.feature-page {
  height: 100%;
  overflow: auto;
  padding: clamp(var(--space-lg), 3vw, var(--space-3xl));
  background:
    radial-gradient(circle at 92% -8%, var(--color-accent-soft) 0, transparent 28%),
    var(--color-background-primary);
  user-select: text;
  scrollbar-gutter: stable;
  animation: page-in var(--motion-normal) both;
}

.chat-page,
.workspace-view {
  animation: page-in var(--motion-normal) both;
}

.feature-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-lg);
  margin: 0 auto var(--space-2xl);
  max-width: 1180px;
}

.feature-header h1 { font-size: clamp(var(--font-size-2xl), 2.3vw, 30px); line-height: 1.15; letter-spacing: -.025em; }
.feature-header p { max-width: 680px; margin-top: var(--space-sm); color: var(--color-text-secondary); }
.feature-actions, .inline-actions { display: flex; align-items: center; flex-wrap: wrap; gap: var(--space-sm); }
.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: var(--space-lg); max-width: 1180px; margin-inline: auto; }
.feature-page > .panel { max-width: 1180px; margin-inline: auto; }
.split-view { display: grid; grid-template-columns: minmax(260px, .8fr) minmax(360px, 1.7fr); gap: var(--space-lg); min-height: 0; }

.panel, .item-card {
  border: 1px solid var(--color-border-default);
  border-radius: var(--radius-lg);
  background: var(--color-surface-primary);
  box-shadow: var(--shadow-sm);
}

.panel { padding: clamp(var(--space-lg), 2.2vw, var(--space-2xl)); }
.item-card {
  padding: var(--space-lg);
  transition: border-color var(--motion-fast), box-shadow var(--motion-fast), transform var(--motion-fast), background-color var(--motion-fast);
}
.item-card:hover { border-color: var(--color-accent-secondary); box-shadow: var(--shadow-md); transform: translateY(-2px); }
.item-card.selected { border-color: var(--color-accent-primary); box-shadow: 0 0 0 3px var(--color-accent-soft), var(--shadow-md); }
.panel-title { margin-bottom: var(--space-md); font-size: var(--font-size-xl); }
.muted { color: var(--color-text-secondary); }
.subtle { color: var(--color-text-tertiary); font-size: var(--font-size-sm); }

.button-primary, .button-secondary, .button-danger, .icon-button {
  min-height: 34px;
  padding: 0 var(--space-md);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  font-weight: 600;
  line-height: 1;
  transition: background-color var(--motion-fast), border-color var(--motion-fast), color var(--motion-fast), box-shadow var(--motion-fast), transform var(--motion-fast);
}

.button-primary { background: var(--color-accent-primary); color: var(--color-text-inverse); box-shadow: 0 4px 12px color-mix(in srgb, var(--color-accent-primary) 24%, transparent); }
.button-primary:hover { background: var(--color-accent-primary-hover); transform: translateY(-1px); box-shadow: 0 7px 18px color-mix(in srgb, var(--color-accent-primary) 28%, transparent); }
.button-secondary { border-color: var(--color-border-default); background: var(--color-surface-primary); }
.button-secondary:hover, .icon-button:hover { border-color: var(--color-accent-secondary); background: var(--color-background-hover); color: var(--color-accent-primary); transform: translateY(-1px); }
.button-danger { background: var(--color-error-soft); color: var(--color-error); }
.button-danger:hover { transform: translateY(-1px); box-shadow: 0 5px 14px color-mix(in srgb, var(--color-error) 18%, transparent); }
button:active:not(:disabled) { transform: translateY(0); }
button:disabled { cursor: not-allowed; opacity: .55; box-shadow: none; transform: none; }

.field { display: grid; gap: var(--space-xs); }
.field label { color: var(--color-text-secondary); font-size: var(--font-size-sm); font-weight: 600; }
.input, .select, .textarea {
  width: 100%;
  border: 1px solid var(--color-border-default);
  border-radius: var(--radius-md);
  outline: none;
  background: var(--color-background-primary);
  color: var(--color-text-primary);
  transition: border-color var(--motion-fast), box-shadow var(--motion-fast), background-color var(--motion-fast);
}
.input, .select { height: 38px; padding: 0 var(--space-md); }
.textarea { min-height: 100px; padding: var(--space-md); resize: vertical; }
.input:hover, .select:hover, .textarea:hover { border-color: var(--color-text-tertiary); }
.input:focus, .select:focus, .textarea:focus { border-color: var(--color-border-focus); box-shadow: 0 0 0 3px var(--color-accent-soft); background: var(--color-surface-primary); }
.form-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: var(--space-md); }

