/* =============================================================
   AI.JBHerrera — base.css
   Shared design system. Apple-inspired, light-default with dark toggle.
   See /docs/design-standard.md for the full standard.
   ============================================================= */

/* ── Tokens ── */
:root {
  /* Brand */
  --color-primary: #667eea;
  --color-primary-hover: #5a67d8;
  --color-secondary: #764ba2;
  --gradient-brand: linear-gradient(135deg, #667eea 0%, #764ba2 100%);

  /* Status */
  --color-success: #34c759;
  --color-warning: #ff9500;
  --color-danger:  #ff3b30;
  --color-info:    #007aff;

  /* Light surface (default) */
  --color-bg:           #ffffff;
  --color-bg-secondary: #f5f5f7;
  --color-surface:      #ffffff;
  --color-surface-hover:#fafafa;
  --color-text:         #1d1d1f;
  --color-text-secondary:#6e6e73;
  --color-text-tertiary:#86868b;
  --color-border:       #d2d2d7;
  --color-border-subtle:#e8e8ed;
  --color-overlay:      rgba(255,255,255,0.72);
  --color-primary-soft: rgba(102,126,234,0.10);

  /* Shadow (Apple-soft) */
  --shadow-xs: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.05);
  --shadow-md: 0 6px 20px rgba(0,0,0,0.08);
  --shadow-lg: 0 16px 40px rgba(0,0,0,0.10);

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 28px;
  --radius-full: 9999px;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Inter', 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, 'SF Mono', Menlo, Monaco, monospace;

  /* Spacing */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-8: 48px;
  --space-10: 64px;
  --space-12: 96px;

  /* Motion */
  --ease-out: cubic-bezier(0.32, 0.72, 0, 1);
  --duration-fast: 150ms;
  --duration-base: 250ms;
  --duration-slow: 400ms;

  /* Layout */
  --nav-height: 56px;
  --container-max: 1200px;
  --content-max: 800px;
}

[data-theme="dark"] {
  --color-bg:           #000000;
  --color-bg-secondary: #1c1c1e;
  --color-surface:      #1c1c1e;
  --color-surface-hover:#2c2c2e;
  --color-text:         #f5f5f7;
  --color-text-secondary:#a1a1a6;
  --color-text-tertiary:#6e6e73;
  --color-border:       #38383a;
  --color-border-subtle:#2c2c2e;
  --color-overlay:      rgba(0,0,0,0.72);
  --color-primary-soft: rgba(102,126,234,0.18);

  --shadow-xs: 0 1px 2px rgba(0,0,0,0.4);
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.4);
  --shadow-md: 0 6px 20px rgba(0,0,0,0.6);
  --shadow-lg: 0 16px 40px rgba(0,0,0,0.7);
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.47;
  background: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background var(--duration-base) var(--ease-out), color var(--duration-base) var(--ease-out);
}
a { color: var(--color-primary); text-decoration: none; }
a:hover { color: var(--color-primary-hover); }
img, svg { display: block; max-width: 100%; }
button { font-family: inherit; }

/* ── Type scale ── */
.text-display { font-size: clamp(40px, 6vw, 56px); font-weight: 600; line-height: 1.07; letter-spacing: -0.022em; }
.text-h1      { font-size: clamp(32px, 4vw, 40px); font-weight: 600; line-height: 1.1;  letter-spacing: -0.02em; }
.text-h2      { font-size: clamp(24px, 3vw, 32px); font-weight: 600; line-height: 1.2;  letter-spacing: -0.015em; }
.text-h3      { font-size: 20px; font-weight: 600; line-height: 1.3; letter-spacing: -0.01em; }
.text-body    { font-size: 17px; font-weight: 400; line-height: 1.47; }
.text-body-sm { font-size: 15px; font-weight: 400; line-height: 1.45; }
.text-caption { font-size: 13px; font-weight: 400; line-height: 1.4;  color: var(--color-text-secondary); }
.text-eyebrow {
  font-size: 12px; font-weight: 600; line-height: 1.3;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--color-text-secondary);
}
.text-muted { color: var(--color-text-secondary); }

