/* NKB Tech - Visual Subnet Calculator (/tools/subnet-calculator) */
.sc-page {
  background: var(--bg-alt);
  padding: 3rem 1.5rem 4rem;
}
.sc-container {
  max-width: 1040px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}
.sc-intro h1 {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.25;
}
.sc-intro p { color: var(--text-light); margin-top: 0.35rem; }
#subnet-calc { display: flex; flex-direction: column; gap: 1.5rem; }

/* Cards */
.sc-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-md);
  padding: 1.5rem;
}
.sc-card-title {
  font-family: var(--font-body);
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 1rem;
}
.sc-card-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-start;
  gap: 0.75rem;
  margin-bottom: 1rem;
}
.sc-card-head .sc-card-title { margin-bottom: 0.15rem; }
.sc-card-tools { display: flex; gap: 0.5rem; }
.sc-summary { font-size: 0.875rem; color: var(--text-light); }

/* Form */
.sc-form {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr) auto;
  gap: 1rem 1.25rem;
  align-items: end;
}
.sc-field { display: flex; flex-direction: column; gap: 0.4rem; min-width: 0; }
.sc-field label { font-size: 0.875rem; font-weight: 500; color: var(--text); }
.sc-field input,
.sc-field select {
  font: inherit;
  font-size: 0.95rem;
  height: 2.6rem;
  padding: 0 0.85rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background-color: var(--bg);
  color: var(--text);
  width: 100%;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.sc-field select {
  appearance: none;
  -webkit-appearance: none;
  padding-right: 2.25rem;
  cursor: pointer;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='none' stroke='%236b7280' stroke-width='1.5' d='M3 4.5l3 3 3-3'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.8rem center;
}
.sc-field input:focus,
.sc-field select:focus {
  outline: none;
  border-color: var(--primary-light);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.18);
}
.sc-form-actions { display: flex; gap: 0.75rem; }
.sc-options {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.75rem;
  margin-top: 1.1rem;
}
.sc-check {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--text);
  cursor: pointer;
}
.sc-check input { width: 1rem; height: 1rem; accent-color: var(--primary-light); cursor: pointer; }

/* Buttons */
.sc-btn {
  font: inherit;
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: 6px;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
}
.sc-btn-primary,
.sc-btn-muted {
  height: 2.6rem;
  min-width: 7.5rem;
  padding: 0 1.5rem;
  border: none;
  color: #fff;
}
.sc-btn-primary { background: var(--primary-light); }
.sc-btn-primary:hover { background: var(--primary); }
.sc-btn-muted { background: #6b7280; }
.sc-btn-muted:hover { background: #4b5563; }
.sc-btn-outline,
.sc-btn-sm {
  background: var(--bg);
  color: var(--text);
  border: 1px solid #cbd5e1;
}
.sc-btn-outline { padding: 0.4rem 0.85rem; font-size: 0.85rem; }
.sc-btn-outline:hover,
.sc-btn-sm:hover:not(:disabled) { border-color: var(--primary-light); color: var(--primary-light); }
.sc-btn-sm { padding: 0.3rem 0.75rem; font-size: 0.82rem; }
.sc-btn-sm:disabled { opacity: 0.4; cursor: not-allowed; }
.sc-btn-join { color: var(--text-light); }
.sc-btn:focus-visible {
  outline: 2px solid var(--primary-light);
  outline-offset: 2px;
}

/* Messages */
.sc-message { margin-top: 1rem; font-size: 0.875rem; }
.sc-message:empty { display: none; }
.sc-message-info,
.sc-message-warn,
.sc-message-error {
  padding: 0.6rem 0.9rem;
  border-radius: 6px;
  border-left: 4px solid;
}
.sc-message-info { background: var(--bg-blue-light); border-color: var(--primary-light); }
.sc-message-warn { background: rgba(249, 115, 22, 0.1); border-color: var(--accent); }
.sc-message-error { background: rgba(220, 38, 38, 0.08); border-color: #dc2626; }

/* Table */
.sc-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: 6px;
}
.sc-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  font-variant-numeric: tabular-nums;
}
.sc-table th,
.sc-table td {
  padding: 0.65rem 0.9rem;
  text-align: left;
  vertical-align: middle;
  border-bottom: 1px solid var(--border);
}
.sc-table tbody tr:last-child > * { border-bottom: none; }
.sc-table thead th {
  background: var(--bg-alt);
  font-weight: 600;
  font-size: 0.85rem;
  color: var(--text);
  white-space: nowrap;
}
.sc-table tbody tr:hover > * { background: var(--bg-blue-light); }
.sc-col-hosts { text-align: right !important; white-space: nowrap; }
.sc-col-actions { width: 1%; white-space: nowrap; }
.sc-actions { display: flex; gap: 0.4rem; justify-content: flex-end; }

