/* ==========================================================================
   Chapper Digital — style.css
   Single stylesheet, mobile-first, no build tools.
   All design tokens are in :root for easy hand-editing.
   ========================================================================== */

/* ---------- Design Tokens ---------- */
:root {
  /* Colors */
  --color-bg:         #0a0a0a;
  --color-surface:    #111111;
  --color-surface-2:  #1a1a1a;
  --color-border:     #222222;
  --color-text:       #f0f0f0;
  --color-text-muted: #999999;
  --color-accent:     #0066FF;
  --color-accent-light:#4d94ff;
  --color-accent-glow: rgba(0, 102, 255, 0.15);
  --color-white:      #ffffff;

  /* Typography */
  --font-stack: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  --font-mono:  'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;

  --text-xs:   clamp(0.75rem, 0.7rem + 0.25vw, 0.8125rem);
  --text-sm:   clamp(0.8125rem, 0.775rem + 0.25vw, 0.875rem);
  --text-base: clamp(0.9375rem, 0.9rem + 0.25vw, 1rem);
  --text-lg:   clamp(1.125rem, 1rem + 0.5vw, 1.25rem);
  --text-xl:   clamp(1.5rem, 1.2rem + 1vw, 2rem);
  --text-2xl:  clamp(2rem, 1.5rem + 2vw, 3rem);
  --text-3xl:  clamp(2.5rem, 1.8rem + 3vw, 4rem);

  --leading-tight:  1.2;
  --leading-normal: 1.6;

  /* Spacing */
  --space-xs:  0.5rem;
  --space-sm:  0.75rem;
  --space-md:  1rem;
  --space-lg:  1.5rem;
  --space-xl:  2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;
  --space-5xl: 8rem;

  /* Layout */
  --max-width:   1200px;
  --nav-height:  72px;
  --border-radius: 8px;

  /* Transitions */
  --transition-fast:   150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow:   400ms ease;
}


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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-stack);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-accent-light);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-white);
}

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  line-height: var(--leading-tight);
  font-weight: 600;
}


/* ---------- Utility ---------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

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

.accent {
  color: var(--color-accent);
}


/* ---------- Navigation ---------- */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  background: rgba(10, 10, 10, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-brand {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: -0.02em;
}

.nav-brand:hover {
  color: var(--color-white);
}

.nav-links {
  display: none;
  gap: var(--space-xl);
}

.nav-links a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 500;
  padding: var(--space-xs) 0;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--transition-normal);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-white);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

/* Hamburger */
.nav-toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 28px;
  height: 28px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text);
  transition: transform var(--transition-normal), opacity var(--transition-fast);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile menu */
.nav-mobile {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-bg);
  padding: var(--space-2xl) var(--space-lg);
  z-index: 99;
}

.nav-mobile.is-open {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.nav-mobile a {
  font-size: var(--text-xl);
  color: var(--color-text-muted);
  font-weight: 600;
}

.nav-mobile a:hover,
.nav-mobile a.active {
  color: var(--color-white);
}


/* ---------- Hero ---------- */
.hero {
  padding: calc(var(--nav-height) + var(--space-5xl)) 0 var(--space-5xl);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--color-accent-glow) 0%, transparent 70%);
  pointer-events: none;
}

.hero-label {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-accent);
  margin-bottom: var(--space-lg);
}

.hero h1 {
  font-size: var(--text-3xl);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-lg);
  max-width: 720px;
}

.hero p {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 600px;
  margin-bottom: var(--space-2xl);
}


/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm) var(--space-xl);
  font-family: var(--font-stack);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0.02em;
  border-radius: var(--border-radius);
  border: none;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
}

.btn-primary {
  background: var(--color-accent);
  color: var(--color-white);
}

.btn-primary:hover {
  background: var(--color-accent-light);
  color: var(--color-white);
  transform: translateY(-1px);
}

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

.btn-outline:hover {
  border-color: var(--color-accent);
  color: var(--color-white);
  transform: translateY(-1px);
}

.btn-social {
  padding: var(--space-sm) var(--space-lg);
  background: var(--color-surface-2);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  font-size: var(--text-base);
  min-width: 200px;
  justify-content: center;
}

.btn-social:hover {
  border-color: var(--color-accent);
  color: var(--color-white);
  transform: translateY(-1px);
}


/* ---------- Sections ---------- */
.section {
  padding: var(--space-5xl) 0;
}

.section-label {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-accent);
  margin-bottom: var(--space-md);
}

.section-title {
  font-size: var(--text-2xl);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-lg);
}

.section-intro {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 640px;
  margin-bottom: var(--space-3xl);
}


/* ---------- Capability Cards ---------- */
.capabilities-grid {
  display: grid;
  gap: var(--space-lg);
}

