/* ========================================
   Kith OS — Shared Styles
   Brand: Kith AI Lab visual system, amber accent
   ======================================== */

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

:root {
  /* Backgrounds */
  --color-base: #1a1d21;
  --color-surface: #1e2227;
  --color-card: #232629;

  /* Borders */
  --color-border: rgba(232, 230, 227, 0.06);
  --color-border-hover: rgba(212, 165, 116, 0.25);

  /* Text */
  --color-text-primary: #e8e6e3;
  --color-text-secondary: rgba(232, 230, 227, 0.5);
  --color-text-tertiary: rgba(232, 230, 227, 0.35);
  --color-text-muted: rgba(232, 230, 227, 0.25);

  /* Accent */
  --color-amber: #D4A574;
  --color-amber-bright: #E5B885;
  --color-amber-glow: rgba(212, 165, 116, 0.5);
  --color-amber-subtle: rgba(212, 165, 116, 0.08);

  /* Typography */
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'Berkeley Mono', ui-monospace, monospace;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: linear-gradient(145deg, #1a1d21 0%, #1e2227 50%, #1a1d21 100%);
  color: var(--color-text-secondary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

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

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

/* ========================================
   Navigation
   ======================================== */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 0 48px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(26, 29, 33, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
}

.nav-wordmark {
  height: 22px;
  width: auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-text-tertiary);
  letter-spacing: 0.01em;
  transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-text-primary);
}

.nav-cta {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-base) !important;
  background: var(--color-amber);
  padding: 8px 20px;
  border-radius: 6px;
  transition: box-shadow 0.3s ease;
}

.nav-cta:hover {
  box-shadow: 0 0 20px rgba(212, 165, 116, 0.4);
  color: var(--color-base) !important;
}

/* Mobile nav */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-text-secondary);
  margin: 5px 0;
  transition: all 0.3s ease;
}

/* ========================================
   Layout
   ======================================== */

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 32px;
}

.container--wide {
  max-width: 1120px;
}

section {
  padding: 88px 0;
}

section + section {
  border-top: 1px solid rgba(232, 230, 227, 0.10);
}

/* ========================================
   Hero
   ======================================== */

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 100px 32px 72px;
  border-bottom: none;
}

.hero + section {
  border-top: none;
}

.hero-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-amber);
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(32px, 5vw, 56px);
  font-weight: 600;
  color: var(--color-text-primary);
  line-height: 1.15;
  letter-spacing: -0.025em;
  max-width: 720px;
  margin: 0 auto 24px;
}

.hero p {
  font-size: clamp(16px, 1.8vw, 18px);
  color: var(--color-text-secondary);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.65;
}

/* ========================================
   Buttons
   ======================================== */

.btn-primary {
  display: inline-block;
  background: var(--color-amber);
  color: var(--color-base);
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  padding: 14px 32px;
  border-radius: 6px;
  border: none;
  cursor: pointer;
  transition: box-shadow 0.3s ease;
}

.btn-primary:hover {
  box-shadow: 0 0 24px rgba(212, 165, 116, 0.4);
}

.btn-ghost {
  display: inline-block;
  color: var(--color-text-secondary);
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  padding: 14px 32px;
  border-radius: 6px;
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-ghost:hover {
  border-color: var(--color-border-hover);
  color: var(--color-text-primary);
}

/* ========================================
   Section Headers
   ======================================== */

.section-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-amber);
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(24px, 3.5vw, 36px);
  font-weight: 600;
  color: var(--color-text-primary);
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.section-subtitle {
  font-size: 16px;
  color: var(--color-text-secondary);
  max-width: 600px;
  line-height: 1.65;
}

/* ========================================
   Product Slideshow
   ======================================== */

.slideshow {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 32px 88px;
}

.slideshow-window {
  position: relative;
  border-radius: 10px;
  overflow: hidden;
  border: 1px solid rgba(232, 230, 227, 0.10);
  box-shadow:
    0 4px 24px rgba(0, 0, 0, 0.4),
    0 0 64px rgba(212, 165, 116, 0.06);
  background: var(--color-surface);
  aspect-ratio: 16 / 10;
}

.slideshow-dots {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  z-index: 2;
  display: flex;
  gap: 6px;
  padding: 10px 14px;
  background: linear-gradient(180deg, rgba(26, 29, 33, 0.9) 0%, transparent 100%);
}

.slideshow-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.slideshow-dots span:nth-child(1) { background: #ff5f57; }
.slideshow-dots span:nth-child(2) { background: #febc2e; }
.slideshow-dots span:nth-child(3) { background: #28c840; }

.slideshow-track {
  position: absolute;
  inset: 0;
}


.slideshow-track img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top left;
  opacity: 0;
  animation: slideshow-fade 25s infinite;
}

.slideshow-track img:nth-child(1) { animation-delay: 0s; opacity: 1; }
.slideshow-track img:nth-child(2) { animation-delay: 5s; }
.slideshow-track img:nth-child(3) { animation-delay: 10s; }
.slideshow-track img:nth-child(4) { animation-delay: 15s; }
.slideshow-track img:nth-child(5) { animation-delay: 20s; }

@keyframes slideshow-fade {
  0%    { opacity: 0; }
  2%    { opacity: 1; }
  18%   { opacity: 1; }
  22%   { opacity: 0; }
  100%  { opacity: 0; }
}

.slideshow-label {
  text-align: center;
  margin-top: 20px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
}

