.btn,
form [type="submit"] {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: linear-gradient(180deg, var(--accent) 0%, var(--accent-strong) 100%);
  color: var(--text-inverse);
  border: 0;
  border-radius: var(--radius-sm);
  padding: 0.45rem 0.85rem;
  font-size: 0.83rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  cursor: pointer;
  line-height: 1.4;
  text-decoration: none;
  transition:
    background var(--dur-fast) var(--ease-out),
    box-shadow var(--dur-fast) var(--ease-out),
    transform  var(--dur-fast) var(--ease-out);
  box-shadow:
    0 1px 1px rgba(15, 15, 20, 0.10),
    0 1px 4px rgba(59, 110, 248, 0.25),
    inset 0 1px 0 rgba(255, 255, 255, 0.20);
}

.btn:hover,
form [type="submit"]:hover {
  background: linear-gradient(180deg, #4a7afa 0%, #1f48b8 100%);
  text-decoration: none;
  color: var(--text-inverse);
  box-shadow:
    0 2px 4px rgba(15, 15, 20, 0.10),
    0 4px 12px rgba(59, 110, 248, 0.30),
    inset 0 1px 0 rgba(255, 255, 255, 0.22);
}

.btn:active,
form [type="submit"]:active {
  transform: translateY(1px);
  box-shadow:
    0 0 0 1px rgba(15, 15, 20, 0.06),
    inset 0 1px 2px rgba(15, 15, 20, 0.15);
}

.btn:focus-visible,
form [type="submit"]:focus-visible {
  outline: none;
  box-shadow:
    0 0 0 3px var(--accent-glow),
    0 2px 4px rgba(15, 15, 20, 0.10);
}

.btn.secondary,
form [type="submit"].secondary {
  background: var(--surface-1);
  color: var(--text-strong);
  border: 1px solid var(--line-medium);
  box-shadow: var(--shadow-xs);
}

.btn.secondary:hover,
form [type="submit"].secondary:hover {
  background: var(--surface-2);
  color: var(--text-strong);
  border-color: var(--line-strong);
  box-shadow: var(--shadow-sm);
}

.btn-sm {
  padding: 0.28rem 0.6rem;
  font-size: 0.78rem;
  border-radius: var(--radius-xs);
  font-weight: 600;
}

.btn-danger {
  background: linear-gradient(180deg, #e25e5e 0%, #c53030 100%);
  box-shadow:
    0 1px 1px rgba(15, 15, 20, 0.10),
    0 1px 4px rgba(229, 62, 62, 0.25);
}

.btn-danger:hover {
  background: linear-gradient(180deg, #ec6a6a 0%, #a32626 100%);
}

.btn-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid var(--line-medium);
  border-radius: var(--radius-xs);
  padding: 0.3rem 0.45rem;
  color: var(--text-faint);
  font-size: 0.8rem;
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  transition:
    background     var(--dur-fast) var(--ease-out),
    color          var(--dur-fast) var(--ease-out),
    border-color   var(--dur-fast) var(--ease-out);
}

.btn-icon:hover {
  background: var(--surface-2);
  color: var(--text);
  border-color: var(--line-strong);
}

.btn-icon.danger:hover {
  background: var(--danger-soft);
  color: var(--danger);
  border-color: #fca5a5;
}

.btn-back {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: transparent;
  border: 0;
  padding: 0.2rem 0;
  color: var(--text-faint);
  font-size: 0.83rem;
  text-decoration: none;
  cursor: pointer;
  transition: color var(--dur-fast) var(--ease-out);
}

.btn-back:hover {
  color: var(--text-strong);
}