/* ==================== NAV ==================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  background: rgba(8, 8, 6, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(232, 228, 219, 0.04);
}

.nav__wordmark {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.1rem;
  letter-spacing: -0.04em;
  color: var(--chalk);
  text-decoration: none;
  cursor: pointer;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav__link {
  font-family: var(--font-system);
  font-size: 0.6rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--dim);
  text-decoration: none;
  transition: color var(--transition);
  cursor: pointer;
}

.nav__link:hover {
  color: var(--chalk);
}

.nav__link--active {
  color: var(--chalk);
}

.nav__user {
  font-family: var(--font-system);
  font-size: 0.6rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--acid);
  text-decoration: none;
  cursor: pointer;
}

.nav__lang {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  margin-left: 1rem;
}

.nav__lang-option {
  font-family: var(--font-system);
  font-size: 0.55rem;
  letter-spacing: 0.1em;
  color: var(--dim);
  cursor: pointer;
  padding: 0.2rem 0.4rem;
  border-radius: var(--radius-badge);
  transition: color var(--transition), background var(--transition);
}

.nav__lang-option:hover {
  color: var(--chalk);
}

.nav__lang-option--active {
  color: var(--chalk);
  background: rgba(232, 228, 219, 0.08);
}

/* ==================== BUTTONS ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.9rem;
  border: none;
  border-radius: var(--radius-button);
  cursor: pointer;
  transition: all var(--transition);
  text-decoration: none;
}

.btn--signal {
  background: var(--signal);
  color: var(--black);
}

.btn--signal:hover {
  background: var(--signal-deep);
  color: var(--chalk);
}

.btn--acid {
  background: var(--acid);
  color: var(--black);
}

.btn--acid:hover {
  background: var(--acid-deep);
  color: var(--black);
}

.btn--ghost {
  background: transparent;
  color: var(--chalk);
  border: 1px solid rgba(232, 228, 219, 0.1);
}

.btn--ghost:hover {
  border-color: rgba(232, 228, 219, 0.25);
}

.btn--small {
  padding: 0.5rem 1rem;
  font-size: 0.8rem;
}

.btn--danger {
  background: transparent;
  color: var(--signal);
  border: 1px solid rgba(255, 79, 26, 0.25);
}

.btn--danger:hover {
  background: rgba(255, 79, 26, 0.1);
  border-color: var(--signal);
}

/* ==================== CONCEPT CARDS ==================== */
.concept-card {
  background: var(--off);
  border: 1px solid rgba(232, 228, 219, 0.05);
  border-radius: var(--radius-card);
  padding: 1.75rem;
  cursor: pointer;
  transition: border-color var(--transition), transform var(--transition);
  position: relative;
  overflow: hidden;
}

.concept-card:hover {
  border-color: rgba(232, 228, 219, 0.12);
  transform: translateY(-3px);
}

.concept-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 0;
  transition: height 0.4s ease;
}

.concept-card:hover::before {
  height: 100%;
}

.concept-card[data-state="activated"]::before {
  background: var(--signal);
}

.concept-card[data-state="adjacent"]::before {
  background: var(--acid);
}

.concept-card[data-state="unexplored"]::before {
  background: var(--dim);
}

.concept-card__relation {
  font-family: var(--font-voice);
  font-style: italic;
  font-size: 0.75rem;
  color: var(--dim);
  margin-bottom: 0.5rem;
}

.concept-card__title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.concept-card[data-state="activated"] .concept-card__title {
  color: var(--signal);
}

.concept-card[data-state="adjacent"] .concept-card__title {
  color: var(--acid);
}

.concept-card[data-state="unexplored"] .concept-card__title {
  color: var(--chalk);
}

.concept-card__summary {
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--bone);
}

.concept-card__state {
  font-family: var(--font-system);
  font-size: 0.5rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--dim);
  margin-top: 1rem;
}

.concept-card__description {
  font-family: var(--font-voice);
  font-style: italic;
  font-size: 0.85rem;
  line-height: 1.6;
  color: var(--bone);
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid rgba(232, 228, 219, 0.06);
}

.concept-card__edit-desc {
  background: none;
  border: none;
  font-family: var(--font-system);
  font-size: 0.5rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--dim);
  cursor: pointer;
  padding: 0;
  margin-top: 0.5rem;
  transition: color var(--transition);
}

.concept-card__edit-desc:hover {
  color: var(--signal);
}

/* ==================== INPUTS ==================== */
select {
  color-scheme: dark;
}

select option {
  background: var(--off);
  color: var(--chalk);
}

.input {
  width: 100%;
  padding: 0.75rem 1rem;
  background: var(--off);
  border: 1px solid rgba(232, 228, 219, 0.08);
  border-radius: var(--radius-button);
  color: var(--chalk);
  font-family: var(--font-display);
  font-size: 0.95rem;
  outline: none;
  transition: border-color var(--transition);
}

.input:focus {
  border-color: var(--signal);
}

.input::placeholder {
  color: var(--dim);
}

.form-group {
  margin-bottom: 1.25rem;
}

.form-group__label {
  display: block;
  font-family: var(--font-system);
  font-size: 0.55rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--dim);
  margin-bottom: 0.5rem;
}

.form-error {
  font-family: var(--font-system);
  font-size: 0.65rem;
  color: var(--signal);
  margin-top: 0.5rem;
}

/* ==================== MODAL ==================== */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(8, 8, 6, 0.8);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
}

.modal {
  background: var(--off);
  border: 1px solid rgba(232, 228, 219, 0.06);
  border-radius: var(--radius-card);
  padding: 2.5rem;
  width: 100%;
  max-width: 420px;
  position: relative;
}

.modal__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.5rem;
  letter-spacing: -0.03em;
  margin-bottom: 0.5rem;
}

.modal__subtitle {
  font-family: var(--font-voice);
  font-style: italic;
  color: var(--bone);
  margin-bottom: 2rem;
}

.modal__close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: none;
  border: none;
  color: var(--dim);
  cursor: pointer;
  font-size: 1.2rem;
  padding: 0.5rem;
  transition: color var(--transition);
}

.modal__close:hover {
  color: var(--chalk);
}

.modal__switch {
  margin-top: 1.5rem;
  font-size: 0.85rem;
  color: var(--dim);
  text-align: center;
}

.modal__switch a {
  color: var(--signal);
  cursor: pointer;
}

/* ==================== STATS ==================== */
.stats {
  font-family: var(--font-system);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--dim);
}

.stats__value {
  color: var(--chalk);
}