/* IADU Components — filled in during Phase 6 */
/* Buttons, cards, tags, pricing tables, accordions, tabs, forms */

/* ─── Buttons ─────────────────────────────────────────────── */

.iadu-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-sm);
  font-weight: 600;
  border-radius: var(--radius);
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition:
    background-color var(--transition),
    color var(--transition),
    border-color var(--transition),
    box-shadow var(--transition);
  white-space: nowrap;
  line-height: 1;
}

.iadu-btn--primary {
  background-color: var(--color-accent);
  color: var(--color-white);
  border-color: var(--color-accent);
}

.iadu-btn--primary:hover {
  background-color: var(--color-accent-hover);
  border-color: var(--color-accent-hover);
  color: var(--color-white);
  box-shadow: 0 4px 12px rgba(29, 111, 164, 0.35);
}

.iadu-btn--secondary {
  background-color: transparent;
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.iadu-btn--secondary:hover {
  background-color: var(--color-accent);
  color: var(--color-white);
}

.iadu-btn--ghost {
  background-color: transparent;
  color: var(--color-text-on-dark);
  border-color: var(--color-dark-border);
}

.iadu-btn--ghost:hover {
  background-color: var(--color-dark-3);
  color: var(--color-text-on-dark);
}

.iadu-btn--sm {
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-xs);
}

.iadu-btn--lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-base);
}

.iadu-btn .icon {
  width: 16px;
  height: 16px;
}

/* ─── Tags / Badges ───────────────────────────────────────── */

.iadu-tag {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1) var(--space-2);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  border-radius: var(--radius-sm);
  white-space: nowrap;
}

.iadu-tag--paper  { background: var(--color-accent-light); color: var(--color-tag-paper); }
.iadu-tag--report { background: #F0FDF4; color: var(--color-tag-report); }
.iadu-tag--book   { background: #F5F3FF; color: var(--color-tag-book); }
.iadu-tag--course { background: #FFFBEB; color: var(--color-tag-course); }

/* ─── Footer ──────────────────────────────────────────────── */

.iadu-footer {
  padding-block: var(--space-16) var(--space-8);
}

.iadu-footer__top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.iadu-footer__tagline {
  font-size: var(--text-sm);
  color: var(--color-text-on-dark-2);
  margin-top: var(--space-3);
  margin-bottom: var(--space-6);
}

.iadu-footer__social {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.iadu-footer__social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  color: var(--color-text-on-dark-2);
  border: 1px solid var(--color-dark-border);
  border-radius: var(--radius);
  transition: color var(--transition), border-color var(--transition), background-color var(--transition);
  text-decoration: none;
}

.iadu-footer__social-link:hover {
  color: var(--color-text-on-dark);
  border-color: var(--color-accent);
  background-color: var(--color-dark-3);
}

.iadu-footer__social-link .icon--social {
  width: 16px;
  height: 16px;
}

.iadu-footer__social-text {
  font-size: 0.6rem;
  font-weight: 700;
  letter-spacing: var(--tracking-wide);
}

.iadu-footer__col-title {
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
  color: var(--color-text-on-dark-2);
  margin-bottom: var(--space-4);
}

.iadu-footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.iadu-footer__links a {
  font-size: var(--text-sm);
  color: var(--color-text-on-dark-2);
  text-decoration: none;
  transition: color var(--transition);
}

.iadu-footer__links a:hover {
  color: var(--color-text-on-dark);
}

.iadu-footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-6);
}

.iadu-footer__copy {
  font-size: var(--text-xs);
  color: var(--color-text-on-dark-2);
}

@media (max-width: 1024px) {
  .iadu-footer__top {
    grid-template-columns: 1fr 1fr;
  }
  .iadu-footer__brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 640px) {
  .iadu-footer__top {
    grid-template-columns: 1fr;
  }
}

/* ─── Search overlay ──────────────────────────────────────── */

.iadu-search-overlay {
  position: fixed;
  inset: 0;
  z-index: calc(var(--nav-z) + 10);
  background: rgba(14, 14, 18, 0.96);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-med), visibility var(--transition-med);
}

.iadu-search-overlay.is-open {
  opacity: 1;
  visibility: visible;
}

.iadu-search-overlay__inner {
  width: 100%;
  max-width: 720px;
  padding: var(--space-6);
  position: relative;
}

.iadu-search-overlay__inner form {
  display: flex;
  align-items: center;
  border-bottom: 2px solid var(--color-dark-border);
  padding-bottom: var(--space-4);
  transition: border-color var(--transition);
}

.iadu-search-overlay__inner form:focus-within {
  border-color: var(--color-accent);
}

