/* Calculadora de Depreciación — tema banca moderna */
:root {
  --ink: #0d1b2e;
  --ink-2: #13253f;
  --panel: #ffffff;
  --bg: #f4f6fa;
  --line: #e3e8f0;
  --text: #1c2b3f;
  --muted: #5c6b82;
  --green: #2fbf8f;
  --gold: #e8c15a;
  --blue: #7aa5ff;
  --radius: 12px;
  --shadow: 0 1px 2px rgba(13,27,46,.05), 0 8px 28px rgba(13,27,46,.09);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, "Segoe UI", Roboto, Inter, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}
.sr-only {
  position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0);
}

/* ---- Hero ---- */
.hero {
  background:
    radial-gradient(900px 380px at 85% -60%, rgba(47,191,143,.18), transparent),
    radial-gradient(700px 300px at 10% 120%, rgba(122,165,255,.12), transparent),
    linear-gradient(160deg, var(--ink) 0%, var(--ink-2) 100%);
  color: #eef2f8;
  padding-bottom: clamp(56px, 9vw, 96px);
}
.nav {
  max-width: 1080px; margin: 0 auto;
  display: flex; justify-content: space-between; align-items: center;
  padding: 20px 24px;
}
.nav__brand {
  font-weight: 800; letter-spacing: .04em; font-size: 1.05rem;
  color: var(--gold);
}
.nav__links { display: flex; gap: 22px; }
.nav__links a {
  color: #aebbd0; text-decoration: none; font-size: .86rem;
  letter-spacing: .06em; transition: color .2s;
}
.nav__links a:hover { color: #fff; }
.hero__inner { max-width: 1080px; margin: 0 auto; padding: clamp(32px, 7vw, 72px) 24px 0; }
.hero__kicker {
  font-size: .75rem; letter-spacing: .28em; text-transform: uppercase;
  color: var(--green); margin-bottom: 14px;
}
.hero h1 {
  font-size: clamp(2.1rem, 6vw, 3.4rem);
  letter-spacing: -.02em; line-height: 1.08; font-weight: 800;
  animation: rise .35s ease both;
}
.hero__sub {
  max-width: 560px; margin-top: 16px; color: #aebbd0; font-size: 1.02rem;
}
@keyframes rise { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: none; } }

/* ---- Tool ---- */
.tool { max-width: 1080px; margin: -44px auto 0; padding: 0 24px; position: relative; z-index: 2; }
.panel {
  background: var(--panel); border-radius: var(--radius); box-shadow: var(--shadow);
  display: grid; grid-template-columns: 1fr 1fr 0.6fr 0.6fr auto;
  gap: 16px; align-items: end; padding: 22px;
}
.field label {
  display: block; font-size: .72rem; font-weight: 600;
  letter-spacing: .12em; text-transform: uppercase; color: var(--muted); margin-bottom: 6px;
}
.field input, .field select {
  width: 100%; min-height: 44px; padding: 0 12px;
  border: 1px solid var(--line); border-radius: 8px;
  font: inherit; font-size: 1rem; color: var(--text); background: #fafbfd;
  transition: border-color .2s, box-shadow .2s;
}
.field input:focus, .field select:focus {
  outline: none; border-color: var(--green); box-shadow: 0 0 0 3px rgba(47,191,143,.18);
}
.btn-calc {
  min-height: 44px; padding: 0 26px; border: none; border-radius: 8px;
  background: linear-gradient(135deg, #23a67c, var(--green)); color: #fff;
  font: inherit; font-weight: 700; letter-spacing: .04em; cursor: pointer;
  transition: transform .15s, box-shadow .2s, filter .2s;
  box-shadow: 0 4px 14px rgba(47,191,143,.35);
}
.btn-calc:hover { filter: brightness(1.06); transform: translateY(-1px); }
.btn-calc:active { transform: translateY(0); }

.tool__error {
  margin-top: 14px; background: #fdf0f0; border: 1px solid #f2c8c8;
  color: #a13b3b; border-radius: 8px; padding: 10px 14px; font-size: .92rem;
}

/* ---- Resultados ---- */
.resultados { margin-top: 28px; animation: rise .3s ease both; position: relative; }
.resumen {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px; margin-bottom: 20px;
}
.resumen__card {
  background: var(--panel); border: 1px solid var(--line); border-radius: 10px;
  padding: 14px 16px; box-shadow: 0 1px 3px rgba(13,27,46,.04);
}
.resumen__label {
  display: block; font-size: .7rem; letter-spacing: .12em;
  text-transform: uppercase; color: var(--muted); margin-bottom: 4px;
}
.resumen__valor { font-size: 1.02rem; font-variant-numeric: tabular-nums; }

