/* ============================================
   Yield Digital Creative — Design System
   ============================================ */

:root {
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Light theme */
  --bg: #fafafa;
  --bg-elevated: #ffffff;
  --bg-subtle: #f4f4f5;
  --text: #18181b;
  --text-secondary: #52525b;
  --text-muted: #a1a1aa;
  --border: #e4e4e7;
  --border-subtle: #f4f4f5;

  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --accent-subtle: rgba(99, 102, 241, 0.08);
  --accent-glow: rgba(99, 102, 241, 0.25);

  --gradient-start: #6366f1;
  --gradient-end: #8b5cf6;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.08);

  --header-bg: rgba(250, 250, 250, 0.8);
  --radius: 12px;
  --radius-lg: 20px;
  --transition: 0.2s ease;
}

[data-theme="dark"] {
  --bg: #09090b;
  --bg-elevated: #18181b;
  --bg-subtle: #27272a;
  --text: #fafafa;
  --text-secondary: #a1a1aa;
  --text-muted: #71717a;
  --border: #27272a;
  --border-subtle: #1f1f23;

  --accent: #818cf8;
  --accent-hover: #6366f1;
  --accent-subtle: rgba(129, 140, 248, 0.1);
  --accent-glow: rgba(129, 140, 248, 0.2);

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.4);

  --header-bg: rgba(9, 9, 11, 0.85);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background var(--transition), color var(--transition);
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

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

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition), border-color var(--transition);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  font-weight: 600;
  font-size: 0.9375rem;
}

.logo-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: #fff;
  border-radius: 8px;
  font-weight: 700;
  font-size: 0.875rem;
}

.logo-text {
  display: none;
}

@media (min-width: 640px) {
  .logo-text {
    display: inline;
  }
}

.nav-links {
  display: none;
  gap: 2rem;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--text);
}

@media (min-width: 768px) {
  .nav-links {
    display: flex;
  }
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.theme-toggle {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-elevated);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

.theme-toggle:hover {
  color: var(--text);
  border-color: var(--text-muted);
}

.icon-sun,
.icon-moon {
  position: absolute;
  transition: opacity var(--transition), transform var(--transition);
}

[data-theme="light"] .icon-sun {
  opacity: 1;
  transform: rotate(0deg);
}

[data-theme="light"] .icon-moon {
  opacity: 0;
  transform: rotate(-90deg);
}

[data-theme="dark"] .icon-sun {
  opacity: 0;
  transform: rotate(90deg);
}

[data-theme="dark"] .icon-moon {
  opacity: 1;
  transform: rotate(0deg);
}

.menu-toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.5rem;
  height: 2.5rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg-elevated);
  cursor: pointer;
  padding: 0.5rem;
}

.menu-toggle span {
  display: block;
  height: 2px;
  background: var(--text);
  border-radius: 1px;
  transition: all var(--transition);
}

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

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

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

@media (min-width: 768px) {
  .menu-toggle {
    display: none;
  }
}

.mobile-menu {
  display: none;
  flex-direction: column;
  padding: 1rem 1.5rem 1.5rem;
  border-top: 1px solid var(--border);
  background: var(--header-bg);
}

.mobile-menu.open {
  display: flex;
}

.mobile-menu a {
  padding: 0.75rem 0;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-subtle);
}

.mobile-menu a:last-child {
  border-bottom: none;
}

@media (min-width: 768px) {
  .mobile-menu {
    display: none !important;
  }
}

/* Hero */
.hero {
  position: relative;
  padding: 8rem 0 5rem;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% -20%, var(--accent-glow), transparent),
    radial-gradient(ellipse 50% 40% at 80% 50%, rgba(139, 92, 246, 0.08), transparent);
  pointer-events: none;
}

.hero-content {
  position: relative;
  text-align: center;
  max-width: 720px;
}

.hero-badge {
  display: inline-block;
  padding: 0.375rem 1rem;
  background: var(--accent-subtle);
  color: var(--accent);
  font-size: 0.8125rem;
  font-weight: 600;
  border-radius: 100px;
  margin-bottom: 1.5rem;
  letter-spacing: 0.02em;
}

