/* =========================================================
   CastSense AI — Design Tokens
   Art direction: dusk-on-the-water. A real coach who's been
   out there with you — not a SaaS dashboard. Deep tide-teal
   and low-tide slate, warm at dawn/dusk (amber), earned amber
   accent used sparingly for CTAs and the one proof moment.
   ========================================================= */
:root {
  /* ---- Color: Light (default) ---- */
  --color-bg: oklch(97% 0.008 200);
  --color-surface: oklch(99% 0.004 200);
  --color-surface-alt: oklch(94.5% 0.014 200);
  --color-border: oklch(80% 0.02 200 / 0.5);
  --color-border-strong: oklch(70% 0.03 200 / 0.6);

  --color-text: oklch(22% 0.02 220);
  --color-text-muted: oklch(42% 0.02 215);
  --color-text-faint: oklch(62% 0.015 210);

  --color-primary: oklch(35% 0.08 205);      /* deep tide teal */
  --color-primary-hover: oklch(27% 0.075 205);
  --color-on-primary: oklch(98% 0.01 200);
  --color-cta-bg: oklch(35% 0.08 205);
  --color-on-cta: oklch(98% 0.01 200);

  --color-accent: oklch(68% 0.15 55);        /* dusk amber */
  --color-accent-hover: oklch(60% 0.16 50);
  --color-on-accent: oklch(18% 0.02 50);

  --color-success: oklch(50% 0.11 145);
  --color-warning: oklch(55% 0.14 55);

  --shadow-color: 205 30% 20%;
  --shadow-sm: 0 1px 2px hsl(var(--shadow-color) / 0.08);
  --shadow-md: 0 4px 16px hsl(var(--shadow-color) / 0.10), 0 1px 3px hsl(var(--shadow-color) / 0.08);
  --shadow-lg: 0 16px 40px hsl(var(--shadow-color) / 0.14), 0 4px 10px hsl(var(--shadow-color) / 0.08);

  /* ---- Type scale (fluid) ---- */
  --text-xs: clamp(0.75rem, 0.72rem + 0.1vw, 0.8125rem);
  --text-sm: clamp(0.875rem, 0.85rem + 0.1vw, 0.9375rem);
  --text-base: clamp(1rem, 0.97rem + 0.15vw, 1.0625rem);
  --text-md: clamp(1.125rem, 1.08rem + 0.25vw, 1.25rem);
  --text-lg: clamp(1.375rem, 1.28rem + 0.5vw, 1.625rem);
  --text-xl: clamp(1.75rem, 1.55rem + 1vw, 2.25rem);
  --text-2xl: clamp(2.25rem, 1.9rem + 1.8vw, 3.25rem);
  --text-hero: clamp(2.25rem, 1.7rem + 2.4vw, 3.375rem);

  /* ---- Spacing (4px base) ---- */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4rem;
  --space-9: 6rem;
  --space-10: 8rem;

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

  /* ---- Fonts ---- */
  --font-display: "Fraunces", "Georgia", serif;
  --font-body: "General Sans", "Inter", -apple-system, sans-serif;

  --ease-standard: cubic-bezier(0.22, 1, 0.36, 1);
}

[data-theme="dark"] {
  --color-bg: oklch(18% 0.018 220);
  --color-surface: oklch(22% 0.02 218);
  --color-surface-alt: oklch(26% 0.022 216);
  --color-border: oklch(38% 0.02 210 / 0.6);
  --color-border-strong: oklch(48% 0.03 208 / 0.7);

  --color-text: oklch(93% 0.01 200);
  --color-text-muted: oklch(74% 0.015 200);
  --color-text-faint: oklch(54% 0.015 200);

  --color-primary: oklch(70% 0.09 195);
  --color-primary-hover: oklch(78% 0.09 192);
  --color-on-primary: oklch(14% 0.02 210);
  --color-cta-bg: oklch(30% 0.05 205);
  --color-on-cta: oklch(95% 0.01 200);

  --color-accent: oklch(74% 0.15 58);
  --color-accent-hover: oklch(80% 0.15 60);
  --color-on-accent: oklch(16% 0.02 50);

  --shadow-color: 210 40% 4%;
}

/* =========================================================
   Base page
   ========================================================= */
body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.6;
  transition: background-color 0.3s var(--ease-standard), color 0.3s var(--ease-standard);
}

.container {
  width: 100%;
  max-width: 1160px;
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 4vw, 2.5rem);
}

.container--narrow {
  max-width: 760px;
}

section {
  position: relative;
}

/* =========================================================
   Header
   ========================================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in oklch, var(--color-bg) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: var(--space-3);
  gap: var(--space-4);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-md);
  letter-spacing: -0.01em;
  text-decoration: none;
  color: var(--color-text);
}

