/* =========================================================================
   Bellows — bellowslab.com
   Design tokens, base, components, sections, responsive.
   ========================================================================= */

:root {
  /* Color — named after the bellows/forge metaphor */
  --color-charcoal: #121110;
  --color-charcoal-raised: #1A1918;
  --color-coal: #2A1A15;
  --color-iron: #3A3F44;
  --color-brass: #B08A4A;
  --color-brass-dim: rgba(176, 138, 74, 0.4);
  --color-amber: #F2A03D;
  --color-ember: #C6451F;
  --color-paper: #F5F1EA;
  --color-paper-dim: rgba(245, 241, 234, 0.6);

  /* Gradients */
  --gradient-ember: linear-gradient(135deg, #F2A03D, #C6451F 50%, #2A1A15);
  --gradient-heat:  linear-gradient(90deg,  #F2A03D, #C6451F);

  /* Typography */
  --font-display: "Playfair Display", Georgia, serif;
  --font-body:    "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono:    "JetBrains Mono", ui-monospace, monospace;

  /* Motion */
  --ease-exhale:   cubic-bezier(0.16, 1, 0.3, 1);
  --ease-compress: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-glide:    cubic-bezier(0.4, 0, 0.2, 1);
}

/* =========================================================================
   Base
   ========================================================================= */

*,
*::before,
*::after { box-sizing: border-box; margin: 0; padding: 0; }

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

body {
  font-family: var(--font-body);
  background: var(--color-charcoal);
  color: var(--color-paper);
  line-height: 1.7;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }
input, textarea { font-family: inherit; }

.mono {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.dim { opacity: 0.45; }
.sep { opacity: 0.3; }

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 32px;
}

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

.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 24px 0;
  transition: background 0.3s;
}
.nav.is-scrolled {
  background: rgba(18, 17, 16, 0.9);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}
.nav-inner {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.nav-logo { display: flex; align-items: center; gap: 12px; }
.nav-logo-mark {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 24px;
  background: var(--gradient-heat);
  -webkit-background-clip: text;
          background-clip: text;
  -webkit-text-fill-color: transparent;
}
.nav-logo-text {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 18px;
  letter-spacing: -0.02em;
}
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-paper-dim);
  transition: color 0.2s;
}
.nav-link:hover { color: var(--color-paper); }
.nav-link--cta {
  padding: 8px 24px;
  border: 1px solid var(--color-iron);
  border-radius: 100px;
  transition: border-color 0.3s;
}
.nav-link--cta:hover { border-color: var(--color-brass); }

/* =========================================================================
   Section shell
   ========================================================================= */

.section { padding: 160px 0; }

.section-label {
  font-family: var(--font-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-brass);
  margin-bottom: 48px;
  display: flex;
  gap: 16px;
}
.section-label .mono { font-size: 12px; opacity: 0.5; }

.section-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(42px, 6vw, 72px);
  line-height: 1.05;
  letter-spacing: -0.02em;
  margin-bottom: 32px;
}
.section-subtitle {
  font-size: 18px;
  line-height: 1.7;
  color: var(--color-paper-dim);
  max-width: 640px;
  margin-bottom: 64px;
}

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

.section--hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 160px 0 120px;
  overflow: hidden;
  position: relative;
}
.hero-bg-glow {
  position: absolute;
  top: -20%; right: -10%;
  width: 80vw; height: 80vw;
  background: radial-gradient(ellipse,
    rgba(198, 69, 31, 0.06),
    rgba(242, 160, 61, 0.03) 30%,
    transparent 70%);
  pointer-events: none;
}
.hero-container { position: relative; z-index: 1; }
.hero-eyebrow {
  color: var(--color-brass);
  margin-bottom: 40px;
  font-size: 12px;
  letter-spacing: 0.12em;
}
.hero-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(52px, 8.5vw, 120px);
  line-height: 0.95;
  letter-spacing: -0.03em;
  margin-bottom: 48px;
}
.hero-title-line { display: block; }
.ember-word {
  background: var(--gradient-heat);
  -webkit-background-clip: text;
          background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-body {
  max-width: 560px;
  margin-left: auto;
  padding-left: 32px;
}
.hero-definition {
  max-width: 560px;
  margin: 32px 0 32px auto;
  padding: 16px 0 16px 32px;
  border-left: 1px solid var(--color-brass);
  color: var(--color-paper-dim);
}
.hero-definition-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 6px;
  flex-wrap: wrap;
}
.hero-definition-word {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 600;
  font-size: 22px;
  color: var(--color-paper);
  letter-spacing: 0.01em;
}
.hero-definition-meta {
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  opacity: 0.55;
}
.hero-definition-body {
  font-size: 15px;
  line-height: 1.6;
  margin: 0;
}
@media (max-width: 640px) {
  .hero-definition { margin-left: 0; padding-left: 20px; }
}
.hero-text {
  font-size: 18px;
  line-height: 1.7;
  color: var(--color-paper-dim);
  margin-bottom: 40px;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-meta {
  margin-top: 96px;
  display: flex;
  gap: 12px;
  color: var(--color-paper-dim);
  font-size: 11px;
  opacity: 0.4;
}
.hero-scroll-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(to bottom, var(--color-brass), transparent);
  position: absolute;
  bottom: 40px;
  left: 50%;
  animation: scroll-pulse 2s var(--ease-exhale) infinite;
}
@keyframes scroll-pulse {
  0%, 100% { opacity: 0.2; transform: scaleY(0.6); }
  50%      { opacity: 0.6; transform: scaleY(1); }
}

