/* Subnet calculator page styles. Built entirely on tokens.css custom
   properties — no hardcoded colors/fonts here (see tokens.json for the
   source of truth). Base reset/page/header/btn/badge/facts-grid rules
   below are shared verbatim with local-diag's own style.css (same
   product family); everything from "tab bar" onward is new to this
   tool. */

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--color-bg-base);
  color: var(--color-text-primary);
  font-family: var(--font-family-sans);
  font-size: var(--primitive-fontSize-base);
  line-height: 1.55;
}

[x-cloak] {
  display: none !important;
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition-duration: 0.01ms !important;
  }
}

.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;
}

.btn:focus-visible,
.field-input:focus-visible,
.tab:focus-visible,
.vlsm-table__hierarchy-cell--joinable:focus-visible,
details summary:focus-visible {
  outline: 2px solid var(--color-accent-active);
  outline-offset: 2px;
}

code, .mono {
  font-family: var(--font-family-mono);
}

.page {
  max-width: 900px;
  margin: 0 auto;
  padding: var(--primitive-spacing-8) var(--primitive-spacing-5) var(--primitive-spacing-20);
}

/* VLSM's table gets genuinely wide once a block has been divided a few
   times (5 columns + a hierarchy rail) — same "only as wide as the
   current view actually needs" instinct as local-diag's page--wide. */
.page--wide {
  max-width: 1120px;
}

html.pathlens-embedded .page,
html.pathlens-embedded .page--wide {
  width: 100%;
  max-width: none;
}

/* ---------------------------------------------------------------- header */

.page-header {
  margin-bottom: var(--primitive-spacing-8);
}

.page-header__eyebrow {
  font-family: var(--font-family-mono);
  font-size: var(--primitive-fontSize-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-accent-active-bright);
  margin-bottom: var(--primitive-spacing-2);
}

.page-header h1 {
  font-size: var(--primitive-fontSize-2xl);
  font-weight: 600;
  margin: 0 0 var(--primitive-spacing-2);
  letter-spacing: -0.01em;
}

.page-header p {
  color: var(--color-text-secondary);
  margin: 0;
  max-width: 62ch;
}

/* -------------------------------------------------------------- tab bar */

.tab-bar {
  display: flex;
  gap: var(--primitive-spacing-2);
  border-bottom: 1px solid var(--tab-bar-border);
  margin-bottom: var(--primitive-spacing-6);
}

.tab {
  appearance: none;
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  font-family: var(--font-family-sans);
  font-size: var(--tab-bar-font-size);
  font-weight: 600;
  color: var(--tab-bar-fg-inactive);
  padding: var(--tab-bar-padding-y) var(--tab-bar-padding-x);
  margin-bottom: -1px; /* sits on top of .tab-bar's own border */
  transition: color var(--primitive-duration-fast), border-color var(--primitive-duration-fast);
}

.tab:hover {
  color: var(--tab-bar-fg-active);
}

.tab--active {
  color: var(--tab-bar-fg-active);
  border-bottom-color: var(--tab-bar-indicator);
}

/* -------------------------------------------------------------- inputs */

.calc-input-row {
  display: flex;
  gap: var(--primitive-spacing-3);
  align-items: flex-start;
  margin-bottom: var(--primitive-spacing-6);
  flex-wrap: wrap;
}

.calc-input-row .field-input {
  flex: 1 1 260px;
  font-family: var(--font-family-mono);
}

.field-input {
  width: 100%;
  background: var(--textarea-bg);
  color: var(--textarea-fg);
  font-family: var(--font-family-sans);
  font-size: var(--primitive-fontSize-sm);
  border: 1px solid var(--textarea-border);
  border-radius: var(--primitive-radius-default);
  padding: var(--primitive-spacing-3) var(--primitive-spacing-3);
  min-height: 44px;
}

.field-input:focus-visible {
  border-color: var(--textarea-border-focus);
}

.field-hint {
  color: var(--color-text-muted);
  font-size: var(--primitive-fontSize-xs);
  margin-top: calc(-1 * var(--primitive-spacing-4));
  margin-bottom: var(--primitive-spacing-6);
}

/* ----------------------------------------------------------------- btn */

.btn {
  font-family: var(--font-family-sans);
  font-size: var(--primitive-fontSize-sm);
  font-weight: 600;
  border-radius: var(--primitive-radius-default);
  padding: var(--primitive-spacing-2) var(--primitive-spacing-4);
  min-height: 44px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--primitive-duration-fast);
  white-space: nowrap;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--color-accent-active);
  color: var(--primitive-color-graphite-950);
}

