/**
 * TypingTeacher Unified Navigation System (nav.css)
 * Self-contained, accessible, responsive navigation styling for all non-kids pages.
 */

:root {
  --nav-height-desktop: 64px;
  --nav-height-mobile: 56px;
  --nav-bg: #0b0f19;
  --nav-border: #1e293b;
  --nav-text: #e2e8f0;
  --nav-text-muted: #94a3b8;
  --nav-text-hover: #ffffff;
  --nav-dropdown-bg: #0f172a;
  --nav-dropdown-border: #1e293b;
  --nav-panel-footer-bg: #0b0f19;
  --nav-item-hover: rgba(30, 41, 59, 0.7);
  --nav-focus-ring: #6366f1;
  --nav-cta-bg: #4f46e5;
  --nav-cta-hover: #4338ca;
  --nav-cta-text: #ffffff;
  --nav-dot-color: #f43f5e;
}

[data-theme="light"] {
  --nav-bg: #ffffff;
  --nav-border: #e2e8f0;
  --nav-text: #334155;
  --nav-text-muted: #64748b;
  --nav-text-hover: #0f172a;
  --nav-dropdown-bg: #ffffff;
  --nav-dropdown-border: #cbd5e1;
  --nav-panel-footer-bg: #f8fafc;
  --nav-item-hover: #f1f5f9;
  --nav-focus-ring: #4f46e5;
  --nav-cta-bg: #4f46e5;
  --nav-cta-hover: #4338ca;
  --nav-cta-text: #ffffff;
  --nav-dot-color: #e11d48;
}

/* Skip to Content Link */
.tt-skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  z-index: 10000;
  background: var(--nav-cta-bg);
  color: #ffffff;
  padding: 0.6rem 1.2rem;
  border-radius: 0.5rem;
  font-weight: 700;
  font-size: 0.875rem;
  text-decoration: none;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
  transition: top 0.15s ease;
}
.tt-skip-link:focus {
  top: 1rem;
  outline: 3px solid var(--nav-focus-ring);
  outline-offset: 2px;
}

/* Header Container */
.tt-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  width: 100%;
  height: var(--nav-height-desktop);
  background-color: var(--nav-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--nav-border);
  box-sizing: border-box;
}

@media print {
  .tt-header { display: none !important; }
}

.tt-nav-container {
  max-width: 80rem;
  margin: 0 auto;
  height: 100%;
  padding: 0 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  box-sizing: border-box;
}

@media (min-width: 640px) {
  .tt-nav-container { padding: 0 1.5rem; }
}
@media (min-width: 1024px) {
  .tt-nav-container { padding: 0 2rem; }
}

/* Brand Logo */
.tt-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
  text-decoration: none;
}
.tt-brand img {
  height: 36px;
  width: auto;
  display: block;
}
[data-theme="light"] .tt-brand .logo-dark-mode { display: none !important; }
[data-theme="light"] .tt-brand .logo-light-mode { display: block !important; }
[data-theme="dark"] .tt-brand .logo-dark-mode { display: block !important; }
[data-theme="dark"] .tt-brand .logo-light-mode { display: none !important; }

/* Desktop Navigation Menu */
.tt-nav-desktop {
  display: none;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--nav-text);
}
@media (min-width: 1024px) {
  .tt-nav-desktop { display: flex; }
}
@media (min-width: 1280px) {
  .tt-nav-desktop { gap: 0.5rem; }
}

/* Nav Item Button & Links */
.tt-nav-btn,
.tt-nav-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.5rem 0.75rem;
  border-radius: 0.75rem;
  color: var(--nav-text);
  background: transparent;
  border: 1px solid transparent;
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  line-height: 1.25;
}
.tt-nav-btn:hover,
.tt-nav-link:hover {
  color: var(--nav-text-hover);
  background-color: var(--nav-item-hover);
}
.tt-nav-btn:focus-visible,
.tt-nav-link:focus-visible {
  outline: 2px solid var(--nav-focus-ring);
  outline-offset: 2px;
}
.tt-nav-btn[aria-expanded="true"],
.tt-nav-btn[data-active-parent="true"],
.tt-nav-link[aria-current="page"] {
  color: var(--nav-cta-bg);
  font-weight: 600;
}
[data-theme="dark"] .tt-nav-btn[aria-expanded="true"],
[data-theme="dark"] .tt-nav-btn[data-active-parent="true"],
[data-theme="dark"] .tt-nav-link[aria-current="page"] {
  color: #818cf8;
}

