:root {
  color-scheme: light dark;
  --bg: #f5f2ed;
  --bg-strong: #ebe6dc;
  --surface: #ffffff;
  --surface-strong: #f2f0eb;
  --text: #1d1f24;
  --muted: #555c68;
  --accent: #1f6f8b;
  --accent-strong: #134f64;
  --border: #d7d0c4;
  --shadow: 0 24px 60px rgba(14, 18, 26, 0.1);
  --chip: #eef0f4;
  --focus: rgba(31, 111, 139, 0.25);
  --action-primary-bg: #ffffff;
  --action-primary-text: #1d1f24;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0c121a;
    --bg-strong: #121a25;
    --surface: #151e2a;
    --surface-strong: #1c2635;
    --text: #e6edf6;
    --muted: #9aa7bd;
    --accent: #64b4ff;
    --accent-strong: #3d91e0;
    --border: #243245;
    --shadow: 0 24px 60px rgba(0, 0, 0, 0.4);
    --chip: #1e2a3a;
    --focus: rgba(100, 180, 255, 0.25);
    --action-primary-bg: #f2f6ff;
    --action-primary-text: #0c121a;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Space Grotesk", "Segoe UI", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top, rgba(31, 111, 139, 0.12), transparent 60%),
    linear-gradient(180deg, var(--bg), var(--bg-strong));
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 48px 20px 64px;
}

.bg-glow {
  position: fixed;
  inset: -40% auto auto -20%;
  width: 520px;
  height: 520px;
  background: radial-gradient(circle at center, rgba(100, 180, 255, 0.2), transparent 70%);
  filter: blur(20px);
  opacity: 0.7;
  pointer-events: none;
  animation: drift 18s ease-in-out infinite;
}

@media (prefers-color-scheme: light) {
  .bg-glow {
    background: radial-gradient(circle at center, rgba(31, 111, 139, 0.2), transparent 70%);
  }
}

@keyframes drift {
  0% {
    transform: translate3d(0, 0, 0);
  }
  50% {
    transform: translate3d(40px, 20px, 0);
  }
  100% {
    transform: translate3d(0, 0, 0);
  }
}

.shell {
  width: min(960px, 100%);
  display: grid;
  gap: 24px;
  position: relative;
  z-index: 1;
}

.brand {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
}

.brand-eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 12px;
  color: var(--muted);
  margin: 0 0 12px;
}

h1 {
  margin: 0 0 10px;
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 600;
}

.brand-subtitle {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
}

.tabs {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  background: var(--surface);
  padding: 6px;
  border-radius: 18px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.tab {
  appearance: none;
  border: none;
  background: transparent;
  color: var(--muted);
  padding: 12px 16px;
  border-radius: 14px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.tab.is-active {
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: #ffffff;
  box-shadow: 0 6px 18px rgba(31, 111, 139, 0.35);
}

.panel {
  display: none;
  flex-direction: column;
  gap: 18px;
  animation: fadeUp 0.35s ease;
}

.panel.is-active {
  display: flex;
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.output {
  display: grid;
  gap: 14px;
  padding: 22px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.output-value {
  font-family: "JetBrains Mono", "SFMono-Regular", monospace;
  font-size: clamp(18px, 2.6vw, 24px);
  word-break: break-all;
  padding: 8px 0;
  cursor: pointer;
  text-align: center;
}

.output-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px 18px;
  font-size: 13px;
  color: var(--muted);
  border-top: 1px solid var(--border);
  padding-top: 12px;
}

.strength {
  font-weight: 600;
}

.strength--very-weak {
  color: #f15b5b;
}

.strength--weak {
  color: #f48c42;
}

.strength--fair {
  color: #d7b23f;
}

.strength--strong {
  color: #45b880;
}

.strength--very-strong {
  color: #4fa0ff;
}

.action-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.action-button {
  appearance: none;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
  padding: 12px 18px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.action-button.primary {
  background: var(--action-primary-bg, #ffffff);
  color: var(--action-primary-text, #0c121a);
  border-color: transparent;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.15);
}

.action-button.secondary {
  background: transparent;
}

.action-button:hover {
  transform: translateY(-1px);
  border-color: var(--accent);
  box-shadow: 0 8px 16px rgba(31, 111, 139, 0.2);
}

.action-button svg {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

.btn-icon {
  display: inline-flex;
}

.status {
  min-height: 18px;
  margin: 0;
  font-size: 13px;
  color: var(--muted);
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 20px;
  display: grid;
  gap: 16px;
  box-shadow: var(--shadow);
}

.card h2 {
  margin: 0;
  font-size: 18px;
}

.field {
  display: grid;
  gap: 6px;
}

.field span {
  font-weight: 500;
}

input[type="number"],
input[type="text"],
select {
  width: 100%;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--surface-strong);
  color: var(--text);
  font-size: 15px;
}

input[type="number"]:focus,
input[type="text"]:focus,
select:focus,
button:focus {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
}

small {
  color: var(--muted);
  font-size: 12px;
}

.checks {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px 16px;
}

.checks label {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--chip);
  padding: 8px 12px;
  border-radius: 999px;
}

input[type="checkbox"] {
  width: 18px;
  height: 18px;
  accent-color: var(--accent);
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
}

.toggle {
  display: flex;
  align-items: center;
  gap: 10px;
}

.output-value::selection {
  background: var(--accent);
  color: #ffffff;
}

@media (max-width: 720px) {
  body {
    padding: 32px 16px 48px;
  }

  .brand {
    flex-direction: column;
    align-items: flex-start;
  }

  .output {
    padding: 18px;
  }

  .action-row {
    justify-content: stretch;
  }

  .action-button {
    flex: 1 1 160px;
    justify-content: center;
  }
}