.problem-number {
  font-size: 0.8rem;
  color: var(--color-accent);
  margin-bottom: 12px;
  font-weight: 500;
}

.problem-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 10px;
}

.problem-card p {
  font-size: 0.92rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}

.problem-quote {
  max-width: 680px;
  margin: 0 auto;
  text-align: center;
}

.problem-quote blockquote {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  line-height: 1.5;
  color: var(--color-text);
  font-style: italic;
}

/* ===== COS ===== */
.cos-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.cos-lead {
  font-size: 1.25rem;
  color: var(--color-text);
  margin-bottom: 20px;
  font-weight: 500;
}

.cos-main p {
  color: var(--color-text-muted);
  margin-bottom: 16px;
  font-size: 1.05rem;
}

.cos-main strong {
  color: var(--color-text);
  font-weight: 500;
}

.cos-points {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.cos-point {
  padding-left: 20px;
  border-left: 2px solid var(--color-border-light);
}

.cos-point h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.cos-point p {
  font-size: 0.92rem;
  color: var(--color-text-muted);
}

/* ===== Scenarios ===== */
.scenarios {
  background: var(--color-bg-elevated);
}

.scenarios-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.scenario-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: border-color var(--transition), transform var(--transition);
}

.scenario-card:hover {
  border-color: var(--color-border-light);
  transform: translateY(-2px);
}

.scenario-industry {
  font-size: 0.8rem;
  color: var(--color-accent);
  margin-bottom: 14px;
  font-weight: 500;
  letter-spacing: 0.03em;
}

.scenario-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 12px;
  line-height: 1.35;
}

.scenario-card p {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  margin-bottom: 20px;
}

.scenario-link {
  font-size: 0.9rem;
  color: var(--color-text-dim);
  font-weight: 500;
}

/* ===== For whom ===== */
.whom-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

.whom-item {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  padding: 20px 24px;
  font-size: 0.98rem;
  color: var(--color-text-muted);
  transition: border-color var(--transition), color var(--transition);
}

.whom-item:hover {
  border-color: var(--color-border-light);
  color: var(--color-text);
}

/* ===== CTA ===== */
.cta {
  text-align: center;
  padding: 120px 0;
}

.cta-title {
  font-family: var(--font-serif);
  font-size: clamp(1.8rem, 3.5vw, 2.5rem);
  font-weight: 600;
  margin-bottom: 20px;
}

.cta-text {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  max-width: 480px;
  margin: 0 auto 36px;
  line-height: 1.7;
}

.cta-note {
  margin-top: 28px;
  font-size: 0.9rem;
  color: var(--color-text-dim);
}

/* ===== Footer ===== */
.footer {
  border-top: 1px solid var(--color-border);
  padding: 48px 0 40px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 24px;
}

.footer-brand .logo {
  margin-bottom: 4px;
}

.footer-brand p {
  font-size: 0.85rem;
  color: var(--color-text-dim);
}

.footer-links {
  display: flex;
  gap: 28px;
}

.footer-links a {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  transition: color var(--transition);
}

.footer-links a:hover {
  color: var(--color-text);
}

.footer-copy {
  text-align: right;
  font-size: 0.85rem;
  color: var(--color-text-dim);
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .cos-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  
  .footer-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .footer-links {
    justify-content: center;
  }
  
  .footer-copy {
    text-align: center;
  }
}

@media (max-width: 768px) {
  .nav {
    display: none;
  }
  
  .menu-toggle {
    display: flex;
  }
  
  .hero {
    padding: 120px 0 80px;
    min-height: auto;
  }
  
  .section {
    padding: 70px 0;
  }
  
  .cta {
    padding: 80px 0;
  }
  
  .hero-actions {
    flex-direction: column;
  }
  
  .btn {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 18px;
  }
  
  .problem-grid,
  .scenarios-grid,
  .whom-grid {
    grid-template-columns: 1fr;
  }
}