/* ========================================
   Gradify Web – Component Styles
   Cards, Buttons, Nav, Chips, Modals, etc.
   ======================================== */

/* ── App Top Navigation Bar ─────────────── */
.app-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--color-main-bg);
  border-bottom: 1px solid var(--color-divider);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--spacing-md);
  z-index: var(--z-sticky);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.app-nav .nav-logo {
  font-weight: var(--font-weight-bold);
  font-size: var(--font-size-lg);
  color: var(--color-text-icons);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.app-nav .nav-logo span.accent {
  color: var(--color-glow);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.nav-icon-btn {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  color: var(--color-text-icons);
  transition:
    background var(--transition-fast),
    transform var(--transition-spring);
  cursor: pointer;
}

.nav-icon-btn:hover {
  background: var(--color-email-pill-bg);
  transform: scale(1.1);
}

.nav-avatar {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-full);
  overflow: hidden;
  border: 2px solid var(--color-hero-cards);
  cursor: pointer;
  transition:
    transform var(--transition-spring),
    box-shadow var(--transition-base);
}

.nav-avatar:hover {
  transform: scale(1.08);
  box-shadow: var(--shadow-glow);
}

.nav-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ── Side Drawer / Nav Panel ─────────────── */
.sidebar-overlay {
  position: fixed;
  inset: 0;
  background: rgba(34, 51, 59, 0.5);
  backdrop-filter: blur(6px);
  z-index: var(--z-overlay);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base);
}

.sidebar-overlay.active {
  opacity: 1;
  pointer-events: all;
}

.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--color-tray-bg);
  color: var(--color-main-bg);
  z-index: var(--z-modal);
  display: flex;
  flex-direction: column;
  transform: translateX(-100%);
  transition: transform var(--transition-base);
  overflow-y: auto;
}

.sidebar.open {
  transform: translateX(0);
}

.sidebar-header {
  padding: var(--spacing-lg) var(--spacing-md);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.sidebar-profile {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  cursor: pointer;
  border-radius: var(--radius-md);
  transition: background var(--transition-fast);
}

.sidebar-profile:hover {
  background: rgba(255, 255, 255, 0.08);
}

.sidebar-profile-avatar {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-full);
  overflow: hidden;
  border: 2px solid var(--color-hero-cards);
  flex-shrink: 0;
}

.sidebar-profile-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.sidebar-profile-name {
  font-weight: var(--font-weight-semi);
  font-size: var(--font-size-md);
  color: var(--color-main-bg);
}

.sidebar-profile-sub {
  font-size: var(--font-size-xs);
  color: rgba(250, 246, 233, 0.6);
  margin-top: 2px;
}

.sidebar-nav {
  padding: var(--spacing-sm) 0;
  flex: 1;
}

.sidebar-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-sm) var(--spacing-md);
  color: rgba(250, 246, 233, 0.85);
  cursor: pointer;
  border-radius: var(--radius-sm);
  margin: 2px var(--spacing-sm);
  transition:
    background var(--transition-fast),
    color var(--transition-fast);
  font-size: var(--font-size-sm);
}

.sidebar-item:hover,
.sidebar-item.active {
  background: rgba(221, 232, 157, 0.15);
  color: var(--color-hero-cards);
}

.sidebar-item .icon {
  font-size: 18px;
  width: 24px;
  text-align: center;
}

.sidebar-divider {
  height: 1px;
  background: rgba(255, 255, 255, 0.1);
  margin: var(--spacing-sm) var(--spacing-md);
}

.sidebar-exam-countdown {
  padding: var(--spacing-md);
  background: rgba(221, 232, 157, 0.1);
  border-radius: var(--radius-md);
  margin: var(--spacing-sm) var(--spacing-md);
}

.exam-timer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 6px;
}

.exam-timer-row:last-child {
  margin-bottom: 0;
}

/* ── Badges ──────────────────────────────── */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 11px;
  font-weight: 700;
  background: var(--color-hero-cards);
  color: var(--color-tray-bg);
  white-space: nowrap;
}

.badge-dark {
  background: rgba(0, 0, 0, 0.25);
  color: var(--color-hero-cards);
}

.sidebar-footer {
  padding: var(--spacing-md);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* ── Cards ───────────────────────────────── */
.card {
  background: var(--color-card-bg);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  transition:
    transform var(--transition-spring),
    box-shadow var(--transition-base);
  position: relative;
  overflow: hidden;
}

