/* =============================================
   PRESENCE — Landing Page Styles
   ============================================= */

/* --- Design Tokens --- */
:root,
[data-theme='light'] {
  --color-bg: #f7f6f2;
  --color-surface: #f0ede8;
  --color-border: #d4d1ca;
  --color-text: #1a1916;
  --color-text-muted: #7a7974;
  --color-text-faint: #b0afa9;
  --color-accent: #1a1916;
  --color-accent-hover: #3a3834;
  --color-dot-on: #1a1916;
  --color-dot-dim: #d4d1ca;
  --color-input-bg: #fff;
  --color-input-border: #c8c5be;
  --color-input-border-focus: #1a1916;
  --shadow-btn: 0 2px 8px rgba(0,0,0,0.12);
  --shadow-btn-hover: 0 4px 16px rgba(0,0,0,0.18);
  --transition: 180ms cubic-bezier(0.16, 1, 0.3, 1);
  --font-display: 'DM Sans', 'Helvetica Neue', sans-serif;
  --font-body: 'DM Sans', 'Helvetica Neue', sans-serif;
  --font-mono: 'DM Mono', 'Courier New', monospace;
}

[data-theme='dark'] {
  --color-bg: #101010;
  --color-surface: #181816;
  --color-border: #2a2926;
  --color-text: #e8e6e1;
  --color-text-muted: #797876;
  --color-text-faint: #424140;
  --color-accent: #e8e6e1;
  --color-accent-hover: #fff;
  --color-dot-on: #e8e6e1;
  --color-dot-dim: #2e2d2b;
  --color-input-bg: #181816;
  --color-input-border: #2e2d2b;
  --color-input-border-focus: #e8e6e1;
  --shadow-btn: 0 2px 8px rgba(0,0,0,0.4);
  --shadow-btn-hover: 0 4px 20px rgba(0,0,0,0.6);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg: #101010;
    --color-surface: #181816;
    --color-border: #2a2926;
    --color-text: #e8e6e1;
    --color-text-muted: #797876;
    --color-text-faint: #424140;
    --color-accent: #e8e6e1;
    --color-accent-hover: #fff;
    --color-dot-on: #e8e6e1;
    --color-dot-dim: #2e2d2b;
    --color-input-bg: #181816;
    --color-input-border: #2e2d2b;
    --color-input-border-focus: #e8e6e1;
    --shadow-btn: 0 2px 8px rgba(0,0,0,0.4);
    --shadow-btn-hover: 0 4px 20px rgba(0,0,0,0.6);
  }
}

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

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  min-height: 100dvh;
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  line-height: 1.6;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition), color var(--transition);
}

img, svg { display: block; max-width: 100%; }
button { cursor: pointer; background: none; border: none; font: inherit; color: inherit; }
input, button, textarea, select { font: inherit; color: inherit; }
h1, h2, h3, h4 { text-wrap: balance; line-height: 1.1; }
p, li { text-wrap: pretty; }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0;
  margin: -1px; overflow: hidden; clip: rect(0,0,0,0);
  white-space: nowrap; border-width: 0;
}

:focus-visible {
  outline: 2px solid var(--color-text);
  outline-offset: 3px;
  border-radius: 3px;
}

/* --- Header --- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 2rem;
  background: color-mix(in srgb, var(--color-bg) 88%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), background var(--transition);
}

.site-header.scrolled {
  border-bottom-color: var(--color-border);
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--color-text);
}

.logo-svg {
  width: 28px;
  height: 35px;
  flex-shrink: 0;
  transition: opacity var(--transition);
}

.logo-svg .dot-on {
  fill: var(--color-dot-on);
  opacity: 1;
}

.logo-svg .dot-dim {
  fill: var(--color-dot-dim);
  opacity: 1;
}

.logo-wordmark {
  font-family: var(--font-display);
  font-size: 1.0625rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  color: var(--color-text);
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  color: var(--color-text-muted);
  transition: color var(--transition), background var(--transition);
}

.theme-toggle:hover {
  color: var(--color-text);
  background: color-mix(in srgb, var(--color-text) 8%, transparent);
}

/* --- Hero --- */
.hero {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100dvh;
  padding: 7rem 2rem 4rem;
}

.hero-inner {
  max-width: 600px;
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

