/* ============================================
   ENHANCED HEADER STYLING
   ============================================ */

/* ── Header Base Styling ── */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: var(--z-fixed);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  background: transparent;
}

/* ── Header Scrolled State ── */
.header.scrolled {
  background: rgba(10, 10, 15, 0.8);
  backdrop-filter: blur(20px) saturate(1.3);
  -webkit-backdrop-filter: blur(20px) saturate(1.3);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}

[data-theme="light"] .header.scrolled {
  background: rgba(250, 250, 250, 0.85);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

/* ── Header Inner ── */
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--container-xl);
  margin: 0 auto;
  padding: 0 var(--space-6);
  position: relative;
}

/* ── Header Divider Line Animation ── */
.header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.header.scrolled::after {
  opacity: 1;
}

/* ══════════════════════════════════════
   LOGO ENHANCEMENTS
   ══════════════════════════════════════ */

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  position: relative;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  padding: 8px 12px;
  border-radius: var(--radius-md);
}

.logo:hover {
  background: var(--accent-glow);
  transform: translateY(-2px);
}

.logo-mark {
  width: 44px;
  height: 44px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

/* ── Logo Ring Animations ── */
.logo-ring {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.logo-ring-outer {
  animation: logoSpin 20s linear infinite;
  transform-origin: center;
  stroke-width: 2;
}

.logo-ring-inner {
  animation: logoSpinReverse 15s linear infinite;
  transform-origin: center;
  stroke-width: 1.5;
}

.logo:hover .logo-ring-outer {
  animation-duration: 4s;
}

.logo:hover .logo-ring-inner {
  animation-duration: 3s;
}

@keyframes logoSpin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes logoSpinReverse {
  from { transform: rotate(360deg); }
  to { transform: rotate(0deg); }
}

/* ── Logo Letter Styling ── */
.logo-letter-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1px;
  z-index: 1;
  position: relative;
}

.logo-bracket {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: var(--font-bold);
  background: var(--gradient-secondary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0.6;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  line-height: 1;
}

.logo:hover .logo-bracket {
  opacity: 1;
  filter: drop-shadow(0 0 8px var(--accent-glow));
}

.logo:hover .logo-bracket-left {
  transform: translateX(-3px);
}

.logo:hover .logo-bracket-right {
  transform: translateX(3px);
}

.logo-letter {
  font-family: var(--font-sans);
  font-size: 18px;
  font-weight: var(--font-extrabold);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  transition: all 0.3s ease;
  animation: logoLetterFloat 3s ease-in-out infinite;
}

.logo:hover .logo-letter {
  filter: drop-shadow(0 0 10px var(--accent-glow));
  animation: none;
}

@keyframes logoLetterFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-2px); }
}

/* ── Logo Text ── */
.logo-text {
  display: flex;
  align-items: baseline;
  gap: 0;
  line-height: 1;
}

.logo-name {
  font-size: var(--text-xl);
  font-weight: var(--font-bold);
  color: var(--text-primary);
  letter-spacing: var(--tracking-tight);
  transition: all 0.3s ease;
}

.logo:hover .logo-name {
  color: var(--accent);
}

.logo-dot {
  font-size: var(--text-2xl);
  font-weight: var(--font-extrabold);
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  display: inline-block;
  margin: 0 -2px;
}

.logo:hover .logo-dot {
  transform: scale(1.3) rotate(15deg);
  filter: drop-shadow(0 0 8px var(--accent-glow-strong));
}

.logo-surname {
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--accent);
  letter-spacing: var(--tracking-wide);
  font-family: var(--font-mono);
  opacity: 0.8;
  transition: all 0.3s ease;
}

.logo:hover .logo-surname {
  opacity: 1;
  color: var(--accent-hover);
  letter-spacing: var(--tracking-wider);
}

/* ── Logo Mark Glow ── */
.logo-mark::after {
  content: '';
  position: absolute;
  inset: -6px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow-strong) 0%, transparent 70%);
  opacity: 0;
  transition: opacity 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  pointer-events: none;
  z-index: -1;
  filter: blur(8px);
}

.logo:hover .logo-mark::after {
  opacity: 1;
  animation: glowPulse 1.5s ease-in-out infinite;
}

@keyframes glowPulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.2); }
}

/* ══════════════════════════════════════
   NAVIGATION LINKS
   ══════════════════════════════════════ */

.nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.nav-link {
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  font-weight: var(--font-medium);
  color: var(--text-secondary);
  border-radius: var(--radius-md);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.nav-link::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: -100%;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  transition: left 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.nav-link:hover::before,
.nav-link.active::before {
  left: 0;
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent);
  background: var(--accent-glow);
  transform: translateY(-2px);
}

