/* ---------- Design tokens (grayscale, matches the Kinesim app) ---------- */

:root {
  --k-bg: #0a0a0b;
  --k-bg-elevated: #111113;
  --k-surface: #17171a;
  --k-surface-2: #1e1e22;
  --k-border: #2a2a2e;
  --k-border-strong: #3a3a40;
  --k-text: #f5f5f6;
  --k-text-secondary: #a3a3a8;
  --k-text-muted: #6b6b70;
  --k-accent: #ffffff;
  --k-accent-contrast: #0a0a0b;

  --k-font-sans: 'Poppins', -apple-system, BlinkMacSystemFont, sans-serif;
  --k-font-heading: 'Bricolage Grotesque', 'Poppins', sans-serif;

  --k-radius-sm: 6px;
  --k-radius: 10px;
  --k-radius-lg: 20px;

  --k-container: 1120px;

  --k-shadow: 0 1px 0 rgba(255, 255, 255, 0.04) inset, 0 20px 40px -24px rgba(0, 0, 0, 0.6);
}

:root[data-theme='light'] {
  --k-bg: #ffffff;
  --k-bg-elevated: #fbfbfc;
  --k-surface: #f5f5f6;
  --k-surface-2: #eeeeef;
  --k-border: #dadadf;
  --k-border-strong: #c3c3c8;
  --k-text: #121214;
  --k-text-secondary: #5c5c62;
  --k-text-muted: #9a9aa0;
  --k-accent: #121214;
  --k-accent-contrast: #ffffff;

  --k-shadow: 0 1px 0 rgba(255, 255, 255, 0.6) inset, 0 20px 40px -24px rgba(18, 18, 20, 0.14);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme='dark']) {
    --k-bg: #ffffff;
    --k-bg-elevated: #fbfbfc;
    --k-surface: #f5f5f6;
    --k-surface-2: #eeeeef;
    --k-border: #dadadf;
    --k-border-strong: #c3c3c8;
    --k-text: #121214;
    --k-text-secondary: #5c5c62;
    --k-text-muted: #9a9aa0;
    --k-accent: #121214;
    --k-accent-contrast: #ffffff;
    --k-shadow: 0 1px 0 rgba(255, 255, 255, 0.6) inset, 0 20px 40px -24px rgba(18, 18, 20, 0.14);
  }
}

/* ---------- Reset ---------- */

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--k-bg);
  color: var(--k-text);
  font-family: var(--k-font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.25s ease, color 0.25s ease;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-family: var(--k-font-heading);
  font-weight: 700;
  line-height: 1.12;
  margin: 0 0 0.5em;
  letter-spacing: -0.01em;
}

p { margin: 0 0 1em; color: var(--k-text-secondary); }

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

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

button { font-family: inherit; }

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

.text-muted { color: var(--k-text-muted); }

/* ---------- Background grid ---------- */

.bg-grid {
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(to right, var(--k-border) 1px, transparent 1px),
    linear-gradient(to bottom, var(--k-border) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: 0.35;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 10%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 10%, transparent 75%);
}

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  backdrop-filter: blur(10px);
  background: color-mix(in srgb, var(--k-bg) 78%, transparent);
  border-bottom: 1px solid var(--k-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  height: 72px;
}

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

.brand-mark {
  width: 26px;
  height: 26px;
  object-fit: contain;
}

.brand-name {
  font-family: var(--k-font-heading);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.01em;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
  font-size: 0.92rem;
  color: var(--k-text-secondary);
}

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

.nav-cta {
  padding: 9px 16px;
  border-radius: 999px;
  background: var(--k-accent);
  color: var(--k-accent-contrast) !important;
  font-weight: 600;
}

.nav-cta:hover { opacity: 0.88; }

.theme-toggle {
  width: 38px;
  height: 38px;
  border-radius: 999px;
  border: 1px solid var(--k-border);
  background: var(--k-surface);
  color: var(--k-text);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  flex-shrink: 0;
}

.theme-toggle:hover { border-color: var(--k-border-strong); }

.icon { width: 18px; height: 18px; }
.icon-sun { display: none; }
.icon-moon { display: block; }
:root[data-theme='light'] .icon-sun { display: block; }
:root[data-theme='light'] .icon-moon { display: none; }

/* ---------- Hero ---------- */

.hero {
  position: relative;
  padding: 108px 0 96px;
  overflow: hidden;
}

.hero-inner {
  max-width: 760px;
}

.eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--k-text-muted);
  padding: 6px 12px;
  border: 1px solid var(--k-border);
  border-radius: 999px;
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  color: var(--k-text);
}

.hero-sub {
  font-size: 1.1rem;
  max-width: 600px;
  margin-top: 20px;
  margin-bottom: 36px;
}

.hero-visual {
  position: absolute;
  top: -120px;
  right: -180px;
  width: 640px;
  height: 640px;
  pointer-events: none;
  opacity: 0.5;
}

.pinwheel-ring {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  border: 1px dashed var(--k-border-strong);
  animation: spin 90s linear infinite;
}

