/* === KNOWLEDGE PAGE === */

/* Reuse brand tokens from tokens.css — no new visual system. */

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* --- Hero (matches #calc-hero on calculator page) --- */
.k-hero-title {
  font-family: var(--font-sans);
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-regular);
  line-height: 1.25;
  letter-spacing: var(--letter-spacing-none);
  color: var(--text-1);
  text-align: center;
  max-width: 760px;
  margin: 0 auto;
  font-optical-sizing: auto;
}

.k-hero-title em {
  font-family: var(--font-display);
  font-weight: var(--font-weight-medium);
  font-size: var(--font-size-h2-b);
}

/* --- Search --- */
#k-search {
  padding-top: clamp(3rem, 6vw, 5rem);
  padding-bottom: 0;
}

.k-search {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
}

.k-search-field {
  position: relative;
  width: 100%;
  max-width: 680px;
}

.k-search-icon {
  position: absolute;
  left: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-4);
  pointer-events: none;
}

.k-search-input {
  width: 100%;
  padding: 1rem 1.25rem 1rem 3.25rem;
  font-family: var(--font-body);
  font-size: var(--font-size-lead);
  font-weight: var(--font-weight-regular);
  line-height: 1.6;
  color: var(--text-1);
  background: var(--background-1);
  border: 1px solid var(--line-2);
  border-radius: var(--radius-full);
  outline: none;
  transition: border-color 0.2s, background 0.2s, box-shadow 0.2s;
  box-sizing: border-box;
}

.k-search-input::placeholder {
  color: var(--text-4);
  opacity: 0.5;
}

.k-search-input:focus {
  border-color: var(--accent-1);
  background: var(--background-2);
  box-shadow: 0 0 0 4px var(--accent-3);
}

.k-search-input:focus-visible {
  outline: 2px solid var(--accent-1);
  outline-offset: 2px;
}

.k-search-hint {
  margin-top: 1rem;
  font-size: var(--font-size-note);
  line-height: 1.4;
  color: var(--text-4);
  font-weight: var(--font-weight-regular);
  text-align: center;
  letter-spacing: var(--letter-spacing-none);
}

/* --- Layout: single centered FAQ column --- */
#k-faq {
  padding-top: clamp(2rem, 4vw, 2.5rem);
}

.k-layout {
  max-width: 760px;
  margin: 0 auto;
}

/* --- Category sections --- */
.k-cat {
  padding-top: clamp(2rem, 4vw, 2.5rem) 0;
  border-top: 1px solid var(--line-1);
  scroll-margin-top: 80px;
}

.k-cat:first-child {
  border-top: none;
  padding-top: 0;
}

.k-cat-head {
  margin-bottom: clamp(1.25rem, 3vw, 2rem);
}

.k-cat-num {
  font-family: var(--font-sans);
  font-size: var(--font-size-tag);
  font-weight: var(--font-weight-regular);
  line-height: 1.4;
  letter-spacing: var(--letter-spacing-wide);
  color: var(--accent-1);
  margin-bottom: 0.5rem;
}

.k-cat-title {
  font-family: var(--font-display);
  font-size: var(--font-size-h3);
  font-weight: var(--font-weight-medium);
  font-style: italic;
  line-height: 1.3;
  letter-spacing: var(--letter-spacing-none);
  color: var(--text-1);
  text-align: left;
  margin-bottom: 0.5rem;
  font-optical-sizing: auto;
}

.k-cat-desc {
  font-size: var(--font-size-base);
  color: var(--text-4);
  font-weight: var(--font-weight-regular);
  line-height: 1.75;
  text-align: left;
  max-width: 52ch;
  margin: 0;
}

/* --- Accordion --- */
.k-item {
  border-top: 1px solid var(--line-1);
  scroll-margin-top: 80px;
}

.k-q {
  margin: 0;
  font-weight: var(--font-weight-normal);
}

.k-q-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
  padding: 1.25rem 0;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  font-family: var(--font-body);
  font-size: var(--font-size-lead);
  font-weight: var(--font-weight-medium);
  color: var(--text-1);
  line-height: 1.6;
  transition: color 0.2s;
}

.k-q-btn:hover {
  color: var(--accent-1);
}

.k-q-btn:focus-visible {
  outline: 2px solid var(--accent-1);
  outline-offset: 4px;
  border-radius: 2px;
}

.k-q-btn[aria-expanded="true"] {
  color: var(--accent-1);
}

/* Plus / minus icon */
.k-icon {
  position: relative;
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  color: currentColor;
}