input[type='checkbox'], input[type='radio'] {
  appearance: none;
  display: inline-grid;
  place-content: center;
  width: 18px;
  height: 18px;
  flex: 0 0 18px;
  border: 1px solid var(--color-border-default);
  background: var(--color-background-primary);
  transition: border-color var(--motion-fast), background-color var(--motion-fast), box-shadow var(--motion-fast);
}
input[type='checkbox'] { border-radius: 5px; }
input[type='radio'] { border-radius: 50%; }
input[type='checkbox']::before, input[type='radio']::before { content: ''; width: 10px; height: 10px; transform: scale(0); transition: transform var(--motion-fast); }
input[type='checkbox']::before { clip-path: polygon(14% 44%, 0 59%, 39% 96%, 100% 20%, 84% 7%, 37% 68%); background: var(--color-text-inverse); }
input[type='radio']::before { border-radius: 50%; background: var(--color-text-inverse); }
input[type='checkbox']:hover, input[type='radio']:hover { border-color: var(--color-accent-primary); }
input[type='checkbox']:checked, input[type='radio']:checked { border-color: var(--color-accent-primary); background: var(--color-accent-primary); }
input[type='checkbox']:checked::before, input[type='radio']:checked::before { transform: scale(1); }
input[type='checkbox']:disabled, input[type='radio']:disabled { cursor: not-allowed; opacity: .55; }

input[type='range'] { appearance: none; height: 20px; background: transparent; cursor: pointer; }
input[type='range']::-webkit-slider-runnable-track { height: 5px; border-radius: var(--radius-full); background: var(--color-background-tertiary); }
input[type='range']::-webkit-slider-thumb { appearance: none; width: 16px; height: 16px; margin-top: -5.5px; border: 2px solid var(--color-surface-primary); border-radius: 50%; background: var(--color-accent-primary); box-shadow: 0 1px 4px color-mix(in srgb, var(--color-text-primary) 24%, transparent); }

progress { appearance: none; width: 100%; height: 8px; overflow: hidden; border: 0; border-radius: var(--radius-full); background: var(--color-background-tertiary); }
progress::-webkit-progress-bar { border-radius: var(--radius-full); background: var(--color-background-tertiary); }
progress::-webkit-progress-value { border-radius: var(--radius-full); background: linear-gradient(90deg, var(--color-accent-primary), var(--color-accent-secondary)); }
progress:not([value]) { background: linear-gradient(90deg, var(--color-background-tertiary) 25%, var(--color-accent-secondary) 50%, var(--color-background-tertiary) 75%); background-size: 200% 100%; animation: progress-pulse 1.2s linear infinite; }

.ui-disclosure { padding: var(--space-md); border: 1px solid var(--color-border-default); border-radius: var(--radius-md); background: var(--color-background-secondary); }
.ui-disclosure > summary { display: flex; align-items: center; justify-content: space-between; gap: var(--space-sm); list-style: none; color: var(--color-text-secondary); font-weight: 600; cursor: pointer; }
.ui-disclosure > summary::-webkit-details-marker { display: none; }
.ui-disclosure > summary::after { content: ''; width: 8px; height: 8px; flex: 0 0 auto; border-right: 2px solid currentColor; border-bottom: 2px solid currentColor; transform: rotate(45deg); transition: transform var(--motion-fast); }
.ui-disclosure[open] > summary::after { transform: rotate(225deg); }
.ui-disclosure[open] > summary { margin-bottom: var(--space-md); color: var(--color-text-primary); }
.ui-disclosure > :not(summary) + :not(summary) { margin-top: var(--space-sm); }

.badge {
  display: inline-flex;
  align-items: center;
  min-height: 22px;
  padding: 0 var(--space-sm);
  border-radius: var(--radius-full);
  background: var(--color-background-tertiary);
  color: var(--color-text-secondary);
  font-size: var(--font-size-xs);
  font-weight: 600;
  letter-spacing: .01em;
}
.badge.success { background: var(--color-success-soft); color: var(--color-success); }
.badge.warning { background: var(--color-warning-soft); color: var(--color-warning); }
.badge.error { background: var(--color-error-soft); color: var(--color-error); }
.badge.info { background: var(--color-info-soft); color: var(--color-info); }
.tag-list { display: flex; flex-wrap: wrap; gap: var(--space-xs); }

.empty-state { display: grid; place-items: center; min-height: 220px; padding: var(--space-3xl); border: 1px dashed var(--color-border-default); border-radius: var(--radius-xl); background: color-mix(in srgb, var(--color-background-secondary) 74%, transparent); text-align: center; color: var(--color-text-secondary); }
.empty-state strong { display: block; margin-bottom: var(--space-xs); color: var(--color-text-primary); font-size: var(--font-size-xl); }
.error-banner, .notice-banner { border: 1px solid transparent; animation: notice-in var(--motion-normal) both; }
.error-banner { margin-bottom: var(--space-lg); padding: var(--space-md) var(--space-lg); border-color: color-mix(in srgb, var(--color-error) 22%, transparent); border-radius: var(--radius-md); background: var(--color-error-soft); color: var(--color-error); }
.notice-banner { margin-bottom: var(--space-lg); padding: var(--space-md) var(--space-lg); border-color: color-mix(in srgb, var(--color-info) 22%, transparent); border-radius: var(--radius-md); background: var(--color-info-soft); color: var(--color-info); }

