/* =========================================================================
   Application shells: public header, student/admin sidebar, mobile drawer,
   footers and page headers.
   ========================================================================= */

/* ---- public / marketing header ------------------------------------------ */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-bottom: 1px solid transparent;
  transition: border-color var(--duration-base) var(--ease-out),
              box-shadow var(--duration-base) var(--ease-out);
}
/* .is-stuck is toggled by app.js once the page scrolls, so the header only
   grows a border when there is content underneath it. */
.site-header.is-stuck { border-bottom-color: var(--border); box-shadow: var(--shadow-sm); }

.site-header-inner {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  height: var(--header-height);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  font-weight: var(--weight-black);
  font-size: var(--text-lg);
  letter-spacing: var(--tracking-tight);
  color: var(--text);
  flex: none;
}
.brand:hover { text-decoration: none; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 38px; height: 38px;
  border-radius: var(--radius-sm);
  background: var(--gradient-brand);
  color: #fff;
  box-shadow: var(--shadow-brand);
  flex: none;
}
.brand-mark svg { width: 21px; height: 21px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-sub {
  font-size: 0.625rem;
  font-weight: var(--weight-semibold);
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
}

.site-nav { display: none; align-items: center; gap: var(--space-1); }
@media (min-width: 992px) { .site-nav { display: flex; } }

.site-nav-link {
  position: relative;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-sm);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  color: var(--text-muted);
  transition: color var(--duration-fast) var(--ease-out), background-color var(--duration-fast) var(--ease-out);
}
.site-nav-link:hover { color: var(--text); background: var(--bg-sunken); text-decoration: none; }
.site-nav-link.is-active { color: var(--text-brand); font-weight: var(--weight-semibold); }
.site-nav-link.is-active::after {
  content: "";
  position: absolute;
  left: 50%; bottom: 2px;
  transform: translateX(-50%);
  width: 18px; height: 2px;
  border-radius: var(--radius-pill);
  background: var(--brand-500);
}

.site-header-actions { display: flex; align-items: center; gap: var(--space-2); margin-left: auto; }

.nav-toggle {
  display: grid;
  place-items: center;
  width: 42px; height: 42px;
  border-radius: var(--radius-sm);
  color: var(--text);
  transition: background-color var(--duration-fast) var(--ease-out);
}
.nav-toggle:hover { background: var(--bg-sunken); }
@media (min-width: 992px) { .nav-toggle.desktop-hide { display: none; } }

/* Animated hamburger: three lines that fold into an X. */
.burger { position: relative; width: 20px; height: 14px; }
.burger span {
  position: absolute;
  left: 0;
  width: 100%; height: 2px;
  border-radius: var(--radius-pill);
  background: currentColor;
  transition: transform var(--duration-base) var(--ease-spring),
              opacity var(--duration-fast) var(--ease-out),
              top var(--duration-base) var(--ease-spring);
}
.burger span:nth-child(1) { top: 0; }
.burger span:nth-child(2) { top: 6px; }
.burger span:nth-child(3) { top: 12px; }
[aria-expanded="true"] .burger span:nth-child(1) { top: 6px; transform: rotate(45deg); }
[aria-expanded="true"] .burger span:nth-child(2) { opacity: 0; transform: scaleX(0.4); }
[aria-expanded="true"] .burger span:nth-child(3) { top: 6px; transform: rotate(-45deg); }

/* ---- mobile drawer ------------------------------------------------------ */
.drawer-scrim {
  position: fixed;
  inset: 0;
  z-index: var(--z-drawer);
  background: rgba(13, 13, 26, 0.5);
  backdrop-filter: blur(3px);
  -webkit-backdrop-filter: blur(3px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--duration-base) var(--ease-out), visibility var(--duration-base);
}
.drawer-scrim.is-open { opacity: 1; visibility: visible; }

