* {
  box-sizing: border-box;
}

:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --text: #172033;
  --muted: #667085;
  --border: #d8dee9;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-soft: #eaf1ff;
}

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
}

.container {
  width: min(960px, calc(100% - 32px));
  margin: 48px auto;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3rem);
}

.subtitle {
  margin: 8px 0 28px;
  color: var(--muted);
}

.summary-grid,
.equivalences-grid {
  display: grid;
  gap: 16px;
}

.summary-grid {
  grid-template-columns: repeat(3, 1fr);
  margin-bottom: 20px;
}

.summary-card,
.converter-card,
.result-card,
.equivalence-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
}

.summary-card,
.equivalence-card {
  padding: 18px;
}

.summary-card span,
.result-card span,
.equivalence-card span {
  display: block;
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 6px;
}

.summary-card strong,
.equivalence-card strong {
  font-size: 1.2rem;
}

.converter-card {
  padding: 24px;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

label {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-weight: 600;
}

input,
select,
button {
  font: inherit;
}

input,
select {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 14px;
  background: #fff;
  color: var(--text);
}

input:focus,
select:focus,
button:focus-visible {
  outline: 3px solid rgba(37, 99, 235, 0.2);
  outline-offset: 2px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

button {
  border: 0;
  border-radius: 12px;
  padding: 12px 18px;
  cursor: pointer;
  background: var(--primary);
  color: #fff;
  font-weight: 700;
}

button:hover {
  background: var(--primary-dark);
}

button.secondary {
  background: #eef1f6;
  color: var(--text);
}

.result-card {
  margin-top: 20px;
  padding: 22px;
  background: var(--primary-soft);
  border-color: #bfd1ff;
}

.result-card strong {
  display: block;
  font-size: clamp(1.4rem, 4vw, 2rem);
}

.equivalences-section {
  margin-top: 28px;
}

.equivalences-section h2 {
  margin-bottom: 14px;
}

.equivalences-grid {
  grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 760px) {
  .summary-grid,
  .form-grid,
  .equivalences-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 520px) {
  .container {
    width: min(100% - 20px, 960px);
    margin: 24px auto;
  }

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

  .actions button {
    width: 100%;
  }
}