/* ========== Base ========== */
body {
  font-family: var(--font-body);
  background-color: var(--color-bg);
  color: var(--color-text);
  transition: background-color var(--transition-base), color var(--transition-base);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  line-height: 1.2;
  font-weight: 700;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }

p { color: var(--color-text-muted); }

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

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

.section {
  padding: var(--space-4xl) 0;
}

.section-title {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

/* ========== Gradient Text ========== */
.gradient-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ========== Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-xl);
  border-radius: var(--radius-full);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1rem;
  transition: all var(--transition-base);
  text-decoration: none;
}

.btn-primary {
  background: var(--gradient-primary);
  color: #fff;
  box-shadow: var(--glow-primary);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--glow-primary), 0 8px 25px rgba(0, 0, 0, 0.3);
  color: #fff;
}

.btn-outline {
  border: 2px solid var(--color-primary);
  color: var(--color-primary);
  background: transparent;
}

.btn-outline:hover {
  background: var(--color-primary);
  color: #fff;
  transform: translateY(-2px);
}

/* ========== Cards ========== */
.card {
  background: var(--card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  transition: all var(--transition-base);
}

.card:hover {
  border-color: var(--card-hover-border);
  box-shadow: var(--glow-primary);
  transform: translateY(-4px);
}

/* ========== Navigation ========== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--nav-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: background-color var(--transition-base);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.nav-logo {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.nav-logo:hover {
  color: var(--color-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.nav-links a {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: width var(--transition-base);
}

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

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

/* Theme Switcher */
.theme-switcher {
  display: flex;
  gap: 6px;
  align-items: center;
  margin-left: var(--space-md);
}

.theme-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-dot:hover {
  transform: scale(1.3);
}

.theme-dot[data-theme="neon"] {
  background: #7C3AED;
}

.theme-dot[data-theme="bright"] {
  background: linear-gradient(135deg, #F43F5E, #6D28D9);
}

.theme-dot[data-theme="retro"] {
  background: #BFFF00;
}

.theme-dot.active {
  border-color: var(--color-text);
  box-shadow: 0 0 8px currentColor;
}

/* Hamburger */
.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-sm);
  cursor: pointer;
}

.nav-hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: all var(--transition-fast);
}

.nav-hamburger.open span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-hamburger.open span:nth-child(2) {
  opacity: 0;
}

.nav-hamburger.open span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* Mobile Nav */
@media (max-width: 768px) {
  .nav-hamburger {
    display: flex;
  }

  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--color-bg);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--space-xl);
    transform: translateX(100%);
    transition: transform var(--transition-base);
  }

  .nav-menu.open {
    transform: translateX(0);
  }

  .nav-links {
    flex-direction: column;
    gap: var(--space-xl);
  }

  .nav-links a {
    font-size: 1.5rem;
  }

  .theme-switcher {
    margin-left: 0;
    margin-top: var(--space-lg);
  }
}

/* ========== Footer ========== */
.footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-2xl) 0;
  text-align: center;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
}

.footer-tagline {
  font-family: var(--font-accent);
  font-size: 1.25rem;
  color: var(--color-primary);
}

.footer-links {
  display: flex;
  gap: var(--space-lg);
}

.footer-links a {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  transition: color var(--transition-fast);
}

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

.footer-copy {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

/* ========== Content offset for fixed nav ========== */
main {
  padding-top: var(--nav-height);
}

/* ========== Animated Background ========== */
.hero-gradient-bg {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 20% 50%, rgba(124, 58, 237, 0.15) 0%, transparent 50%),
              radial-gradient(ellipse at 80% 50%, rgba(236, 72, 153, 0.15) 0%, transparent 50%),
              radial-gradient(ellipse at 50% 80%, rgba(16, 185, 129, 0.1) 0%, transparent 50%);
  animation: heroGradient 8s ease-in-out infinite alternate;
  pointer-events: none;
  z-index: 0;
}

@keyframes heroGradient {
  0% { opacity: 0.6; transform: scale(1); }
  100% { opacity: 1; transform: scale(1.05); }
}

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

.text-center { text-align: center; }
.text-muted { color: var(--color-text-muted); }
.font-accent { font-family: var(--font-accent); }

/* ========== Badge ========== */
.badge {
  display: inline-block;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
  background: var(--color-primary);
  color: #fff;
}

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

/* ========== Tag ========== */
.tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.tag:hover, .tag.active {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: rgba(124, 58, 237, 0.1);
}