:root {
  --bg: #eef5ff;
  --bg-accent: #dfeaf8;
  --panel: #f8fbff;
  --border: #cddced;
  --text: #223247;
  --muted: #60738b;
  --strong: #40688d;
  --common: #4f6e86;
  --shadow: 0 10px 24px rgba(92, 127, 164, 0.05);
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Avenir Next", Avenir, "Segoe UI", sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, var(--bg) 0%, #f5f9ff 100%);
}

.shell {
  width: min(1320px, calc(100% - 1.5rem));
  margin: 0 auto;
  padding: 1.5rem 0 3rem;
}

.frame {
  background: rgba(248, 251, 255, 0.82);
  border: 1px solid var(--border);
  border-radius: 22px;
  box-shadow: var(--shadow);
  padding: 1.5rem;
  min-height: calc(100vh - 4.5rem);
}

.eyebrow,
.label {
  margin: 0;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 0.75rem;
  color: var(--muted);
}

h1 {
  margin: 0.2rem 0 0;
  font-family: Iowan Old Style, Palatino Linotype, Book Antiqua, Georgia, serif;
  font-size: clamp(1.8rem, 3.6vw, 2.6rem);
  line-height: 1.05;
  font-weight: 700;
  text-wrap: balance;
}

.intro {
  margin: 0;
  max-width: 34rem;
  font-size: 0.98rem;
  line-height: 1.5;
  color: var(--muted);
  text-wrap: pretty;
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: end;
  margin-bottom: 1rem;
}

.tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1rem;
  padding-bottom: 0.25rem;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}

.tab {
  width: auto;
  border: 1px solid transparent;
  border-radius: 999px;
  padding: 0.55rem 0.9rem;
  color: var(--muted);
  background: transparent;
  box-shadow: none;
  white-space: normal;
  text-wrap: balance;
}

.tab:hover {
  transform: none;
  box-shadow: none;
  background: #edf4fc;
}

.tab.is-active {
  border-color: var(--border);
  color: var(--text);
  background: #edf4fc;
}

.tab-panel {
  display: none;
}

.tab-panel.is-active {
  display: block;
}

.panel {
  display: grid;
  grid-template-columns: minmax(340px, 420px) minmax(420px, 1fr);
  gap: 1.25rem;
  align-items: stretch;
}

.controls,
.results {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  min-width: 0;
}

.controls {
  padding: 1.25rem;
}

.controls label {
  display: grid;
  gap: 0.45rem;
  margin-bottom: 1rem;
  font-weight: 600;
}

.controls input[type="number"] {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #ffffff;
  padding: 0.9rem 1rem;
  font: inherit;
  color: inherit;
}

.controls input[type="number"]:focus {
  outline: 2px solid rgba(64, 104, 141, 0.16);
  border-color: rgba(64, 104, 141, 0.35);
}

.controls input[type="number"]:disabled {
  color: var(--muted);
  background: #eef3f8;
  cursor: not-allowed;
}

.toggle {
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 0.65rem;
}

.toggle input {
  width: 1rem;
  height: 1rem;
  accent-color: var(--strong);
}

button {
  width: 100%;
  border: 0;
  border-radius: 12px;
  padding: 0.95rem 1.2rem;
  font: inherit;
  font-weight: 600;
  color: #f7fbff;
  background: #5f88ae;
  cursor: pointer;
  transition: background 140ms ease;
}

button:hover {
  background: #547b9f;
}

.results {
  padding: 1.5rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  align-content: start;
}

.stat {
  display: grid;
  gap: 0.2rem;
}

.stat,
.summary-card,
.simulation,
.error {
  min-width: 0;
}

.summary-card,
.simulation,
.error {
  grid-column: 1 / -1;
}

.value {
  margin: 0;
  font-size: clamp(1.8rem, 5vw, 3.25rem);
  line-height: 1.05;
  font-family: Iowan Old Style, Palatino Linotype, Book Antiqua, Georgia, serif;
  font-weight: 700;
  overflow-wrap: anywhere;
  word-break: break-word;
}

.summary-card,
.simulation {
  border: 1px solid #dbe6f2;
  border-radius: 14px;
  padding: 1rem 1.1rem;
  background: #fcfdff;
}

.summary {
  margin: 0.45rem 0 0;
  font-size: 1.06rem;
  line-height: 1.5;
  overflow-wrap: anywhere;
  text-wrap: pretty;
}

.simulation-line,
.error {
  margin: 0.4rem 0 0;
  font-size: 0.98rem;
  overflow-wrap: anywhere;
}

.muted {
  color: var(--muted);
}

.error {
  color: #9a4b46;
}

.status-common {
  color: var(--common);
}

.status-rare,
.status-extreme {
  color: var(--strong);
}

@media (max-width: 760px) {
  .shell {
    padding-top: 1rem;
  }

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

  .panel {
    grid-template-columns: 1fr;
  }

  .frame {
    padding: 1rem;
    min-height: auto;
  }

  .results {
    grid-template-columns: 1fr;
  }
}