/**
 * Estilos canónicos — Calculadora de acuario marino y de arrecife (AquaCalculator Web)
 * Tipografías corporativas: Outfit (títulos), Inter (cuerpo), JetBrains Mono (cifras/fórmulas)
 * Tema oscuro por defecto (:root, [data-theme="dark"]) con anulación limpia en [data-theme="light"].
 */

:root,
[data-theme="dark"] {
  --font-main: 'Inter', system-ui, -apple-system, sans-serif;
  --font-heading: 'Outfit', 'Inter', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --bg-page: #0b0f17;
  --bg-surface: #111827;
  --bg-card: #131b2e;
  --bg-card-header: #19243d;
  --bg-card-sub: #1a2434;
  --bg-input: #0f172a;
  --border-color: #243044;
  --border-focus: #38bdf8;

  --text-main: #f8fafc;
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;

  --primary: #38bdf8;
  --primary-color: #38bdf8;
  --primary-hover: #7dd3fc;
  --primary-light: rgba(56, 189, 248, 0.14);
  --reef-teal: #14b8a6;
  --reef-gradient: linear-gradient(135deg, #0284c7 0%, #0d9488 100%);

  --success: #10b981;
  --success-bg: rgba(16, 185, 129, 0.15);
  --success-text: #6ee7b7;
  --success-border: rgba(16, 185, 129, 0.35);

  --warning: #f59e0b;
  --warning-bg: rgba(245, 158, 11, 0.15);
  --warning-text: #fde68a;
  --warning-border: rgba(245, 158, 11, 0.35);

  --danger: #ef4444;
  --danger-bg: rgba(239, 68, 68, 0.15);
  --danger-text: #fca5a5;
  --danger-border: rgba(239, 68, 68, 0.35);

  --info-bg: rgba(56, 189, 248, 0.14);
  --info-text: #7dd3fc;
  --info-border: rgba(56, 189, 248, 0.35);

  --radius-sm: 8px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --shadow-card: 0 10px 25px -5px rgba(0, 0, 0, 0.35);
  --select-arrow: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
}

[data-theme="light"] {
  --bg-page: #f8fafc;
  --bg-surface: #f1f5f9;
  --bg-card: #ffffff;
  --bg-card-header: #f1f5f9;
  --bg-card-sub: #f1f5f9;
  --bg-input: #ffffff;
  --border-color: #e2e8f0;
  --border-focus: #0284c7;

  --text-main: #0f172a;
  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #475569;

  --primary: #0284c7;
  --primary-color: #0284c7;
  --primary-hover: #0369a1;
  --primary-light: rgba(2, 132, 199, 0.1);
  --reef-teal: #0d9488;
  --reef-gradient: linear-gradient(135deg, #0284c7 0%, #0d9488 100%);

  --success: #059669;
  --success-bg: #dcfce7;
  --success-text: #14532d;
  --success-border: rgba(22, 163, 74, 0.35);

  --warning: #d97706;
  --warning-bg: #fef3c7;
  --warning-text: #92400e;
  --warning-border: rgba(217, 119, 6, 0.35);

  --danger: #dc2626;
  --danger-bg: #fee2e2;
  --danger-text: #991b1b;
  --danger-border: rgba(220, 38, 38, 0.35);

  --info-bg: #e0f2fe;
  --info-text: #075985;
  --info-border: rgba(2, 132, 199, 0.35);

  --shadow-card: 0 4px 20px -2px rgba(15, 23, 42, 0.06);
  --select-arrow: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%23475569' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
}

/* Base y contención estricta */
*, *::before, *::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-main);
  background-color: var(--bg-page);
  color: var(--text-main);
  line-height: 1.55;
  overflow-x: clip;
  width: 100%;
  max-width: 100%;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, h4, h5, h6,
.brand-title,
.panel-title,
.tab-btn {
  font-family: var(--font-heading);
}