.drawer {
  position: fixed;
  top: 0; right: 0; bottom: 0;
  z-index: calc(var(--z-drawer) + 1);
  width: min(86vw, 340px);
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border-left: 1px solid var(--border);
  box-shadow: var(--shadow-xl);
  transform: translateX(100%);
  transition: transform var(--duration-base) var(--ease-out);
  overflow-y: auto;
  overscroll-behavior: contain;
}
.drawer.is-open { transform: none; }
.drawer-left { right: auto; left: 0; border-left: 0; border-right: 1px solid var(--border); transform: translateX(-100%); }

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: var(--surface);
  z-index: 1;
}
.drawer-body { padding: var(--space-4); flex: 1; }
.drawer-footer { padding: var(--space-4) var(--space-5); border-top: 1px solid var(--border); }

.drawer-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-sm);
  font-weight: var(--weight-medium);
  color: var(--text);
  transition: background-color var(--duration-fast) var(--ease-out), color var(--duration-fast) var(--ease-out);
}
.drawer-link:hover { background: var(--bg-sunken); text-decoration: none; }
.drawer-link.is-active { background: var(--brand-50); color: var(--brand-700); font-weight: var(--weight-semibold); }
.drawer-link svg { width: 19px; height: 19px; flex: none; }

.drawer-section-title {
  padding: var(--space-4) var(--space-4) var(--space-2);
  font-size: var(--text-xs);
  font-weight: var(--weight-bold);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
  color: var(--text-subtle);
}

/* ---- app shell (student and admin) -------------------------------------- */
.app-shell { display: flex; min-height: 100vh; min-height: 100dvh; }

.app-sidebar {
  position: fixed;
  top: 0; left: 0; bottom: 0;
  z-index: var(--z-sticky);
  width: var(--sidebar-width);
  display: none;
  flex-direction: column;
  background: var(--surface);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  overscroll-behavior: contain;
}
@media (min-width: 1024px) { .app-sidebar { display: flex; } }

.app-sidebar-head {
  padding: var(--space-5);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: var(--surface);
  z-index: 1;
}
.app-sidebar-body { padding: var(--space-4) var(--space-3); flex: 1; }
.app-sidebar-foot { padding: var(--space-4); border-top: 1px solid var(--border); }

.nav-section + .nav-section { margin-top: var(--space-5); }
.nav-section-title {
  padding: 0 var(--space-3) var(--space-2);
  font-size: 0.6875rem;
  font-weight: var(--weight-bold);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
  color: var(--text-subtle);
}

.nav-link {
  position: relative;
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3);
  margin-bottom: 2px;
  border-radius: var(--radius-sm);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  color: var(--text-muted);
  transition: background-color var(--duration-fast) var(--ease-out),
              color var(--duration-fast) var(--ease-out),
              transform var(--duration-fast) var(--ease-out);
}
.nav-link:hover { background: var(--bg-sunken); color: var(--text); text-decoration: none; transform: translateX(2px); }
.nav-link.is-active { background: var(--brand-50); color: var(--brand-700); font-weight: var(--weight-semibold); }
.nav-link.is-active::before {
  content: "";
  position: absolute;
  left: -3px; top: 50%;
  transform: translateY(-50%);
  width: 3px; height: 20px;
  border-radius: var(--radius-pill);
  background: var(--brand-500);
}
.nav-link svg { width: 19px; height: 19px; flex: none; }
.nav-link-badge {
  margin-left: auto;
  padding: 1px var(--space-2);
  border-radius: var(--radius-pill);
  background: var(--danger-500);
  color: #fff;
  font-size: 0.6875rem;
  font-weight: var(--weight-bold);
}

.app-content {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}
@media (min-width: 1024px) { .app-content { margin-left: var(--sidebar-width); } }

.app-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  display: flex;
  align-items: center;
  gap: var(--space-4);
  height: var(--header-height);
  padding-inline: var(--space-4);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-bottom: 1px solid var(--border);
}
@media (min-width: 768px) { .app-header { padding-inline: var(--space-6); } }