.logo svg { width: 30px; height: 30px; flex-shrink: 0; }

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0.55rem 1.1rem;
  border-radius: var(--radius-md);
  background: var(--color-primary);
  color: var(--color-on-primary);
  font-weight: 600;
  font-size: var(--text-sm);
  text-decoration: none;
  border: none;
  transition: background-color 0.2s var(--ease-standard), transform 0.2s var(--ease-standard);
  min-height: 44px;
}

.header-cta:hover { background: var(--color-primary-hover); transform: translateY(-1px); }

/* =========================================================
   Hero
   ========================================================= */
.hero {
  padding-block: clamp(3.5rem, 8vw, 6.5rem) clamp(3rem, 7vw, 5.5rem);
  overflow: hidden;
}

.hero__grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(2rem, 5vw, 4rem);
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-5);
}

.eyebrow::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent);
  flex-shrink: 0;
}

.hero h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-hero);
  line-height: 1.05;
  letter-spacing: -0.015em;
  color: var(--color-text);
  max-width: 22ch;
}

.hero h1 em {
  font-style: normal;
  color: var(--color-primary);
}

.hero__sub {
  margin-top: var(--space-5);
  font-size: var(--text-md);
  line-height: 1.55;
  color: var(--color-text-muted);
  max-width: 42ch;
}

.hero__actions {
  margin-top: var(--space-7);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  align-items: center;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.9rem 1.6rem;
  border-radius: var(--radius-md);
  background: var(--color-accent);
  color: var(--color-on-accent);
  font-weight: 700;
  font-size: var(--text-base);
  text-decoration: none;
  border: none;
  min-height: 48px;
  transition: background-color 0.2s var(--ease-standard), transform 0.2s var(--ease-standard), box-shadow 0.2s var(--ease-standard);
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.hero__microcopy {
  font-size: var(--text-sm);
  color: var(--color-text-faint);
}

/* Hero visual: conditions card */
.hero__visual {
  position: relative;
}

.conditions-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: var(--space-6);
  position: relative;
}

.conditions-card__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: var(--space-5);
  padding-bottom: var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

.conditions-card__loc {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-md);
}

.conditions-card__tag {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  font-variant-numeric: tabular-nums;
}

.conditions-row {
  display: flex;
  justify-content: space-between;
  padding-block: var(--space-3);
  font-size: var(--text-sm);
  border-bottom: 1px solid var(--color-border);
}
.conditions-row:last-child { border-bottom: none; }

.conditions-row__label { color: var(--color-text-muted); }
.conditions-row__value { font-weight: 600; font-variant-numeric: tabular-nums; }
.conditions-row__value.is-accent { color: var(--color-primary); }

.conditions-card__footer {
  margin-top: var(--space-5);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.conditions-card__footer svg { width: 14px; height: 14px; flex-shrink: 0; color: var(--color-accent); }

/* =========================================================
   Problem section
   ========================================================= */
.problem {
  padding-block: clamp(3rem, 7vw, 5.5rem);
  background: var(--color-surface-alt);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.problem__grid {
  display: grid;
  grid-template-columns: 0.7fr 1.3fr;
  gap: clamp(2rem, 5vw, 3.5rem);
}

.problem h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-xl);
  line-height: 1.2;
  letter-spacing: -0.01em;
  position: sticky;
  top: 6rem;
}

.problem__body p {
  font-size: var(--text-md);
  line-height: 1.65;
  color: var(--color-text-muted);
}

.problem__body p + p { margin-top: var(--space-5); }

.problem__body strong {
  color: var(--color-text);
  font-weight: 600;
}

/* =========================================================
   Proof section
   ========================================================= */
.proof {
  padding-block: clamp(3.5rem, 8vw, 6rem);
}

.proof__head {
  text-align: left;
  max-width: 46ch;
  margin-bottom: var(--space-7);
}

.proof__eyebrow {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
  display: block;
}

.proof h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-xl);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-3);
}

.proof__lede {
  color: var(--color-text-muted);
  font-size: var(--text-md);
  max-width: 60ch;
}

.exchange-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-6);
  align-items: start;
}

@media (max-width: 860px) {
  .exchange-grid {
    grid-template-columns: 1fr;
  }
}

.exchange {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}

.exchange__label {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-sm);
  letter-spacing: -0.01em;
  padding: var(--space-4) clamp(1.5rem, 4vw, 2.5rem);
  background: var(--color-surface-alt);
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text);
}

.exchange__msg {
  padding: clamp(1.5rem, 4vw, 2.5rem);
}

.exchange__msg + .exchange__msg {
  border-top: 1px solid var(--color-border);
}

.exchange__who {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: var(--space-4);
}