#grafico {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  display: block; width: 100%;
}
.leyenda {
  display: flex; flex-wrap: wrap; gap: 18px; margin: 14px 4px 4px;
  font-size: .84rem; color: var(--muted);
}
.leyenda i {
  display: inline-block; width: 11px; height: 11px; border-radius: 3px;
  margin-right: 7px; vertical-align: -1px;
}

.tabs { display: flex; gap: 8px; margin-top: 22px; flex-wrap: wrap; }
.tabs button {
  padding: 9px 18px; min-height: 40px; border: 1px solid var(--line);
  background: var(--panel); color: var(--muted); border-radius: 999px;
  font: inherit; font-size: .88rem; cursor: pointer; transition: all .2s;
}
.tabs button:hover { border-color: var(--green); color: var(--text); }
.tabs button[aria-selected="true"] {
  background: var(--ink); border-color: var(--ink); color: #fff; font-weight: 600;
}
.tabs button:focus-visible { outline: 2px solid var(--green); outline-offset: 2px; }

.tabla-wrap {
  margin-top: 14px; background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); box-shadow: var(--shadow);
  overflow-x: auto; max-height: 420px; overflow-y: auto;
}
table { width: 100%; border-collapse: collapse; font-variant-numeric: tabular-nums; }
th, td { padding: 11px 18px; text-align: right; white-space: nowrap; }
th:first-child, td:first-child { text-align: left; }
thead th {
  position: sticky; top: 0; z-index: 1; background: var(--ink); color: #dbe4f0;
  font-size: .72rem; letter-spacing: .1em; text-transform: uppercase; font-weight: 600;
}
tbody tr { border-top: 1px solid var(--line); transition: background .15s; }
tbody tr:hover { background: #f6f9fc; }
tbody td:last-child { font-weight: 600; }
.c-libros { color: var(--ink); }

.acciones { display: flex; gap: 12px; margin-top: 16px; flex-wrap: wrap; }
.btn-ghost {
  display: inline-flex; align-items: center; gap: 8px;
  min-height: 44px; padding: 0 20px; background: var(--panel);
  border: 1px solid var(--line); border-radius: 8px; color: var(--text);
  font: inherit; font-size: .92rem; cursor: pointer; transition: all .2s;
}
.btn-ghost:hover { border-color: var(--green); color: var(--green); }
.toast {
  position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  background: var(--ink); color: #fff; padding: 8px 18px; border-radius: 999px;
  font-size: .85rem; box-shadow: var(--shadow); animation: rise .25s ease both;
}

/* ---- Contenido editorial ---- */
.contenido { max-width: 880px; margin: 64px auto 0; padding: 0 24px; }
.contenido h2 {
  font-size: clamp(1.4rem, 3.4vw, 1.9rem); letter-spacing: -.01em;
  margin-bottom: 18px; color: var(--ink);
}
.contenido p { color: var(--muted); margin-bottom: 10px; }
.metodos-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px;
}
.metodo-card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 22px;
  box-shadow: 0 1px 3px rgba(13,27,46,.04);
  border-top: 3px solid var(--green); transition: transform .2s, box-shadow .2s;
}
.metodo-card:nth-child(2) { border-top-color: var(--gold); }
.metodo-card:nth-child(3) { border-top-color: var(--blue); }
.metodo-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.metodo-card h3 { font-size: 1.05rem; margin-bottom: 8px; color: var(--ink); }
.metodo-card p { font-size: .93rem; margin: 0; }

.pasos { list-style: none; counter-reset: paso; }
.pasos li {
  counter-increment: paso; position: relative; padding-left: 48px;
  margin-bottom: 14px; color: var(--muted);
}
.pasos li::before {
  content: counter(paso); position: absolute; left: 0; top: 2px;
  width: 30px; height: 30px; border-radius: 50%;
  background: var(--ink); color: var(--gold); font-weight: 700; font-size: .9rem;
  display: grid; place-items: center;
}
.pasos strong { color: var(--text); }

details {
  background: var(--panel); border: 1px solid var(--line); border-radius: 10px;
  padding: 14px 18px; margin-bottom: 10px;
}
details summary { cursor: pointer; font-weight: 600; color: var(--ink); }
details p { margin: 10px 0 0; }

.footer {
  margin-top: 72px; background: var(--ink); color: #aebbd0;
  padding: 36px 24px; text-align: center; font-size: .88rem;
}
.footer nav { display: flex; gap: 20px; justify-content: center; margin-top: 12px; flex-wrap: wrap; }
.footer a { color: #8fa0ba; text-decoration: none; }
.footer a:hover { color: #fff; }

/* ---- Responsive ---- */
@media (max-width: 900px) {
  .panel { grid-template-columns: 1fr 1fr; }
  .btn-calc { grid-column: 1 / -1; }
}
@media (max-width: 560px) {
  .nav__links { display: none; }
  .panel { grid-template-columns: 1fr; padding: 18px; }
  th, td { padding: 10px 12px; }
}