/* ========================================
   OFA — Order Flow Transformer
   Transparent Aero / Glassmorphism Theme
   ======================================== */

:root {
  /* Type Scale */
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);
  --text-3xl:  clamp(2.5rem,   1rem    + 4vw,    5rem);
  --text-hero: clamp(3rem,     0.5rem  + 7vw,    8rem);

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Fonts */
  --font-body: 'Satoshi', 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', 'Consolas', monospace;
  --font-display: 'Satoshi', 'Inter', sans-serif;

  /* Easing */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in:  cubic-bezier(0.4, 0, 1, 1);
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;
}

/* ============ Dark Theme (default) ============ */
[data-theme="dark"] {
  --color-bg:           #09090b;
  --color-surface:      #111113;
  --color-surface-2:    #18181b;
  --color-border:       rgba(255, 255, 255, 0.06);
  --color-border-hover: rgba(255, 255, 255, 0.12);
  --color-text:         #e4e4e7;
  --color-text-muted:   #71717a;
  --color-text-faint:   #3f3f46;

  --color-accent:       #C9A84C;
  --color-accent-light: #E8D48B;
  --color-accent-dim:   rgba(201, 168, 76, 0.15);
  --color-accent-glow:  rgba(201, 168, 76, 0.08);

  --glass-bg:          rgba(255, 255, 255, 0.03);
  --glass-bg-hover:    rgba(255, 255, 255, 0.05);
  --glass-border:      rgba(255, 255, 255, 0.06);
  --glass-blur:        16px;

  --nav-bg:            rgba(9, 9, 11, 0.7);
  --section-alt-bg:    rgba(255, 255, 255, 0.01);
  --btn-primary-text:  #09090b;
  --accent-border:     rgba(201, 168, 76, 0.3);
  --accent-border-hover: rgba(201, 168, 76, 0.5);
  --accent-bg-subtle:  rgba(201, 168, 76, 0.05);
  --accent-bg-hover:   rgba(201, 168, 76, 0.1);
  --accent-glow-shadow: rgba(201, 168, 76, 0.2);
  --grid-line-color:   rgba(201, 168, 76, 0.03);
  --scrollbar-thumb:   rgba(201, 168, 76, 0.35);
  --scrollbar-hover:   rgba(201, 168, 76, 0.5);
}

/* ============ Light Theme ============ */
[data-theme="light"] {
  --color-bg:           #f5f3ef;
  --color-surface:      #edeae4;
  --color-surface-2:    #e5e2db;
  --color-border:       rgba(0, 0, 0, 0.08);
  --color-border-hover: rgba(0, 0, 0, 0.15);
  --color-text:         #1a1815;
  --color-text-muted:   #6b6560;
  --color-text-faint:   #a8a29e;

  --color-accent:       #9A7B2E;
  --color-accent-light: #C9A84C;
  --color-accent-dim:   rgba(154, 123, 46, 0.12);
  --color-accent-glow:  rgba(154, 123, 46, 0.06);

  --glass-bg:          rgba(0, 0, 0, 0.025);
  --glass-bg-hover:    rgba(0, 0, 0, 0.045);
  --glass-border:      rgba(0, 0, 0, 0.07);
  --glass-blur:        20px;

  --nav-bg:            rgba(245, 243, 239, 0.75);
  --section-alt-bg:    rgba(0, 0, 0, 0.015);
  --btn-primary-text:  #f5f3ef;
  --accent-border:     rgba(154, 123, 46, 0.3);
  --accent-border-hover: rgba(154, 123, 46, 0.5);
  --accent-bg-subtle:  rgba(154, 123, 46, 0.06);
  --accent-bg-hover:   rgba(154, 123, 46, 0.12);
  --accent-glow-shadow: rgba(154, 123, 46, 0.15);
  --grid-line-color:   rgba(154, 123, 46, 0.05);
  --scrollbar-thumb:   rgba(154, 123, 46, 0.3);
  --scrollbar-hover:   rgba(154, 123, 46, 0.45);
}

/* ============ Theme Transition ============ */
.nav,
.glass-card,
.stat,
.metric-card,
.signal-card,
.cta-form__input,
.signal-card__tag,
.glass-card__icon,
.nav__cta,
.btn--ghost,
.section--alt,
.footer {
  transition: background-color 0.6s ease,
              border-color 0.6s ease,
              color 0.6s ease,
              box-shadow 0.6s ease;
}

/* ============ Particle Canvas ============ */
#particles {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

/* ============ Navigation ============ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--nav-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--glass-border);
}

.nav__inner {
  max-width: var(--content-wide);
  margin: 0 auto;
  padding: var(--space-4) var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-8);
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}

