:root {
  --bg: #090d18;
  --panel: #111827;
  --panel-2: #171f31;
  --line: #293249;
  --text: #f5f7ff;
  --muted: #a9b3c9;
  --accent: #8b5cf6;
  --accent-2: #22d3ee;
  --success: #34d399;
  --danger: #fb7185;
  --warning: #fbbf24;
  --shadow: 0 24px 60px rgba(0,0,0,.28);
  --radius: 20px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background:
    radial-gradient(circle at 15% 0%, rgba(139,92,246,.18), transparent 28rem),
    radial-gradient(circle at 90% 10%, rgba(34,211,238,.12), transparent 25rem),
    var(--bg);
  color: var(--text);
  line-height: 1.55;
}

a { color: inherit; text-decoration: none; }
button, input, textarea { font: inherit; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(14px);
  background: rgba(9,13,24,.78);
  border-bottom: 1px solid rgba(255,255,255,.07);
}
.nav {
  max-width: 1180px;
  margin: auto;
  padding: 14px 22px;
  display: flex;
  gap: 18px;
  align-items: center;
}
.brand { font-weight: 800; letter-spacing: -.02em; margin-right: auto; }
.brand span { color: var(--accent-2); }
.nav-links { display: flex; gap: 14px; flex-wrap: wrap; }
.nav-links a { color: var(--muted); font-size: .9rem; }
.nav-links a:hover { color: var(--text); }

main { max-width: 1180px; margin: auto; padding: 0 22px 64px; }
.hero {
  min-height: 460px;
  display: grid;
  grid-template-columns: 1.2fr .8fr;
  align-items: center;
  gap: 42px;
  padding: 70px 0 42px;
}
.eyebrow {
  display: inline-flex;
  padding: 6px 11px;
  border: 1px solid rgba(139,92,246,.45);
  background: rgba(139,92,246,.12);
  border-radius: 999px;
  color: #c4b5fd;
  font-weight: 700;
  font-size: .8rem;
  letter-spacing: .08em;
  text-transform: uppercase;
}
h1 { font-size: clamp(2.6rem, 6vw, 5.5rem); line-height: .96; letter-spacing: -.055em; margin: 18px 0; }
.gradient-text {
  background: linear-gradient(105deg, #c4b5fd 10%, #67e8f9 85%);
  -webkit-background-clip: text;
  color: transparent;
}
.hero p { max-width: 720px; color: var(--muted); font-size: 1.08rem; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 24px; }

.hero-card, .panel, .info-card, .step-card, .attack-row {
  border: 1px solid rgba(255,255,255,.08);
  background: linear-gradient(180deg, rgba(255,255,255,.055), rgba(255,255,255,.025));
  box-shadow: var(--shadow);
}
.hero-card {
  border-radius: 24px;
  padding: 22px;
  transform: rotate(1.5deg);
}
.hero-card .formula { font-size: 1.15rem; display: grid; gap: 12px; }
.formula-line {
  padding: 14px;
  border-radius: 14px;
  background: rgba(0,0,0,.22);
  border: 1px solid var(--line);
}
.formula-line strong { color: var(--accent-2); }

section { scroll-margin-top: 84px; margin-top: 64px; }
.section-head { margin-bottom: 20px; }
.section-head h2 { margin: 0 0 6px; font-size: clamp(1.8rem, 4vw, 2.6rem); letter-spacing: -.035em; }
.section-head p { margin: 0; color: var(--muted); max-width: 780px; }

.grid-2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.panel { border-radius: var(--radius); padding: 22px; }
.panel h3 { margin: 0 0 18px; font-size: 1.22rem; }

label { display: block; color: #d9def0; font-weight: 700; margin: 14px 0 7px; }
textarea, input {
  width: 100%;
  border: 1px solid var(--line);
  color: var(--text);
  background: rgba(0,0,0,.24);
  border-radius: 12px;
  padding: 12px 14px;
  outline: none;
  transition: .2s ease;
}
textarea { min-height: 118px; resize: vertical; }
textarea:focus, input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(139,92,246,.14);
}
.field-row { display: grid; grid-template-columns: 140px 1fr; gap: 12px; align-items: end; }

.btn {
  border: 0;
  cursor: pointer;
  border-radius: 12px;
  padding: 11px 16px;
  font-weight: 800;
  color: white;
  background: linear-gradient(135deg, var(--accent), #6d28d9);
  transition: transform .15s ease, opacity .15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn.secondary { background: #20283a; color: #e6ebfa; border: 1px solid var(--line); }
.btn.small { padding: 7px 10px; font-size: .82rem; }

