:root {
  color-scheme: dark;
  --bg-main: #07101b;
  --bg-secondary: #101c2e;
  --surface: rgba(14, 24, 41, 0.86);
  --surface-strong: rgba(19, 33, 56, 0.96);
  --surface-soft: rgba(18, 31, 53, 0.74);
  --border: rgba(110, 177, 255, 0.2);
  --border-strong: rgba(110, 177, 255, 0.34);
  --text-main: #ebf3ff;
  --text-soft: #a5b8d7;
  --text-muted: #7e92b3;
  --blue-main: #5aa7ff;
  --blue-strong: #2e7cf3;
  --cyan-soft: #7bd9ff;
  --indigo-soft: #8e8cff;
  --success-soft: #84f1c8;
  --warning-soft: #ffd27d;
  --danger-soft: #ff9aa9;
  --shadow: 0 20px 60px rgba(0, 0, 0, 0.34);
  --radius-lg: 1.35rem;
  --radius-md: 1rem;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  background:
    radial-gradient(circle at 10% 0%, rgba(90, 167, 255, 0.16), transparent 28%),
    radial-gradient(circle at 92% 8%, rgba(123, 217, 255, 0.11), transparent 24%),
    linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-main) 100%);
  color: var(--text-main);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

button,
input,
select {
  font: inherit;
}

code {
  color: var(--cyan-soft);
  background: rgba(123, 217, 255, 0.08);
  padding: 0.15rem 0.45rem;
  border-radius: 0.45rem;
  white-space: nowrap;
}

h1,
h2,
p {
  margin-top: 0;
}

h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.05;
  margin-bottom: 0.75rem;
}

h2 {
  font-size: clamp(1.25rem, 2.5vw, 1.65rem);
  line-height: 1.15;
  margin-bottom: 0.65rem;
}

small,
.muted {
  color: var(--text-soft);
}

.hero-glow {
  position: fixed;
  inset: auto 0 0 0;
  height: 280px;
  pointer-events: none;
  background: radial-gradient(circle at center, rgba(90, 167, 255, 0.07), transparent 55%);
  filter: blur(18px);
}

.app-navbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 0.7rem clamp(1rem, 4vw, 2rem);
  background: rgba(8, 15, 28, 0.78);
  border-bottom: 1px solid var(--border-strong);
  backdrop-filter: blur(14px);
}

.brand {
  color: var(--text-main);
  font-weight: 800;
  letter-spacing: 0.01em;
  text-decoration: none;
  white-space: nowrap;
}

.nav-pills {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.nav-link {
  color: var(--text-soft);
  text-decoration: none;
  border-radius: 999px;
  padding: 0.55rem 0.9rem;
  transition: 0.22s ease;
}

.nav-link:hover,
.nav-link.active {
  color: var(--text-main);
  background: rgba(90, 167, 255, 0.14);
  box-shadow: inset 0 0 0 1px rgba(110, 177, 255, 0.14);
}

.page-shell {
  width: min(1120px, calc(100% - 2rem));
  margin: 0 auto;
  padding: clamp(1.25rem, 4vw, 3rem) 0;
  display: grid;
  gap: 1.5rem;
}

.app-card,
.result-card,
.reference-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: clamp(1.1rem, 3vw, 1.85rem);
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
}

.result-card {
  background: var(--surface-strong);
}

.reference-panel {
  display: grid;
  gap: 1.25rem;
  background: rgba(13, 23, 39, 0.66);
}

.section-header {
  margin-bottom: 1.35rem;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.76rem;
  color: var(--blue-main);
  font-weight: 900;
  margin-bottom: 0.55rem;
}

.form-grid,
.settings-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.field,
.field span {
  display: grid;
  gap: 0.45rem;
}