.hero h1 {
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 1.25rem;
}

.gradient-text {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.125rem);
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto 2rem;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-bottom: 3.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: 10px;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-primary {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  color: #fff;
  box-shadow: 0 2px 12px var(--accent-glow);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 20px var(--accent-glow);
}

.btn-secondary {
  background: var(--bg-elevated);
  color: var(--text);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--text-muted);
  background: var(--bg-subtle);
}

.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  padding: 1.5rem 2rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  max-width: 480px;
  margin: 0 auto;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.125rem;
}

.stat-value {
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--text);
}

.stat-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 500;
}

.stat-divider {
  width: 1px;
  height: 2rem;
  background: var(--border);
}

/* Sections */
.section-header {
  text-align: center;
  max-width: 560px;
  margin: 0 auto 3rem;
}

.section-tag {
  display: inline-block;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.75rem;
}

.section-header h2,
.about-content h2,
.contact-info h2 {
  font-size: clamp(1.75rem, 3.5vw, 2.25rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-bottom: 0.75rem;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* Services */
.services {
  padding: 5rem 0;
}

.services-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

@media (min-width: 640px) {
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.service-card {
  padding: 2rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: all var(--transition);
}

.service-card:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.service-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  background: var(--accent-subtle);
  color: var(--accent);
  border-radius: 10px;
  margin-bottom: 1.25rem;
}

.service-card h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.service-card p {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

.btn-card {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.5rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--accent);
  background: var(--accent-subtle);
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
  text-align: center;
}

.btn-card:hover {
  background: var(--accent);
  color: #fff;
}

/* About */
.about {
  padding: 5rem 0;
  background: var(--bg-subtle);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  align-items: center;
}

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

.about-content p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  font-size: 0.9375rem;
  line-height: 1.7;
}

.about-list {
  margin-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.about-list li {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.9375rem;
  font-weight: 500;
}

.about-list svg {
  color: var(--accent);
  flex-shrink: 0;
}

.visual-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.visual-header {
  display: flex;
  gap: 0.5rem;
  padding: 0.875rem 1rem;
  background: var(--bg-subtle);
  border-bottom: 1px solid var(--border);
}

.dot {
  width: 0.75rem;
  height: 0.75rem;
  border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #eab308; }
.dot.green { background: #22c55e; }

.visual-body {
  padding: 1.5rem;
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  font-size: 0.875rem;
  line-height: 1.8;
}

.code-line {
  white-space: nowrap;
}

.indent { padding-left: 1.5rem; }
.indent-2 { padding-left: 3rem; }

.code-keyword { color: #c084fc; }
.code-class { color: #60a5fa; }
.code-fn { color: #34d399; }
.code-comment { color: var(--text-muted); }
.code-var { color: #f472b6; }
.code-string { color: #fbbf24; }

/* Contact */
.contact {
  padding: 5rem 0;
}

.contact-card {
  background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
  border-radius: var(--radius-lg);
  padding: 3rem 2rem;
  color: #fff;
  text-align: center;
}

@media (min-width: 640px) {
  .contact-card {
    padding: 4rem 3rem;
  }
}

.contact-info {
  max-width: 520px;
  margin: 0 auto;
}

.contact-info .section-tag {
  color: rgba(255, 255, 255, 0.8);
}

.contact-info h2 {
  color: #fff;
}

.contact-info > p {
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 2rem;
  font-size: 1rem;
  line-height: 1.7;
}

.contact-details {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  align-items: center;
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  padding: 0.75rem 1.25rem;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 10px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: #fff;
  transition: all var(--transition);
}

.contact-link:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: translateY(-1px);
}

/* Footer */
.footer {
  padding: 2rem 0;
  border-top: 1px solid var(--border);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  text-align: center;
}

@media (min-width: 640px) {
  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
  }
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  font-weight: 600;
  font-size: 0.875rem;
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--text-muted);
}