/* Pure CSS "new" dot on Kids link (no emoji, no text badge) */
.tt-nav-dot-new::after {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--nav-dot-color);
  margin-left: 0.35rem;
  vertical-align: middle;
}

/* Dropdown Chevron */
.tt-chevron {
  width: 0.875rem;
  height: 0.875rem;
  color: var(--nav-text-muted);
  transition: transform 0.2s ease;
  flex-shrink: 0;
}
.tt-nav-btn[aria-expanded="true"] .tt-chevron,
.tt-dropdown-wrap:hover .tt-chevron {
  transform: rotate(180deg);
}

/* Dropdown Wrap & Menus */
.tt-dropdown-wrap {
  position: relative;
}
.tt-dropdown-menu {
  position: absolute;
  top: calc(100% + 4px);
  left: 0;
  background-color: var(--nav-dropdown-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--nav-dropdown-border);
  border-radius: 1rem;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.4), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
  z-index: 1010;
  display: none;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-4px);
  transition: opacity 0.15s ease, transform 0.15s ease, visibility 0.15s ease;
  pointer-events: auto;
}

/* Invisible bridge pseudo-element to prevent hover collapse between button and dropdown */
.tt-dropdown-menu::before {
  content: '';
  position: absolute;
  top: -12px;
  left: 0;
  right: 0;
  height: 12px;
  background: transparent;
}

/* Open State (via hover delay or JS click/focus) */
.tt-dropdown-wrap:hover .tt-dropdown-menu,
.tt-dropdown-wrap:focus-within .tt-dropdown-menu,
.tt-dropdown-menu.tt-menu-open {
  display: block;
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* 2-Column Tests Dropdown (~440px) */
.tt-menu-2col {
  width: 440px;
  max-width: 90vw;
  overflow: hidden;
  box-sizing: border-box;
}
.tt-menu-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.35rem;
  padding: 0.6rem;
  box-sizing: border-box;
}

/* 1-Column Dropdowns (~275px) */
.tt-menu-1col {
  width: 275px;
  padding: 0.5rem;
  box-sizing: border-box;
}
.tt-menu-1col .tt-menu-item + .tt-menu-item {
  margin-top: 0.25rem;
}

/* Menu Item Card */
.tt-menu-item {
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
  padding: 0.55rem 0.65rem;
  border-radius: 0.75rem;
  color: var(--nav-text);
  text-decoration: none;
  transition: background-color 0.15s ease, color 0.15s ease;
}
.tt-menu-item:hover {
  background-color: var(--nav-item-hover);
  color: var(--nav-text-hover);
}
.tt-menu-item:focus-visible {
  outline: 2px solid var(--nav-focus-ring);
  outline-offset: 1px;
}
.tt-menu-item[aria-current="page"] {
  background-color: rgba(99, 102, 241, 0.12);
  border: 1px solid rgba(99, 102, 241, 0.25);
}
[data-theme="dark"] .tt-menu-item[aria-current="page"] .tt-item-title {
  color: #818cf8;
}
[data-theme="light"] .tt-menu-item[aria-current="page"] .tt-item-title {
  color: #4f46e5;
}

.tt-item-icon {
  width: 1.75rem;
  height: 1.75rem;
  border-radius: 0.5rem;
  background-color: rgba(99, 102, 241, 0.1);
  color: #818cf8;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 0.1rem;
}
[data-theme="light"] .tt-item-icon {
  color: #4f46e5;
}
.tt-item-icon svg {
  width: 1rem;
  height: 1rem;
}

.tt-item-title {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--nav-text-hover);
  line-height: 1.25;
}
.tt-item-desc {
  font-size: 0.6875rem;
  color: var(--nav-text-muted);
  margin-top: 0.15rem;
  line-height: 1.2;
}

