/* ===== DESIGN TOKENS ===== */
:root {
  /* Type Scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);

  /* Spacing (4px base) */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;
  --content-full: 100%;

  /* Fonts */
  --font-display: 'DM Serif Display', Georgia, serif;
  --font-body: 'DM Sans', 'Helvetica Neue', sans-serif;
}

/* ===== LIGHT MODE (default) ===== */
:root,
[data-theme='light'] {
  --color-bg: #f5f7fa;
  --color-surface: #ffffff;
  --color-surface-2: #f0f3f7;
  --color-surface-offset: #e8ecf1;
  --color-divider: #d1d9e4;
  --color-border: #c3cddb;
  --color-text: #1a2332;
  --color-text-muted: #5a6b80;
  --color-text-faint: #94a3b8;
  --color-text-inverse: #f5f7fa;
  --color-primary: #1b4f72;
  --color-primary-hover: #153d59;
  --color-primary-active: #0f2d42;
  --color-primary-highlight: #dae8f3;
  --color-accent: #2e86ab;
  --color-accent-hover: #247092;

  --shadow-sm: 0 1px 2px oklch(0.25 0.02 230 / 0.06);
  --shadow-md: 0 4px 12px oklch(0.25 0.02 230 / 0.08);
  --shadow-lg: 0 12px 32px oklch(0.25 0.02 230 / 0.12);
}

/* ===== DARK MODE ===== */
[data-theme='dark'] {
  --color-bg: #0f1722;
  --color-surface: #162031;
  --color-surface-2: #1c2940;
  --color-surface-offset: #141d2d;
  --color-divider: #243249;
  --color-border: #2d3e58;
  --color-text: #d4dde8;
  --color-text-muted: #8899ad;
  --color-text-faint: #506075;
  --color-text-inverse: #0f1722;
  --color-primary: #5a9fc4;
  --color-primary-hover: #3d87b3;
  --color-primary-active: #2b6f99;
  --color-primary-highlight: #1e3350;
  --color-accent: #5ab8d4;
  --color-accent-hover: #42a3c1;

  --shadow-sm: 0 1px 2px oklch(0 0 0 / 0.25);
  --shadow-md: 0 4px 12px oklch(0 0 0 / 0.35);
  --shadow-lg: 0 12px 32px oklch(0 0 0 / 0.45);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg: #0f1722;
    --color-surface: #162031;
    --color-surface-2: #1c2940;
    --color-surface-offset: #141d2d;
    --color-divider: #243249;
    --color-border: #2d3e58;
    --color-text: #d4dde8;
    --color-text-muted: #8899ad;
    --color-text-faint: #506075;
    --color-text-inverse: #0f1722;
    --color-primary: #5a9fc4;
    --color-primary-hover: #3d87b3;
    --color-primary-active: #2b6f99;
    --color-primary-highlight: #1e3350;
    --color-accent: #5ab8d4;
    --color-accent-hover: #42a3c1;
    --shadow-sm: 0 1px 2px oklch(0 0 0 / 0.25);
    --shadow-md: 0 4px 12px oklch(0 0 0 / 0.35);
    --shadow-lg: 0 12px 32px oklch(0 0 0 / 0.45);
  }
}

/* ===== GLOBAL ===== */
a {
  color: var(--color-primary);
  text-decoration: none;
}
a:hover {
  color: var(--color-primary-hover);
}

/* ===== SKIP LINK ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  z-index: 100;
}
.skip-link:focus {
  top: var(--space-2);
}

/* ===== HEADER ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: oklch(from var(--color-bg) l c h / 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid oklch(from var(--color-text) l c h / 0.08);
  transition: box-shadow 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}
.site-header.scrolled {
  box-shadow: var(--shadow-sm);
}
.header-inner {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding: var(--space-3) var(--space-4);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}
.logo-mark {
  flex-shrink: 0;
}
.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}
.logo-brand {
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 1rem + 1vw, 1.5rem);
  font-weight: 400;
  letter-spacing: 0.03em;
  color: var(--color-primary);
}
.logo-sub {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 500;
}

/* Nav */
.nav-desktop {
  display: none;
  align-items: center;
  gap: var(--space-6);
}
.nav-desktop a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  font-weight: 500;
  letter-spacing: 0.01em;
  text-decoration: none;
  position: relative;
  padding-block: var(--space-1);
}
.nav-desktop a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}
.nav-desktop a:hover {
  color: var(--color-text);
}
.nav-desktop a:hover::after {
  width: 100%;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* Theme toggle */
.theme-toggle {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
}
.theme-toggle:hover {
  background: var(--color-surface-offset);
  color: var(--color-text);
}

/* Mobile menu button */
.menu-btn {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
}
.menu-btn:hover {
  background: var(--color-surface-offset);
  color: var(--color-text);
}

/* Mobile nav */
.nav-mobile {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-divider);
  box-shadow: var(--shadow-lg);
  padding: var(--space-4);
}
.nav-mobile.open {
  display: block;
}
.nav-mobile a {
  display: block;
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-base);
  color: var(--color-text);
  font-weight: 500;
  border-radius: var(--radius-md);
  text-decoration: none;
}
.nav-mobile a:hover,
.nav-mobile a:active {
  background: var(--color-surface-2);
  color: var(--color-primary);
}

@media (min-width: 768px) {
  .nav-desktop {
    display: flex;
  }
  .menu-btn {
    display: none;
  }
}

