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

:root {
  --accent:           #0099d5;
  --accent-dim:       rgba(0,153,213,0.12);
  --accent-border:    rgba(0,153,213,0.30);

  --bg:               #0f0f10;
  --bg2:              rgba(255,255,255,0.04);

  --btn-bg:           rgba(255,255,255,0.07);
  --btn-hover-bg:     rgba(255,255,255,0.13);
  --btn-border:       rgba(255,255,255,0.10);
  --btn-border-hover: rgba(255,255,255,0.22);

  --bar-bg:           rgba(13,13,15,0.92);
  --bar-border:       rgba(255,255,255,0.07);

  --fg:               #f0f0f0;
  --fg-muted:         #888;
  --fg-subtle:        rgba(255,255,255,0.45);

  --net-color:        #ff6b6b;
  --bin-color:        rgba(255,255,255,0.35);

  --radius:           10px;
  --radius-lg:        14px;
  --blur:             blur(16px);
}

/* ── Light theme ── */
[data-theme="light"] {
  --accent:           #0077aa;
  --accent-dim:       rgba(0,119,170,0.12);
  --accent-border:    rgba(0,119,170,0.35);
  --bg:               #e8ebef;
  --bg2:              rgba(255,255,255,0.90);
  --btn-bg:           rgba(0,0,0,0.08);
  --btn-hover-bg:     rgba(0,0,0,0.14);
  --btn-border:       rgba(0,0,0,0.20);
  --btn-border-hover: rgba(0,0,0,0.38);
  --bar-bg:           rgba(255,255,255,0.97);
  --bar-border:       rgba(0,0,0,0.14);
  --fg:               #0a0c0f;
  --fg-muted:         #444;
  --fg-subtle:        rgba(0,0,0,0.60);
  --net-color:        #c0202a;
  --bin-color:        rgba(0,0,0,0.50);
}
[data-theme="light"] .result-card         { background: #fff; border-color: rgba(0,0,0,0.14); }
[data-theme="light"] table.rtable tr      { border-bottom-color: rgba(0,0,0,0.08); }
[data-theme="light"] td.divider           { background: rgba(0,0,0,0.08); }
[data-theme="light"] .form-card           { background: rgba(255,255,255,0.82); border-color: rgba(0,0,0,0.15); }
[data-theme="light"] .subnet-card         { background: #fff; border-color: rgba(0,0,0,0.14); }
[data-theme="light"] .history-item        { color: #333; }
[data-theme="light"] .badge-class  { background:rgba(0,119,170,0.12); color:#005f8a; border-color:rgba(0,119,170,0.30); }
[data-theme="light"] .badge-priv   { background:rgba(20,160,80,0.12); color:#0e7a3c; border-color:rgba(20,160,80,0.30); }
[data-theme="light"] .badge-pub    { background:rgba(190,100,0,0.12); color:#8a4800; border-color:rgba(190,100,0,0.30); }
[data-theme="light"] .badge-mc     { background:rgba(180,30,30,0.10); color:#9a1515; border-color:rgba(180,30,30,0.25); }

/* ── Body ── */
body {
  font-family: 'Open Sans', ui-sans-serif, system-ui, sans-serif;
  background: var(--bg);
  color: var(--fg);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* ── Topbar ── */
.topbar {
  height: 50px;
  display: flex;
  align-items: center;
  padding: 0 20px;
  gap: 16px;
  background: var(--bar-bg);
  border-bottom: 1px solid var(--bar-border);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  position: sticky;
  top: 0;
  z-index: 50;
}
.logo {
  font-family: 'JetBrains Mono', monospace;
  font-size: 16px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: -0.3px;
  flex-shrink: 0;
}
.logo span { color: rgba(255,255,255,0.22); }
[data-theme="light"] .logo span { color: rgba(0,0,0,0.22); }
.topbar-sep { width:1px; height:18px; background:var(--bar-border); flex-shrink:0; }
.topbar-desc { font-size:12.5px; color:var(--fg-subtle); white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }

/* ── Container ── */
.container { max-width:860px; margin:0 auto; padding:36px 20px 80px; }