/* Panel Footer for Tests */
.tt-panel-footer {
  border-top: 1px solid var(--nav-border);
  background-color: var(--nav-panel-footer-bg);
  padding: 0.65rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.75rem;
}
.tt-panel-footer a {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  color: var(--nav-text-muted);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.15s ease;
}
.tt-panel-footer a:hover {
  color: var(--nav-text-hover);
}
.tt-panel-footer a svg {
  width: 0.875rem;
  height: 0.875rem;
}

/* Right-side Action Controls */
.tt-nav-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}
@media (min-width: 640px) {
  .tt-nav-actions { gap: 0.75rem; }
}

/* Theme Toggle Button */
.tt-theme-btn,
.tt-icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 0.75rem;
  background-color: var(--nav-item-hover);
  border: 1px solid var(--nav-border);
  color: var(--nav-text);
  cursor: pointer;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  padding: 0;
}
.tt-theme-btn:hover,
.tt-icon-btn:hover {
  color: var(--nav-text-hover);
  border-color: rgba(99, 102, 241, 0.4);
}
.tt-theme-btn:focus-visible,
.tt-icon-btn:focus-visible {
  outline: 2px solid var(--nav-focus-ring);
  outline-offset: 2px;
}
.tt-theme-btn svg,
.tt-icon-btn svg {
  width: 1.125rem;
  height: 1.125rem;
}

/* Plain "Sign in" Button */
.tt-signin-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.45rem 0.75rem;
  border-radius: 0.75rem;
  color: var(--nav-text);
  background: transparent;
  border: 1px solid transparent;
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  font-family: inherit;
  transition: background-color 0.15s ease, color 0.15s ease;
}
.tt-signin-btn:hover {
  background-color: var(--nav-item-hover);
  color: var(--nav-text-hover);
}
.tt-signin-btn:focus-visible {
  outline: 2px solid var(--nav-focus-ring);
  outline-offset: 2px;
}

/* Filled Primary CTA Button ("Free certificate") */
.tt-btn-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  padding: 0.5rem 1rem;
  border-radius: 0.75rem;
  background-color: var(--nav-cta-bg);
  color: var(--nav-cta-text);
  font-size: 0.8125rem;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.25);
  transition: background-color 0.15s ease, transform 0.15s ease;
  white-space: nowrap;
}
.tt-btn-cta:hover {
  background-color: var(--nav-cta-hover);
  transform: translateY(-1px);
}
.tt-btn-cta:focus-visible {
  outline: 2px solid var(--nav-focus-ring);
  outline-offset: 2px;
}

/* Short "Certificate" button on mobile below 1024px */
.tt-btn-cta-mobile {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.4rem 0.75rem;
  border-radius: 0.75rem;
  background-color: var(--nav-cta-bg);
  color: var(--nav-cta-text);
  font-size: 0.75rem;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}
@media (min-width: 1024px) {
  .tt-btn-cta-mobile { display: none !important; }
}
@media (max-width: 1023px) {
  .tt-btn-cta-desktop { display: none !important; }
}

/* Mobile Hamburger Toggle Button */
.tt-mobile-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 0.75rem;
  background-color: var(--nav-item-hover);
  border: 1px solid var(--nav-border);
  color: var(--nav-text);
  cursor: pointer;
}
@media (min-width: 1024px) {
  .tt-mobile-toggle { display: none !important; }
}
.tt-mobile-toggle:focus-visible {
  outline: 2px solid var(--nav-focus-ring);
  outline-offset: 2px;
}
.tt-mobile-toggle svg {
  width: 1.25rem;
  height: 1.25rem;
}

/* Mobile Header Adjustment */
@media (max-width: 1023px) {
  .tt-header {
    height: var(--nav-height-mobile);
  }
}

