/* ==========================================================================
   Style 09 — Mountain Serenity
   Rehab Website Factory

   A solid, grounded aesthetic with slate grays, forest greens, and cool
   teals. Represents stability, quiet strength, and enduring peace.

   Modernized: CSS Nesting, Container Queries, :has(), clamp(),
   @layer, oklch(), color-mix(), scroll-driven animations,
   view transitions, dark mode
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@400;600;700&family=Source+Sans+Pro:wght@400;600;700&display=swap');

/* --------------------------------------------------------------------------
   Cascade Layers
   -------------------------------------------------------------------------- */
@layer theme, base, components, utilities;

/* --------------------------------------------------------------------------
   Custom Properties Override
   -------------------------------------------------------------------------- */
@layer theme {
  :root {
    /* Colors — oklch */
    --color-primary: oklch(0.42 0.03 250);
    --color-primary-rgb: 74, 85, 104;
    --color-secondary: oklch(0.42 0.04 150);
    --color-secondary-rgb: 72, 98, 77;
    --color-accent: oklch(0.76 0.04 190);
    --color-accent-rgb: 157, 195, 193;
    --color-text: oklch(0.18 0.02 250);
    --color-text-light: #718096;
    --color-text-inverse: #F7F8F9;
    --color-bg: #F7F8F9;
    --color-bg-alt: #FFFFFF;
    --color-bg-dark: oklch(0.18 0.02 250);
    --color-border: #CBD5E0;

    /* Typography */
    --font-heading: 'Montserrat', sans-serif;
    --font-body: 'Source Sans Pro', sans-serif;
    --font-weight-light: 400;
    --font-weight-normal: 400;
    --font-weight-medium: 600;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    /* Fluid spacing */
    --space-xs: clamp(0.25rem, 0.5vw, 0.5rem);
    --space-sm: clamp(0.5rem, 1vw, 1rem);
    --space-md: clamp(1rem, 2vw, 2rem);
    --space-lg: clamp(1.5rem, 3vw, 3rem);
    --space-xl: clamp(2rem, 5vw, 5rem);

    /* Border Radius — controlled, sturdy */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 8px;

    /* Shadows — subtle, grounding */
    --shadow-sm: 0 1px 3px rgba(26, 32, 44, 0.06);
    --shadow-md: 0 4px 12px rgba(26, 32, 44, 0.08);
    --shadow-lg: 0 8px 24px rgba(26, 32, 44, 0.1);
    --shadow-xl: 0 16px 40px rgba(26, 32, 44, 0.14);

    /* Hero Overlay */
    --hero-overlay: linear-gradient(
      180deg,
      oklch(0.42 0.03 250 / 0.7) 0%,
      oklch(0.18 0.02 250 / 0.6) 100%
    );

    /* Transitions */
    --transition-fast: 0.12s ease;
    --transition-base: 0.25s ease;
    --transition-slow: 0.45s ease;
  }

  /* --------------------------------------------------------------------------
     Dark Mode
     -------------------------------------------------------------------------- */
  @media (prefers-color-scheme: dark) {
    :root {
      --color-primary: oklch(0.60 0.03 250);
      --color-secondary: oklch(0.55 0.04 150);
      --color-accent: oklch(0.70 0.04 190);
      --color-text: oklch(0.88 0.01 250);
      --color-text-light: oklch(0.62 0.02 250);
      --color-text-inverse: #0F1218;
      --color-bg: oklch(0.14 0.02 250);
      --color-bg-alt: oklch(0.18 0.02 250);
      --color-bg-dark: oklch(0.10 0.02 250);
      --color-border: oklch(0.32 0.02 250);

      --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.35);
      --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
      --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.45);
      --shadow-xl: 0 16px 40px rgba(0, 0, 0, 0.55);

      --hero-overlay: linear-gradient(
        180deg,
        oklch(0.12 0.02 250 / 0.85) 0%,
        oklch(0.06 0.02 250 / 0.8) 100%
      );
    }
  }
}

/* --------------------------------------------------------------------------
   Base Styles
   -------------------------------------------------------------------------- */
@layer base {
  body {
    background-color: var(--color-bg);
    view-transition-name: page-body;
  }

  h1, h2, h3 {
    letter-spacing: -0.02em;
    font-weight: var(--font-weight-bold);
  }

  h1 {
    color: var(--color-text);
    font-size: clamp(2rem, 5vw, 3.5rem);
  }

  h2 {
    color: var(--color-primary);
    font-size: clamp(1.5rem, 3.5vw, 2.5rem);

