/* Professional navigation, shared across all pages */

:root {
  --nav-h: var(--header-h, 52px);
  --nav-max: 1200px;
  --nav-pad: 20px;
  --nav-border: #e4e4e7;
  --nav-surface: rgba(255, 255, 255, 0.82);
  --nav-text: #09090b;
  --nav-muted: #71717a;
  --nav-subtle: #f4f4f5;
  --nav-accent: #2563eb;
  --nav-font:
    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --nav-radius: 8px;
  --nav-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 4px 24px rgba(0, 0, 0, 0.04);
}

/* Shell */
.header {
  position: fixed !important;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1100 !important;
  background: var(--nav-surface) !important;
  border-bottom: 1px solid var(--nav-border) !important;
  backdrop-filter: blur(16px) saturate(180%) !important;
  -webkit-backdrop-filter: blur(16px) saturate(180%) !important;
  box-shadow: none !important;
  transition:
    box-shadow 0.2s ease,
    border-color 0.2s ease;
}

.header.scrolled {
  background: rgba(255, 255, 255, 0.94) !important;
  border-bottom-color: #e4e4e7 !important;
  box-shadow: var(--nav-shadow) !important;
}

.header-inner {
  max-width: var(--nav-max) !important;
  margin: 0 auto;
  padding: 0 var(--nav-pad) !important;
  height: var(--nav-h) !important;
  min-height: var(--nav-h) !important;
  display: flex !important;
  align-items: center !important;
  justify-content: space-between !important;
  gap: 16px !important;
  flex-wrap: nowrap !important;
}

/* Logo */
.logo {
  display: inline-flex;
  align-items: center;
  font-family: var(--nav-font) !important;
  font-size: 15px !important;
  font-weight: 600 !important;
  letter-spacing: -0.035em !important;
  line-height: 1 !important;
  color: var(--nav-text) !important;
  text-decoration: none !important;
  flex-shrink: 0;
  padding: 6px 0;
}

.logo-free {
  color: var(--nav-text) !important;
}

.logo-university {
  color: #3f3f46 !important;
}

.logo-tools {
  color: #a1a1aa !important;
  font-weight: 500 !important;
}

/* Nav links */
.nav {
  display: flex !important;
  align-items: center !important;
  gap: 2px !important;
  flex-shrink: 0;
}

.nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  font-family: var(--nav-font) !important;
  font-size: 13px !important;
  font-weight: 500 !important;
  letter-spacing: -0.01em !important;
  text-transform: none !important;
  color: var(--nav-muted) !important;
  text-decoration: none !important;
  padding: 7px 11px !important;
  border-radius: var(--nav-radius) !important;
  white-space: nowrap;
  transition:
    color 0.15s ease,
    background 0.15s ease;
}

.nav-link::after {
  display: none !important;
}

.nav-link:hover {
  color: var(--nav-text) !important;
  background: var(--nav-subtle) !important;
}

.nav-link.active {
  color: var(--nav-text) !important;
  background: var(--nav-subtle) !important;
}

/* Donate */
.btn-donate {
  display: inline-flex !important;
  align-items: center;
  justify-content: center;
  margin-left: 6px !important;
  padding: 7px 14px !important;
  font-family: var(--nav-font) !important;
  font-size: 13px !important;
  font-weight: 500 !important;
  letter-spacing: -0.01em !important;
  text-transform: none !important;
  color: #fff !important;
  background: var(--nav-text) !important;
  border: 1px solid var(--nav-text) !important;
  border-radius: var(--nav-radius) !important;
  text-decoration: none !important;
  white-space: nowrap;
  box-shadow: none !important;
  transition:
    background 0.15s ease,
    border-color 0.15s ease,
    transform 0.15s ease;
}

.btn-donate:hover {
  background: #27272a !important;
  border-color: #27272a !important;
  transform: none !important;
}

/* Dropdown */
.nav-dropdown {
  position: relative;
  display: inline-flex;
  align-items: center;
}

.nav-dropdown-btn {
  font-family: var(--nav-font) !important;
  font-size: 13px !important;
  font-weight: 500 !important;
  color: var(--nav-muted) !important;
  background: transparent !important;
  border: none !important;
  border-radius: var(--nav-radius) !important;
  padding: 7px 11px !important;
  cursor: pointer;
  transition:
    color 0.15s ease,
    background 0.15s ease;
}

.nav-dropdown-btn:hover {
  color: var(--nav-text) !important;
  background: var(--nav-subtle) !important;
}

.desktop-dropdown-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  padding: 0 !important;
  font-size: 16px !important;
  line-height: 1;
  color: var(--nav-muted) !important;
  background: transparent !important;
  border: 1px solid var(--nav-border) !important;
  border-radius: var(--nav-radius) !important;
  cursor: pointer;
  transition:
    background 0.15s ease,
    color 0.15s ease,
    border-color 0.15s ease;
}