.iadu-search-overlay__inner input[type="search"] {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  color: var(--color-text-on-dark);
  font-size: var(--text-3xl);
  font-weight: 300;
  padding: var(--space-2) 0;
  caret-color: var(--color-accent);
}

.iadu-search-overlay__inner input[type="search"]::placeholder {
  color: var(--color-text-on-dark-2);
}

.iadu-search-overlay__inner button[type="submit"] {
  color: var(--color-text-on-dark-2);
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
}

.iadu-search-overlay__inner button[type="submit"] .icon {
  width: 28px;
  height: 28px;
}

.iadu-search-close {
  position: absolute;
  top: 0;
  right: var(--space-6);
  color: var(--color-text-on-dark-2);
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
  transition: color var(--transition);
}

.iadu-search-close:hover { color: var(--color-text-on-dark); }

.iadu-search-close .icon {
  width: 24px;
  height: 24px;
}

/* ─── Cards — shared base ─────────────────────────────────── */

.iadu-card {
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: box-shadow var(--transition), transform var(--transition);
}

.iadu-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

/* Research card */

.iadu-card--research {
  background: var(--color-white);
  border: 1px solid var(--color-light-border);
  padding: var(--space-6);
  gap: var(--space-3);
}

.iadu-card__authors {
  font-size: var(--text-xs);
  font-weight: 500;
  color: var(--color-text-secondary);
  margin: 0;
}

.iadu-card__journal {
  font-size: var(--text-xs);
  font-style: italic;
  color: var(--color-text-secondary);
}

.iadu-card__meta-sep {
  color: var(--color-text-light);
  margin-inline: var(--space-1);
}

.iadu-card__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-top: auto;
  padding-top: var(--space-3);
}

.iadu-card__action-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--color-light-border);
  border-radius: var(--radius);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition), border-color var(--transition);
}

.iadu-card__action-icon:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.iadu-card__action-icon .icon {
  width: 14px;
  height: 14px;
}

/* Book card */

.iadu-card--book {
  background: var(--color-white);
  border: 1px solid var(--color-light-border);
}

.iadu-card__cover {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 4;
  overflow: hidden;
  background: var(--color-light);
  flex-shrink: 0;
}

.iadu-card__cover-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-med);
}

.iadu-card--book:hover .iadu-card__cover-img {
  transform: scale(1.03);
}

.iadu-card__cover--placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-light);
}

.iadu-card__cover--placeholder .icon {
  width: 48px;
  height: 48px;
}

.iadu-card__body {
  padding: var(--space-5) var(--space-6) var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  flex: 1;
}

.iadu-card__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-top: auto;
  padding-top: var(--space-3);
}

/* Course card */

.iadu-card--course {
  background: var(--color-white);
  border: 1px solid var(--color-light-border);
}

.iadu-card__thumb {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--color-light);
  flex-shrink: 0;
}

.iadu-card__thumb-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-med);
}

.iadu-card--course:hover .iadu-card__thumb-img {
  transform: scale(1.03);
}

.iadu-card__thumb--placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-light);
  background: var(--color-light-gray);
}

.iadu-card__thumb--placeholder .icon {
  width: 40px;
  height: 40px;
}

/* Topic badges on expert card */

.iadu-expert-card__topics {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin-top: var(--space-2);
}

/* ─── Pricing table ───────────────────────────────────────── */

.iadu-pricing-table {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
  align-items: start;
}

@media (max-width: 900px) {
  .iadu-pricing-table {
    grid-template-columns: 1fr;
    max-width: 440px;
    margin-inline: auto;
  }
}

.iadu-pricing-card {
  background: var(--color-white);
  border: 1px solid var(--color-light-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  position: relative;
}

.iadu-pricing-card--featured {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(29, 111, 164, 0.12);
}

.iadu-pricing-card__badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-accent);
  color: var(--color-white);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  padding: 3px 12px;
  border-radius: 999px;
  white-space: nowrap;
}

.iadu-pricing-card__name {
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-text-secondary);
  margin: 0;
}

.iadu-pricing-card__price-row {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  margin-top: var(--space-2);
}

.iadu-pricing-card__price {
  font-size: var(--text-4xl);
  font-weight: 800;
  color: var(--color-text-primary);
  line-height: 1;
}

.iadu-pricing-card__period {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.iadu-pricing-card__features {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  flex: 1;
}

.iadu-pricing-card__feature {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.iadu-pricing-card__feature .icon {
  width: 16px;
  height: 16px;
  color: var(--color-tag-report);
  flex-shrink: 0;
  margin-top: 2px;
}