/* CIDR cell with tree connectors. Lines are absolutely positioned inside the
   cell (offset by the cell's left padding) and span its full height so they
   join up across rows. */
.sc-cidr {
  position: relative;
  white-space: nowrap;
  font-weight: 500;
  color: var(--text);
}
.sc-tree-line,
.sc-tree-elbow {
  position: absolute;
  margin-left: 0.9rem; /* matches cell padding-left */
  pointer-events: none;
  border-color: #94a3b8;
}
/* │ : an ancestor level that still has a sibling further down */
.sc-tree-line {
  top: 0;
  bottom: 0;
  border-left: 1.5px solid #94a3b8;
}
/* └ : last child at this level */
.sc-tree-elbow {
  top: 0;
  height: 50%;
  width: 0.75rem;
  border-left: 1.5px solid #94a3b8;
  border-bottom: 1.5px solid #94a3b8;
}
/* ├ : more siblings below */
.sc-tree-elbow.sc-tree-mid {
  height: auto;
  bottom: 0;
  border-bottom: none;
}
.sc-tree-elbow.sc-tree-mid::after {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  width: 0.75rem;
  border-bottom: 1.5px solid #94a3b8;
}
.sc-row-parent > * { background: var(--bg-alt); }
.sc-row-parent .sc-cidr-text { font-weight: 600; }
.sc-row-parent .sc-range { color: var(--text-light); }
.sc-cidr-text {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.86rem;
}
.sc-range {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.86rem;
  color: var(--text);
  white-space: nowrap;
}
.sc-details {
  display: flex;
  flex-wrap: wrap;
  margin-top: 0.2rem;
  font-size: 0.78rem;
  color: var(--text-light);
  line-height: 1.5;
}
.sc-details { column-gap: 1rem; }
.sc-details span { white-space: nowrap; }
.sc-compact .sc-details { display: none; }
.sc-hosts-unit { color: var(--text-light); font-size: 0.82rem; margin-left: 0.2rem; }

.sc-table tr.sc-invalid .sc-cidr-text,
.sc-table tr.sc-invalid .sc-range { color: #b91c1c; }
.sc-flag {
  display: inline-block;
  margin-left: 0.5rem;
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 600;
  padding: 0.05rem 0.4rem;
  border-radius: 999px;
  background: rgba(220, 38, 38, 0.12);
  color: #b91c1c;
}

/* Help card */
.sc-help { color: var(--text); }
.sc-help h3 { font-size: 1rem; font-weight: 600; margin: 1.25rem 0 0.4rem; }
.sc-help ol { padding-left: 1.3rem; }
.sc-help li { margin-bottom: 0.35rem; }
.sc-help p,
.sc-help li { font-size: 0.92rem; color: var(--text); }
.sc-help code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.85em;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.05rem 0.3rem;
}

/* Dark theme */
[data-theme="dark"] .sc-page { background: var(--bg); }
[data-theme="dark"] .sc-card { background: var(--bg-alt); }
[data-theme="dark"] .sc-field input,
[data-theme="dark"] .sc-field select,
[data-theme="dark"] .sc-btn-outline,
[data-theme="dark"] .sc-btn-sm { background-color: var(--bg); border-color: var(--border); }
[data-theme="dark"] .sc-table thead th { background: var(--bg); }
[data-theme="dark"] .sc-table tr.sc-invalid .sc-cidr-text,
[data-theme="dark"] .sc-table tr.sc-invalid .sc-range,
[data-theme="dark"] .sc-flag { color: #fca5a5; }
[data-theme="dark"] .sc-tree-line,
[data-theme="dark"] .sc-tree-elbow,
[data-theme="dark"] .sc-tree-elbow::after { border-color: #475569; }

/* Responsive */
@media (max-width: 760px) {
  .sc-form { grid-template-columns: 1fr 1fr; }
  .sc-field-net { grid-column: 1 / -1; }
  .sc-form-actions { grid-column: 1 / -1; }
  .sc-form-actions .sc-btn { flex: 1; }
  .sc-intro h1 { font-size: 1.6rem; }
}
@media (max-width: 480px) {
  .sc-page { padding: 2rem 1rem 3rem; }
  .sc-card { padding: 1.1rem; }
  .sc-form { grid-template-columns: 1fr; }
}