:root {
    --bg: #0d0d0d;
    --surface: #141414;
    --border: #2a2a2a;
    --green: #00ff88;
    --cyan: #00cfff;
    --red: #ff4f4f;
    --gray: #888;
    --white: #e8e8e8;
    --dark-red: #1a0a0a;
}

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

body {
    background: var(--bg);
    color: var(--white);
    font-family: 'Courier New', monospace;
    min-height: 100vh;
    padding: 40px 20px;
}

#app {
    max-width: 860px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 28px;
}

header h1 { font-size: 2rem; letter-spacing: 0.1em; }
header h1 span { color: var(--green); }
header p { color: var(--gray); font-size: 13px; margin-top: 4px; }

#fila-entrada {
    display: flex;
    align-items: center;
    gap: 8px;
}

#ip-entrada {
    flex: 1;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 10px 14px;
    color: var(--white);
    font-family: 'Courier New', monospace;
    font-size: 14px;
    outline: none;
    transition: border-color 0.2s;
}

#ip-entrada:focus { border-color: var(--green); }
#ip-entrada::placeholder { color: var(--gray); } 

.slash { font-size: 1.4rem; color: var(--gray); }

#cidr-entrada {
    width: 70px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 10px 14px;
    color: var(--white);
    font-family: 'Courier New', monospace;
    font-size: 14px;
    outline: none;
    transition: border-color 0.2s;
}

#cidr-entrada:focus { border-color: var(--green); }

#btn-calcular {
    background: var(--green);
    border: none;
    border-radius: 6px;
    padding: 10px 18px;
    color: var(--bg);
    font-family: 'Courier New', monospace;
    font-size: 13px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: opacity 0.2s;
    white-space: nowrap;
}

#btn-calcular:hover { opacity: 0.85; }

#mensaje-error {
    background: var(--dark-red);
    border: 1px solid var(--red);
    border-radius: 6px;
    padding: 10px 14px;
    color: var(--red);
    font-size: 12px;
    margin-top: 8px;
}

#btns-rapidos {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: 12px;
}

.etiqueta-rapida { font-size: 11px; color: var(--gray); }

.btn-rapido {
    background: transparent;
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 4px 10px;
    color: var(--gray);
    font-family: 'Courier New', monospace;
    font-size: 11px;
    cursor: pointer;
    transition: border-color 0.15s, color 0.15s;
}
.btn-rapido:hover { border-color: var(--cyan); color: var(--cyan); }

#seccion-visual, #seccion-visual-rango {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

#seccion-visual h3, #seccion-visual-rango h3 {
  font-size: 12px;
  color: var(--gray);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

#tabla-resultados {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
}

.tarjeta-resultados {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.tarjeta-etiqueta {
  font-size: 11px;
  color: var(--gray);
  display: flex;
  align-items: center;
  gap: 6px;
}

.tarjeta-valores {
  font-size: 1.1rem;
  color: var(--white);
  letter-spacing: 0.05em;
}

.tarjeta-binaria, .tarjeta-subred {
  font-size: 10px;
  color: var(--gray);
  letter-spacing: 0.08em;
  word-break: break-all;
}

#binario-visual {
  display: flex;
  gap: 3px;
  flex-wrap: wrap;
}

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

.bit {
  width: 18px;
  height: 28px;
  border-radius: 3px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  font-weight: bold;
}

.bit.net  { background: #00cfff22; color: var(--cyan);  border: 1px solid #00cfff44; }
.bit.host { background: #00ff8822; color: var(--green); border: 1px solid #00ff8844; }

#binario-legend { display: flex; gap: 16px; }

.leg {
  font-size: 11px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.leg::before {
  content: '';
  width: 12px;
  height: 12px;
  border-radius: 2px;
  display: inline-block;
}
.leg.net::before  { background: #00cfff22; border: 1px solid #00cfff44; }
.leg.host::before { background: #00ff8822; border: 1px solid #00ff8844; }

#barra-de-rango {
  position: relative;
  height: 32px;
  background: #1e1e1e;
  border-radius: 6px;
  overflow: hidden;
  border: 1px solid var(--border);
}

#area-de-subred {
  position: absolute;
  top: 0; bottom: 0;
  left: 2px; right: 2px;
  background: linear-gradient(90deg, #00cfff22, #00ff8833);
  border-radius: 4px;
  border-left:  2px solid var(--cyan);
  border-right: 2px solid var(--red);
}

#etiquetas-de-rango {
  position: absolute;
  inset: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 8px;
  font-size: 10px;
}

#etiqueta-red, #etiqueta-difusion  { color: var(--cyan); }
#etiqueta-primer-host              { color: var(--green); }
#etiqueta-ultimo-host              { color: var(--red); }

.hidden { display: none !important; }

#fila-subredes {
  display: flex;
  gap: 8px;
  margin-top: 12px;
}

#num-subredes {
    width: 90px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 10px 14px;
    color: var(--white);
    font-family: 'Courier New', monospace;
    font-size: 14px;
    outline: none;
    transition: border-color 0.2s;
}
#num-subredes:focus { border-color: var(--cyan); }
#num-subredes::placeholder { color: var(--gray); }

#btn-subredes {
  background: var(--cyan);
  border: none;
  border-radius: 6px;
  padding: 10px 18px;
  color: #0d0d0d;
  font-family: 'Courier New', monospace;
  font-size: 13px;
  font-weight: bold;
  cursor: pointer;
  white-space: nowrap;
  transition: opacity 0.2s;
}
#btn-subredes:hover { opacity: 0.85; }

#tabla-subredes-wrap {
  display: flex;
  flex-direction: column;
  gap: 12px;
  animation: fadeIn 0.3s ease;
}

#tabla-subredes-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}

#tabla-subredes-header h3 {
  font-size: 12px;
  color: var(--gray);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

#tabla-subredes-meta {
  font-size: 11px;
  color: var(--gray);
}
#tabla-subredes-meta b { color: var(--cyan); }

#tabla-subredes-scroll {
  overflow-x: auto;
  border-radius: 8px;
  border: 1px solid var(--border);
}

#tabla-subredes {
  width: 100%;
  border-collapse: collapse;
  font-size: 12px;
}

#tabla-subredes thead tr {
  background: #1a1a1a;
  border-bottom: 1px solid var(--border);
}

#tabla-subredes th {
  padding: 10px 14px;
  text-align: left;
  color: var(--gray);
  font-weight: normal;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

#tabla-subredes tbody tr {
  border-bottom: 1px solid #1e1e1e;
  transition: background 0.15s;
}

#tabla-subredes tbody tr:hover { background: #1a1a1a; }
#tabla-subredes tbody tr:last-child { border-bottom: none; }
#tabla-subredes td { padding: 10px 14px; white-space: nowrap; }

.td-indice { color: var(--gray); }
.td-red    { color: var(--cyan); font-weight: bold; }
.td-mask   { color: var(--gray); }
.td-host   { color: var(--white); }
.td-bcast  { color: var(--red); }
.td-count  { color: var(--green); }

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

#seccion-salto-red {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

#seccion-salto-red h3 {
  font-size: 12px;
  color: var(--gray);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

#info-salto {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}