/* ==================== MOBILE DRAWER ==================== */
.tt-mobile-drawer {
  display: none;
  position: fixed;
  top: var(--nav-height-mobile);
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--nav-bg);
  border-top: 1px solid var(--nav-border);
  z-index: 1020;
  flex-direction: column;
  justify-content: space-between;
  overflow-y: auto;
  box-sizing: border-box;
}
.tt-mobile-drawer.tt-drawer-open {
  display: flex;
}

body.nav-scroll-lock {
  overflow: hidden !important;
}

.tt-drawer-content {
  padding: 1rem;
  flex-grow: 1;
}

/* Accordion Row (>= 48px tall) */
.tt-accordion-row {
  border-bottom: 1px solid var(--nav-border);
}
.tt-accordion-btn {
  width: 100%;
  min-height: 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 0.5rem;
  background: transparent;
  border: none;
  color: var(--nav-text);
  font-family: inherit;
  font-size: 0.9375rem;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
}
.tt-accordion-btn:focus-visible {
  outline: 2px solid var(--nav-focus-ring);
  outline-offset: -2px;
}
.tt-accordion-btn[aria-expanded="true"] .tt-chevron {
  transform: rotate(180deg);
}

.tt-accordion-panel {
  display: none;
  padding: 0.25rem 0 0.75rem 0.75rem;
  flex-direction: column;
  gap: 0.25rem;
}
.tt-accordion-panel.tt-panel-open {
  display: flex;
}

.tt-mobile-sublink {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  min-height: 44px;
  padding: 0.4rem 0.6rem;
  border-radius: 0.5rem;
  color: var(--nav-text-muted);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
}
.tt-mobile-sublink:hover,
.tt-mobile-sublink[aria-current="page"] {
  color: var(--nav-text-hover);
  background-color: var(--nav-item-hover);
}
.tt-mobile-sublink svg {
  width: 1rem;
  height: 1rem;
  color: #818cf8;
}

/* Mobile Direct Row (Kids) */
.tt-mobile-direct-link {
  width: 100%;
  min-height: 48px;
  display: flex;
  align-items: center;
  padding: 0.75rem 0.5rem;
  color: var(--nav-text);
  text-decoration: none;
  font-size: 0.9375rem;
  font-weight: 600;
}
.tt-mobile-direct-link:hover {
  color: var(--nav-text-hover);
}

/* Pinned Bottom Area in Drawer with Safe-Area Padding */
.tt-drawer-bottom {
  border-top: 1px solid var(--nav-border);
  padding: 1rem;
  padding-bottom: calc(1rem + env(safe-area-inset-bottom, 0px));
  background-color: var(--nav-panel-footer-bg);
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}
.tt-drawer-bottom .tt-btn-cta {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 0.9375rem;
  box-sizing: border-box;
}
.tt-drawer-bottom .tt-signin-btn {
  width: 100%;
  padding: 0.7rem 1rem;
  justify-content: center;
  background-color: var(--nav-item-hover);
  border: 1px solid var(--nav-border);
  font-size: 0.875rem;
  box-sizing: border-box;
}

/* Shared Footer Styling */
.tt-shared-footer {
  border-top: 1px solid var(--nav-border);
  background-color: var(--nav-bg);
  padding: 2.5rem 1rem 3rem 1rem;
  color: var(--nav-text-muted);
  font-size: 0.8125rem;
  margin-top: auto;
}
.tt-footer-container {
  max-width: 80rem;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}
@media (min-width: 768px) {
  .tt-footer-container {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}
.tt-footer-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.tt-footer-brand img {
  height: 28px;
  width: auto;
}
.tt-footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
  align-items: center;
}
.tt-footer-links a {
  color: var(--nav-text-muted);
  text-decoration: none;
  transition: color 0.15s ease;
}
.tt-footer-links a:hover {
  color: var(--nav-text-hover);
}

/* ==================== ACTION FLYOUT MENUS ==================== */
#settings-dropdown-container,
#user-menu-container {
  position: relative;
}

#settings-dropdown-menu,
#user-dropdown-menu {
  position: absolute;
  right: 0;
  top: calc(100% + 8px);
  background-color: var(--nav-dropdown-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--nav-dropdown-border);
  border-radius: 1rem;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.4);
  z-index: 1015;
  box-sizing: border-box;
}

#settings-dropdown-menu {
  width: 290px;
  padding: 0.875rem;
}

#user-dropdown-menu {
  width: 300px;
  padding: 0.875rem;
}

#settings-dropdown-menu.hidden,
#user-dropdown-menu.hidden {
  display: none !important;
}