/* =========================================================================
   Value section
   ========================================================================= */

.value-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  margin-top: 48px;
}
.value-card {
  padding: 40px 32px;
  border: 1px solid rgba(245, 241, 234, 0.06);
  border-radius: 12px;
  background: var(--color-charcoal-raised);
  transition: border-color 0.3s, box-shadow 0.6s;
}
.value-card:hover {
  border-color: rgba(176, 138, 74, 0.2);
  box-shadow: 0 0 40px rgba(242, 160, 61, 0.06);
}
.value-card-number { color: var(--color-brass); font-size: 12px; margin-bottom: 24px; }
.value-card-rule {
  width: 40px; height: 2px;
  background: var(--gradient-heat);
  margin-bottom: 24px;
}
.value-card-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(28px, 3vw, 36px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}
.value-card-body {
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-paper-dim);
  margin-bottom: 32px;
}
.value-card-proof {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-top: 24px;
  border-top: 1px solid rgba(245, 241, 234, 0.06);
  color: var(--color-brass-dim);
  font-size: 11px;
}

/* =========================================================================
   Use Cases
   ========================================================================= */

.section--use-cases { background: var(--color-charcoal-raised); }

.usecase-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 64px;
}
.usecase-card {
  padding: 40px;
  border: 1px solid rgba(245, 241, 234, 0.06);
  border-radius: 12px;
  background: var(--color-charcoal);
  transition: border-color 0.3s;
  display: flex;
  flex-direction: column;
}
.usecase-card:hover { border-color: rgba(176, 138, 74, 0.2); }
.usecase-eyebrow {
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-brass);
  margin-bottom: 20px;
  line-height: 1.5;
}
.usecase-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(22px, 2.4vw, 28px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  margin-bottom: 20px;
  color: var(--color-paper);
}
.usecase-body {
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-paper-dim);
  margin-bottom: 24px;
}
.usecase-outcome {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 400;
  font-size: 17px;
  line-height: 1.5;
  color: var(--color-paper);
  padding-left: 20px;
  border-left: 1px solid var(--color-brass);
  margin-bottom: 24px;
}
.usecase-link {
  margin-top: auto;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-brass);
  text-decoration: none;
  transition: color 0.2s, letter-spacing 0.2s;
  align-self: flex-start;
}
.usecase-link:hover {
  color: var(--color-paper);
  letter-spacing: 0.12em;
}

/* =========================================================================
   Difference
   ========================================================================= */

.diff-statements { margin: 64px 0; }
.diff-statement {
  padding: 48px 0;
  border-bottom: 1px solid rgba(245, 241, 234, 0.06);
}
.diff-statement:first-child { border-top: 1px solid rgba(245, 241, 234, 0.06); }
.diff-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(32px, 5vw, 64px);
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.diff-title em {
  font-style: normal;
  background: var(--gradient-heat);
  -webkit-background-clip: text;
          background-clip: text;
  -webkit-text-fill-color: transparent;
}
.diff-body {
  max-width: 640px;
  margin-left: auto;
  margin-top: 64px;
}
.diff-body p {
  font-size: 17px;
  line-height: 1.8;
  color: var(--color-paper-dim);
}

/* =========================================================================
   Why Now
   ========================================================================= */

.stat-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 48px;
}
.stat-card {
  padding: 40px 32px;
  border: 1px solid rgba(245, 241, 234, 0.06);
  border-radius: 12px;
  background: var(--color-charcoal-raised);
  transition: border-color 0.3s;
}
.stat-card:hover { border-color: rgba(176, 138, 74, 0.2); }
.stat-value {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(40px, 5vw, 64px);
  line-height: 1;
  letter-spacing: -0.03em;
  background: var(--gradient-heat);
  -webkit-background-clip: text;
          background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 24px;
}
.stat-description {
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-paper-dim);
  margin-bottom: 24px;
}
.stat-source {
  display: inline-block;
  color: var(--color-brass);
  font-size: 11px;
  border-bottom: 1px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}
.stat-source:hover {
  color: var(--color-amber);
  border-bottom-color: currentColor;
}
.why-body {
  max-width: 640px;
  margin-left: auto;
  margin-top: 64px;
}
.why-body p {
  font-size: 17px;
  line-height: 1.8;
  color: var(--color-paper-dim);
}
.why-body .why-callout {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(28px, 3.2vw, 40px);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--color-paper);
  margin-bottom: 24px;
}
.why-body .why-callout + p { padding-top: 4px; }