.nav-link.active {
  font-weight: var(--font-semibold);
  box-shadow: 0 4px 12px var(--accent-glow);
}

/* ══════════════════════════════════════
   HEADER ACTIONS
   ══════════════════════════════════════ */

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* ── Theme Toggle Button ── */
.theme-toggle {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  background: transparent;
  border: none;
  position: relative;
  overflow: hidden;
}

.theme-toggle::before {
  content: '';
  position: absolute;
  inset: -50%;
  background: var(--accent-glow);
  border-radius: 50%;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.theme-toggle:hover {
  color: var(--accent);
  background: var(--accent-glow);
  transform: scale(1.05);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
  position: relative;
  z-index: 1;
}

.theme-toggle:hover svg {
  transform: rotate(180deg) scale(1.1);
}

.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: block; }

[data-theme="light"] .theme-toggle .icon-sun { display: block; }
[data-theme="light"] .theme-toggle .icon-moon { display: none; }

/* ── Social Links in Header ── */
.social-link {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  background: transparent;
}

.social-link svg {
  width: 18px;
  height: 18px;
  transition: all 0.3s ease;
}

.social-link:hover {
  color: var(--accent);
  background: var(--accent-glow);
  transform: translateY(-3px) scale(1.1);
}

.social-link:hover svg {
  filter: drop-shadow(0 0 6px var(--accent-glow));
}

/* ══════════════════════════════════════
   MOBILE MENU BUTTON
   ══════════════════════════════════════ */

.mobile-menu-btn {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  cursor: pointer;
  background: none;
  border: none;
  position: relative;
  z-index: calc(var(--z-overlay) + 1);
  transition: all 0.3s ease;
}

.mobile-menu-btn:hover {
  color: var(--accent);
  background: var(--accent-glow);
}

.hamburger {
  width: 20px;
  height: 14px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background: currentColor;
  border-radius: var(--radius-full);
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  transform-origin: center;
}

.mobile-menu-btn.active .hamburger span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.mobile-menu-btn.active .hamburger span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.mobile-menu-btn.active .hamburger span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ══════════════════════════════════════
   MOBILE NAVIGATION
   ══════════════════════════════════════ */

.mobile-nav {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--bg-primary);
  z-index: var(--z-overlay);
  padding: calc(var(--header-height) + var(--space-8)) var(--space-6) var(--space-8);
  opacity: 0;
  transform: translateY(-20px);
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  overflow-y: auto;
  backdrop-filter: blur(20px);
}

.mobile-nav.open {
  display: flex;
  flex-direction: column;
  opacity: 1;
  transform: translateY(0);
  animation: mobileNavSlideIn 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes mobileNavSlideIn {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-bottom: var(--space-8);
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-4);
  font-size: var(--text-lg);
  font-weight: var(--font-medium);
  color: var(--text-secondary);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  overflow: hidden;
}

.mobile-nav-link::before {
  content: '';
  position: absolute;
  left: -100%;
  top: 0;
  width: 100%;
  height: 100%;
  background: var(--accent-glow);
  z-index: -1;
  transition: left 0.3s ease;
}

.mobile-nav-link:hover::before {
  left: 0;
}

.mobile-nav-link:hover {
  color: var(--accent);
  transform: translateX(8px);
}

.mobile-nav-socials {
  display: flex;
  gap: var(--space-3);
  padding-top: var(--space-6);
  border-top: 1px solid var(--border);
  justify-content: center;
  flex-wrap: wrap;
}

/* ══════════════════════════════════════
   RESPONSIVE DESIGN
   ══════════════════════════════════════ */

@media (max-width: 768px) {
  .nav {
    display: none;
  }

  .header-actions {
    gap: var(--space-2);
  }

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

  .header-inner {
    padding: 0 var(--space-4);
  }

  .logo-text {
    display: none;
  }

  .logo {
    gap: 0;
    padding: 0;
  }

  .logo:hover {
    background: transparent;
  }

  .logo-mark::after {
    display: none;
  }
}

/* ── Smooth Scrollbar Appearance ── */
.mobile-nav::-webkit-scrollbar {
  width: 6px;
}

.mobile-nav::-webkit-scrollbar-track {
  background: transparent;
}

.mobile-nav::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

.mobile-nav::-webkit-scrollbar-thumb:hover {
  background: var(--accent);
}