.btn-primary:hover:not(:disabled) {
  background: var(--color-accent-active-bright);
}

.btn-secondary {
  background: transparent;
  color: var(--color-text-secondary);
  border-color: var(--color-border-default);
}

.btn-secondary:hover:not(:disabled) {
  border-color: var(--color-border-strong);
  color: var(--color-text-primary);
}

.btn-small {
  font-size: var(--primitive-fontSize-xs);
  padding: var(--primitive-spacing-1) var(--primitive-spacing-3);
  min-height: 32px;
}

.link-button {
  background: none;
  border: none;
  color: var(--color-accent-info-bright);
  font-family: var(--font-family-sans);
  font-size: var(--primitive-fontSize-sm);
  cursor: pointer;
  padding: 0;
}

.link-button:hover {
  text-decoration: underline;
}

/* -------------------------------------------------------------- badges */

.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--primitive-spacing-1);
  font-family: var(--badge-font);
  font-size: var(--badge-font-size);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: var(--badge-padding-y) var(--badge-padding-x);
  border-radius: var(--badge-radius);
  border: 1px solid transparent;
  background: var(--badge-bg-neutral);
  color: var(--badge-fg-neutral);
}

.badge--info {
  background: var(--badge-bg-info);
  color: var(--badge-fg-info);
  border-color: var(--badge-border-info);
}

.badge--warning {
  background: var(--badge-bg-warning);
  color: var(--badge-fg-warning);
  border-color: var(--badge-border-warning);
}

.error-box {
  background: var(--color-accent-danger-bg);
  border: 1px solid var(--color-accent-danger-border);
  color: var(--color-accent-danger-bright);
  border-radius: var(--primitive-radius-default);
  padding: var(--primitive-spacing-3);
  font-size: var(--primitive-fontSize-sm);
  margin-bottom: var(--primitive-spacing-6);
}

/* ---------------------------------------------------------- result card */

.result-card {
  background: var(--step-card-bg);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--primitive-radius-lg);
  padding: var(--step-card-padding);
  margin-bottom: var(--primitive-spacing-6);
}

.result-card__title {
  font-size: var(--primitive-fontSize-sm);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  margin: 0 0 var(--primitive-spacing-4);
}

/* ----------------------------------------------------------- bit map */

.quick-bit-legend {
  display: flex;
  flex-wrap: wrap;
  gap: var(--primitive-spacing-5);
  font-size: var(--primitive-fontSize-xs);
  color: var(--bit-strip-label-fg);
  margin-bottom: var(--primitive-spacing-5);
}

.bit-strip__legend-item {
  display: flex;
  align-items: center;
  gap: var(--primitive-spacing-2);
}

.bit-strip__legend-swatch {
  width: 0.75rem;
  height: 0.75rem;
  border-radius: var(--bit-strip-radius);
  display: inline-block;
}

.bit-strip__legend-swatch--network {
  background: var(--bit-strip-network-bg);
}

.bit-strip__legend-swatch--host {
  background: var(--bit-strip-host-bg);
}

.quick-bit-legend__fill {
  display: inline-flex;
  align-items: center;
  gap: var(--primitive-spacing-2);
}

.quick-bit-table {
  display: grid;
  gap: var(--primitive-spacing-2);
}

.quick-bit-table__divider {
  height: 1px;
  background: var(--color-border-default);
  margin: var(--primitive-spacing-2) 0;
}

.quick-bit-row {
  display: grid;
  grid-template-columns: 5.25rem minmax(0, 13rem) minmax(0, 1fr);
  gap: var(--primitive-spacing-3);
  align-items: center;
  min-height: 1.75rem;
}

.quick-bit-row__label,
.quick-host-summary__label {
  color: var(--facts-grid-label-fg);
  font-family: var(--facts-grid-label-font);
  font-size: var(--facts-grid-label-font-size);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.quick-bit-row__value,
.quick-host-summary__value {
  color: var(--facts-grid-value-fg);
  font-family: var(--facts-grid-value-font);
  font-size: var(--facts-grid-value-font-size);
  white-space: nowrap;
}

.quick-bit-row__value {
  min-width: 0;
}

.quick-bit-clusters {
  display: flex;
  gap: var(--primitive-spacing-2);
  justify-self: end;
  min-width: 0;
}