.nav__wordmark {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.2em;
  color: var(--color-accent);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-8);
}

.nav__links a {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  text-decoration: none;
}

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

.nav__cta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
  padding: var(--space-2) var(--space-5);
  border: 1px solid var(--accent-border);
  border-radius: var(--radius-sm);
  color: var(--color-accent);
  background: var(--accent-bg-subtle);
}

.nav__cta:hover {
  background: var(--accent-bg-hover);
  border-color: var(--accent-border-hover);
}

/* ============ Hero ============ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: calc(var(--space-32) + var(--space-8)) var(--space-6) var(--space-16);
  overflow: hidden;
  z-index: 1;
}

.hero__grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid-line-color) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line-color) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 20%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 20%, transparent 70%);
}

.hero__content {
  max-width: var(--content-wide);
  margin: 0 auto;
  width: 100%;
  position: relative;
  z-index: 2;
}

.hero__tag {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-6);
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out) 0.2s forwards;
}

.hero__title {
  font-family: var(--font-display);
  font-size: var(--text-hero);
  font-weight: 700;
  line-height: 0.95;
  letter-spacing: -0.03em;
  color: var(--color-text);
  margin-bottom: var(--space-8);
}

.hero__title-line {
  display: block;
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out) 0.4s forwards;
}

.hero__title-accent {
  background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-light) 50%, var(--color-accent) 100%);
  background-size: 200% 100%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: fadeUp 0.8s var(--ease-out) 0.5s forwards, shimmer 6s ease-in-out infinite 1.5s;
}

@keyframes shimmer {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.hero__sub {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 600px;
  line-height: 1.6;
  margin-bottom: var(--space-10);
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out) 0.6s forwards;
}

.hero__actions {
  display: flex;
  gap: var(--space-4);
  margin-bottom: var(--space-16);
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out) 0.7s forwards;
}

.hero__stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-1);
  max-width: 720px;
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out) 0.9s forwards;
}

.stat {
  padding: var(--space-5) var(--space-6);
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
}

.stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-accent);
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}

.stat__label {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  letter-spacing: 0.03em;
  margin-top: var(--space-1);
}

.hero__visual {
  position: absolute;
  top: 50%;
  right: 0;
  transform: translateY(-50%);
  width: 45%;
  height: 60%;
  opacity: 0.25;
  z-index: 1;
}

#flow-viz {
  width: 100%;
  height: 100%;
}

/* ============ Buttons ============ */
.btn {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.05em;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-sm);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  transition: all var(--transition-interactive);
}

.btn--primary {
  background: linear-gradient(135deg, var(--color-accent), #B8943F);
  color: var(--btn-primary-text);
  font-weight: 600;
}

.btn--primary:hover {
  box-shadow: 0 0 30px var(--accent-glow-shadow);
  transform: translateY(-1px);
}

.btn--primary:active {
  transform: translateY(0);
}

.btn--ghost {
  border: 1px solid var(--color-border-hover);
  color: var(--color-text-muted);
  background: transparent;
}

.btn--ghost:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: var(--color-accent-dim);
}

/* ============ Sections ============ */
.section {
  position: relative;
  z-index: 1;
  padding: clamp(var(--space-16), 8vw, var(--space-32)) var(--space-6);
}

.section--alt {
  background: var(--section-alt-bg);
}

.section__inner {
  max-width: var(--content-wide);
  margin: 0 auto;
}

.section__tag {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-4);
}

.section__title {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

.section__desc {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  max-width: 560px;
  line-height: 1.7;
  margin-bottom: var(--space-12);
}

/* ============ Glass Cards ============ */
.glass-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  transition: all 300ms var(--ease-out);
}

.glass-card:hover {
  background: var(--glass-bg-hover);
  border-color: var(--color-border-hover);
  transform: translateY(-2px);
}

.glass-card__icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background: var(--color-accent-dim);
  color: var(--color-accent);
  margin-bottom: var(--space-5);
}

.glass-card__title {
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.glass-card__text {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.65;
}

.glass-card--compact {
  padding: var(--space-6);
}

/* ============ Architecture Grid ============ */
.arch-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
}

/* ============ Data / Timeline ============ */
.data-timeline {
  margin-bottom: var(--space-12);
  overflow-x: auto;
  padding-bottom: var(--space-4);
  scrollbar-color: var(--scrollbar-thumb) transparent;
  scrollbar-width: thin;
}

.timeline {
  position: relative;
  min-width: 800px;
  height: 200px;
  padding-top: var(--space-12);
}