/* Eyebrow */
.eyebrow {
  font-family: var(--font-mono);
  font-size: clamp(0.6875rem, 0.65rem + 0.2vw, 0.8125rem);
  font-weight: 400;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

/* Headline */
.headline {
  font-family: var(--font-display);
  font-size: clamp(2.25rem, 1.5rem + 3vw, 4rem);
  font-weight: 300;
  letter-spacing: -0.03em;
  line-height: 1.08;
  color: var(--color-text);
}

.headline-accent {
  font-style: italic;
  font-weight: 300;
  color: var(--color-text);
}

/* Subline */
.subline {
  font-size: clamp(1rem, 0.9rem + 0.4vw, 1.125rem);
  font-weight: 400;
  color: var(--color-text-muted);
  line-height: 1.65;
  max-width: 52ch;
}

/* --- Email Form --- */
.email-form {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  margin-top: 0.5rem;
}

.input-group {
  display: flex;
  align-items: stretch;
  gap: 0;
  border: 1px solid var(--color-input-border);
  border-radius: 6px;
  background: var(--color-input-bg);
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.input-group:focus-within {
  border-color: var(--color-input-border-focus);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-text) 10%, transparent);
  outline: none;
}

.input-group input[type="email"] {
  flex: 1;
  padding: 0.75rem 1rem;
  background: transparent;
  border: none;
  outline: none;
  font-size: clamp(0.9rem, 0.875rem + 0.15vw, 1rem);
  color: var(--color-text);
  min-width: 0;
}

.input-group input[type="email"]::placeholder {
  color: var(--color-text-faint);
}

.btn-submit {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.75rem 1.25rem;
  background: var(--color-accent);
  color: var(--color-bg);
  font-size: clamp(0.8125rem, 0.78rem + 0.15vw, 0.9375rem);
  font-weight: 500;
  letter-spacing: 0.01em;
  border-left: 1px solid var(--color-input-border);
  white-space: nowrap;
  flex-shrink: 0;
  transition: background var(--transition), opacity var(--transition);
}

.btn-submit:hover {
  background: var(--color-accent-hover);
  opacity: 0.92;
}

.btn-icon {
  transition: transform var(--transition);
}

.btn-submit:hover .btn-icon {
  transform: translateX(2px);
}

.form-hint {
  font-size: clamp(0.6875rem, 0.65rem + 0.15vw, 0.8125rem);
  color: var(--color-text-faint);
  padding-left: 0.25rem;
}

/* Success state */
.email-form.success .input-group {
  display: none;
}

.success-msg {
  display: none;
  padding: 0.875rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  letter-spacing: 0.01em;
}

.email-form.success .success-msg {
  display: block;
}

/* --- Footer --- */
.site-footer {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.625rem;
  padding: 1.5rem 2rem;
  font-size: clamp(0.6875rem, 0.65rem + 0.15vw, 0.8125rem);
  color: var(--color-text-faint);
  font-family: var(--font-mono);
  border-top: 1px solid var(--color-border);
}

.footer-link {
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color var(--transition);
}

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

/* --- Grain overlay (subtle texture) --- */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0.022;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-size: 256px 256px;
}

header, main, footer { position: relative; z-index: 1; }

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

.eyebrow    { animation: fadeUp 0.55s cubic-bezier(0.16,1,0.3,1) 0.05s both; }
.headline   { animation: fadeUp 0.65s cubic-bezier(0.16,1,0.3,1) 0.15s both; }
.subline    { animation: fadeUp 0.65s cubic-bezier(0.16,1,0.3,1) 0.25s both; }
.email-form { animation: fadeUp 0.65s cubic-bezier(0.16,1,0.3,1) 0.35s both; }

@media (prefers-reduced-motion: reduce) {
  .eyebrow, .headline, .subline, .email-form { animation: none; }
}

/* --- Responsive --- */
@media (max-width: 520px) {
  .site-header { padding: 1rem 1.25rem; }
  .hero { padding: 6rem 1.25rem 3rem; }
  .site-footer { padding: 1.25rem; gap: 0.5rem; }

  .input-group {
    flex-direction: column;
  }

  .btn-submit {
    justify-content: center;
    border-left: none;
    border-top: 1px solid var(--color-input-border);
    padding: 0.75rem 1rem;
  }
}