.app-main { flex: 1; padding: var(--space-6) var(--space-4) var(--space-16); }
@media (min-width: 768px) { .app-main { padding: var(--space-8) var(--space-6) var(--space-20); } }

.app-main-inner { max-width: var(--container-wide); margin-inline: auto; width: 100%; }

/* ---- header widgets ----------------------------------------------------- */
.header-search { position: relative; display: none; flex: 1; max-width: 400px; }
@media (min-width: 768px) { .header-search { display: block; } }

.icon-btn {
  position: relative;
  display: grid;
  place-items: center;
  width: 40px; height: 40px;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  transition: background-color var(--duration-fast) var(--ease-out), color var(--duration-fast) var(--ease-out);
}
.icon-btn:hover { background: var(--bg-sunken); color: var(--text); }
.icon-btn svg { width: 20px; height: 20px; }

.icon-btn-badge {
  position: absolute;
  top: 5px; right: 5px;
  min-width: 17px; height: 17px;
  padding: 0 4px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-pill);
  background: var(--danger-500);
  color: #fff;
  font-size: 0.625rem;
  font-weight: var(--weight-bold);
  border: 2px solid var(--surface);
  line-height: 1;
}

/* ---- dropdown ----------------------------------------------------------- */
.dropdown { position: relative; }
.dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  min-width: 240px;
  padding: var(--space-2);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px) scale(0.98);
  transform-origin: top right;
  transition: opacity var(--duration-fast) var(--ease-out),
              transform var(--duration-fast) var(--ease-out),
              visibility var(--duration-fast);
  z-index: var(--z-overlay);
}
.dropdown.is-open .dropdown-menu { opacity: 1; visibility: visible; transform: none; }
.dropdown-menu-left { right: auto; left: 0; transform-origin: top left; }
.dropdown-menu-wide { min-width: min(360px, calc(100vw - var(--space-8))); }

.dropdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3);
  border-radius: var(--radius-xs);
  font-size: var(--text-base);
  color: var(--text);
  width: 100%;
  text-align: left;
  transition: background-color var(--duration-fast) var(--ease-out);
}
.dropdown-item:hover { background: var(--bg-sunken); text-decoration: none; }
.dropdown-item svg { width: 18px; height: 18px; color: var(--text-muted); flex: none; }
.dropdown-item.is-danger { color: var(--danger-600); }
.dropdown-item.is-danger svg { color: var(--danger-500); }
.dropdown-divider { height: 1px; background: var(--border); margin: var(--space-2) 0; }
.dropdown-head { padding: var(--space-3); border-bottom: 1px solid var(--border); margin-bottom: var(--space-2); }

/* ---- notification list -------------------------------------------------- */
.notif-list { max-height: 380px; overflow-y: auto; }
.notif-item {
  display: flex;
  gap: var(--space-3);
  padding: var(--space-3);
  border-radius: var(--radius-xs);
  transition: background-color var(--duration-fast) var(--ease-out);
}
.notif-item:hover { background: var(--bg-sunken); text-decoration: none; }
.notif-item.is-unread { background: var(--brand-50); }
.notif-icon {
  display: grid;
  place-items: center;
  width: 34px; height: 34px;
  border-radius: var(--radius-sm);
  background: var(--brand-50);
  color: var(--brand-600);
  flex: none;
}
.notif-icon svg { width: 17px; height: 17px; }
.notif-title { font-size: var(--text-base); font-weight: var(--weight-semibold); line-height: var(--leading-snug); }
.notif-text { font-size: var(--text-sm); color: var(--text-muted); }
.notif-time { font-size: var(--text-xs); color: var(--text-subtle); margin-top: 2px; }

/* ---- page header -------------------------------------------------------- */
.page-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--space-4);
  flex-wrap: wrap;
  margin-bottom: var(--space-6);
}
.page-title {
  font-size: var(--text-2xl);
  font-weight: var(--weight-black);
  letter-spacing: var(--tracking-tight);
  animation: fade-up var(--duration-slow) var(--ease-out) both;
}
.page-subtitle {
  color: var(--text-muted);
  margin-top: var(--space-1);
  animation: fade-up var(--duration-slow) var(--ease-out) 70ms both;
}
.page-actions { display: flex; gap: var(--space-2); flex-wrap: wrap; }