.timeline__line {
  position: absolute;
  top: calc(var(--space-12) + 6px);
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-accent), transparent);
  opacity: 0.4;
}

.timeline__node {
  position: absolute;
  left: var(--pos);
  top: var(--space-12);
  transform: translateX(-50%);
}

.timeline__node::before {
  content: '';
  display: block;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-bg);
  border: 2px solid var(--color-accent);
  margin: 0 auto var(--space-3);
  position: relative;
  z-index: 2;
}

.timeline__year {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 700;
  color: var(--color-accent);
  text-align: center;
  margin-bottom: var(--space-1);
}

.timeline__event {
  display: block;
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-align: center;
  white-space: nowrap;
  line-height: 1.5;
}

.timeline__detail {
  color: var(--color-text-faint);
  font-size: 0.7rem;
}

/* ============ Data Features ============ */
.data-features {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-4);
}

.data-feat__label {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-4);
}

.data-feat__list {
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.data-feat__list li {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  padding-left: var(--space-4);
  position: relative;
}

.data-feat__list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 1px;
  background: var(--color-accent);
  opacity: 0.5;
}

/* ============ Metrics ============ */
.metrics-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
}

.metric-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
}

.metric-card__bar {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--color-accent), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 1.2s var(--ease-out);
}

.metric-card.in-view .metric-card__bar {
  transform: scaleX(var(--pct, 0));
}

.metric-card__value {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
  font-variant-numeric: tabular-nums;
  margin-bottom: var(--space-2);
}

.metric-card__label {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  letter-spacing: 0.02em;
}

/* ============ Signals ============ */
.signals-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
}

.signal-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  transition: all 300ms var(--ease-out);
}

.signal-card:hover {
  background: var(--glass-bg-hover);
  border-color: var(--color-border-hover);
}

.signal-card__header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-3);
}

.signal-card__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  flex-shrink: 0;
}

.signal-card__dot--live {
  background: var(--color-accent);
  box-shadow: 0 0 8px var(--color-accent);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.signal-card__name {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
}

.signal-card__desc {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  line-height: 1.65;
  margin-bottom: var(--space-4);
}

.signal-card__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-sm);
  background: var(--color-accent-dim);
  color: var(--color-accent);
}

/* ============ CTA Section ============ */
.cta-section {
  position: relative;
  z-index: 1;
  padding: var(--space-24) var(--space-6);
  text-align: center;
}

.cta-section__inner {
  max-width: 540px;
  margin: 0 auto;
}

.cta-section__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

.cta-section__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin: 0 auto var(--space-8);
  max-width: 440px;
}

.cta-form {
  display: flex;
  gap: var(--space-2);
  max-width: 440px;
  margin: 0 auto var(--space-4);
}

.cta-form__input {
  flex: 1;
  padding: var(--space-3) var(--space-5);
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text);
  outline: none;
}

.cta-form__input::placeholder {
  color: var(--color-text-faint);
}

.cta-form__input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-dim);
}

.cta-section__note {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  letter-spacing: 0.02em;
}

/* ============ Footer ============ */
.footer {
  position: relative;
  z-index: 1;
  border-top: 1px solid var(--glass-border);
  padding: var(--space-6);
}

.footer__inner {
  max-width: var(--content-wide);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer__left {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.footer__brand {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-accent);
  letter-spacing: 0.15em;
}

.footer__copy {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}

.footer__link {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  text-decoration: none;
}

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

/* ============ Animations ============ */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Scroll reveals */
.fade-in {
  opacity: 1;
}

@supports (animation-timeline: scroll()) {
  .fade-in {
    opacity: 0;
    animation: reveal-fade linear both;
    animation-timeline: view();
    animation-range: entry 0% entry 100%;
  }
}

@keyframes reveal-fade {
  to { opacity: 1; }
}

/* ============ Mobile ============ */
@media (max-width: 768px) {
  .nav__links {
    display: none;
  }

  .hero__stats {
    grid-template-columns: repeat(2, 1fr);
    max-width: 100%;
  }

  .hero__visual {
    display: none;
  }

  .arch-grid,
  .data-features {
    grid-template-columns: 1fr;
  }

  .metrics-grid,
  .signals-grid {
    grid-template-columns: 1fr;
  }

  .hero__actions {
    flex-direction: column;
    align-items: flex-start;
  }

  .cta-form {
    flex-direction: column;
  }

  .footer__inner {
    flex-direction: column;
    gap: var(--space-3);
    text-align: center;
  }

  .footer__left {
    flex-direction: column;
    gap: var(--space-2);
  }
}

@media (max-width: 480px) {
  .hero__stats {
    grid-template-columns: 1fr 1fr;
  }
}