.card:hover {
  transform: translateY(-3px) scale(1.01);
  box-shadow: var(--shadow-md);
}

.card--hero {
  background: var(--color-hero-cards);
  color: var(--color-text-icons);
}

.card--dark {
  background: var(--color-tray-bg);
  color: var(--color-main-bg);
}

.card--clickable {
  cursor: pointer;
}

.card--clickable:active {
  transform: scale(0.98);
  box-shadow: var(--shadow-xs);
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--color-email-pill-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  margin-bottom: var(--spacing-sm);
}

.card-title {
  font-weight: var(--font-weight-semi);
  font-size: var(--font-size-md);
  margin-bottom: 4px;
}

.card-sub {
  font-size: var(--font-size-sm);
  opacity: 0.65;
}

/* Dashboard grid */
.dashboard-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
}

.dash-card:first-child {
  grid-column: span 2;
}

@media (min-width: 768px) {
  .dashboard-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.card-action-btn {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 28px;
  height: 28px;
  border-radius: var(--radius-full);
  background: rgba(0, 0, 0, 0.04);
  color: var(--color-text-icons);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  border: none;
  cursor: pointer;
  z-index: 10;
  transition: background var(--transition-fast);
}

.card-action-btn:hover {
  background: rgba(0, 0, 0, 0.08);
}

/* ── Buttons ──────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-full);
  font-weight: var(--font-weight-semi);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: all var(--transition-spring);
  white-space: nowrap;
  user-select: none;
  -webkit-user-select: none;
}

.btn:active {
  transform: scale(0.96);
}

.btn-primary {
  background: var(--color-tray-bg);
  color: var(--color-main-bg);
}
.btn-primary:hover {
  background: var(--color-primary);
  box-shadow: var(--shadow-md);
}

.btn-accent {
  background: var(--color-hero-cards);
  color: var(--color-text-icons);
}
.btn-accent:hover {
  filter: brightness(1.05);
  box-shadow: var(--shadow-md);
}

.btn-ghost {
  background: transparent;
  color: var(--color-text-icons);
  border: 1.5px solid var(--color-divider);
}
.btn-ghost:hover {
  background: var(--color-email-pill-bg);
}

.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: var(--radius-full);
}

.btn-lg {
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: var(--font-size-base);
}

.btn-block {
  width: 100%;
}

/* Loading state */
.btn.loading .btn-text {
  opacity: 0;
}
.btn.loading::after {
  content: "";
  position: absolute;
  width: 18px;
  height: 18px;
  border: 2px solid currentColor;
  border-top-color: transparent;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

/* ── Chips ────────────────────────────────── */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
  cursor: pointer;
  border: 1.5px solid var(--color-divider);
  background: var(--color-card-bg);
  color: var(--color-text-icons);
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.chip.active,
.chip:hover {
  background: var(--color-tray-bg);
  color: var(--color-main-bg);
  border-color: var(--color-tray-bg);
}

.chips-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-md);
}

/* ── Form Controls ──────────────────────── */
.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: var(--spacing-md);
}

.form-label {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-icons);
}

.form-input,
.form-select {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  border: 1.5px solid var(--color-divider);
  background: var(--color-card-bg);
  color: var(--color-text-icons);
  font-size: var(--font-size-base);
  transition:
    border-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

.form-input:focus,
.form-select:focus {
  border-color: var(--color-glow);
  box-shadow: 0 0 0 3px rgba(11, 229, 193, 0.15);
}

.form-textarea {
  resize: vertical;
  min-height: 100px;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  border: 1.5px solid var(--color-divider);
  background: var(--color-card-bg);
  color: var(--color-text-icons);
  font-size: var(--font-size-base);
  font-family: inherit;
  transition: border-color var(--transition-fast);
  width: 100%;
}
.form-textarea:focus {
  border-color: var(--color-glow);
}

/* Toggle / Switch */
.toggle-wrap {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.toggle {
  position: relative;
  width: 48px;
  height: 26px;
  flex-shrink: 0;
}

.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  position: absolute;
  inset: 0;
  background: var(--color-divider);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: background var(--transition-base);
}

.toggle-slider::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 3px;
  width: 20px;
  height: 20px;
  background: white;
  border-radius: 50%;
  transition: transform var(--transition-spring);
  box-shadow: var(--shadow-xs);
}