.capability-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: var(--space-2xl);
  transition: border-color var(--transition-normal), transform var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.capability-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-normal);
}

.capability-card:hover {
  border-color: var(--color-accent);
  transform: translateY(-2px);
}

.capability-card:hover::before {
  transform: scaleX(1);
}

.capability-card h3 {
  font-size: var(--text-lg);
  margin-bottom: var(--space-md);
}

.capability-card p {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}


/* ---------- Case Studies ---------- */
.case-study {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: var(--space-2xl);
  margin-bottom: var(--space-xl);
  transition: border-color var(--transition-normal);
}

.case-study:hover {
  border-color: var(--color-accent);
}

.case-study-label {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}

.case-study h3 {
  font-size: var(--text-xl);
  margin-bottom: var(--space-md);
}

.case-study p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
}

.case-study-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
}

.case-study-tag {
  font-size: var(--text-xs);
  font-weight: 500;
  padding: var(--space-xs) var(--space-sm);
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  color: var(--color-text-muted);
}


/* ---------- About / Bio ---------- */
.about-header {
  display: flex;
  flex-direction: column;
  gap: var(--space-2xl);
  margin-bottom: var(--space-3xl);
}

.headshot-placeholder {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: var(--color-surface-2);
  border: 2px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-accent);
  letter-spacing: 0.05em;
  flex-shrink: 0;
}

.bio-text p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
  max-width: 640px;
}

.bio-text p:first-child {
  color: var(--color-text);
  font-size: var(--text-lg);
}

.philosophy {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: var(--space-2xl);
  margin-top: var(--space-3xl);
}

.philosophy h2 {
  font-size: var(--text-xl);
  margin-bottom: var(--space-lg);
}

.philosophy p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
  max-width: 640px;
}

.philosophy p:last-child {
  margin-bottom: 0;
}


/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  gap: var(--space-3xl);
}

.social-buttons {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.contact-form {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  padding: var(--space-2xl);
}

.contact-form h2 {
  font-size: var(--text-xl);
  margin-bottom: var(--space-lg);
}

.form-group {
  margin-bottom: var(--space-lg);
}

.form-group label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xs);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  font-family: var(--font-stack);
  font-size: var(--text-base);
  color: var(--color-text);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  transition: border-color var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-accent);
}

.form-group textarea {
  resize: vertical;
  min-height: 150px;
}

.form-status {
  font-size: var(--text-sm);
  margin-top: var(--space-md);
  display: none;
}

.form-status.is-success {
  display: block;
  color: #22c55e;
}

.form-status.is-error {
  display: block;
  color: #ef4444;
}


/* ---------- 404 ---------- */
.error-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--space-2xl);
}

.error-code {
  font-size: clamp(5rem, 10vw, 10rem);
  font-weight: 800;
  letter-spacing: -0.05em;
  color: var(--color-surface-2);
  line-height: 1;
  margin-bottom: var(--space-md);
}

.error-page h1 {
  font-size: var(--text-xl);
  margin-bottom: var(--space-md);
}

.error-page p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-2xl);
}


/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-3xl) 0;
}

.footer-inner {
  display: grid;
  gap: var(--space-2xl);
}

.footer-brand {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: var(--space-sm);
}

.footer-tagline {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.footer-heading {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-md);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer-links a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.footer-links a:hover {
  color: var(--color-accent-light);
}

.footer-bottom {
  border-top: 1px solid var(--color-border);
  margin-top: var(--space-2xl);
  padding-top: var(--space-xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}


/* ---------- Page Header (inner pages) ---------- */
.page-header {
  padding: calc(var(--nav-height) + var(--space-4xl)) 0 var(--space-3xl);
}

.page-header h1 {
  font-size: var(--text-2xl);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-md);
}

.page-header p {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 600px;
}


/* ==========================================================================
   Responsive — Tablet (768px)
   ========================================================================== */
@media (min-width: 768px) {
  .nav-links {
    display: flex;
  }

  .nav-toggle {
    display: none;
  }

  .capabilities-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .about-header {
    flex-direction: row;
    align-items: flex-start;
  }

  .contact-grid {
    grid-template-columns: 1fr 1fr;
  }

  .footer-inner {
    grid-template-columns: 2fr 1fr 1fr;
  }

  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
  }

  .social-buttons {
    flex-direction: row;
    flex-wrap: wrap;
  }
}


/* ==========================================================================
   Responsive — Desktop (1024px)
   ========================================================================== */
@media (min-width: 1024px) {
  .hero {
    padding-top: calc(var(--nav-height) + var(--space-5xl) + var(--space-2xl));
    padding-bottom: calc(var(--space-5xl) + var(--space-2xl));
  }

  .case-study {
    padding: var(--space-3xl);
  }

  .capability-card {
    padding: var(--space-3xl);
  }
}


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