/* ===== Calculadora — estilos ===== */

:root {
  --bg: #f4f5f7;
  --surface: #ffffff;
  --border: #e6e8ec;
  --border-strong: #d9dce1;
  --text: #363b42;
  --text-muted: #7c828b;
  --accent: #4f6ef0;
  --accent-soft: #eef1fe;
  --dark: #23262e;
  --radius: 12px;
  --font: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  --mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  padding: 40px 20px;
  display: flex;
  justify-content: center;
}

.app {
  width: 100%;
  max-width: 720px;
  display: flex;
  flex-direction: column;
  gap: 28px;
}

/* ---- Encabezado ---- */
.app__header h1 {
  margin: 0 0 6px;
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.app__header p {
  margin: 0;
  color: var(--text-muted);
  font-size: 15px;
}

/* ---- Tarjeta calculadora ---- */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 28px;
  box-shadow: 0 1px 3px rgba(35,38,46,0.06), 0 8px 24px rgba(35,38,46,0.04);
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.inputs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
}
.field input {
  font-family: var(--mono);
  font-size: 18px;
  font-weight: 500;
  color: var(--text);
  padding: 14px 16px;
  border: 1.5px solid var(--border-strong);
  border-radius: 10px;
  background: #fcfcfd;
  outline: none;
  transition: border-color .15s, background .15s;
}
.field input:focus {
  border-color: var(--accent);
  background: #fff;
}

/* ---- Botones de operación ---- */
.ops {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}
.op {
  cursor: pointer;
  font-family: var(--mono);
  font-size: 22px;
  font-weight: 700;
  color: #4a4f57;
  padding: 16px 0;
  border: 1.5px solid var(--border-strong);
  border-radius: 10px;
  background: #fff;
  transition: all .15s;
}
.op:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-soft);
}
.op:active { transform: translateY(1px); }

/* ---- Resultado ---- */
.result {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background: var(--dark);
  border-radius: 12px;
  padding: 20px 24px;
}
.result__label {
  font-size: 13px;
  font-weight: 600;
  color: #a9adb6;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.result__value {
  font-family: var(--mono);
  font-size: 30px;
  font-weight: 700;
  color: #fff;
  text-align: right;
  overflow-wrap: anywhere;
}

/* ---- Historial ---- */
.history { display: flex; flex-direction: column; gap: 14px; }
.history__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
}
.history__head h2 {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.link {
  cursor: pointer;
  font-family: var(--font);
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  background: none;
  border: none;
  padding: 4px;
}
.link:hover { color: #d0483a; }

.table-wrap {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(35,38,46,0.05);
}
table { width: 100%; border-collapse: collapse; font-size: 14px; }
thead tr { background: var(--bg); }
th {
  padding: 14px 18px;
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}
td {
  padding: 13px 18px;
  font-family: var(--mono);
  color: #3a3f47;
}
tbody tr { border-top: 1px solid #eef0f2; }
.op-col { font-weight: 700; color: var(--accent); }

.ta-left   { text-align: left; }
.ta-center { text-align: center; }
.ta-right  { text-align: right; }
td.ta-right { font-weight: 700; color: #2b2f36; }

/* ---- Responsive ---- */
@media (max-width: 520px) {
  body { padding: 24px 14px; }
  .card { padding: 20px; }
  .inputs { grid-template-columns: 1fr; }
  .result__value { font-size: 24px; }
  th, td { padding: 11px 12px; }
}