*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body, html {
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: sans-serif;
  font-size: 12px;
  background-color: var(--sz-color-window);
  color: var(--sz-color-window-text);
}

body {
  display: flex;
  flex-direction: column;
  height: 100vh;
  user-select: none;
}

/* ---- Menu bar ---- */

.menu-bar {
  display: flex;
  align-items: center;
  padding: 0;
  background: var(--sz-color-menu);
  border-bottom: 1px solid var(--sz-color-button-shadow);
  flex-shrink: 0;
}

.menu-item {
  position: relative;
  padding: 3px 8px;
  cursor: default;
  color: var(--sz-color-menu-text);
}

.menu-item:hover,
.menu-item.open {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
}

.menu-dropdown {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 200px;
  background: var(--sz-color-menu);
  border: 1px solid var(--sz-color-button-shadow);
  box-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
  z-index: 1000;
  padding: 2px 0;
}

.menu-item.open > .menu-dropdown {
  display: block;
}

.menu-entry {
  padding: 4px 24px 4px 8px;
  cursor: default;
  color: var(--sz-color-menu-text);
  white-space: nowrap;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.menu-entry:hover {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
}

.menu-entry .shortcut {
  margin-left: 24px;
  font-size: 10px;
  opacity: 0.7;
}

.menu-separator {
  height: 1px;
  background: var(--sz-color-button-shadow);
  margin: 2px 4px;
}

/* ---- Main area ---- */

.main-area {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 8px 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-height: 0;
}

/* ---- Sections (fieldsets) ---- */

.section {
  border: 1px solid var(--sz-color-button-shadow);
  padding: 8px 10px;
  flex-shrink: 0;
}

.section legend {
  font-weight: bold;
  padding: 0 4px;
  font-size: 11px;
  color: var(--sz-color-window-text);
}

/* ---- Input row ---- */

.input-row {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.input-row label {
  font-weight: bold;
  font-size: 11px;
}

.input-row .cidr-slash {
  font-weight: bold;
  font-size: 14px;
}

#ip-input {
  width: 130px;
  padding: 2px 4px;
  font-family: monospace;
  font-size: 12px;
}

#cidr-input {
  width: 48px;
  padding: 2px 4px;
  font-family: monospace;
  font-size: 12px;
}

#mask-input {
  width: 130px;
  padding: 2px 4px;
  font-family: monospace;
  font-size: 12px;
}

.input-invalid {
  outline: 2px solid #c44;
  outline-offset: -1px;
}

/* ---- Quick CIDR buttons ---- */

.quick-cidr {
  display: flex;
  gap: 3px;
  margin-top: 6px;
  flex-wrap: wrap;
}

.quick-cidr button {
  min-width: 32px;
  padding: 2px 4px;
  font-size: 10px;
  cursor: default;
  background: var(--sz-color-button-face);
  color: var(--sz-color-button-text);
  border: 1px solid var(--sz-color-button-shadow);
}

.quick-cidr button:hover {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
}

.quick-cidr button.active {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
  font-weight: bold;
}

/* ---- Results table ---- */

.results-table {
  width: 100%;
  border-collapse: collapse;
}

.results-table td {
  padding: 2px 8px 2px 0;
  vertical-align: top;
  font-size: 11px;
}

.results-table td:first-child {
  font-weight: bold;
  white-space: nowrap;
  width: 140px;
}

.results-table td:last-child {
  font-family: monospace;
  word-break: break-all;
}

/* ---- Bit view ---- */

.bit-view {
  display: grid;
  grid-template-columns: 8ch repeat(4, 1fr);
  gap: 3px 8px;
  font-family: monospace;
  font-size: 11px;
}

.bit-label {
  font-weight: bold;
  text-align: right;
  line-height: 18px;
  font-size: 10px;
}

.bit-group {
  display: flex;
  gap: 1px;
}

.bit {
  width: 18px;
  height: 18px;
  line-height: 18px;
  text-align: center;
  font-size: 10px;
  border: 1px solid var(--sz-color-button-shadow);
  background: var(--sz-color-button-face);
  user-select: none;
}

.bit.network-bit {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
}

.bit-mask.clickable {
  cursor: pointer;
}

.bit-mask.clickable:hover {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
  opacity: 0.8;
}

/* ---- Subnet division ---- */

.division-controls {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 6px;
}

.division-controls label {
  font-weight: bold;
  font-size: 11px;
}

.division-controls select {
  padding: 2px 4px;
  font-size: 11px;
}

.division-table-wrap {
  max-height: 200px;
  overflow-y: auto;
  border: 1px solid var(--sz-color-button-shadow);
}

.division-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 11px;
}

.division-table th {
  background: var(--sz-color-button-face);
  font-weight: bold;
  padding: 3px 6px;
  text-align: left;
  border-bottom: 1px solid var(--sz-color-button-shadow);
  position: sticky;
  top: 0;
}

.division-table td {
  padding: 2px 6px;
  font-family: monospace;
  white-space: nowrap;
}

.division-table tbody tr:nth-child(even) {
  background: rgba(0, 0, 0, 0.04);
}

.division-table tbody tr:hover {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
}

.division-error {
  padding: 6px;
  font-style: italic;
  color: var(--sz-color-gray-text);
  font-size: 11px;
}

/* ---- Status bar ---- */

.status-bar {
  display: flex;
  align-items: center;
  padding: 2px 8px;
  background: var(--sz-color-button-face);
  border-top: 1px solid var(--sz-color-button-shadow);
  font-size: 11px;
  color: var(--sz-color-button-text);
  flex-shrink: 0;
  gap: 16px;
}

.status-bar .status-section {
  white-space: nowrap;
}

.status-bar .status-section.inset {
  border: 1px inset var(--sz-color-button-shadow);
  padding: 1px 6px;
}

.status-invalid {
  color: #c44;
  font-weight: bold;
}

/* ---- Dialogs ---- */

.dialog-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.3);
  z-index: 2000;
  justify-content: center;
  align-items: center;
}

.dialog-overlay.visible {
  display: flex;
}

.dialog {
  background: var(--sz-color-button-face);
  border: 2px outset var(--sz-color-button-highlight);
  min-width: 300px;
  max-width: 450px;
  box-shadow: 3px 3px 8px rgba(0, 0, 0, 0.3);
}

.dialog-title {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
  padding: 4px 8px;
  font-weight: bold;
  font-size: 11px;
}

.dialog-body {
  padding: 12px;
  font-size: 11px;
}

.dialog-body p {
  margin-bottom: 8px;
}

.dialog-buttons {
  display: flex;
  justify-content: flex-end;
  gap: 6px;
  padding: 8px 12px;
}

.dialog-buttons button {
  min-width: 72px;
  padding: 3px 12px;
  font-size: 11px;
  cursor: default;
}