:root {
    --nux-bg: #080e14;           
    --nux-card-bg: #0d1520;      
    --nux-cyan: #06b6d4;         
    --nux-green: #10b981;        
    --text-white: #ffffff;       
    --text-muted: #8fa0b5;       
    --border-color: #1e293b;     
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--nux-bg);
    color: var(--text-white);
    padding: 10px 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 100vh;
}

.header { text-align: center; margin-bottom: 15px; max-width: 900px; }
.logo { margin-bottom: 5px; }
.logo-img { max-width: 260px; height: auto; display: block; margin: 0 auto; }
.header h1 { font-size: 1.5rem; color: var(--text-white); margin-bottom: 8px; font-weight: 700; }
.header p { color: var(--text-muted); font-size: 0.95rem; line-height: 1.5; }

.main-wrapper { max-width: 1300px; width: 100%; display: flex; flex-direction: column; gap: 25px; }

/* Grid Superior de 3 Columnas */
.calculator-grid-top {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
}

.column-card {
    background: var(--nux-card-bg);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 25px;
    display: flex;
    flex-direction: column;
}

.column-card h2 {
    font-size: 0.95rem;
    color: var(--nux-cyan);
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.inputs-grid, .modules-grid { display: flex; flex-direction: column; gap: 14px; }
.input-group { display: flex; flex-direction: column; gap: 5px; }
.input-group label { font-size: 0.85rem; font-weight: 600; }
.input-wrapper input {
    width: 100%; padding: 10px 12px; font-size: 0.95rem; font-family: inherit;
    border: 1px solid var(--border-color); border-radius: 8px; background: #080e14; color: var(--text-white); outline: none;
}
.input-wrapper input:focus { border-color: var(--nux-cyan); }

.retention-group { margin-bottom: 16px; background: #080e14; padding: 12px; border-radius: 8px; border: 1px solid var(--border-color); }
.retention-label { display: block; font-size: 0.8rem; font-weight: 700; margin-bottom: 6px; }
.retention-dropdown {
    width: 100%; padding: 10px; border-radius: 6px; border: 1px solid var(--border-color);
    font-family: inherit; font-size: 0.9rem; background: var(--nux-card-bg); color: var(--text-white); cursor: pointer; outline: none;
}

.checkbox-card { display: flex; align-items: start; gap: 12px; background: #080e14; padding: 14px; border-radius: 10px; border: 1px solid var(--border-color); cursor: pointer; }
.checkbox-card:hover:not(.disabled) { border-color: var(--nux-cyan); background: #0c1a24; }
.checkbox-card.disabled { cursor: not-allowed; opacity: 0.4; }
.checkbox-card input[type="checkbox"] { width: 18px; height: 18px; margin-top: 2px; accent-color: var(--nux-cyan); }
.checkbox-info label { display: block; font-weight: 600; font-size: 0.9rem; }
.checkbox-info p { font-size: 0.76rem; color: var(--text-muted); margin-top: 4px; line-height: 1.4; }

/* DISEÑO INFERIOR HORIZONTAL COMPACTO */
.calculator-bottom-row {
    display: flex;
    flex-direction: column;
    gap: 15px;
    background: var(--nux-card-bg);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 30px;
}

.plan-horizontal-card {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 30px;
}

.plan-horizontal-card.active { border-left: 4px solid var(--nux-green); padding-left: 15px; }

.plan-main-info { flex: 2; }
.plan-title-text { font-size: 1.4rem; font-weight: 700; color: var(--text-white); margin-bottom: 6px; }
.plan-desc-text { font-size: 0.88rem; color: var(--text-muted); line-height: 1.5; }

.plan-price-metrics {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 10px;
    text-align: right;
}

.plan-cost-display { font-size: 2.2rem; font-weight: 700; color: var(--nux-green); }

.client-metrics-box { font-size: 0.82rem; color: var(--text-white); display: flex; flex-direction: column; gap: 4px; }
.client-metrics-box span { color: var(--nux-cyan); font-weight: 600; }

.tax-note { font-size: 0.75rem; color: var(--text-muted); border-top: 1px solid var(--border-color); padding-top: 10px; font-style: italic; line-height: 1.4; }

.btn-submit {
    display: block; text-align: center; background: linear-gradient(135deg, #0a3a40, #0c4d37);
    border: 1px solid var(--nux-green); color: var(--text-white); padding: 14px; border-radius: 8px;
    font-weight: 600; font-size: 1rem; width: 100%; cursor: pointer; transition: all 0.2s; margin-top: 5px;
}
.btn-submit:hover { background: linear-gradient(135deg, #0e525a, #11684b); box-shadow: 0 0 15px rgba(16, 185, 129, 0.2); }

@media (max-width: 992px) {
    .calculator-grid-top { grid-template-columns: 1fr; }
    .plan-horizontal-card { flex-direction: column; align-items: flex-start; text-align: left; }
    .plan-price-metrics { align-items: flex-start; text-align: left; width: 100%; }
}