.mono, code, .metric-val, .formula-box {
  font-family: var(--font-mono);
}

svg {
  max-width: 100%;
}

/* Layout principal y barra lateral AdSense */
.tool-layout {
  max-width: 1200px;
  margin: 1.5rem auto 3rem;
  padding: 0 1rem;
  width: 100%;
  box-sizing: border-box;
  flex: 1 0 auto;
}

.tool-with-sidebar {
  display: flex;
  gap: 2rem;
  align-items: flex-start;
  width: 100%;
}

.tool-main-content {
  flex: 1 1 0%;
  min-width: 0;
  width: 100%;
}

/* Tarjeta interactiva principal */
.card-main {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 1.35rem;
  box-shadow: var(--shadow-card);
}

@media (min-width: 768px) {
  .card-main {
    padding: 1.85rem;
  }
}

/* Barra multiacuario */
.tank-manager-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding-bottom: 1.15rem;
  margin-bottom: 1.15rem;
  border-bottom: 1px solid var(--border-color);
}

.tank-selector-group {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  flex: 1 1 280px;
  min-width: 0;
}

.tank-badge-icon {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: var(--primary-light);
  color: var(--primary);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  border: 1px solid rgba(56, 189, 248, 0.25);
}

.tank-select-wrap {
  flex: 1 1 0%;
  min-width: 0;
}

.tank-actions-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

/* Botones generales y utilitarios */
.btn-secondary,
.btn-primary,
.btn-ghost,
.btn-preset,
.btn-pill {
  font-family: var(--font-main);
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: 9px;
  padding: 0.5rem 0.9rem;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  cursor: pointer;
  transition: all 0.18s ease;
  border: 1px solid var(--border-color);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--reef-gradient);
  color: #ffffff;
  border-color: transparent;
}

.btn-primary:hover {
  filter: brightness(1.08);
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--bg-card-sub);
  color: var(--text-main);
}

.btn-secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
}

.btn-ghost:hover {
  background: var(--bg-card-sub);
  color: var(--text-main);
}

.btn-danger-ghost:hover {
  border-color: var(--danger);
  color: var(--danger-text);
  background: var(--danger-bg);
}

.btn-sm {
  min-height: 34px;
  padding: 0.35rem 0.7rem;
  font-size: 0.8rem;
}

/* Presets rápidos */
.presets-bar {
  margin-bottom: 1.15rem;
}

.presets-label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.55rem;
}

.presets-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.btn-preset {
  background: var(--bg-input);
  color: var(--text-secondary);
  min-height: 36px;
  padding: 0.4rem 0.8rem;
  font-size: 0.82rem;
}

.btn-preset:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-preset.is-active {
  background: var(--primary-light);
  border-color: var(--primary);
  color: var(--primary);
}

/* Resumen global del sistema (Volumen neto, salinidad, objetivos) */
.system-summary-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.summary-kpi-box {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 0.85rem 1rem;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.summary-kpi-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

.summary-kpi-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 600;
}

.summary-kpi-value {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
}

.summary-kpi-sub {
  font-size: 0.76rem;
  color: var(--text-muted);
}

.link-toggle-vol {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--primary);
  cursor: pointer;
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* Cajón desplegable de cubicaje neto */
.volume-drawer {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1.15rem;
  margin-bottom: 1.25rem;
}

.volume-drawer[hidden] {
  display: none;
}

.volume-drawer-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.volume-drawer-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  margin: 0;
}

.volume-discounts-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.9rem;
  padding-top: 0.85rem;
  border-top: 1px solid var(--border-color);
}

.discount-chip {
  font-size: 0.78rem;
  background: var(--bg-card-sub);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.3rem 0.65rem;
  color: var(--text-secondary);
}

/* Navegación de pestañas */
.tabs-nav {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.45rem;
  background: var(--bg-input);
  padding: 0.4rem;
  border-radius: 12px;
  border: 1px solid var(--border-color);
  margin-bottom: 1.5rem;
}