.field span {
  color: var(--text-main);
  font-weight: 800;
}

.field small {
  font-size: 0.86rem;
}

.wide {
  grid-column: 1 / -1;
}

input,
select {
  width: 100%;
  background: rgba(7, 13, 23, 0.92);
  border: 1px solid rgba(110, 177, 255, 0.22);
  color: var(--text-main);
  border-radius: var(--radius-md);
  padding: 0.92rem 1rem;
  outline: none;
}

input:focus,
select:focus {
  background: rgba(7, 13, 23, 1);
  border-color: rgba(90, 167, 255, 0.75);
  box-shadow: 0 0 0 0.2rem rgba(90, 167, 255, 0.16);
}

input::placeholder {
  color: #6b84a8;
}

.formula-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  background: linear-gradient(180deg, rgba(90, 167, 255, 0.1), rgba(90, 167, 255, 0.05));
  border: 1px solid rgba(90, 167, 255, 0.14);
  border-radius: var(--radius-md);
  padding: 0.95rem 1rem;
  color: var(--text-soft);
}

.primary-button,
.ghost-button,
.copy-button {
  cursor: pointer;
  border: 0;
  border-radius: var(--radius-md);
  font-weight: 900;
  transition: 0.18s ease;
}

.primary-button {
  background: linear-gradient(135deg, var(--blue-main), var(--blue-strong));
  color: white;
  padding: 0.98rem 1rem;
  box-shadow: 0 10px 24px rgba(46, 124, 243, 0.25);
}

.primary-button:hover,
.ghost-button:hover,
.copy-button:hover {
  transform: translateY(-1px);
  filter: brightness(1.06);
}

.ghost-button,
.copy-button {
  background: rgba(123, 217, 255, 0.08);
  color: var(--cyan-soft);
  border: 1px solid rgba(123, 217, 255, 0.18);
  padding: 0.7rem 0.9rem;
}

.compact-result {
  margin-bottom: 1.35rem;
  display: none;
}

.compact-result.visible {
  display: block;
}

.result-split {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.result-stack {
  display: flex;
  align-items: flex-end;
  flex-direction: column;
  gap: 0.65rem;
}

.result-pill {
  display: inline-flex;
  align-items: center;
  padding: 0.6rem 0.95rem;
  border-radius: 999px;
  background: rgba(123, 217, 255, 0.1);
  color: var(--cyan-soft);
  border: 1px solid rgba(123, 217, 255, 0.18);
  font-size: 0.92rem;
  white-space: nowrap;
}

.display-result {
  font-size: clamp(2.1rem, 8vw, 4rem);
  font-weight: 950;
  line-height: 0.95;
  margin-bottom: 0.45rem;
}

.display-result span {
  font-size: 0.45em;
  color: var(--text-soft);
}

.stat-grid,
.reference-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 0.85rem;
  margin-top: 1rem;
}

.stat-item,
.reference-item,
.history-item {
  display: flex;
  flex-direction: column;
  gap: 0.18rem;
  padding: 0.95rem 1rem;
  border-radius: var(--radius-md);
  background: rgba(4, 11, 21, 0.28);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.stat-label,
.reference-item span,
.history-item span {
  color: var(--text-soft);
  font-size: 0.84rem;
  font-weight: 800;
}

.stat-item strong,
.reference-item strong,
.history-item strong {
  color: var(--text-main);
}

.distribution-section {
  display: none;
}

.distribution-section.visible {
  display: block;
}

.distribution-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(235px, 1fr));
  gap: 1rem;
  margin-top: 1.25rem;
}

.distribution-card {
  border-radius: 1.2rem;
  border: 1px solid transparent;
  padding: 1.1rem;
  background: var(--surface-soft);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.02);
}

.distribution-topline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 0.9rem;
}

.distribution-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.7rem;
  border-radius: 999px;
  font-size: 0.82rem;
  font-weight: 800;
  background: rgba(255, 255, 255, 0.05);
}

.distribution-percent {
  color: var(--text-soft);
  font-size: 0.86rem;
  font-weight: 800;
}

.distribution-main-value {
  font-size: 1.85rem;
  font-weight: 950;
  line-height: 1.1;
  margin-bottom: 0.9rem;
}

