:root {
  --nka-black: #0a0a0a;
  --nka-white: #f8f8f8;
  --nka-gold: #c9a84c;
  --nka-gold-light: #e8c96a;
  --nka-gray: #1e1e1e;
  --nka-gray-mid: #2d2d2d;
  --nka-gray-light: #444;
  --nka-text: #e0e0e0;
  --nka-green: #2ecc71;
  --nka-red: #e74c3c;
  --nka-blue: #3498db;
  --radius: 8px;
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
}

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

body {
  background: var(--nka-black);
  color: var(--nka-text);
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  line-height: 1.6;
  min-height: 100vh;
}

a { color: var(--nka-gold); text-decoration: none; }
a:hover { color: var(--nka-gold-light); }

/* Nav */
nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  background: var(--nka-gray);
  border-bottom: 1px solid var(--nka-gray-mid);
}
.nav-brand { display: flex; align-items: center; gap: 0.75rem; }
.nav-brand img { height: 32px; }
.nav-brand .brand-text { font-size: 1.2rem; font-weight: 700; color: var(--nka-white); }
.nav-brand .brand-sub { font-size: 0.7rem; color: var(--nka-gold); letter-spacing: 0.08em; }
.nav-links { display: flex; gap: 1.5rem; align-items: center; font-size: 0.9rem; }
.btn {
  display: inline-flex; align-items: center; gap: 0.4rem;
  padding: 0.5rem 1.25rem; border-radius: var(--radius);
  font-size: 0.9rem; font-weight: 600; border: none; cursor: pointer;
  transition: all 0.15s;
}
.btn-primary { background: var(--nka-gold); color: var(--nka-black); }
.btn-primary:hover { background: var(--nka-gold-light); color: var(--nka-black); }
.btn-ghost { background: transparent; color: var(--nka-text); border: 1px solid var(--nka-gray-light); }
.btn-ghost:hover { border-color: var(--nka-gold); color: var(--nka-gold); }
.btn-danger { background: var(--nka-red); color: white; }

/* Cards */
.card {
  background: var(--nka-gray);
  border: 1px solid var(--nka-gray-mid);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

/* Hero */
.hero {
  text-align: center;
  padding: 4rem 2rem 2rem;
}
.hero h1 {
  font-size: 2.8rem; font-weight: 800;
  background: linear-gradient(135deg, var(--nka-white), var(--nka-gold));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 1rem;
}
.hero p { font-size: 1.1rem; color: #aaa; max-width: 520px; margin: 0 auto 2rem; }

/* Drop zone */
#drop-zone {
  border: 2px dashed var(--nka-gray-light);
  border-radius: var(--radius);
  padding: 3rem 2rem;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
  max-width: 560px;
  margin: 0 auto;
}
#drop-zone:hover, #drop-zone.dragover {
  border-color: var(--nka-gold);
  background: rgba(201,168,76,0.05);
}
#drop-zone .drop-icon { font-size: 2.5rem; margin-bottom: 0.75rem; }
#drop-zone p { color: #aaa; font-size: 0.9rem; margin-top: 0.5rem; }

/* Text area toggle */
.tab-bar {
  display: flex; gap: 0.5rem; max-width: 560px; margin: 1.5rem auto 0;
}
.tab-btn {
  flex: 1; padding: 0.5rem; border-radius: var(--radius) var(--radius) 0 0;
  background: var(--nka-gray-mid); border: none; color: #aaa; cursor: pointer;
  font-size: 0.85rem; font-weight: 600; transition: all 0.15s;
}
.tab-btn.active { background: var(--nka-gray); color: var(--nka-gold); }

#text-input-area {
  max-width: 560px; margin: 0 auto;
  background: var(--nka-gray);
  border: 1px solid var(--nka-gray-mid);
  border-top: none;
  border-radius: 0 0 var(--radius) var(--radius);
  padding: 1rem;
}
#text-input-area textarea {
  width: 100%; height: 120px; background: var(--nka-gray-mid);
  border: 1px solid var(--nka-gray-light); border-radius: 4px;
  color: var(--nka-text); padding: 0.75rem; font-family: monospace;
  resize: vertical;
}
#text-input-area textarea:focus { outline: none; border-color: var(--nka-gold); }