    &::after {
      content: '';
      display: block;
      width: clamp(40px, 8vw, 80px);
      height: 3px;
      background: var(--color-accent);
      margin-top: var(--space-xs);
      opacity: 0.8;
    }
  }

  h3 {
    font-weight: var(--font-weight-medium);
    font-size: clamp(1.15rem, 2.5vw, 1.75rem);
  }

  hr {
    border: none;
    border-top: 2px solid var(--color-border);
    opacity: 0.5;
  }

  ::selection {
    background: color-mix(in oklch, var(--color-accent) 30%, transparent);
    color: var(--color-text);
  }
}

/* --------------------------------------------------------------------------
   Component Styles
   -------------------------------------------------------------------------- */
@layer components {
  /* Sections */
  .section--alt {
    background-color: var(--color-bg-alt);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
    container-type: inline-size;
  }

  .cta-section.section--alt {
    background-color: var(--color-primary);
    background-image: none;
    color: var(--color-text-inverse);
  }

  .section--dark {
    background: var(--color-bg-dark);
    color: var(--color-text-inverse);
    background-image:
      linear-gradient(180deg, oklch(0.18 0.02 250) 0%, oklch(0.22 0.02 255) 100%);

    &::before {
      border-top: 1px solid color-mix(in oklch, var(--color-accent) 8%, transparent);
    }

    &::after {
      border-bottom: 1px solid color-mix(in oklch, var(--color-accent) 8%, transparent);
    }
  }

  /* Cards — container queries + nesting */
  .card,
  .program-card,
  .contact-card,
  .blog-card,
  .nav-card,
  .sidebar-widget {
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--transition-base), transform var(--transition-base);
    container-type: inline-size;
    view-transition-name: card;

    &:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-2px);
    }
  }

  /* Subtle left accent bar */
  .card::before,
  .card, .program-card, .contact-card, .blog-card::before {
    border-left: 3px solid var(--color-secondary);
    border-radius: var(--radius-md) 0 0 var(--radius-md);
    opacity: 0.4;
    transition: opacity var(--transition-base);
  }

  .card:hover::before,
  .card, .program-card, .contact-card, .blog-card:hover::before {
    opacity: 0.8;
  }

  @container (max-width: 300px) {
    .card, .program-card, .blog-card {
      padding: var(--space-sm);
    }
  }

  @container (min-width: 500px) {
    .card, .program-card, .blog-card {
      padding: var(--space-md);
    }
  }

  /* :has() contextual styling */
  section:has(.card) {
    padding-block: var(--space-lg);
  }

  .hero:has(video) {
    min-height: 80vh;
  }

  .card:has(img) {
    overflow: hidden;
  }

  /* Buttons — nesting */
  .btn,
  .btn-primary,
  .btn-secondary,
  .btn-outline,
  .btn--phone {
    border-radius: var(--radius-md);
    font-family: var(--font-heading);
    font-weight: var(--font-weight-medium);
    letter-spacing: 0.03em;
    text-transform: uppercase;
    font-size: clamp(0.75em, 1vw, 0.85em);
    transition: all var(--transition-base);
    padding: clamp(0.5rem, 1.2vw, 0.85rem) clamp(1rem, 2.5vw, 2rem);
  }

  .btn-primary,
  .button--primary {
    background: var(--color-primary);
    color: var(--color-text-inverse);
    border-color: var(--color-primary);
    box-shadow: 0 2px 6px rgba(var(--color-primary-rgb), 0.2);

    &:hover {
      background: color-mix(in oklch, var(--color-primary) 85%, black);
      box-shadow: 0 4px 12px rgba(var(--color-primary-rgb), 0.3);
      transform: translateY(-1px);
    }
  }

  .btn-secondary,
  .button--secondary {
    background: transparent;
    color: var(--color-primary);
    border: 2px solid var(--color-primary);

    &:hover {
      background: color-mix(in oklch, var(--color-primary) 5%, transparent);
    }
  }

  .btn-accent,
  .button--accent {
    background: var(--color-accent);
    color: var(--color-text);
    border-color: var(--color-accent);

    &:hover {
      background: color-mix(in oklch, var(--color-accent) 85%, black);
    }
  }

