/* ============================================================
   Network Calculator — Styles
   Theme: Dark indigo (#6366F1)
   ============================================================ */

:root {
  --primary: #6366F1;
  --primary-hover: #818CF8;
  --primary-bg: rgba(99, 102, 241, 0.1);
  --secondary: #A5B4FC;
  --bg: #0F1219;
  --bg-card: #161B26;
  --bg-glass: rgba(22, 27, 38, 0.7);
  --bg-input: #111624;
  --border: rgba(99, 102, 241, 0.15);
  --border-hover: rgba(99, 102, 241, 0.3);
  --text: #E2E8F0;
  --text-muted: #94A3B8;
  --text-dim: #64748B;
  --green: #10B981;
  --red: #EF4444;
  --radius: 12px;
  --radius-sm: 8px;
  --font: 'Inter', system-ui, -apple-system, sans-serif;
  --transition: 200ms ease;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; -webkit-font-smoothing: antialiased; }
body { font-family: var(--font); background: var(--bg); color: var(--text); min-height: 100vh; line-height: 1.6; }
.app { max-width: 880px; margin: 0 auto; padding: 0 20px 60px; }

.header { padding: 24px 0 18px; border-bottom: 1px solid var(--border); margin-bottom: 24px; }
.logo-row { display: flex; align-items: center; gap: 12px; }
.logo-badge { width: 42px; height: 42px; display: flex; align-items: center; justify-content: center; background: var(--primary-bg); border-radius: var(--radius); border: 1px solid var(--border); }
h1 { font-size: 1.25rem; font-weight: 700; letter-spacing: -0.02em; }
.tagline { font-size: 0.78rem; color: var(--text-muted); }

.btn { display: inline-flex; align-items: center; gap: 6px; padding: 10px 18px; border: none; border-radius: var(--radius-sm); font-family: var(--font); font-size: 0.875rem; font-weight: 600; cursor: pointer; transition: all var(--transition); white-space: nowrap; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); box-shadow: 0 0 14px rgba(99,102,241,0.25); }
.btn-outline { background: var(--bg-card); color: var(--text-muted); border: 1px solid var(--border); }
.btn-outline:hover { border-color: var(--border-hover); color: var(--text); }

.input-section { margin-bottom: 24px; }
.input-row { display: flex; gap: 10px; }
#ipInput { flex: 1; padding: 11px 16px; background: var(--bg-input); border: 1px solid var(--border); border-radius: var(--radius); color: var(--text); font-family: var(--font); font-size: 0.95rem; outline: none; transition: border-color var(--transition); }
#ipInput:focus { border-color: var(--primary); }
#ipInput::placeholder { color: var(--text-dim); }
#cidrSelect { padding: 10px 12px; background: var(--bg-input); border: 1px solid var(--border); border-radius: var(--radius-sm); color: var(--text); font-family: var(--font); font-size: 0.85rem; outline: none; }

.results[hidden] { display: none; }
.results { animation: fadeUp 300ms ease; }
@keyframes fadeUp { from { opacity:0; transform:translateY(12px); } to { opacity:1; transform:translateY(0); } }

.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 12px; margin-bottom: 18px; }
.stat-card { background: var(--bg-glass); border: 1px solid var(--border); border-radius: var(--radius); padding: 14px; }
.stat-card .label { font-size: 0.68rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--text-dim); margin-bottom: 4px; }
.stat-card .value { font-size: 1.15rem; font-weight: 700; color: var(--secondary); font-family: monospace; word-break: break-all; }

.panel { background: var(--bg-glass); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px; margin-bottom: 16px; }
.panel-title { font-size: 0.9rem; font-weight: 600; margin-bottom: 12px; }

.detail-table { font-size: 0.82rem; }
.detail-row { display: flex; justify-content: space-between; padding: 7px 0; border-bottom: 1px solid rgba(99,102,241,0.06); }
.detail-row:last-child { border-bottom: none; }
.detail-key { color: var(--text-dim); }
.detail-val { font-family: monospace; font-weight: 600; text-align: right; }

.diagram { display: flex; flex-wrap: wrap; gap: 4px; }
.subnet-block { height: 28px; border-radius: 3px; display: flex; align-items: center; justify-content: center; font-size: 0.6rem; font-weight: 600; transition: all var(--transition); cursor: default; }
.subnet-block.net { background: rgba(99,102,241,0.2); border: 1px solid rgba(99,102,241,0.3); color: var(--secondary); }
.subnet-block.host { background: rgba(16,185,129,0.12); border: 1px solid rgba(16,185,129,0.2); color: var(--green); }
.subnet-block.bcast { background: rgba(239,68,68,0.12); border: 1px solid rgba(239,68,68,0.2); color: var(--red); }

.vlsm-input-row { display: flex; gap: 10px; margin-bottom: 12px; }
#vlsmInput { flex: 1; padding: 9px 14px; background: var(--bg-input); border: 1px solid var(--border); border-radius: var(--radius-sm); color: var(--text); font-family: var(--font); font-size: 0.85rem; outline: none; }
#vlsmInput:focus { border-color: var(--primary); }
#vlsmInput::placeholder { color: var(--text-dim); }

.vlsm-table { width: 100%; border-collapse: collapse; font-size: 0.8rem; margin-top: 8px; }
.vlsm-table th { text-align: left; padding: 8px; color: var(--text-dim); font-size: 0.7rem; text-transform: uppercase; border-bottom: 1px solid var(--border); }
.vlsm-table td { padding: 8px; border-bottom: 1px solid rgba(99,102,241,0.05); font-family: monospace; font-size: 0.78rem; }

.action-row { display: flex; gap: 10px; justify-content: center; margin-top: 8px; }
.empty-state { text-align: center; padding: 60px 20px; }
.empty-state[hidden] { display: none; }
.empty-ico { margin-bottom: 16px; }
.empty-state h2 { font-size: 1.1rem; margin-bottom: 6px; }
.empty-state p { color: var(--text-muted); font-size: 0.85rem; max-width: 400px; margin: 0 auto; }

@media (max-width: 640px) { .input-row { flex-direction: column; } .stats-grid { grid-template-columns: repeat(2, 1fr); } h1 { font-size: 1.1rem; } .vlsm-input-row { flex-direction: column; } }