.tab-btn {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-muted);
  border-radius: 9px;
  padding: 0.65rem 0.5rem;
  min-height: 44px;
  font-size: 0.84rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  transition: all 0.18s ease;
  text-align: center;
}

.tab-btn svg {
  width: 17px;
  height: 17px;
  stroke: currentColor;
  flex-shrink: 0;
}

.tab-btn:hover {
  color: var(--text-main);
  background: var(--bg-card-sub);
}

.tab-btn.is-active {
  background: var(--reef-gradient);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(2, 132, 199, 0.25);
}

.tab-panel {
  display: none;
}

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

/* Encabezado de panel y subcontroles */
.panel-header {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 0.85rem;
  margin-bottom: 1.25rem;
}

.panel-title {
  font-size: 1.22rem;
  font-weight: 700;
  margin: 0 0 0.2rem 0;
  color: var(--text-main);
}

.panel-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin: 0;
}

.segmented-control {
  display: inline-flex;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 0.25rem;
  gap: 0.25rem;
  flex-wrap: wrap;
}

.seg-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  padding: 0.45rem 0.85rem;
  min-height: 36px;
  border-radius: 7px;
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
}

.seg-btn.is-active {
  background: var(--primary-light);
  color: var(--primary);
}

/* Cuadrículas y formularios */
.form-grid-4 {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.85rem;
}

.form-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

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

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  min-width: 0;
}

.form-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.4rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.form-hint {
  font-size: 0.76rem;
  color: var(--text-muted);
  line-height: 1.4;
}

.input-wrapper {
  display: flex;
  align-items: stretch;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 9px;
  overflow: hidden;
  transition: border-color 0.18s ease, box-shadow 0.18s ease;
  min-height: 42px;
}

.input-wrapper:focus-within {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.form-input {
  flex: 1 1 0%;
  width: 0;
  min-width: 0;
  background: transparent;
  border: none;
  padding: 0.55rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-main);
  outline: none;
}

.form-input-plain {
  width: 100%;
  min-width: 0;
  min-height: 42px;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 9px;
  padding: 0.55rem 0.75rem;
  font-family: var(--font-main);
  font-size: 0.9rem;
  color: var(--text-main);
  outline: none;
}

.form-input-plain:focus {
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.input-suffix {
  display: inline-flex;
  align-items: center;
  padding: 0 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--bg-card-sub);
  border-left: 1px solid var(--border-color);
  white-space: nowrap;
}

/* Reglas canónicas estrictas para <select> en claro y oscuro */
.form-select {
  appearance: none;
  -webkit-appearance: none;
  width: 100%;
  max-width: 100%;
  min-width: 0;
  min-height: 42px;
  padding: 0.55rem 40px 0.55rem 0.8rem;
  border-radius: 9px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-input);
  background-image: var(--select-arrow);
  background-repeat: no-repeat;
  background-position: right 12px center;
  color: var(--text-main);
  font-family: var(--font-main);
  font-size: 0.88rem;
  font-weight: 500;
  text-overflow: ellipsis;
  white-space: nowrap;
  overflow: hidden;
  cursor: pointer;
}

.form-select:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.form-select option {
  background-color: var(--bg-card);
  color: var(--text-main);
}

.form-textarea {
  width: 100%;
  min-height: 145px;
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.83rem;
  color: var(--text-main);
  resize: vertical;
}

.form-textarea:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.range-slider {
  width: 100%;
  accent-color: var(--primary);
  cursor: pointer;
}

/* Sub-tarjetas de elementos y resultados */
.sub-card {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 13px;
  padding: 1.15rem;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.sub-card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  padding-bottom: 0.65rem;
  border-bottom: 1px solid var(--border-color);
}

.sub-card-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.dot-kh { width: 10px; height: 10px; border-radius: 50%; background: #38bdf8; display: inline-block; }
.dot-ca { width: 10px; height: 10px; border-radius: 50%; background: #14b8a6; display: inline-block; }
.dot-mg { width: 10px; height: 10px; border-radius: 50%; background: #a855f7; display: inline-block; }