.result-box {
  margin-top: 16px;
  padding: 14px;
  border-radius: 14px;
  background: rgba(34,211,238,.07);
  border: 1px solid rgba(34,211,238,.25);
}
.result-head { display: flex; align-items: center; gap: 10px; margin-bottom: 8px; color: var(--muted); font-size: .85rem; }
.result-head .btn { margin-left: auto; }
.result-output { font-size: 1.18rem; font-weight: 800; word-break: break-word; color: #a5f3fc; }
.error {
  margin-top: 12px;
  padding: 10px 12px;
  border: 1px solid rgba(251,113,133,.35);
  background: rgba(251,113,133,.1);
  color: #fecdd3;
  border-radius: 11px;
  font-weight: 700;
}
.muted { color: var(--muted); }

.steps-wrap { margin-top: 18px; }
.steps-wrap h4 { margin: 0 0 10px; }
.steps-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 10px; }
.step-card { border-radius: 14px; padding: 12px; box-shadow: none; }
.step-number { color: var(--muted); font-size: .75rem; }
.step-letters { display: flex; gap: 9px; align-items: center; font-size: 1.35rem; margin: 7px 0; }
.step-letters span { color: var(--accent-2); }
.step-card code, .attack-row code { color: #ddd6fe; }
.step-card small { display: block; color: var(--muted); margin-top: 6px; }
.full-row { grid-column: 1 / -1; }

.explain-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.info-card { border-radius: 18px; padding: 18px; box-shadow: none; }
.info-card .number {
  width: 34px; height: 34px; display: grid; place-items: center;
  border-radius: 10px; background: rgba(139,92,246,.16); color: #c4b5fd; font-weight: 900;
}
.info-card h3 { margin: 14px 0 7px; }
.info-card p { margin: 0; color: var(--muted); }

.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 16px; }
table { width: 100%; border-collapse: collapse; min-width: 850px; background: rgba(0,0,0,.15); }
th, td { text-align: left; padding: 13px 14px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { color: #d9def0; background: rgba(255,255,255,.04); font-size: .84rem; }
td { color: var(--muted); }
tbody tr:last-child td { border-bottom: 0; }
.status {
  display: inline-flex; padding: 4px 8px; border-radius: 999px; font-size: .76rem; font-weight: 900;
}
.status.pass { color: #a7f3d0; background: rgba(52,211,153,.12); border: 1px solid rgba(52,211,153,.28); }
.status.fail { color: #fecdd3; background: rgba(251,113,133,.1); border: 1px solid rgba(251,113,133,.28); }
.test-toolbar { display: flex; gap: 12px; align-items: center; margin-bottom: 14px; flex-wrap: wrap; }
.test-summary { font-weight: 800; }
.all-pass { color: var(--success); }
.has-fail { color: var(--danger); }

.attack-layout { display: grid; grid-template-columns: .82fr 1.18fr; gap: 20px; }
.attack-note {
  padding: 14px;
  border-radius: 14px;
  background: rgba(251,191,36,.07);
  border: 1px solid rgba(251,191,36,.25);
  color: #fde68a;
  margin: 14px 0;
}
.attack-results {
  max-height: 540px;
  overflow: auto;
  display: grid;
  gap: 8px;
  padding-right: 4px;
}
.attack-row {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 12px;
  align-items: center;
  border-radius: 12px;
  padding: 10px 12px;
  box-shadow: none;
}
.key-badge {
  display: inline-flex; justify-content: center; padding: 5px 7px; border-radius: 8px;
  background: rgba(139,92,246,.15); color: #c4b5fd; font-weight: 800; font-size: .8rem;
}
.attack-row code { word-break: break-word; }

.validation-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; padding: 0; list-style: none; }
.validation-list li {
  border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px;
  background: rgba(255,255,255,.025); color: var(--muted);
}
.validation-list strong { color: var(--text); }

.presentation-card {
  border: 1px solid rgba(139,92,246,.3);
  border-radius: 20px;
  background: linear-gradient(135deg, rgba(139,92,246,.10), rgba(34,211,238,.05));
  padding: 22px;
}
.presentation-card ol { color: var(--muted); }
.presentation-card strong { color: var(--text); }
code { font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace; }

footer {
  color: var(--muted);
  border-top: 1px solid rgba(255,255,255,.07);
  padding: 24px 22px 42px;
  text-align: center;
  font-size: .88rem;
}

@media (max-width: 860px) {
  .hero, .grid-2, .attack-layout { grid-template-columns: 1fr; }
  .hero { padding-top: 48px; min-height: unset; }
  .hero-card { transform: none; }
  .explain-grid { grid-template-columns: 1fr; }
  .nav-links { display: none; }
}
@media (max-width: 560px) {
  main { padding-left: 15px; padding-right: 15px; }
  .field-row, .validation-list { grid-template-columns: 1fr; }
  h1 { font-size: 3rem; }
}