.desktop-dropdown-toggle:hover {
  color: var(--nav-text) !important;
  background: var(--nav-subtle) !important;
  border-color: #d4d4d8 !important;
}

@media (min-width: 769px) {
  .nav-dropdown-btn {
    display: none !important;
  }

  .desktop-dropdown-toggle {
    display: inline-flex !important;
  }

  .nav-dropdown-content {
    display: none;
    position: absolute;
    top: calc(100% + 6px);
    right: 0;
    min-width: 168px;
    padding: 4px !important;
    background: #fff !important;
    border: 1px solid var(--nav-border) !important;
    border-radius: 10px !important;
    box-shadow: var(--nav-shadow) !important;
    z-index: 1200;
  }

  .nav-dropdown.is-open .nav-dropdown-content {
    display: block !important;
  }

  .nav-dropdown-content .nav-link {
    display: block !important;
    width: 100%;
    padding: 8px 10px !important;
    border-radius: 6px !important;
    font-size: 13px !important;
    border-bottom: none !important;
  }

  .nav-dropdown-content .nav-link:hover {
    background: var(--nav-subtle) !important;
  }
}

/* Mobile toggle */
.mobile-menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  padding: 0;
  font-size: 18px;
  line-height: 1;
  color: var(--nav-text);
  background: transparent;
  border: 1px solid var(--nav-border);
  border-radius: var(--nav-radius);
  cursor: pointer;
  transition: background 0.15s ease;
}

.mobile-menu-toggle:hover {
  background: var(--nav-subtle);
}

/* Tools header: search in nav */
.header--tools .header-inner {
  gap: 12px !important;
}

.header-toolbar {
  flex: 1;
  display: flex;
  align-items: center;
  gap: 8px;
  min-width: 0;
  max-width: 440px;
  margin: 0 auto;
}

.header-search-wrap {
  flex: 1;
  min-width: 0;
  position: relative;
}

.header-search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 14px;
  height: 14px;
  color: #a1a1aa;
  pointer-events: none;
}

.header--tools .tools-search {
  width: 100%;
  height: 34px;
  padding: 0 12px 0 34px;
  font-family: var(--nav-font);
  font-size: 13px;
  color: var(--nav-text);
  background: #fafafa;
  border: 1px solid var(--nav-border);
  border-radius: var(--nav-radius);
  outline: none;
  transition:
    border-color 0.15s ease,
    box-shadow 0.15s ease,
    background 0.15s ease;
}

.header--tools .tools-search::placeholder {
  color: #a1a1aa;
}

.header--tools .tools-search:focus {
  background: #fff;
  border-color: var(--nav-accent);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}

.header--tools .tools-toggle-3 {
  position: relative;
  flex-shrink: 0;
  height: 34px;
  min-width: 148px;
  padding: 2px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: #fafafa;
  border: 1px solid var(--nav-border);
  border-radius: var(--nav-radius);
  overflow: hidden;
}

.header--tools .tools-toggle-thumb {
  position: absolute;
  top: 2px;
  left: 2px;
  width: calc(50% - 2px);
  height: calc(100% - 4px);
  background: var(--nav-text);
  border-radius: 6px;
  transition: transform 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 0;
}

.header--tools .tools-toggle-3[data-mode="paid"] .tools-toggle-thumb {
  transform: translateX(100%);
}

.header--tools .tools-toggle-option {
  position: relative;
  z-index: 1;
  border: 0;
  background: transparent;
  font-family: var(--nav-font);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--nav-muted);
  cursor: pointer;
  transition: color 0.15s ease;
}

.header--tools .tools-toggle-option.active {
  color: #fff;
}

.header--tools .nav-pricing-toggle {
  flex-shrink: 0;
}

@media (min-width: 769px) {
  .header--tools .nav {
    gap: 6px !important;
  }

  .header--tools .nav-pricing-toggle {
    margin-right: 2px;
  }

  .header--tools .header-toolbar {
    max-width: 360px;
  }
}

body:has(.header--tools) main {
  padding-top: calc(var(--nav-h) + 36px) !important;
}

/* Mobile */
@media (max-width: 768px) {
  :root {
    --nav-pad: 16px;
  }

  /* Homepage/static pages: keep header one row; menu overlays instead of pushing layout */
  .header:not(.header--tools) .header-inner {
    flex-wrap: nowrap !important;
    height: var(--nav-h) !important;
    min-height: var(--nav-h) !important;
    padding-top: 0 !important;
    padding-bottom: 0 !important;
    position: relative;
  }

  .header:not(.header--tools) .nav {
    order: 3;
  }

  .header:not(.header--tools) .nav:not(.mobile-open) {
    display: none !important;
  }

  .header:not(.header--tools) .nav.mobile-open {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 1101;
    display: flex !important;
    width: auto;
    margin: 0 calc(var(--nav-pad) * -1);
    padding: 8px var(--nav-pad) 12px !important;
    background: rgba(255, 255, 255, 0.98);
    border-top: 1px solid var(--nav-border);
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.1);
    backdrop-filter: blur(16px) saturate(180%);
    -webkit-backdrop-filter: blur(16px) saturate(180%);
  }