  /* Navigation — nesting */
  .site-header {
    background: var(--color-bg);
    border-bottom: 2px solid var(--color-border);
    view-transition-name: header;
  }

  .tab-bar {
    background: var(--color-bg-alt, var(--color-bg));
    border-bottom: 1px solid var(--color-border);
  }

  .main-nav a, .mega-nav a, .nav-links a {
    font-family: var(--font-heading);
    font-weight: var(--font-weight-medium);
    font-size: 0.85em;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-light);
    transition: color var(--transition-fast);

    &:hover {
      color: var(--color-text);
    }

    &.active {
      color: var(--color-text);
      font-weight: var(--font-weight-bold);
      border-bottom: 2px solid var(--color-secondary);
    }
  }

  .nav-item.active > a {
    color: var(--color-text);
    font-weight: var(--font-weight-bold);
    border-bottom: 2px solid var(--color-secondary);
  }

  /* Forms — nesting */
  input,
  textarea,
  select {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    background: var(--color-bg-alt);
    color: var(--color-text);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    padding: clamp(0.5rem, 1vw, 0.75rem) clamp(0.75rem, 1.5vw, 1rem);

    &:focus {
      border-color: var(--color-primary);
      box-shadow: 0 0 0 3px color-mix(in oklch, var(--color-primary) 10%, transparent);
      outline: none;
    }
  }

  /* Footer — nesting */
  .footer,
  footer {
    background: var(--color-bg-dark);
    color: color-mix(in oklch, var(--color-text-inverse) 90%, transparent);
    border-top: 3px solid var(--color-secondary);
    view-transition-name: footer;

    & h3 {
      color: #FFFFFF;
    }

    & a {
      color: color-mix(in oklch, var(--color-text-inverse) 80%, transparent);
      transition: color var(--transition-fast);

      &:hover {
        color: var(--color-accent);
      }
    }
  }

  /* Testimonials */
  blockquote,
  .testimonial,
  .testimonials-grid blockquote {
    padding: var(--space-sm) var(--space-md);
    border-left: 4px solid var(--color-secondary);
    background: color-mix(in oklch, var(--color-secondary) 4%, transparent);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    font-style: italic;
    color: var(--color-text);
  }

  /* Badges */
  .badge,
  .tag {
    background: color-mix(in oklch, var(--color-primary) 8%, transparent);
    color: var(--color-primary);
    border-radius: var(--radius-sm);
    font-family: var(--font-heading);
    font-weight: var(--font-weight-medium);
    font-size: 0.8em;
    text-transform: uppercase;
    letter-spacing: 0.05em;
  }

  /* Landscape lines decorative class */
  .landscape-lines,
  .divider {
    background-image:
      linear-gradient(transparent 33%, var(--color-border) 33%, var(--color-border) 34%, transparent 34%),
      linear-gradient(transparent 66%, color-mix(in oklch, var(--color-accent) 30%, transparent) 66%, color-mix(in oklch, var(--color-accent) 30%, transparent) 67%, transparent 67%);
  }

  /* Scrollbar */
  ::-webkit-scrollbar {
    background: var(--color-bg);
  }

  ::-webkit-scrollbar-thumb {
    background: color-mix(in oklch, var(--color-primary) 20%, transparent);
    border-radius: var(--radius-sm);

    &:hover {
      background: color-mix(in oklch, var(--color-primary) 35%, transparent);
    }
  }
}

/* --------------------------------------------------------------------------
   Animations & Scroll-Driven Effects
   -------------------------------------------------------------------------- */
@layer utilities {
  @keyframes mountain-reveal {
    from {
      opacity: 0;
      transform: translateY(10px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  .animate-in,
  [data-animate] {
    animation: mountain-reveal 0.5s ease-out both;
  }

  @supports (animation-timeline: view()) {
    .animate-in,
    [data-animate] {
      animation: mountain-reveal ease-out both;
      animation-timeline: view();
      animation-range: entry 0% entry 25%;
    }

    .hero,
    .page-hero {
      animation: mountain-reveal ease-out both;
      animation-timeline: scroll();
      animation-range: 0% 35%;
    }
  }

  @supports (view-transition-name: none) {
    ::view-transition-old(page-body),
    ::view-transition-new(page-body) {
      animation-duration: 0.25s;
    }

    ::view-transition-old(header),
    ::view-transition-new(header) {
      animation-duration: 0.2s;
    }
  }
}