/* Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body { min-height: 100vh; }

/* Header scroll state */
#site-header { transition: background 0.4s ease, box-shadow 0.4s ease, padding 0.3s ease; }
#site-header.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(16px);
    box-shadow: 0 1px 0 rgba(16, 42, 67, 0.06), 0 4px 24px rgba(16, 42, 67, 0.06);
}

/* Navigation links */
.nav-link { position: relative; }
.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: #f59e0b;
    transition: width 0.3s ease;
    border-radius: 1px;
}
.nav-link:hover::after { width: 100%; }

/* Mobile menu button */
#menu-btn { z-index: 60; }
.hamburger-line { transition: transform 0.3s ease, opacity 0.3s ease; }
#menu-btn[aria-expanded="true"] .hamburger-line:nth-child(1) { transform: translateY(7px) rotate(45deg); }
#menu-btn[aria-expanded="true"] .hamburger-line:nth-child(2) { opacity: 0; }
#menu-btn[aria-expanded="true"] .hamburger-line:nth-child(3) { transform: translateY(-7px) rotate(-45deg); width: 1.25rem; }

/* Mobile menu */
#mobile-menu.open { opacity: 1 !important; pointer-events: all !important; }
.mobile-nav-link { transition: color 0.3s ease; }

/* Scroll reveal */
.reveal {
    opacity: 1;
    transform: translateY(0);
    transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1), transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}
@media (prefers-reduced-motion: no-preference) {
    .reveal {
        opacity: 0;
        transform: translateY(24px);
    }
    .reveal.revealed {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Selection */
::selection { background: rgba(245, 158, 11, 0.2); color: #102a43; }

/* Scrollbar */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: #f0f4f8; }
::-webkit-scrollbar-thumb { background: #bcccdc; border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #9fb3c8; }