  .header-inner {
    flex-wrap: wrap !important;
    height: auto !important;
    min-height: var(--nav-h) !important;
    padding-top: 10px !important;
    padding-bottom: 10px !important;
    gap: 10px !important;
  }

  .logo {
    order: 1;
    flex: 1;
    min-width: 0;
  }

  .mobile-menu-toggle {
    display: inline-flex;
    order: 2;
    margin-left: auto;
  }

  .header--tools .header-inner {
    flex-wrap: nowrap !important;
    height: var(--nav-h) !important;
    min-height: var(--nav-h) !important;
    padding-top: 0 !important;
    padding-bottom: 0 !important;
    gap: 10px !important;
  }

  .header--tools .logo {
    display: none !important;
  }

  .header--tools .header-toolbar {
    order: 1;
    flex: 1;
    width: auto;
    min-width: 0;
    max-width: none;
    margin: 0;
  }

  .header--tools .mobile-menu-toggle {
    order: 2;
    flex-shrink: 0;
    margin-left: 0;
  }

  .header--tools .nav-pricing-toggle {
    display: none;
    width: 100%;
    min-width: 0;
    margin-bottom: 6px;
  }

  .header--tools .nav.mobile-open .nav-pricing-toggle {
    display: grid;
  }

  .nav {
    display: none !important;
    order: 4;
    width: 100%;
    flex-direction: column !important;
    align-items: stretch !important;
    gap: 2px !important;
    padding: 8px 0 4px !important;
    border-top: 1px solid var(--nav-border);
  }

  .header--tools .nav {
    order: 3;
  }

  .header--tools .nav:not(.mobile-open) {
    display: none !important;
    width: 0;
    height: 0;
    padding: 0 !important;
    margin: 0 !important;
    border: none !important;
    overflow: hidden;
  }

  .header--tools .header-inner {
    position: relative;
  }

  .header--tools .header-inner:has(.nav.mobile-open) {
    flex-wrap: nowrap !important;
    height: var(--nav-h) !important;
    min-height: var(--nav-h) !important;
    padding-bottom: 0 !important;
  }

  .header--tools .nav.mobile-open {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 1101;
    display: flex !important;
    width: 100%;
    margin: 0 calc(var(--nav-pad) * -1);
    padding: 8px var(--nav-pad) 12px !important;
    background: rgba(255, 255, 255, 0.98);
    border-top: 1px solid var(--nav-border);
    box-shadow: 0 10px 30px rgba(15, 23, 42, 0.1);
    backdrop-filter: blur(16px) saturate(180%);
    -webkit-backdrop-filter: blur(16px) saturate(180%);
  }

  .nav.mobile-open {
    display: flex !important;
    width: 100%;
  }

  .nav.mobile-open .nav-link {
    width: 100% !important;
    justify-content: flex-start;
    padding: 12px 12px !important;
    font-size: 15px !important;
    border-radius: var(--nav-radius) !important;
    border-bottom: none !important;
    text-align: left;
  }

  /* Flat mobile menu: Home, Students, About, Terms — no "More" */
  .nav.mobile-open .nav-dropdown {
    display: contents;
  }

  .nav.mobile-open .desktop-dropdown-toggle,
  .nav.mobile-open .nav-dropdown-btn {
    display: none !important;
  }

  .nav.mobile-open .nav-dropdown-content {
    display: contents !important;
  }

  .nav.mobile-open .nav-dropdown-content .nav-link {
    padding-left: 12px !important;
    color: var(--nav-muted) !important;
  }

  .nav.mobile-open .btn-donate {
    width: 100% !important;
    margin-left: 0 !important;
    margin-top: 6px !important;
    padding: 11px 16px !important;
    text-align: center;
    justify-content: center;
  }

  .header:not(.header--tools) .nav.mobile-open,
  .header--tools .nav.mobile-open {
    max-height: min(70vh, 420px);
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    overscroll-behavior: contain;
    border-radius: 0 0 14px 14px;
    background: #ffffff !important;
    -webkit-backdrop-filter: none !important;
    backdrop-filter: none !important;
  }

  body:has(.header--tools) main {
    padding-top: calc(var(--nav-h) + 20px) !important;
    padding-left: 16px !important;
    padding-right: 16px !important;
  }

  body.page-scroll:has(.header--tools) main.scroll-main {
    padding: 0 !important;
  }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .header-toolbar {
    max-width: 280px;
  }

  .header--tools .tools-toggle-3 {
    min-width: 130px;
  }

  .nav-link {
    padding: 7px 8px !important;
    font-size: 12px !important;
  }

  .btn-donate {
    padding: 7px 11px !important;
    font-size: 12px !important;
  }
}