.k-icon::before,
.k-icon::after {
  content: '';
  position: absolute;
  background: currentColor;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.k-icon::before {
  top: 50%;
  left: 0;
  right: 0;
  height: 1.5px;
  transform: translateY(-50%);
}

.k-icon::after {
  left: 50%;
  top: 0;
  bottom: 0;
  width: 1.5px;
  transform: translateX(-50%);
}

.k-q-btn[aria-expanded="true"] .k-icon::after {
  transform: translateX(-50%) scaleY(0);
  opacity: 0;
}

/* Smooth grid-rows reveal */
.k-a {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.35s ease;
}

.k-a.open {
  grid-template-rows: 1fr;
}

.k-a-inner {
  overflow: hidden;
}

.k-a p {
  font-size: var(--font-size-base);
  color: var(--text-2);
  font-weight: var(--font-weight-regular);
  line-height: 1.75;
  text-align: left;
  max-width: 64ch;
  margin: 0 0 1rem;
  letter-spacing: var(--letter-spacing-none);
}

.k-a p:last-child {
  margin-bottom: 1.5rem;
}

.k-a .k-formula {
  font-family: var(--font-body);
  color: var(--text-1);
  font-weight: var(--font-weight-medium);
  background: var(--background-2);
  border: 1px solid var(--line-1);
  border-radius: var(--radius-card-2);
  padding: 0.875rem 1.125rem;
  line-height: 1.6;
}

.k-a .k-points {
  list-style: none;
  padding: 0;
  margin: 0 0 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.k-a .k-points li {
  font-size: var(--font-size-base);
  color: var(--text-1);
  font-weight: var(--font-weight-regular);
  padding-left: 1.75rem;
  position: relative;
  text-align: left;
}

.k-a .k-points li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent-1);
}

.k-a .k-steps {
  list-style: none;
  padding: 0;
  margin: 0 0 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  counter-reset: none;
}

.k-a .k-steps li {
  font-size: var(--font-size-base);
  color: var(--text-1);
  font-weight: var(--font-weight-regular);
  line-height: 1.75;
  text-align: left;
  padding-left: 0;
}

.k-step-tag {
  display: block;
  font-family: var(--font-sans);
  font-size: var(--font-size-tag);
  letter-spacing: var(--letter-spacing-wide);
  line-height: 1.4;
  text-transform: uppercase;
  color: var(--accent-1);
  font-weight: var(--font-weight-regular);
  margin-bottom: 0.125rem;
}

.k-breakdown {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line-1);
  border-radius: var(--radius-card-2);
  padding: 0.25rem 1.125rem;
  margin: 0 0 1.5rem;
  max-width: 460px;
  background: var(--background-2);
}

.k-breakdown-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 0.625rem 0;
  border-bottom: 1px solid var(--line-1);
  font-size: var(--font-size-base);
  color: var(--text-2);
  font-weight: var(--font-weight-regular);
  line-height: 1.75;
}

.k-breakdown-row:last-child {
  border-bottom: none;
}

.k-breakdown-row span:last-child {
  font-family: var(--font-sans);
  color: var(--text-1);
  font-weight: var(--font-weight-medium);
  text-align: right;
}

.k-breakdown-total {
  border-top: 1px dashed var(--line-2);
  margin-top: 0.25rem;
  padding-top: 0.75rem;
}

.k-breakdown-total span {
  color: var(--text-1) !important;
  font-weight: var(--font-weight-medium) !important;
}

.k-breakdown-total span:last-child {
  color: var(--positive) !important;
}

/* --- Empty state --- */
.k-empty {
  display: none;
  text-align: center;
  padding: clamp(3.5rem, 6vw, 6rem) 0;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

.k-empty.show {
  display: flex;
}

.k-empty-title {  
  font-family: var(--font-body);
  font-size: var(--font-size-lead);
  font-weight: var(--font-weight-medium);
  color: var(--text-1);
  line-height: 1.6;
  letter-spacing: var(--letter-spacing-none);
  text-align: center;
}

.k-empty-copy {
  font-size: var(--font-size-base);
  color: var(--text-4);
  font-weight: var(--font-weight-regular);
  line-height: 1.75;
  text-align: center;
}

/* --- Final CTA (reuse #cta dark treatment) --- */
#k-cta {
  background: var(--background-4);
  position: relative;
  overflow: hidden;
}

#k-cta .wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

#k-cta h2 {
  color: var(--text-3);
  line-height: 1.25;
  max-width: 760px;
}

#k-cta .body-lg {
  color: var(--text-4);
  max-width: clamp(100%, 90vw, 560px);
}

@media (prefers-reduced-motion: reduce) {
  .k-a {
    transition: none;
  }
}