/* Alertas y badges de estado */
.alert-banner {
  border-radius: 10px;
  padding: 0.85rem 1rem;
  font-size: 0.86rem;
  line-height: 1.5;
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
  border: 1px solid var(--border-color);
  margin-bottom: 1rem;
}

.alert-banner svg {
  flex-shrink: 0;
  margin-top: 2px;
}

.state-optimal, .status-ok {
  background: var(--success-bg);
  color: var(--success-text);
  border-color: var(--success-border);
}

.state-warning, .status-warning {
  background: var(--warning-bg);
  color: var(--warning-text);
  border-color: var(--warning-border);
}

.state-danger, .status-danger {
  background: var(--danger-bg);
  color: var(--danger-text);
  border-color: var(--danger-border);
}

.state-info {
  background: var(--info-bg);
  color: var(--info-text);
  border-color: var(--info-border);
}

.badge-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.22rem 0.6rem;
  border-radius: 999px;
  border: 1px solid transparent;
}

/* Bloque de dosis calculada */
.dose-output-box {
  background: var(--bg-card-sub);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 0.9rem;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.dose-main-num {
  font-family: var(--font-mono);
  font-size: 1.45rem;
  font-weight: 800;
  color: var(--primary);
  line-height: 1.2;
}

.dose-sub-line {
  font-size: 0.82rem;
  color: var(--text-secondary);
}

.dose-warn-line {
  font-size: 0.79rem;
  color: var(--warning-text);
  background: var(--warning-bg);
  border: 1px solid var(--warning-border);
  border-radius: 8px;
  padding: 0.45rem 0.65rem;
  margin-top: 0.25rem;
}

.section-divider {
  margin: 1.5rem 0 1.25rem;
  padding-top: 1.35rem;
  border-top: 1px solid var(--border-color);
}

/* Conversor de salinidad */
.salinity-outputs-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.7rem;
  margin-top: 1rem;
}

.sal-kpi {
  background: var(--bg-card-sub);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 0.75rem;
  text-align: center;
  min-width: 0;
}

.sal-kpi-name {
  font-size: 0.74rem;
  color: var(--text-muted);
  display: block;
  margin-bottom: 0.25rem;
}

.sal-kpi-val {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
}

/* Gráfica SVG e historial */
.svg-chart-wrap {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1rem;
  margin-top: 1rem;
  overflow: hidden;
}

.chart-controls-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.65rem;
  margin-bottom: 0.75rem;
}

.chart-svg {
  width: 100%;
  height: auto;
  display: block;
}

.chart-stats-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-top: 0.7rem;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Tablas responsivas */
.table-scroll-wrap {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--border-color);
  border-radius: 10px;
  background: var(--bg-input);
  margin-top: 0.85rem;
  -webkit-overflow-scrolling: touch;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.84rem;
  text-align: left;
  min-width: 580px;
}

.data-table th,
.data-table td {
  padding: 0.65rem 0.8rem;
  border-bottom: 1px solid var(--border-color);
  vertical-align: middle;
}

.data-table th {
  background: var(--bg-card-sub);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.8rem;
  color: var(--text-secondary);
  white-space: nowrap;
}

.data-table tr:last-child td {
  border-bottom: none;
}

.delta-up { color: var(--success-text); font-size: 0.73rem; display: block; }
.delta-down { color: var(--warning-text); font-size: 0.73rem; display: block; }

/* Agenda de mantenimiento */
.task-list {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  margin-top: 1rem;
}

.task-item {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 11px;
  padding: 0.85rem 1rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.task-item-overdue {
  border-color: var(--danger-border);
  background: var(--danger-bg);
}

.task-info {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  min-width: 200px;
  flex: 1 1 220px;
}

.task-title {
  font-weight: 600;
  font-size: 0.93rem;
  color: var(--text-main);
}