/* ── Form card ── */
.form-card {
  background: var(--bg2);
  border: 1px solid var(--btn-border);
  border-radius: var(--radius-lg);
  padding: 24px 28px;
  margin-bottom: 28px;
}
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr auto;
  gap: 12px;
  align-items: end;
}
.field { display:flex; flex-direction:column; gap:6px; }
.field label {
  font-size: 11px;
  font-weight: 600;
  color: var(--fg-subtle);
  text-transform: uppercase;
  letter-spacing: 0.09em;
}
.field input {
  height: 36px;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  border-radius: var(--radius);
  color: var(--fg);
  font-family: 'JetBrains Mono', monospace;
  font-size: 13.5px;
  padding: 0 12px;
  outline: none;
  transition: border-color 0.15s, background 0.15s;
  width: 100%;
}
.field input::placeholder { color: var(--fg-muted); }
.field input:focus { border-color: var(--accent); background: rgba(0,153,213,0.06); }
.field input:hover:not(:focus) { border-color: var(--btn-border-hover); background: var(--btn-hover-bg); }

.calc-btn {
  height: 36px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-family: 'Open Sans', sans-serif;
  font-size: 13px;
  font-weight: 600;
  padding: 0 22px;
  cursor: pointer;
  white-space: nowrap;
  letter-spacing: 0.02em;
  transition: opacity 0.15s, transform 0.1s;
  flex-shrink: 0;
}
.calc-btn:hover { opacity: 0.85; }
.calc-btn:active { transform: scale(0.96); }

/* ── Results ── */
#results { display:none; }
#results.visible { display:block; }

.results-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}
.section-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--fg-subtle);
  text-transform: uppercase;
  letter-spacing: 0.09em;
}
.toggle-bin {
  height: 28px;
  padding: 0 12px;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  border-radius: var(--radius);
  color: var(--fg-muted);
  font-size: 11.5px;
  font-family: 'JetBrains Mono', monospace;
  cursor: pointer;
  letter-spacing: 0.04em;
  transition: all 0.15s;
}
.toggle-bin:hover { background:var(--btn-hover-bg); border-color:var(--btn-border-hover); color:var(--fg); }
.toggle-bin.active { border-color:var(--accent-border); color:var(--accent); background:var(--accent-dim); }

.result-card {
  background: var(--bg2);
  border: 1px solid var(--btn-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  animation: fadeIn 0.22s ease;
}
@keyframes fadeIn { from{opacity:0;transform:translateY(6px)} to{opacity:1;transform:none} }

/* ── Table ── */
table.rtable { width:100%; border-collapse:collapse; }
table.rtable tr { border-bottom:1px solid var(--bar-border); transition:background 0.1s; }
table.rtable tr:last-child { border-bottom:none; }
table.rtable tr.net-section td:first-child { border-left:2px solid var(--accent); }
table.rtable td { padding:10px 16px; font-family:'JetBrains Mono',monospace; font-size:13px; vertical-align:middle; }
td.lbl { width:120px; font-size:10.5px; text-transform:uppercase; letter-spacing:0.08em; color:var(--fg-muted); font-weight:400; white-space:nowrap; }
td.val { color:var(--fg); font-weight:500; position:relative; word-break:break-word; overflow-wrap:break-word; }

.copy-wrap {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  cursor: pointer;
  border-radius: 6px;
  padding: 2px 6px;
  margin: -2px -6px;
  transition: background 0.12s;
  user-select: none;
  white-space: nowrap;
}
.copy-wrap:hover { background:var(--btn-hover-bg); }
.copy-wrap:hover .ci { opacity:1; }
.ci { opacity:0; font-size:10px; color:var(--fg-muted); font-family:'Open Sans',sans-serif; transition:opacity 0.12s; }

/* ── Binary column — no wrap, nowrap on the whole cell ── */
td.bin-col {
  font-size: 11.5px;
  font-weight: 300;
  color: var(--bin-color);
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: background 0.1s;
  white-space: nowrap;   /* prevent line break */
}
td.bin-col:hover { background:var(--btn-bg); }
.bn { color:var(--net-color); }
td.meta { text-align:right; padding-right:18px; white-space:nowrap; }
td.divider { padding:0; height:1px; background:rgba(255,255,255,0.05); }