.breadcrumbs {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--text-muted);
  margin-bottom: var(--space-3);
  flex-wrap: wrap;
}
.breadcrumbs a { color: var(--text-muted); }
.breadcrumbs a:hover { color: var(--text-brand); }
.breadcrumbs .sep { color: var(--text-subtle); }

/* ---- filter bar --------------------------------------------------------- */
.filter-bar {
  display: grid;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-5);
  box-shadow: var(--shadow-xs);
}
@media (min-width: 768px) {
  .filter-bar { grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); align-items: end; }
  .filter-bar .filter-wide { grid-column: span 2; }
}
.filter-bar .label { font-size: var(--text-xs); margin-bottom: var(--space-1); }
.filter-bar .input, .filter-bar .select { min-height: 40px; padding-block: var(--space-2); }

/* ---- public footer ------------------------------------------------------ */
.site-footer {
  margin-top: var(--space-20);
  padding: var(--space-16) 0 var(--space-8);
  background: var(--bg-inverse);
  color: rgba(255, 255, 255, 0.72);
}
.site-footer h4 {
  color: #fff;
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
  margin-bottom: var(--space-4);
}
.site-footer a { color: rgba(255, 255, 255, 0.72); font-size: var(--text-base); }
.site-footer a:hover { color: #fff; }
.site-footer .brand { color: #fff; }
.footer-grid {
  display: grid;
  gap: var(--space-8);
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr));
}
.footer-bottom {
  margin-top: var(--space-12);
  padding-top: var(--space-6);
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  flex-wrap: wrap;
  font-size: var(--text-sm);
}

/* The disclosure line. It appears on every single page of the platform,
   because a student must never be left unsure who they are dealing with. */
.disclosure {
  padding: var(--space-4) 0;
  font-size: var(--text-sm);
  line-height: var(--leading-snug);
  color: rgba(255, 255, 255, 0.6);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  margin-top: var(--space-6);
}

.app-footer {
  padding: var(--space-6) var(--space-4);
  border-top: 1px solid var(--border);
  font-size: var(--text-sm);
  color: var(--text-muted);
  text-align: center;
}

/* ---- auth shell --------------------------------------------------------- */
.auth-shell {
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  grid-template-columns: 1fr;
}
@media (min-width: 1024px) { .auth-shell { grid-template-columns: 1fr 1fr; } }

.auth-main {
  display: grid;
  place-items: center;
  padding: var(--space-8) var(--space-5) var(--space-12);
  background: var(--bg);
}
.auth-card { width: min(100%, 440px); }

.auth-aside {
  display: none;
  position: relative;
  padding: var(--space-16);
  background: var(--ink-900);
  background-image: var(--gradient-mesh);
  color: #fff;
  overflow: hidden;
  place-content: center;
}
@media (min-width: 1024px) { .auth-aside { display: grid; } }
.auth-aside h2 { color: #fff; font-size: var(--text-3xl); }
.auth-aside p { color: rgba(255, 255, 255, 0.72); }
.auth-aside .brand { color: #fff; }

.auth-points { display: grid; gap: var(--space-5); margin-top: var(--space-10); }
.auth-point { display: flex; gap: var(--space-4); align-items: flex-start; }
.auth-point-icon {
  display: grid;
  place-items: center;
  width: 42px; height: 42px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.14);
  color: #fff;
  flex: none;
}
.auth-point-icon svg { width: 20px; height: 20px; }
.auth-point-title { color: #fff; font-weight: var(--weight-semibold); }
.auth-point-text { font-size: var(--text-sm); color: rgba(255, 255, 255, 0.66); line-height: var(--leading-snug); }