.sidebar-panel { padding: var(--space-md); }
.sidebar-panel .input, .sidebar-panel .select { margin-bottom: var(--space-sm); }
.sidebar-list { display: grid; gap: var(--space-xs); }
.sidebar-list-item { padding: 9px var(--space-sm); border: 1px solid transparent; border-radius: var(--radius-md); cursor: pointer; transition: color var(--motion-fast), background-color var(--motion-fast), border-color var(--motion-fast), transform var(--motion-fast); }
.sidebar-list-item:hover { background: var(--color-background-hover); transform: translateX(2px); }
.sidebar-list-item.active { border-color: color-mix(in srgb, var(--color-accent-primary) 18%, transparent); background: var(--color-accent-soft); color: var(--color-accent-primary); }

.modal-backdrop { position: fixed; inset: 0; z-index: var(--z-modal); display: grid; place-items: center; padding: var(--space-xl); background: var(--color-background-overlay); animation: backdrop-in var(--motion-fast) both; }
.modal { width: min(560px, 100%); max-height: 85vh; overflow: auto; padding: var(--space-2xl); border: 1px solid var(--color-border-default); border-radius: var(--radius-xl); background: var(--color-surface-elevated); box-shadow: var(--shadow-xl); animation: modal-in var(--motion-normal) both; }
.modal h2 { margin-bottom: var(--space-lg); }
.modal form { display: grid; gap: var(--space-md); }

.settings-nav { display: flex; flex-wrap: wrap; gap: var(--space-xs); margin-bottom: var(--space-xl); padding: var(--space-xs); border: 1px solid var(--color-border-default); border-radius: var(--radius-lg); background: var(--color-background-secondary); }
.settings-nav button { padding: 8px var(--space-md); border-radius: var(--radius-md); color: var(--color-text-secondary); transition: color var(--motion-fast), background-color var(--motion-fast), box-shadow var(--motion-fast); }
.settings-nav button:hover { color: var(--color-text-primary); background: var(--color-background-hover); }
.settings-nav button.active { background: var(--color-surface-primary); color: var(--color-accent-primary); box-shadow: var(--shadow-sm); }

@keyframes page-in {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

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

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

@keyframes modal-in {
  from { opacity: 0; transform: translateY(8px) scale(.985); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

@keyframes progress-pulse { from { background-position: 100% 0; } to { background-position: -100% 0; } }

@media (max-width: 900px) {
  .feature-page { padding: var(--space-lg); }
  .split-view { grid-template-columns: 1fr; }
}


/* Shared select and disclosure chrome, including the expanded surface. */
:where(select:not([multiple]):not([size])), .select:not([multiple]):not([size]) {
  appearance: none;
  box-sizing: border-box;
  min-height: 38px;
  padding: 0 32px 0 12px;
  border: 1px solid var(--color-border-default);
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
  background-color: var(--color-surface-primary);
  background-image: linear-gradient(45deg, transparent 50%, currentColor 50%), linear-gradient(135deg, currentColor 50%, transparent 50%);
  background-position: calc(100% - 17px) 50%, calc(100% - 12px) 50%;
  background-size: 5px 5px;
  background-repeat: no-repeat;
  cursor: pointer;
}
.select { padding-right: 32px; }
:where(select option, select optgroup) { color: var(--color-text-primary); background: var(--color-surface-elevated); font: inherit; }
:where(select:disabled) { color: var(--color-text-disabled); cursor: not-allowed; }
@supports (appearance: base-select) {
  :where(select:not([multiple]):not([size])), .select:not([multiple]):not([size]), ::picker(select) { appearance: base-select; }
  :where(select:not([multiple]):not([size])), .select:not([multiple]):not([size]) { background-image: none; align-items: center; }
  select::picker-icon { color: var(--color-text-secondary); transition: transform var(--motion-fast); }
  select:open::picker-icon { transform: rotate(180deg); }
  ::picker(select) { color: var(--color-text-primary); background: var(--color-surface-elevated); border: 1px solid var(--color-border-default); border-radius: var(--radius-md); padding: 6px; box-shadow: var(--shadow-md); max-height: min(320px, 60vh); overflow: auto; }
  select option { padding: 8px 12px; min-height: 34px; border-radius: var(--radius-sm); }
  select option:is(:hover, :focus-visible) { background: var(--color-background-hover); }
  select option:checked { color: var(--color-accent-primary); background: var(--color-accent-soft); }
  select option::checkmark { color: var(--color-accent-primary); }
}
.ui-disclosure { border: 1px solid var(--color-border-default); border-radius: var(--radius-md); background: var(--color-surface-primary); overflow-wrap: anywhere; }
.ui-disclosure > summary { min-height: 38px; box-sizing: border-box; line-height: 1.5; border-radius: var(--radius-sm); padding: 6px 8px; }
.ui-disclosure > summary:hover { background: var(--color-background-hover); color: var(--color-accent-primary); }
.ui-disclosure[open] > summary { border-bottom: 1px solid var(--color-border-subtle); border-radius: var(--radius-sm) var(--radius-sm) 0 0; }