.exchange__who .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.exchange__msg--user .dot { background: var(--color-text-faint); }
.exchange__msg--user .exchange__who { color: var(--color-text-faint); }

.exchange__msg--coach { background: color-mix(in oklch, var(--color-primary) 6%, var(--color-surface)); }
.exchange__msg--coach .dot { background: var(--color-primary); }
.exchange__msg--coach .exchange__who { color: var(--color-primary); }

.exchange__text {
  font-size: var(--text-md);
  line-height: 1.6;
  color: var(--color-text);
}

.exchange__msg--user .exchange__text {
  color: var(--color-text-muted);
  font-style: italic;
}

.exchange__tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-5);
}

.exchange__tag {
  font-size: var(--text-xs);
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  background: var(--color-surface-alt);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
}

.disclaimer {
  margin-top: var(--space-6);
  padding: var(--space-5) var(--space-6);
  border-radius: var(--radius-md);
  background: color-mix(in oklch, var(--color-accent) 10%, var(--color-surface));
  border: 1px solid color-mix(in oklch, var(--color-accent) 35%, var(--color-border));
}

.disclaimer p {
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text);
  font-style: italic;
}

/* =========================================================
   CTA section
   ========================================================= */
.cta {
  padding-block: clamp(3.5rem, 8vw, 6rem);
  background: var(--color-cta-bg);
  color: var(--color-on-cta);
  border-radius: var(--radius-xl);
  margin-inline: clamp(1.25rem, 4vw, 2.5rem);
  margin-bottom: clamp(3rem, 7vw, 5rem);
}

.cta__inner {
  max-width: 640px;
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 4vw, 2.5rem);
  text-align: center;
}

.cta h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-xl);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-4);
}

.cta p {
  font-size: var(--text-md);
  line-height: 1.6;
  color: color-mix(in oklch, var(--color-on-cta) 82%, transparent);
  max-width: 48ch;
  margin-inline: auto;
}

.signup-form {
  margin-top: var(--space-7);
  display: flex;
  gap: var(--space-3);
  max-width: 460px;
  margin-inline: auto;
  flex-wrap: wrap;
  justify-content: center;
}

.signup-form__field {
  flex: 1;
  min-width: 220px;
  text-align: left;
}

.signup-form label {
  display: block;
  font-size: var(--text-xs);
  font-weight: 600;
  margin-bottom: var(--space-2);
  color: color-mix(in oklch, var(--color-on-cta) 85%, transparent);
}

.signup-form input[type="email"] {
  width: 100%;
  padding: 0.85rem 1rem;
  border-radius: var(--radius-md);
  border: 1px solid color-mix(in oklch, var(--color-on-cta) 35%, transparent);
  background: color-mix(in oklch, var(--color-cta-bg) 85%, black 8%);
  color: var(--color-on-cta);
  font-size: var(--text-base);
  min-height: 48px;
}

.signup-form input[type="email"]::placeholder {
  color: color-mix(in oklch, var(--color-on-cta) 55%, transparent);
}

.signup-form button {
  align-self: flex-end;
  min-height: 48px;
}

.cta__micro {
  margin-top: var(--space-5);
  font-size: var(--text-sm);
  color: color-mix(in oklch, var(--color-on-cta) 70%, transparent);
}

.form-success {
  margin-top: var(--space-6);
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-md);
  background: color-mix(in oklch, var(--color-cta-bg) 88%, black 4%);
  border: 1px solid color-mix(in oklch, var(--color-on-cta) 30%, transparent);
  font-size: var(--text-sm);
  font-weight: 600;
  display: none;
}
.form-success.is-visible { display: block; }

/* =========================================================
   Footer
   ========================================================= */
.site-footer {
  padding-block: var(--space-6);
  border-top: 1px solid var(--color-border);
}

.site-footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-4);
  flex-wrap: wrap;
  font-size: var(--text-sm);
  color: var(--color-text-faint);
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 0.5rem 0.85rem;
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  min-height: 44px;
}
.theme-toggle:hover { border-color: var(--color-border-strong); }
.theme-toggle svg { width: 16px; height: 16px; }

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 860px) {
  .hero__grid { grid-template-columns: 1fr; }
  .hero__visual { max-width: 460px; margin-top: var(--space-6); }
  .problem__grid { grid-template-columns: 1fr; }
  .problem h2 { position: static; }
}

@media (max-width: 560px) {
  .hero h1 { max-width: none; }
  .signup-form { flex-direction: column; align-items: stretch; }
  .signup-form button { align-self: stretch; }
  .cta { margin-inline: var(--space-3); border-radius: var(--radius-lg); }
  .site-footer__inner { flex-direction: column; align-items: flex-start; }
}