.quick-bit-cluster {
  display: flex;
  gap: 2px;
}

.quick-bit-cell {
  width: 0.875rem;
  height: 0.875rem;
  display: inline-block;
  border: 1px solid currentColor;
  border-radius: 3px;
}

.quick-bit-cell--network {
  color: var(--bit-strip-network-bg);
}

.quick-bit-cell--host {
  color: var(--bit-strip-host-bg);
}

.quick-bit-cell--set {
  background: currentColor;
}

.quick-bit-cell--clear {
  background: transparent;
}

.quick-bit-cell--sample-filled {
  color: var(--bit-strip-network-bg);
  background: currentColor;
}

.quick-bit-cell--sample-hollow {
  color: var(--bit-strip-host-bg);
}

.quick-inline-callout {
  display: inline-flex;
  align-items: baseline;
  gap: var(--primitive-spacing-2);
  margin-left: var(--primitive-spacing-2);
  padding: 2px var(--primitive-spacing-2);
  border: 1px solid currentColor;
  border-radius: var(--primitive-radius-default);
  font-family: var(--font-family-sans);
  font-size: var(--primitive-fontSize-xs);
  font-weight: 500;
  white-space: nowrap;
}

.quick-inline-callout__detail {
  color: var(--color-text-secondary);
  font-family: var(--font-family-mono);
  font-size: 0.6875rem;
}

.quick-inline-callout--class {
  color: var(--color-accent-active-bright);
  background: var(--color-accent-active-bg);
}

.quick-inline-callout--class .quick-inline-callout__detail {
  display: none;
}

.quick-inline-callout--special {
  color: var(--badge-fg-info);
  background: var(--badge-bg-info);
}

.quick-host-summary {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--primitive-spacing-3);
  margin-top: var(--primitive-spacing-5);
  padding-top: var(--primitive-spacing-4);
  border-top: 1px solid var(--color-border-subtle);
}

.quick-host-summary .quick-inline-callout {
  margin-left: 0;
}

.quick-bit-explainer {
  border-top: 1px solid var(--color-border-subtle);
  color: var(--color-text-secondary);
  font-size: var(--primitive-fontSize-sm);
  margin-top: var(--primitive-spacing-5);
  padding-top: var(--primitive-spacing-4);
}

.quick-bit-explainer h3 {
  color: var(--color-text-primary);
  font-size: var(--primitive-fontSize-sm);
  margin: 0 0 var(--primitive-spacing-2);
}

.quick-bit-explainer p {
  margin: 0;
  max-width: 78ch;
}

.quick-bit-explainer p + p {
  margin-top: var(--primitive-spacing-2);
}

@media (max-width: 780px) {
  .quick-bit-row {
    grid-template-columns: 5.25rem 1fr;
  }

  .quick-bit-clusters {
    grid-column: 1 / -1;
    justify-self: start;
  }
}

@media (max-width: 480px) {
  .quick-bit-row {
    grid-template-columns: 1fr;
    gap: var(--primitive-spacing-1);
  }

  .quick-bit-row__value {
    white-space: normal;
  }

  .quick-bit-clusters {
    /* At this width even the shrunk 0.6875rem cells (below) don't fit
       4 clusters of 8 on one line — 320-375px viewports, verified
       directly, genuinely overflowed past the card edge with content
       silently clipped (no scrollbar, nothing indicating more was
       there) rather than just visually cramped. Wrapping onto a second
       line keeps every bit fully visible and legible instead. */
    gap: 5px;
    flex-wrap: wrap;
    row-gap: var(--primitive-spacing-1);
  }

  .quick-bit-cluster {
    gap: 1px;
  }

  .quick-bit-cell {
    width: 0.6875rem;
    height: 0.6875rem;
  }

  .quick-inline-callout__detail {
    display: none;
  }
}

/* --------------------------------------------------------- facts grid */

.facts-grid {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--facts-grid-row-gap) var(--facts-grid-column-gap);
}

.facts-grid__label {
  color: var(--facts-grid-label-fg);
  font-family: var(--facts-grid-label-font);
  font-size: var(--facts-grid-label-font-size);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.facts-grid__value {
  color: var(--facts-grid-value-fg);
  font-family: var(--facts-grid-value-font);
  font-size: var(--facts-grid-value-font-size);
  word-break: break-word;
}

@media (max-width: 480px) {
  .facts-grid {
    grid-template-columns: 1fr;
    gap: 0 var(--facts-grid-row-gap);
  }