/* ── Layout ── */
.container        { max-width: var(--container-max); margin: 0 auto; padding: 0 var(--space-5); }
.container-narrow { max-width: var(--content-max);   margin: 0 auto; padding: 0 var(--space-5); }
.section          { padding: var(--space-10) 0; }
.section-tight    { padding: var(--space-8) 0; }
.section-header   { text-align: center; margin: 0 auto var(--space-8); max-width: var(--content-max); padding: 0 var(--space-5); }
.section-header > * + * { margin-top: var(--space-3); }

/* ── Navbar ── */
.navbar {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  height: var(--nav-height); padding: 0 var(--space-5);
  background: var(--color-overlay);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--color-border-subtle);
}
.navbar-brand {
  display: inline-flex; align-items: center; gap: var(--space-2);
  color: var(--color-text); text-decoration: none;
  font-weight: 600; font-size: 15px; letter-spacing: -0.01em;
}
.navbar-brand:hover { color: var(--color-text); }
.navbar-brand svg { width: 22px; height: 22px; color: var(--color-primary); }

.navbar-links { display: flex; gap: 2px; align-items: center; }
.navbar-link {
  padding: 8px 14px; border-radius: var(--radius-sm);
  color: var(--color-text-secondary); text-decoration: none;
  font-size: 14px; font-weight: 500;
  transition: color var(--duration-fast) var(--ease-out), background var(--duration-fast) var(--ease-out);
}
.navbar-link:hover { color: var(--color-text); background: var(--color-bg-secondary); }
.navbar-link.active { color: var(--color-primary); }

@media (max-width: 640px) {
  .navbar-links .navbar-link:not(.active) { display: none; }
}

/* ── Theme toggle ── */
.theme-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  width: 34px; height: 34px; margin-left: 4px;
  background: transparent; border: none; cursor: pointer;
  color: var(--color-text-secondary);
  border-radius: var(--radius-full);
  transition: color var(--duration-fast), background var(--duration-fast);
}
.theme-toggle:hover { color: var(--color-text); background: var(--color-bg-secondary); }
.theme-toggle svg { width: 18px; height: 18px; }
.theme-toggle .icon-sun { display: none; }
[data-theme="dark"] .theme-toggle .icon-sun  { display: block; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

/* ── Buttons ── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 22px; border-radius: var(--radius-full);
  font-family: inherit; font-size: 15px; font-weight: 500;
  text-decoration: none; cursor: pointer; border: none; white-space: nowrap;
  transition: background var(--duration-fast) var(--ease-out),
              color var(--duration-fast) var(--ease-out),
              transform var(--duration-fast) var(--ease-out),
              box-shadow var(--duration-fast) var(--ease-out);
}
.btn:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; }
.btn-primary  { background: var(--color-primary); color: #fff; }
.btn-primary:hover  { background: var(--color-primary-hover); color: #fff; transform: translateY(-1px); box-shadow: var(--shadow-sm); }
.btn-secondary { background: var(--color-bg-secondary); color: var(--color-text); }
.btn-secondary:hover { background: var(--color-border-subtle); color: var(--color-text); }
.btn-ghost    { background: transparent; color: var(--color-primary); }
.btn-ghost:hover    { background: var(--color-primary-soft); color: var(--color-primary); }
.btn-success { background: var(--color-success); color: #fff; }
.btn-success:hover { background: #2aa84d; color: #fff; transform: translateY(-1px); box-shadow: var(--shadow-sm); }
.btn-warning { background: var(--color-warning); color: #fff; }
.btn-warning:hover { background: #d97706; color: #fff; transform: translateY(-1px); box-shadow: var(--shadow-sm); }
.btn-danger  { background: var(--color-danger); color: #fff; }
.btn-danger:hover  { background: #d92d22; color: #fff; transform: translateY(-1px); box-shadow: var(--shadow-sm); }
.btn-outline {
  background: var(--color-surface); color: var(--color-text);
  border: 1px solid var(--color-border);
}
.btn-outline:hover { background: var(--color-bg-secondary); color: var(--color-text); border-color: var(--color-border); }
.btn-lg { padding: 14px 28px; font-size: 16px; }
.btn-sm { padding: 6px 14px;  font-size: 13px; }