.pinwheel-ring::before,
.pinwheel-ring::after {
  content: '';
  position: absolute;
  inset: 70px;
  border-radius: 50%;
  border: 1px dashed var(--k-border);
}

.pinwheel-ring::after {
  inset: 150px;
  animation: spin 60s linear infinite reverse;
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@media (prefers-reduced-motion: reduce) {
  .pinwheel-ring, .pinwheel-ring::after { animation: none; }
  html { scroll-behavior: auto; }
}

/* ---------- Waitlist form ---------- */

.waitlist-form { max-width: 480px; }

.field-row {
  display: flex;
  gap: 10px;
}

.honeypot {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.email-input {
  flex: 1;
  min-width: 0;
  padding: 13px 16px;
  border-radius: var(--k-radius);
  border: 1px solid var(--k-border-strong);
  background: var(--k-surface);
  color: var(--k-text);
  font-family: var(--k-font-sans);
  font-size: 0.96rem;
}

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

.email-input:focus {
  outline: none;
  border-color: var(--k-text-secondary);
}

.btn {
  padding: 13px 22px;
  border-radius: var(--k-radius);
  border: none;
  font-weight: 600;
  font-size: 0.96rem;
  cursor: pointer;
  white-space: nowrap;
  transition: opacity 0.15s ease, transform 0.1s ease;
}

.btn:active { transform: scale(0.98); }

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

.btn-primary:hover { opacity: 0.88; }
.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; }

.form-note {
  margin: 12px 2px 0;
  font-size: 0.82rem;
  color: var(--k-text-muted);
}

.form-note[data-state='success'] { color: var(--k-text); font-weight: 500; }
.form-note[data-state='error'] { color: #e0575a; }

@media (max-width: 520px) {
  .field-row { flex-direction: column; }
  .btn { width: 100%; }
}

/* ---------- Sections ---------- */

.section { padding: 88px 0; }
.section-alt { background: var(--k-bg-elevated); border-top: 1px solid var(--k-border); border-bottom: 1px solid var(--k-border); }

.section-title {
  font-size: clamp(1.8rem, 3vw, 2.3rem);
  max-width: 640px;
}

/* About */

.about-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 64px;
  align-items: center;
}

.about-copy h2 { font-size: clamp(1.8rem, 3vw, 2.3rem); max-width: 480px; }
.about-copy p { max-width: 480px; }

.about-visual {
  display: flex;
  justify-content: center;
  color: var(--k-text-muted);
}

.circuit-art {
  width: 100%;
  max-width: 400px;
  height: auto;
}

@media (max-width: 860px) {
  .about-grid { grid-template-columns: 1fr; gap: 40px; }
  .about-visual { order: -1; }
}

/* Features */

.feature-grid {
  margin-top: 44px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.feature-card {
  padding: 28px 24px;
  border-radius: var(--k-radius-lg);
  background: var(--k-surface);
  border: 1px solid var(--k-border);
}

.feature-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--k-radius-sm);
  background: var(--k-surface-2);
  border: 1px solid var(--k-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--k-text);
  margin-bottom: 18px;
}

.feature-icon svg { width: 20px; height: 20px; }

.feature-card h3 {
  font-size: 1.05rem;
  margin-bottom: 8px;
}

.feature-card p { font-size: 0.92rem; margin-bottom: 0; }

@media (max-width: 980px) {
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 560px) {
  .feature-grid { grid-template-columns: 1fr; }
}

/* How it works */

.how-grid { max-width: 760px; }

.how-list {
  margin-top: 36px;
  display: grid;
  gap: 28px;
}

.how-item {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 20px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--k-border);
}

.how-item:last-child { border-bottom: none; padding-bottom: 0; }

.how-index {
  font-family: var(--k-font-heading);
  font-weight: 700;
  font-size: 1rem;
  color: var(--k-text-muted);
}

.how-item h3 { font-size: 1.02rem; margin-bottom: 6px; }
.how-item p { margin-bottom: 0; font-size: 0.95rem; }

/* CTA / waitlist section */

.section-cta {
  text-align: center;
  background: var(--k-bg-elevated);
  border-top: 1px solid var(--k-border);
}

.cta-inner {
  max-width: 560px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.cta-mark {
  width: 44px;
  height: 44px;
  object-fit: contain;
  margin-bottom: 24px;
  opacity: 0.9;
}

.section-cta h2 { font-size: clamp(1.8rem, 3vw, 2.2rem); }
.section-cta p { margin-bottom: 32px; }
.section-cta .waitlist-form { width: 100%; }
.section-cta .form-note { text-align: left; }

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--k-border);
  padding: 32px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-copy {
  margin: 0;
  font-size: 0.85rem;
  color: var(--k-text-muted);
}

/* ---------- Responsive header ---------- */

@media (max-width: 680px) {
  .header-inner { height: 64px; }
  .brand-name { font-size: 1rem; }
  .site-nav { gap: 10px; }
  .site-nav a:not(.nav-cta) { display: none; }
  .nav-cta { padding: 8px 14px; font-size: 0.86rem; }
}