@media (max-width: 768px) {
  .slideshow {
    padding: 0 24px 64px;
  }

  .slideshow-window {
    border-radius: 8px;
  }

  .slideshow-dots span {
    width: 8px;
    height: 8px;
  }

  .slideshow-dots {
    padding: 8px 12px;
    gap: 5px;
  }
}

/* ========================================
   Section Divider (internal pivot)
   ======================================== */

.section-divider {
  width: 48px;
  height: 1px;
  background: var(--color-amber);
  opacity: 0.3;
  margin: 56px 0;
}

/* ========================================
   Cards / Feature Grid
   ======================================== */

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.card {
  background: linear-gradient(135deg, rgba(232, 230, 227, 0.03) 0%, rgba(232, 230, 227, 0.01) 100%);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 32px;
  transition: all 0.3s ease;
}

.card:hover {
  background: linear-gradient(135deg, rgba(232, 230, 227, 0.06) 0%, rgba(212, 165, 116, 0.08) 100%);
  border-color: var(--color-border-hover);
  box-shadow: inset 0 0 40px rgba(212, 165, 116, 0.06), 0 0 20px rgba(212, 165, 116, 0.03);
}

.card-number {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-amber);
  letter-spacing: 0.1em;
  margin-bottom: 16px;
}

.card h3 {
  font-size: 16px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

.card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

/* ========================================
   Contrast Block (Problem/Solution)
   ======================================== */

.contrast-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

.contrast-block--problem h3,
.contrast-block--solution h3 {
  font-size: 20px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 12px;
  letter-spacing: -0.01em;
}

.contrast-block--problem p,
.contrast-block--solution p {
  font-size: 15px;
  line-height: 1.7;
}

.contrast-block--problem p {
  color: var(--color-text-tertiary);
}

.contrast-block--solution p {
  color: var(--color-text-secondary);
}

/* ========================================
   Compound Section (highlight)
   ======================================== */

.highlight-section {
  text-align: center;
  padding: 104px 32px;
  background: linear-gradient(180deg, rgba(212, 165, 116, 0.04) 0%, rgba(212, 165, 116, 0.02) 100%);
  border-top: 1px solid rgba(212, 165, 116, 0.12) !important;
  border-bottom: 1px solid rgba(212, 165, 116, 0.12);
}

.highlight-section .section-title {
  max-width: 640px;
  margin: 0 auto 16px;
}

.highlight-section .section-subtitle {
  max-width: 520px;
  margin: 0 auto;
}

/* ========================================
   CTA Section
   ======================================== */

.cta-section {
  text-align: center;
  padding: 104px 32px;
  background: linear-gradient(180deg, transparent 0%, rgba(212, 165, 116, 0.03) 50%, transparent 100%);
}

.cta-section .section-title {
  margin-bottom: 24px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.cta-section .section-subtitle {
  margin: 0 auto 48px;
}

.cta-section .btn-primary {
  padding: 16px 40px;
  font-size: 15px;
}

/* ========================================
   Footer
   ======================================== */

.footer {
  padding: 48px 32px;
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.footer-wordmark {
  height: 18px;
  margin: 0 auto 16px;
}

.footer p {
  font-size: 12px;
  color: var(--color-text-muted);
}

.footer a {
  color: var(--color-text-tertiary);
  transition: color 0.2s ease;
}

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

/* ========================================
   Vertical page: feature list
   ======================================== */

.feature-list {
  display: flex;
  flex-direction: column;
  gap: 48px;
  margin-top: 48px;
}

.feature-item {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 24px;
  align-items: start;
}

.feature-item-number {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-amber);
  padding-top: 2px;
}

.feature-item h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.feature-item p {
  font-size: 15px;
  line-height: 1.65;
}

/* ========================================
   Insights placeholder
   ======================================== */

.insights-placeholder {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 32px;
}

.insights-placeholder h2 {
  font-size: 24px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 12px;
}

.insights-placeholder p {
  color: var(--color-text-tertiary);
  font-size: 15px;
}

/* ========================================
   Shared advantages (used on PE + HF pages)
   ======================================== */

.advantages-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-top: 48px;
}

/* ========================================
   Who runs this
   ======================================== */

.founder-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

.founder-block .credential-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.founder-block .credential-list li {
  font-size: 14px;
  color: var(--color-text-secondary);
  padding-left: 16px;
  position: relative;
}

.founder-block .credential-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-amber);
}

/* ========================================
   Responsive
   ======================================== */

@media (max-width: 768px) {
  .nav {
    padding: 0 24px;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(26, 29, 33, 0.97);
    backdrop-filter: blur(20px);
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--color-border);
  }

  .nav-links.open {
    display: flex;
  }

  .nav-toggle {
    display: block;
  }

  .container {
    padding: 0 24px;
  }

  section {
    padding: 64px 0;
  }

  .hero {
    padding: 88px 24px 56px;
    min-height: auto;
  }

  .highlight-section {
    padding: 80px 24px;
  }

  .cta-section {
    padding: 80px 24px;
  }

  .grid-2,
  .grid-3,
  .grid-4,
  .contrast-block,
  .founder-block,
  .advantages-grid {
    grid-template-columns: 1fr;
  }

  .feature-item {
    grid-template-columns: 32px 1fr;
    gap: 16px;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 28px;
  }

  .section-title {
    font-size: 22px;
  }
}