.iadu-pricing-card__cta {
  width: 100%;
  justify-content: center;
}

/* ─── Accordion ───────────────────────────────────────────── */

.iadu-accordion {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.iadu-accordion__item {
  border-bottom: 1px solid var(--color-light-border);
}

.iadu-accordion__item:first-child {
  border-top: 1px solid var(--color-light-border);
}

.iadu-accordion--dark .iadu-accordion__item {
  border-color: var(--color-dark-border);
}

.iadu-accordion__trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-5) 0;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-text-primary);
  transition: color var(--transition);
}

.iadu-accordion--dark .iadu-accordion__trigger {
  color: var(--color-text-on-dark);
}

.iadu-accordion__trigger:hover {
  color: var(--color-accent);
}

.iadu-accordion__icon {
  flex-shrink: 0;
  color: var(--color-text-secondary);
  transition: transform var(--transition-med);
}

.iadu-accordion__icon .icon {
  width: 18px;
  height: 18px;
  display: block;
}

.iadu-accordion__item.is-open .iadu-accordion__icon {
  transform: rotate(180deg);
}

.iadu-accordion__panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-med);
}

.iadu-accordion__body {
  padding-bottom: var(--space-5);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.iadu-accordion--dark .iadu-accordion__body {
  color: var(--color-text-on-dark-2);
}

/* ─── Tabs ────────────────────────────────────────────────── */

.iadu-tabs__nav {
  display: flex;
  border-bottom: 1px solid var(--color-light-border);
  overflow-x: auto;
  scrollbar-width: none;
  gap: 0;
}

.iadu-tabs__nav::-webkit-scrollbar { display: none; }

.iadu-tabs__trigger {
  padding: var(--space-3) var(--space-5);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  cursor: pointer;
  white-space: nowrap;
  transition: color var(--transition), border-color var(--transition);
}

.iadu-tabs__trigger:hover {
  color: var(--color-text-primary);
}

.iadu-tabs__trigger.is-active {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
  font-weight: 600;
}

.iadu-tabs__panels {
  padding-top: var(--space-6);
}

.iadu-tabs__panel {
  animation: iadu-fade-in 200ms ease;
}

@keyframes iadu-fade-in {
  from { opacity: 0; transform: translateY(4px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ─── Breadcrumb ──────────────────────────────────────────── */

.iadu-breadcrumb {
  padding: var(--space-3) 0;
}

.iadu-breadcrumb__list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-1);
}

.iadu-breadcrumb__item {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-xs);
  color: var(--color-text-secondary);
}

.iadu-breadcrumb__link {
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition);
}

.iadu-breadcrumb__link:hover {
  color: var(--color-accent);
}

.iadu-breadcrumb__item--current {
  color: var(--color-text-primary);
  font-weight: 500;
}

.iadu-breadcrumb__sep {
  color: var(--color-text-light);
  font-size: var(--text-xs);
}

/* ─── Email opt-in ────────────────────────────────────────── */

.iadu-optin {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-10);
  padding: var(--space-10) var(--space-12);
  background: var(--color-light-gray);
  border-radius: var(--radius-lg);
}

.iadu-optin--dark {
  background: var(--color-dark-3);
  border: 1px solid var(--color-dark-border);
}

.iadu-optin__title {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text-primary);
  margin: 0 0 var(--space-2);
}

.iadu-optin--dark .iadu-optin__title {
  color: var(--color-text-on-dark);
}

.iadu-optin__desc {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  margin: 0;
  max-width: 400px;
}

.iadu-optin--dark .iadu-optin__desc {
  color: var(--color-text-on-dark-2);
}

.iadu-optin__form {
  flex-shrink: 0;
}

.iadu-optin__fields {
  display: flex;
  gap: var(--space-3);
  align-items: center;
}

.iadu-optin__input {
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-light-border);
  border-radius: var(--radius);
  font-size: var(--text-sm);
  color: var(--color-text-primary);
  background: var(--color-white);
  outline: none;
  width: 260px;
  transition: border-color var(--transition);
}

.iadu-optin--dark .iadu-optin__input {
  background: var(--color-dark-2);
  border-color: var(--color-dark-border);
  color: var(--color-text-on-dark);
}

.iadu-optin__input:focus {
  border-color: var(--color-accent);
}

.iadu-optin__privacy {
  font-size: var(--text-xs);
  color: var(--color-text-light);
  margin: var(--space-2) 0 0;
  text-align: center;
}

@media (max-width: 900px) {
  .iadu-optin {
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-8);
  }
  .iadu-optin__input {
    width: 100%;
  }
  .iadu-optin__fields {
    flex-direction: column;
    width: 100%;
  }
  .iadu-optin__fields .iadu-btn {
    width: 100%;
    justify-content: center;
  }
}