.distribution-main-value span {
  font-size: 0.55em;
  color: var(--text-soft);
  font-weight: 800;
}

.distribution-details {
  display: grid;
  gap: 0.7rem;
  margin-bottom: 0.9rem;
}

.distribution-detail {
  display: flex;
  flex-direction: column;
  gap: 0.18rem;
  padding: 0.75rem 0.85rem;
  border-radius: 0.95rem;
  background: rgba(4, 11, 21, 0.22);
}

.distribution-detail-label,
.distribution-hint {
  color: var(--text-soft);
  font-size: 0.85rem;
}

.dist-50 { background: linear-gradient(180deg, rgba(74, 162, 255, 0.16), rgba(74, 162, 255, 0.07)); border-color: rgba(74, 162, 255, 0.22); }
.dist-70 { background: linear-gradient(180deg, rgba(93, 210, 255, 0.16), rgba(93, 210, 255, 0.07)); border-color: rgba(93, 210, 255, 0.22); }
.dist-75 { background: linear-gradient(180deg, rgba(93, 186, 255, 0.18), rgba(93, 186, 255, 0.07)); border-color: rgba(93, 186, 255, 0.22); }
.dist-80 { background: linear-gradient(180deg, rgba(92, 159, 255, 0.2), rgba(92, 159, 255, 0.07)); border-color: rgba(92, 159, 255, 0.22); }
.dist-90 { background: linear-gradient(180deg, rgba(104, 128, 255, 0.2), rgba(104, 128, 255, 0.07)); border-color: rgba(104, 128, 255, 0.24); }
.dist-100 { background: linear-gradient(180deg, rgba(126, 111, 255, 0.2), rgba(126, 111, 255, 0.08)); border-color: rgba(126, 111, 255, 0.24); }
.dist-110 { background: linear-gradient(180deg, rgba(151, 102, 255, 0.22), rgba(151, 102, 255, 0.08)); border-color: rgba(151, 102, 255, 0.26); }

.settings-card summary {
  cursor: pointer;
  list-style: none;
}

.settings-card summary::-webkit-details-marker {
  display: none;
}

.settings-card summary span {
  display: grid;
  gap: 0.25rem;
}

.settings-grid {
  margin-top: 1.2rem;
}

.history-list {
  display: grid;
  gap: 0.75rem;
  margin-top: 1rem;
}

.history-item {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 1rem;
}

.history-item p {
  margin: 0.2rem 0 0;
  color: var(--text-soft);
}

.alert {
  color: var(--danger-soft);
  background: rgba(255, 154, 169, 0.08);
  border: 1px solid rgba(255, 154, 169, 0.18);
  border-radius: var(--radius-md);
  padding: 0.95rem 1rem;
  margin-bottom: 1rem;
}

.toast {
  position: fixed;
  right: 1rem;
  bottom: 1rem;
  z-index: 50;
  max-width: min(360px, calc(100vw - 2rem));
  padding: 0.9rem 1rem;
  border-radius: var(--radius-md);
  color: var(--text-main);
  background: rgba(8, 15, 28, 0.94);
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translateY(0.75rem);
  pointer-events: none;
  transition: 0.18s ease;
}

.toast.visible {
  opacity: 1;
  transform: translateY(0);
}

.calculator-panel[data-page="plates"] {
  display: none;
}

body.show-plates .calculator-panel[data-page="total"] {
  display: none;
}

body.show-plates .calculator-panel[data-page="plates"] {
  display: block;
}

@media (max-width: 720px) {
  .app-navbar {
    align-items: flex-start;
    flex-direction: column;
  }

  .nav-pills {
    justify-content: flex-start;
  }

  .form-grid,
  .settings-grid {
    grid-template-columns: 1fr;
  }

  .formula-box,
  .result-split,
  .history-item {
    align-items: flex-start;
    flex-direction: column;
    grid-template-columns: 1fr;
  }

  .result-stack {
    align-items: flex-start;
  }
}