  .facts-grid__value {
    margin-bottom: var(--primitive-spacing-2);
  }
}

/* ----------------------------------------------------- special-use callout */

.special-use-callout {
  display: flex;
  align-items: flex-start;
  gap: var(--primitive-spacing-3);
  background: var(--badge-bg-info);
  border: 1px solid var(--badge-border-info);
  border-radius: var(--primitive-radius-default);
  padding: var(--primitive-spacing-3) var(--primitive-spacing-4);
  margin-top: var(--primitive-spacing-4);
  font-size: var(--primitive-fontSize-sm);
}

.special-use-callout__icon {
  color: var(--badge-fg-info);
  flex-shrink: 0;
  margin-top: 2px;
}

.special-use-callout__label {
  color: var(--badge-fg-info);
  font-weight: 600;
}

.special-use-callout__cidr {
  font-family: var(--font-family-mono);
  color: var(--color-text-secondary);
  font-size: var(--primitive-fontSize-xs);
}

.historic-class-note {
  color: var(--color-text-muted);
  font-size: var(--primitive-fontSize-xs);
  margin-top: var(--primitive-spacing-2);
}

/* -------------------------------------------------------------- VLSM tab */

.vlsm-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--primitive-spacing-4);
}

.vlsm-toolbar__summary {
  color: var(--color-text-secondary);
  font-size: var(--primitive-fontSize-sm);
}

/* Scoped horizontal scroll for the table specifically — verified
   directly at 320/375px that without this, the table (6 columns,
   several with wide monospace content) pushed the WHOLE PAGE wider
   than the viewport rather than just scrolling itself. */
.vlsm-table-scroll {
  overflow-x: auto;
  margin-bottom: var(--primitive-spacing-4);
}

.vlsm-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--primitive-fontSize-sm);
}

.vlsm-table th {
  text-align: left;
  color: var(--facts-grid-label-fg);
  font-family: var(--facts-grid-label-font);
  font-size: var(--facts-grid-label-font-size);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  font-weight: 400;
  padding: var(--primitive-spacing-2) var(--primitive-spacing-3);
  border-bottom: 1px solid var(--color-border-default);
}

.vlsm-table td {
  padding: var(--primitive-spacing-3);
  border-bottom: 1px solid var(--vlsm-table-row-border);
  font-family: var(--font-family-mono);
  vertical-align: middle;
}

.vlsm-table tbody tr:hover {
  background: var(--vlsm-table-row-bg-hover);
}

.vlsm-table__subnet {
  font-weight: 600;
  color: var(--color-text-primary);
}

/* The hierarchy rail — matches davidc.net's own visual pattern of a
   shaded bracket spanning two sibling rows that would recombine.
   rowspan="2" on the cell itself (set in index.html from the
   pre-computed vlsmRows getter) is what makes one cell visually cover
   both rows; a lone leaf with no joinable sibling still gets a
   rowspan="1" cell here so the column's width stays constant whether
   or not anything in it is currently clickable. */
.vlsm-table__hierarchy-col {
  width: 2.5rem;
}

.vlsm-table__hierarchy-cell {
  padding: 0;
  border-bottom: 1px solid var(--vlsm-table-row-border);
}

.vlsm-table__hierarchy-cell--joinable {
  background: var(--vlsm-table-hierarchy-bg);
  border: 1px solid var(--vlsm-table-hierarchy-border);
  border-radius: var(--primitive-radius-sm);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--primitive-duration-fast);
}

.vlsm-table__hierarchy-cell--joinable:hover {
  background: var(--vlsm-table-hierarchy-bg-hover);
}

.vlsm-table__hierarchy-icon {
  color: var(--vlsm-table-hierarchy-fg);
  transition: color var(--primitive-duration-fast);
}

.vlsm-table__hierarchy-cell--joinable:hover .vlsm-table__hierarchy-icon {
  color: var(--bit-strip-network-fg);
}

.vlsm-table__hierarchy-cell--joinable:hover::after {
  color: var(--bit-strip-network-fg);
}

.vlsm-export {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: var(--primitive-spacing-3);
  margin-top: var(--primitive-spacing-5);
}

.vlsm-export .btn {
  display: inline-flex;
  align-items: center;
  gap: var(--primitive-spacing-2);
}

.vlsm-export__status {
  color: var(--color-text-secondary);
  font-size: var(--primitive-fontSize-sm);
}