.task-meta {
  font-size: 0.79rem;
  color: var(--text-muted);
}

.task-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Redfield barra visual */
.redfield-meter-track {
  height: 12px;
  border-radius: 999px;
  background: linear-gradient(90deg, #ef4444 0%, #f59e0b 18%, #10b981 35%, #10b981 65%, #f59e0b 85%, #ef4444 100%);
  position: relative;
  margin: 0.8rem 0 0.5rem;
}

.redfield-meter-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: #ffffff;
  border: 3px solid #0f172a;
  position: absolute;
  top: 50%;
  transform: translate(-50%, -50%);
  transition: left 0.25s ease;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4);
}

.redfield-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.74rem;
  color: var(--text-muted);
}

/* Modal accesible (sin window.alert/confirm/prompt) */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(9, 13, 22, 0.75);
  backdrop-filter: blur(4px);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  padding: 1rem;
}

.modal-backdrop.is-open {
  display: flex;
}

.modal-card {
  width: 100%;
  max-width: 560px;
  max-height: 88vh;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
  margin: 0;
  font-size: 1.08rem;
  color: var(--text-main);
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
  min-width: 36px;
  min-height: 36px;
}

.modal-body {
  padding: 1.2rem 1.25rem;
  overflow-y: auto;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.modal-footer {
  padding: 0.9rem 1.25rem;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 0.6rem;
}

.report-pre {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 0.95rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  white-space: pre-wrap;
  line-height: 1.55;
  color: var(--text-main);
  margin: 0;
}

/* Toast accesible */
.toast-banner {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  background: var(--bg-card);
  color: var(--text-main);
  border: 1px solid var(--primary);
  border-radius: 10px;
  padding: 0.75rem 1.1rem;
  font-size: 0.86rem;
  font-weight: 600;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
  z-index: 10000;
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

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

/* Fórmulas en la guía SEO */
.formula-box {
  background: var(--bg-input);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 0.85rem 1rem;
  font-size: 0.86rem;
  color: var(--primary);
  margin: 0.85rem 0 1.25rem;
  overflow-x: auto;
}

/* Adaptación tablet y móvil */
@media (max-width: 960px) {
  .tabs-nav {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .tabs-nav .tab-btn:last-child {
    grid-column: span 2;
  }

  .form-grid-3 {
    grid-template-columns: 1fr;
  }

  .form-grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .system-summary-strip {
    grid-template-columns: 1fr;
  }

  .salinity-outputs-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .tool-layout {
    margin: 1rem auto 2rem;
    padding: 0 0.75rem;
  }

  .card-main {
    padding: 1rem;
    border-radius: 14px;
  }

  .form-grid-2,
  .form-grid-4,
  .salinity-outputs-grid {
    grid-template-columns: 1fr;
  }

  .tabs-nav {
    grid-template-columns: 1fr;
  }

  .tabs-nav .tab-btn:last-child {
    grid-column: span 1;
  }

  .tank-actions-group,
  .tank-actions-group .btn-secondary,
  .tank-actions-group .btn-ghost {
    width: 100%;
  }

  .presets-grid .btn-preset {
    flex: 1 1 calc(50% - 0.5rem);
  }

  .btn-primary,
  .btn-secondary,
  .form-select,
  .form-input-plain {
    min-height: 44px;
  }

  .toast-banner {
    left: 0.75rem;
    right: 0.75rem;
    bottom: 0.75rem;
    text-align: center;
  }
}

/* Impresión limpia */
@media print {
  .app-header,
  .tools-ad-banner-section,
  .tool-ad-sidebar,
  .affiliate-showcase-container,
  .seo-guide-section,
  .related-tools-section,
  .fijate-footer,
  .presets-bar,
  .tank-actions-group,
  .tabs-nav,
  .toast-banner {
    display: none !important;
  }

  body {
    background: #ffffff !important;
    color: #0f172a !important;
  }

  .card-main {
    box-shadow: none !important;
    border: 1px solid #cbd5e1 !important;
  }
}