.toggle input:checked + .toggle-slider {
  background: var(--color-hero-cards);
}
.toggle input:checked + .toggle-slider::before {
  transform: translateX(22px);
}

/* ── Modals ───────────────────────────────── */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(34, 51, 59, 0.55);
  backdrop-filter: blur(8px);
  z-index: var(--z-modal);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-base);
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: all;
}

.modal-sheet {
  width: 100%;
  max-width: 600px;
  max-height: 90vh;
  background: var(--color-card-bg);
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
  padding: var(--spacing-lg);
  overflow-y: auto;
  transform: translateY(100%);
  transition: transform var(--transition-slow);
}

.modal-overlay.active .modal-sheet {
  transform: translateY(0);
}

@media (min-width: 768px) {
  .modal-overlay {
    align-items: center;
  }
  .modal-sheet {
    border-radius: var(--radius-xl);
    max-height: 80vh;
  }
}

.modal-handle {
  width: 40px;
  height: 4px;
  background: var(--color-divider);
  border-radius: var(--radius-full);
  margin: 0 auto var(--spacing-md);
}

/* ── Toast Notifications ────────────────── */
.toast-container {
  position: fixed;
  top: calc(var(--nav-height) + var(--spacing-md));
  right: var(--spacing-md);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  max-width: 320px;
  width: calc(100% - 2 * var(--spacing-md));
}

.toast {
  background: var(--color-tray-bg);
  color: var(--color-main-bg);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  transform: translateX(120%);
  transition: transform var(--transition-spring);
}

.toast.show {
  transform: translateX(0);
}
.toast.success {
  border-left: 4px solid var(--color-success);
}
.toast.error {
  border-left: 4px solid var(--color-error);
}
.toast.info {
  border-left: 4px solid var(--color-glow);
}

/* ── Loading States ───────────────────────── */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--color-email-pill-bg) 25%,
    var(--color-divider) 50%,
    var(--color-email-pill-bg) 75%
  );
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: var(--radius-md);
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--color-divider);
  border-top-color: var(--color-glow);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.page-loader {
  position: fixed;
  inset: 0;
  background: var(--color-main-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  flex-direction: column;
  gap: var(--spacing-md);
  transition: opacity var(--transition-slow);
}

.page-loader.done {
  opacity: 0;
  pointer-events: none;
}

/* ── Progress Bar ─────────────────────────── */
.progress-bar {
  width: 100%;
  height: 6px;
  background: var(--color-email-pill-bg);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(
    90deg,
    var(--color-glow),
    var(--color-hero-cards)
  );
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

/* ── Badge ────────────────────────────────── */
.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 2px 10px;
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semi);
  background: var(--color-hero-cards);
  color: var(--color-text-icons);
}

.badge-dark {
  background: var(--color-tray-bg);
  color: var(--color-main-bg);
}

/* ── Section headers ─────────────────────── */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--spacing-md);
  margin-top: var(--spacing-lg);
}

.section-title {
  font-weight: var(--font-weight-bold);
  font-size: var(--font-size-md);
}

/* ── Divider ──────────────────────────────── */
.divider {
  height: 1px;
  background: var(--color-divider);
  margin: var(--spacing-md) 0;
}

/* ── Empty State ─────────────────────────── */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-3xl) var(--spacing-md);
  text-align: center;
  gap: var(--spacing-md);
}

.empty-state-icon {
  font-size: 64px;
  opacity: 0.4;
}
.empty-state-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-semi);
}
.empty-state-sub {
  font-size: var(--font-size-sm);
  opacity: 0.6;
  max-width: 280px;
}

/* ── Study Timer Badge ─────────────────── */
.study-timer {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  background: var(--color-hero-cards);
  color: var(--color-text-icons);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semi);
  font-variant-numeric: tabular-nums;
}

/* ── Keyframes ───────────────────────────── */
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

@keyframes skeleton-shimmer {
  0% {
    background-position: -200% 0;
  }
  100% {
    background-position: 200% 0;
  }
}

@keyframes pulse {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

@keyframes bounce-in {
  0% {
    transform: scale(0.8);
    opacity: 0;
  }
  60% {
    transform: scale(1.05);
  }
  100% {
    transform: scale(1);
    opacity: 1;
  }
}

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

@keyframes fade-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}