.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 15, 26, 0.4);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255,255,255,.07);
  box-shadow: 0 20px 60px rgba(0,0,0,.8);
}

.navbar-inner {
  height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: .6rem;
  font-weight: 500;
  color: var(--text-main);
  letter-spacing: -0.03em;
}

.brand-logo {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: var(--grad-accent);
  display: grid;
  place-items: center;
  font-weight: 600;
  color: #fff;
  font-size: .9rem;
  box-shadow: 0 20px 40px rgba(99,102,241,.6);
}
.brand-text {
  font-size: 1rem;
  font-weight: 600;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1rem;
  transition: var(--transition-fast);
}

.nav-links .nav-item {
  font-size: .9rem;
  color: var(--text-dim);
  position: relative;
  transition: color var(--transition-fast);
}
.nav-links .nav-item:hover {
  color: var(--text-main);
}
.nav-links .nav-item::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -4px;
  height: 2px;
  background: var(--grad-accent);
  border-radius: 999px;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-fast);
  box-shadow: 0 8px 20px rgba(99,102,241,.7);
}
.nav-links .nav-item:hover::after {
  transform: scaleX(1);
}

/* burger */
.burger {
  display: none;
  background: transparent;
  border: 0;
  cursor: pointer;
  padding: .5rem;
  position: relative;
  z-index: 101;
}
.burger span {
  display: block;
  width: 26px;
  height: 2px;
  background: #fff;
  border-radius: 999px;
  transition: var(--transition-fast);
}
.burger span + span {
  margin-top: 6px;
}
.burger.active span:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}
.burger.active span:nth-child(2) {
  opacity: 0;
}
.burger.active span:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* buttons in navbar */
.btn-outline-sm {
  background: rgba(255,255,255,.03);
  border: 1px solid rgba(255,255,255,.15);
  color: var(--text-main);
  border-radius: var(--radius-md);
  padding: .6rem .9rem;
  font-size: .8rem;
  font-weight: 500;
  line-height: 1;
  transition: var(--transition-fast);
}
.btn-outline-sm:hover {
  background: rgba(255,255,255,.07);
}

.btn-main-sm {
  background: var(--grad-accent);
  border-radius: var(--radius-md);
  padding: .6rem .9rem;
  font-size: .8rem;
  font-weight: 500;
  line-height: 1;
  color: #fff;
  box-shadow: 0 16px 40px rgba(99,102,241,.5);
  transition: var(--transition-fast);
  position: relative;
  overflow: hidden;
}
.btn-main-sm:hover {
  transform: translateY(-1px) scale(1.02);
  box-shadow: 0 24px 60px rgba(99,102,241,.6);
}

/* glow animation for CTA buttons */
.btn-glow {
  box-shadow: 0 0 30px rgba(99,102,241,.8), 0 0 80px rgba(99,102,241,.5);
  animation: pulseGlow 2.5s infinite;
}
@keyframes pulseGlow {
  0%,100% { box-shadow: 0 0 30px rgba(99,102,241,.7), 0 0 80px rgba(99,102,241,.4); }
  50%     { box-shadow: 0 0 40px rgba(99,102,241,1), 0 0 110px rgba(99,102,241,.7); }
}

/* responsive menu */
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 70px;
    right: 1rem;
    background: rgba(10,15,26,.9);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255,255,255,.1);
    box-shadow: 0 30px 120px rgba(0,0,0,.9),0 60px 180px rgba(99,102,241,.5);
    border-radius: var(--radius-lg);
    padding: 1rem;
    min-width: 200px;
    flex-direction: column;
    gap: .9rem;
    opacity: 0;
    pointer-events: none;
    transform: translateY(-10px) scale(.98);
    transition: var(--transition-fast);
    z-index: 1000;
  }
  .nav-links.open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0) scale(1);
  }

  .btn-outline-sm,
  .btn-main-sm {
    width: 100%;
    text-align: center;
  }

  .burger {
    display: block;
  }
}