/* ── Cards ── */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: border-color var(--duration-base) var(--ease-out),
              box-shadow var(--duration-base) var(--ease-out),
              transform var(--duration-base) var(--ease-out);
}
.card-interactive {
  display: block; text-decoration: none; color: inherit; cursor: pointer;
}
.card-interactive:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-border);
  color: inherit;
}

/* ── Form controls ── */
.label {
  display: block; font-size: 13px; font-weight: 500;
  color: var(--color-text-secondary); margin-bottom: 6px;
}
.input, .select, .textarea {
  width: 100%; padding: 10px 14px;
  background: var(--color-surface); color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-family: inherit; font-size: 15px; line-height: 1.4;
  transition: border-color var(--duration-fast), box-shadow var(--duration-fast);
}
.input::placeholder, .textarea::placeholder { color: var(--color-text-tertiary); }
.input:focus, .select:focus, .textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}
.textarea { min-height: 100px; resize: vertical; }

/* ── Badges & tags ── */
.badge {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 10px; border-radius: var(--radius-full);
  font-size: 12px; font-weight: 600; line-height: 1;
}
.badge-success { background: rgba(52,199,89,0.14);  color: #1f8a3d; }
[data-theme="dark"] .badge-success { color: #6ee49a; }
.badge-warning { background: rgba(255,149,0,0.14);  color: #b86b00; }
[data-theme="dark"] .badge-warning { color: #ffb24d; }
.badge-info    { background: rgba(0,122,255,0.14);  color: #0058b8; }
[data-theme="dark"] .badge-info    { color: #6ab0ff; }
.badge-neutral { background: var(--color-bg-secondary); color: var(--color-text-secondary); }
.badge-dot { width: 6px; height: 6px; border-radius: 50%; background: currentColor; }

.tag {
  display: inline-block;
  padding: 4px 10px; border-radius: var(--radius-sm);
  background: var(--color-bg-secondary); color: var(--color-text-secondary);
  font-size: 12px; font-weight: 500;
}

/* ── Hero ── */
.hero {
  text-align: center;
  padding: var(--space-12) var(--space-5) var(--space-10);
  max-width: 860px; margin: 0 auto;
}
.hero-tag {
  display: inline-block;
  padding: 6px 14px;
  background: var(--color-primary-soft); color: var(--color-primary);
  border-radius: var(--radius-full);
  font-size: 12px; font-weight: 600; letter-spacing: 0.05em;
  text-transform: uppercase; margin-bottom: var(--space-5);
}
.hero h1 { margin-bottom: var(--space-4); }
.hero p  { color: var(--color-text-secondary); font-size: 19px; max-width: 620px; margin: 0 auto; line-height: 1.5; }

/* ── Toast ── */
.toast {
  position: fixed; bottom: 24px; right: 24px; z-index: 200;
  padding: 12px 18px; border-radius: var(--radius-md);
  color: #fff; font-size: 14px; font-weight: 500;
  opacity: 0; pointer-events: none;
  box-shadow: var(--shadow-lg);
  max-width: 400px;
  transform: translateY(8px);
  transition: opacity var(--duration-base) var(--ease-out), transform var(--duration-base) var(--ease-out);
}
.toast.show { opacity: 1; transform: translateY(0); pointer-events: auto; }
.toast.success { background: var(--color-success); }
.toast.error   { background: var(--color-danger); }
.toast.info    { background: var(--color-info); }

/* ── Modal overlay ── */
.modal-overlay {
  display: none; position: fixed; inset: 0; z-index: 100;
  background: rgba(0,0,0,0.5);
  justify-content: center; align-items: center;
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}
.modal-overlay.active { display: flex; }
.modal-overlay > .modal {
  background: var(--color-surface);
  color: var(--color-text);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  width: 90%; max-width: 600px;
  max-height: 80vh; overflow-y: auto;
  box-shadow: var(--shadow-lg);
}

/* ── Footer ── */
.site-footer {
  border-top: 1px solid var(--color-border-subtle);
  padding: var(--space-8) var(--space-5);
  text-align: center;
  color: var(--color-text-tertiary);
  font-size: 13px;
}
.site-footer a { color: var(--color-text-secondary); text-decoration: none; }
.site-footer a:hover { color: var(--color-text); }

/* ── Reduced motion ── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}