/* ===== HERO ===== */
.hero {
  position: relative;
  min-height: 70vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to right,
    oklch(from var(--color-bg) l c h / 0.95) 0%,
    oklch(from var(--color-bg) l c h / 0.7) 50%,
    oklch(from var(--color-bg) l c h / 0.3) 100%
  );
}
.hero-content {
  position: relative;
  z-index: 1;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding: var(--space-16) var(--space-4);
  display: grid;
  gap: var(--space-6);
  max-width: 640px;
  margin-left: clamp(var(--space-4), 5vw, 8rem);
}
.hero h1 {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 400;
  color: var(--color-text);
  letter-spacing: -0.01em;
}
.hero h1 span {
  color: var(--color-primary);
}
.hero-tagline {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  max-width: 48ch;
  line-height: 1.7;
}
.hero-cta {
  display: flex;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-top: var(--space-2);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-sm);
  font-weight: 600;
  border-radius: var(--radius-md);
  text-decoration: none;
  line-height: 1.4;
  min-height: 44px;
}
.btn-primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}
.btn-primary:hover {
  background: var(--color-primary-hover);
  color: var(--color-text-inverse);
}
.btn-primary:active {
  background: var(--color-primary-active);
}
.btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid oklch(from var(--color-primary) l c h / 0.35);
}
.btn-secondary:hover {
  background: var(--color-primary-highlight);
  color: var(--color-primary-hover);
}

/* ===== SECTIONS ===== */
.section {
  padding: clamp(var(--space-12), 6vw, var(--space-24)) var(--space-4);
}
.section-alt {
  background: var(--color-surface);
}
.container {
  max-width: var(--content-wide);
  margin-inline: auto;
}
.section-header {
  margin-bottom: clamp(var(--space-8), 4vw, var(--space-12));
}
.section-label {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-primary);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: var(--space-3);
}
.section-title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 400;
  color: var(--color-text);
}
.section-desc {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  max-width: 56ch;
  margin-top: var(--space-3);
}

/* ===== ABOUT SECTION ===== */
.about-grid {
  display: grid;
  gap: var(--space-8);
  align-items: center;
}
.about-image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}
.about-image img {
  width: 100%;
  height: auto;
  display: block;
}
.about-text p {
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
  line-height: 1.7;
}
.about-text p:last-child {
  margin-bottom: 0;
}

@media (min-width: 768px) {
  .about-grid {
    grid-template-columns: 1fr 1.2fr;
    gap: var(--space-12);
  }
}

/* ===== SERVICES ===== */
.services-grid {
  display: grid;
  gap: var(--space-6);
}
.service-card {
  background: var(--color-surface);
  padding: var(--space-6) var(--space-5);
  border-radius: var(--radius-lg);
  border: 1px solid oklch(from var(--color-text) l c h / 0.06);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-interactive), transform var(--transition-interactive);
}
.service-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.service-card h3 {
  font-family: var(--font-body);
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}
.service-card p {
  color: var(--color-text-muted);
  font-size: var(--text-base);
  line-height: 1.7;
}
.service-icon {
  width: 32px;
  height: 32px;
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}

@media (min-width: 640px) {
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}
@media (min-width: 1024px) {
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .services-grid .service-card:last-child {
    grid-column: 1 / -1;
    max-width: 50%;
    margin-inline: auto;
  }
}

/* ===== CLIENTS SECTION ===== */
.clients-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(200px, 100%), 1fr));
  gap: var(--space-4);
}
.client-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--color-surface);
  border-radius: var(--radius-md);
  border: 1px solid oklch(from var(--color-text) l c h / 0.06);
}
.client-dot {
  width: 8px;
  height: 8px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  flex-shrink: 0;
}
.client-item span {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text);
}

/* ===== APPROACH SECTION ===== */
.approach-steps {
  display: grid;
  gap: var(--space-6);
  counter-reset: step;
}
.step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-5);
  align-items: start;
}
.step-num {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  color: var(--color-text-inverse);
  font-size: var(--text-sm);
  font-weight: 700;
  flex-shrink: 0;
}
.step-body h3 {
  font-family: var(--font-body);
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}
.step-body p {
  color: var(--color-text-muted);
  line-height: 1.7;
}

@media (min-width: 768px) {
  .approach-steps {
    grid-template-columns: 1fr 1fr;
  }
}

/* ===== CONTACT ===== */
.contact-grid {
  display: grid;
  gap: var(--space-8);
}
.contact-info {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}
.contact-method {
  display: flex;
  gap: var(--space-4);
  align-items: start;
}
.contact-icon {
  width: 24px;
  height: 24px;
  color: var(--color-primary);
  flex-shrink: 0;
  margin-top: 2px;
}
.contact-method h3 {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: var(--space-1);
}
.contact-method p,
.contact-method a {
  font-size: var(--text-base);
  color: var(--color-text-muted);
}
.contact-method a:hover {
  color: var(--color-primary);
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}
.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}
.form-group label {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text);
}
.form-group input,
.form-group textarea {
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  font-size: var(--text-base);
  color: var(--color-text);
  line-height: 1.5;
}
.form-group input:focus,
.form-group textarea:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 1px;
  border-color: transparent;
}
.form-group textarea {
  min-height: 120px;
  resize: vertical;
}

@media (min-width: 768px) {
  .contact-grid {
    grid-template-columns: 1fr 1.3fr;
    gap: var(--space-12);
  }
}

/* ===== FOOTER ===== */
.site-footer {
  padding: var(--space-8) var(--space-4);
  background: var(--color-surface);
  border-top: 1px solid oklch(from var(--color-text) l c h / 0.06);
}
.footer-inner {
  max-width: var(--content-wide);
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  align-items: center;
  text-align: center;
}
.footer-legal {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
}
.footer-legal a {
  color: var(--color-text-muted);
}
.footer-legal a:hover {
  color: var(--color-primary);
}
.footer-name {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  line-height: 1.6;
}

@media (min-width: 768px) {
  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}

/* ===== ANIMATIONS ===== */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}