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 16px 32px;
  font-size: 15px;
  font-weight: 500;
  border-radius: 100px;
  transition: all 0.3s;
  white-space: nowrap;
}
.btn--full { width: 100%; }
.btn--primary { background: var(--color-paper); color: var(--color-charcoal); }
.btn--primary:hover { background: #fff; transform: translateY(-1px); }
.btn--primary:disabled { opacity: 0.3; cursor: not-allowed; transform: none; }
.btn--ghost { color: var(--color-paper); border: 1px solid var(--color-iron); }
.btn--ghost:hover { border-color: var(--color-brass); }
.btn--ember { background: var(--gradient-heat); color: var(--color-paper); }
.btn--ember:hover { transform: translateY(-1px); }

/* =========================================================================
   Forms
   ========================================================================= */

.form-field { display: flex; flex-direction: column; gap: 8px; }
.form-field--full { grid-column: 1 / -1; }
.form-label { font-size: 13px; font-weight: 500; color: var(--color-paper-dim); }
.form-input,
.form-textarea {
  padding: 16px;
  background: var(--color-charcoal-raised);
  border: 1px solid rgba(245, 241, 234, 0.08);
  border-radius: 8px;
  color: var(--color-paper);
  font-size: 15px;
  outline: none;
  transition: border-color 0.2s;
}
.form-input:focus,
.form-textarea:focus { border-color: var(--color-brass); }
.form-input::placeholder,
.form-textarea::placeholder { color: rgba(245, 241, 234, 0.2); }
.form-textarea { resize: vertical; min-height: 80px; }

/* =========================================================================
   Contact
   ========================================================================= */

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
}
.contact-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(36px, 5vw, 56px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 32px;
}
.contact-body {
  font-size: 17px;
  line-height: 1.7;
  color: var(--color-paper-dim);
  margin-bottom: 40px;
}
.contact-details {
  display: flex;
  flex-direction: column;
  gap: 8px;
  color: var(--color-brass);
  font-size: 13px;
}
.contact-details a { transition: color 0.2s; }
.contact-details a:hover { color: var(--color-amber); }
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

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

.footer {
  padding: 64px 0 40px;
  border-top: 1px solid rgba(245, 241, 234, 0.06);
}
.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-logo-mark { font-size: 24px; }
.footer-logo-text { font-size: 20px; }
.footer-tagline {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 16px;
  color: var(--color-brass-dim);
}
.footer-divider {
  height: 1px;
  background: rgba(245, 241, 234, 0.06);
  margin: 32px 0;
}
.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-links { display: flex; gap: 32px; }
.footer-links a {
  font-size: 14px;
  color: var(--color-paper-dim);
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--color-paper); }
.footer-meta {
  display: flex;
  gap: 12px;
  color: var(--color-paper-dim);
  font-size: 11px;
  opacity: 0.5;
}

/* =========================================================================
   Reveal-on-scroll
   ========================================================================= */

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.9s var(--ease-exhale),
              transform 0.9s var(--ease-compress);
}
.reveal.is-visible { opacity: 1; transform: translateY(0); }

.reveal-card {
  opacity: 0;
  transform: translateY(40px) scale(0.97);
  transition: opacity 0.9s var(--ease-exhale),
              transform 0.9s var(--ease-compress);
}
.reveal-card.is-visible { opacity: 1; transform: translateY(0) scale(1); }
.reveal-card:nth-child(2) { transition-delay: 120ms; }
.reveal-card:nth-child(3) { transition-delay: 240ms; }
.reveal-card:nth-child(4) { transition-delay: 360ms; }

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

@media (max-width: 960px) {
  .section { padding: 120px 0; }
  .value-grid,
  .stat-grid { grid-template-columns: 1fr; }
  .usecase-grid,
  .contact-grid { grid-template-columns: 1fr; }
  .contact-grid { gap: 48px; }
  .hero-body { margin-left: 0; padding-left: 0; }
  .nav-links .nav-link:not(.nav-link--cta) { display: none; }
  .footer-top,
  .footer-bottom { flex-direction: column; gap: 24px; align-items: flex-start; }
}

@media (max-width: 640px) {
  .container,
  .nav-inner { padding: 0 20px; }
  .section { padding: 96px 0; }
  .section--hero { padding: 140px 0 80px; }
  .section-label { margin-bottom: 32px; }
  .value-card,
  .usecase-card,
  .stat-card { padding: 32px 24px; }
  .hero-meta { margin-top: 64px; flex-wrap: wrap; }
  .hero-actions .btn { flex: 1 1 auto; }
  .footer { padding: 48px 0 32px; }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .reveal,
  .reveal-card { opacity: 1; transform: none; }
}