/**
 * ==================================================
 * Header Styles
 * Sticky with Glassmorphism - Enhanced
 * ==================================================
 */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: var(--z-sticky);
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  transform: translateY(0);
}

/* Header hidden on scroll down */
.site-header.header-hidden {
  transform: translateY(-100%);
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  background: transparent;
  backdrop-filter: blur(0px);
  -webkit-backdrop-filter: blur(0px);
  transition: all var(--transition-normal);
}

.site-header.scrolled::before {
  background: var(--color-glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-glass-border);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
}

.header-container {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* Menu Toggle Button */
.menu-toggle {
  position: relative;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: calc(var(--z-modal) + 1);
}

.hamburger {
  position: relative;
  width: 24px;
  height: 18px;
}

.hamburger-line {
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--color-text);
  border-radius: var(--radius-full);
  transition: all var(--transition-normal);
}

.hamburger-line:nth-child(1) {
  top: 0;
}
.hamburger-line:nth-child(2) {
  top: 50%;
  transform: translateY(-50%);
}
.hamburger-line:nth-child(3) {
  bottom: 0;
}

/* Hamburger Animation */
.menu-toggle.active .hamburger-line:nth-child(1) {
  top: 50%;
  transform: translateY(-50%) rotate(45deg);
  background: var(--color-primary);
}

.menu-toggle.active .hamburger-line:nth-child(2) {
  opacity: 0;
  transform: translateX(-10px);
}

.menu-toggle.active .hamburger-line:nth-child(3) {
  bottom: 50%;
  transform: translateY(50%) rotate(-45deg);
  background: var(--color-primary);
}

/* Site Logo */
.site-logo {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-1);
  text-decoration: none;
  z-index: calc(var(--z-modal) + 1);
}

.logo-svg {
  width: 100px;
  height: 35px;
}

.logo-text {
  font-family: var(--font-english);
  font-size: 28px;
  font-weight: 700;
}

.logo-subtitle {
  font-family: var(--font-english);
  font-size: var(--font-size-xs);
  color: var(--color-text-secondary);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* Theme Toggle */
.theme-toggle {
  position: relative;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-normal);
  overflow: hidden;
}

.theme-toggle:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-glow-primary);
}

.theme-icon {
  position: absolute;
  width: 20px;
  height: 20px;
  transition: all var(--transition-normal);
}

.theme-icon svg {
  width: 100%;
  height: 100%;
  color: var(--color-text);
}

/* Dark theme: show moon, hide sun */
[data-theme="dark"] .theme-icon--light {
  opacity: 0;
  transform: scale(0) rotate(-90deg);
}

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

/* Light theme: show sun, hide moon */
[data-theme="light"] .theme-icon--light {
  opacity: 1;
  transform: scale(1) rotate(0deg);
}

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