/* Progress + result */
#seal-progress { max-width: 560px; margin: 1.5rem auto 0; display: none; }
.progress-bar-track { background: var(--nka-gray-mid); border-radius: 99px; height: 6px; }
.progress-bar-fill { height: 6px; border-radius: 99px; background: var(--nka-gold); transition: width 0.4s; }
#seal-result { max-width: 560px; margin: 1.5rem auto 0; display: none; }
.result-success { border-color: var(--nka-green); }
.result-hash { font-family: monospace; font-size: 0.75rem; color: #aaa; word-break: break-all; }
.copy-btn { background: none; border: 1px solid var(--nka-gray-light); color: var(--nka-gold);
  padding: 0.25rem 0.75rem; border-radius: 4px; cursor: pointer; font-size: 0.8rem; margin-left: 0.5rem; }
.copy-btn:hover { border-color: var(--nka-gold); }

/* Verify page */
.verify-container { max-width: 600px; margin: 4rem auto; padding: 0 1rem; }
.verify-header { display: flex; align-items: center; gap: 1rem; margin-bottom: 1.5rem; }
.verify-icon { font-size: 2.5rem; }
.verify-status-valid { color: var(--nka-green); }
.verify-status-invalid { color: var(--nka-red); }
.proof-field { display: flex; flex-direction: column; gap: 0.25rem; margin-bottom: 1rem; }
.proof-label { font-size: 0.75rem; color: #888; text-transform: uppercase; letter-spacing: 0.06em; }
.proof-value { font-family: monospace; font-size: 0.85rem; color: var(--nka-text); word-break: break-all; }
.anchor-badge {
  display: inline-flex; align-items: center; gap: 0.4rem;
  padding: 0.25rem 0.75rem; border-radius: 99px; font-size: 0.8rem; font-weight: 600;
}
.anchor-confirmed { background: rgba(46,204,113,0.15); color: var(--nka-green); }
.anchor-pending { background: rgba(52,152,219,0.15); color: var(--nka-blue); }
.nka-footer {
  margin-top: 2rem; padding-top: 1.5rem; border-top: 1px solid var(--nka-gray-mid);
  text-align: center; font-size: 0.8rem; color: #666;
}
.nka-footer strong { color: var(--nka-gold); }

/* Dashboard */
.dashboard-container { max-width: 900px; margin: 2rem auto; padding: 0 1.5rem; }
.dashboard-grid { display: grid; grid-template-columns: 280px 1fr; gap: 1.5rem; }
.stat-row { display: flex; justify-content: space-between; align-items: center;
  padding: 0.75rem 0; border-bottom: 1px solid var(--nka-gray-mid); }
.stat-row:last-child { border-bottom: none; }
.stat-label { color: #888; font-size: 0.85rem; }
.stat-value { font-weight: 700; color: var(--nka-white); }
.usage-bar { background: var(--nka-gray-mid); border-radius: 99px; height: 8px; margin-top: 0.5rem; }
.usage-fill { height: 8px; border-radius: 99px; background: var(--nka-gold); transition: width 0.4s; }
.seal-table { width: 100%; border-collapse: collapse; font-size: 0.85rem; }
.seal-table th { text-align: left; color: #666; font-weight: 600; padding: 0.5rem 0.75rem;
  border-bottom: 1px solid var(--nka-gray-mid); }
.seal-table td { padding: 0.75rem; border-bottom: 1px solid var(--nka-gray-mid); }
.seal-table tr:hover td { background: rgba(255,255,255,0.02); }
.pill { display: inline-block; padding: 0.15rem 0.6rem; border-radius: 99px; font-size: 0.75rem; font-weight: 600; }
.pill-green { background: rgba(46,204,113,0.15); color: var(--nka-green); }
.pill-blue { background: rgba(52,152,219,0.15); color: var(--nka-blue); }
.pill-gold { background: rgba(201,168,76,0.15); color: var(--nka-gold); }

/* Auth pages */
.auth-container { max-width: 420px; margin: 5rem auto; padding: 0 1rem; }
.auth-container h1 { font-size: 1.8rem; margin-bottom: 1.5rem; text-align: center; }
.form-group { margin-bottom: 1.25rem; }
.form-group label { display: block; font-size: 0.85rem; color: #888; margin-bottom: 0.4rem; }
.form-group input {
  width: 100%; padding: 0.75rem 1rem;
  background: var(--nka-gray-mid); border: 1px solid var(--nka-gray-light);
  border-radius: var(--radius); color: var(--nka-text); font-size: 0.95rem;
}
.form-group input:focus { outline: none; border-color: var(--nka-gold); }
.flash { padding: 0.75rem 1rem; border-radius: var(--radius); margin-bottom: 1rem; font-size: 0.9rem; }
.flash-error { background: rgba(231,76,60,0.15); color: var(--nka-red); border: 1px solid var(--nka-red); }