/* ── Badges ── */
.badge { display:inline-flex; align-items:center; font-size:10px; font-family:'Open Sans',sans-serif; font-weight:600; padding:3px 9px; border-radius:99px; letter-spacing:0.05em; text-transform:uppercase; }
.badge-class { background:rgba(0,153,213,0.12); color:#0099d5; border:1px solid rgba(0,153,213,0.25); }
.badge-priv  { background:rgba(34,197,120,0.10); color:#22c578; border:1px solid rgba(34,197,120,0.22); }
.badge-pub   { background:rgba(240,160,74,0.10); color:#f0a04a; border:1px solid rgba(240,160,74,0.22); }
.badge-mc    { background:rgba(255,107,107,0.10); color:#ff6b6b; border:1px solid rgba(255,107,107,0.22); }
.badges { display:flex; gap:5px; justify-content:flex-end; flex-wrap:wrap; }

/* ── Subnet section ── */
.subnet-section { margin-top:24px; animation:fadeIn 0.22s ease; }
.subnet-card { background:var(--bg2); border:1px solid var(--btn-border); border-radius:var(--radius-lg); padding:20px 24px; }
.subnet-bar { display:flex; height:26px; border-radius:8px; overflow:hidden; border:1px solid rgba(255,255,255,0.06); margin:12px 0 10px; }
.subnet-seg { height:100%; display:flex; align-items:center; justify-content:center; font-family:'JetBrains Mono',monospace; font-size:10px; font-weight:500; transition:opacity 0.15s; overflow:hidden; }
.subnet-seg:hover { opacity:0.8; }
.subnet-info { font-size:12.5px; color:rgba(255,255,255,0.35); font-family:'JetBrains Mono',monospace; }
.subnet-info span { color:var(--accent); }
[data-theme="light"] .subnet-info { color:rgba(0,0,0,0.45); }

/* ── History ── */
.history-section { margin-top:28px; }
.history-header { display:flex; align-items:center; justify-content:space-between; margin-bottom:10px; }
.clear-btn { background:none; border:none; color:var(--fg-muted); font-size:11.5px; cursor:pointer; font-family:'Open Sans',sans-serif; padding:0; transition:color 0.15s; }
.clear-btn:hover { color:var(--net-color); }
.history-list { display:flex; flex-wrap:wrap; gap:7px; }
.history-item { height:30px; padding:0 13px; background:var(--btn-bg); border:1px solid var(--btn-border); border-radius:var(--radius); font-family:'JetBrains Mono',monospace; font-size:12px; color:rgba(255,255,255,0.45); cursor:pointer; transition:all 0.15s; display:flex; align-items:center; white-space:nowrap; }
[data-theme="light"] .history-item { color: rgba(0,0,0,0.55); }
.history-item:hover { border-color:var(--accent-border); color:var(--accent); background:var(--accent-dim); }

/* ── Theme button ── */
.theme-btn {
  width:28px; height:28px;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  border-radius: 8px;
  color: var(--fg-subtle);
  font-size: 14px;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: all 0.15s;
  flex-shrink: 0;
}
.theme-btn:hover { background:var(--btn-hover-bg); border-color:var(--btn-border-hover); color:var(--fg); }
.theme-btn.active { background:var(--accent-dim); border-color:var(--accent-border); color:var(--accent); }

/* ── Cheat sheet ── */
#cheatTable td { padding:8px 16px; }
#cheatTable tr:hover { background:var(--btn-bg); }

/* ── Toast (copied notification) ── */
#toast {
  position: fixed;
  bottom: 28px;
  right: 28px;
  z-index: 9999;
  background: var(--accent);
  color: #fff;
  font-family: 'Open Sans', sans-serif;
  font-size: 13px;
  font-weight: 600;
  padding: 9px 18px;
  border-radius: 10px;
  pointer-events: none;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.18s ease, transform 0.18s ease;
  letter-spacing: 0.04em;
}
#toast.show {
  opacity: 1;
  transform: translateY(0);
}

/* ── Responsive ── */
@media (max-width:660px) {
  .topbar-desc { display:none; }
  .container { padding:24px 14px 60px; }
  .form-card { padding:18px; }
  .form-grid { grid-template-columns:1fr 1fr; gap:10px; }
  .form-grid .calc-btn-wrap { grid-column:1/-1; }
  .calc-btn { width:100%; }
  td.bin-col { display:none !important; }
  td.lbl { width:90px; font-size:9.5px; }
  td.val { font-size:12px; }
  td.meta { display:none; }
}