/* ===== 4-Column Layout: Controls | Results | Params | Charts ===== */
.sim-layout {
    display: grid;
    grid-template-columns: 260px 300px 280px 280px 1fr;
    min-height: 100vh;
    padding-top: 65px;
    position: relative;
    z-index: 1;
}

/* ===== Shared Column Style ===== */
.sim-col {
    position: sticky;
    top: 65px;
    height: calc(100vh - 65px);
    overflow-y: auto;
    padding: 0.75rem;
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.sim-col::-webkit-scrollbar { width: 3px; }
.sim-col::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 2px; }

.col-title {
    font-family: var(--font-display);
    font-size: 0.58rem;
    letter-spacing: 2px;
    color: var(--accent-blue);
    text-transform: uppercase;
    padding-bottom: 0.4rem;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 0.25rem;
}

/* ===== Col 1: Controls ===== */
.sim-panel {
    position: sticky;
    top: 65px;
    height: calc(100vh - 65px);
    overflow-y: auto;
    padding: 1rem;
    background: rgba(17, 24, 39, 0.85);
    backdrop-filter: blur(20px);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.sim-panel::-webkit-scrollbar { width: 3px; }
.sim-panel::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 2px; }

.panel-header h2 { font-family: var(--font-display); font-size: 0.9rem; font-weight: 700; letter-spacing: 1px; margin-bottom: 0.15rem; display: flex; align-items: center; gap: 0.4rem; }

.beta-badge {
    font-size: 0.45rem;
    font-weight: 700;
    letter-spacing: 1.5px;
    padding: 0.15rem 0.4rem;
    background: rgba(168, 85, 247, 0.15);
    color: #a855f7;
    border: 1px solid rgba(168, 85, 247, 0.3);
    border-radius: 4px;
}
.panel-header p { font-size: 0.65rem; color: var(--text-muted); }

.control-group { display: flex; flex-direction: column; gap: 0.4rem; }
.control-label { font-family: var(--font-display); font-size: 0.55rem; letter-spacing: 2px; color: var(--text-secondary); text-transform: uppercase; }

.drug-cards { display: flex; flex-direction: column; gap: 0.25rem; }
.drug-card {
    display: flex; justify-content: space-between; align-items: center;
    padding: 0.4rem 0.6rem; background: rgba(255,255,255,0.03);
    border: 1px solid var(--border-color); border-radius: 7px;
    cursor: pointer; transition: all 0.2s; color: var(--text-secondary); font-family: var(--font-body);
}
.drug-card:hover { background: rgba(255,255,255,0.06); }
.drug-card.selected { background: rgba(79,172,254,0.08); border-color: rgba(79,172,254,0.3); color: var(--text-primary); }
.drug-name { font-size: 0.75rem; font-weight: 500; }
.drug-dose { font-family: var(--font-display); font-size: 0.55rem; color: var(--text-muted); }

.input-row { display: flex; align-items: center; gap: 0.5rem; }
.slider { flex: 1; -webkit-appearance: none; height: 3px; background: rgba(255,255,255,0.08); border-radius: 2px; outline: none; }
.slider::-webkit-slider-thumb { -webkit-appearance: none; width: 12px; height: 12px; border-radius: 50%; background: var(--accent-blue); cursor: pointer; }
.num-input { width: 70px; padding: 0.25rem 0.4rem; background: rgba(255,255,255,0.05); border: 1px solid var(--border-color); border-radius: 5px; color: var(--text-primary); font-family: var(--font-display); font-size: 0.65rem; text-align: center; outline: none; }
.num-input:focus { border-color: rgba(79,172,254,0.4); }

.btn-run { width: 100%; justify-content: center; padding: 0.65rem; font-family: var(--font-display); font-size: 0.75rem; letter-spacing: 1px; margin-top: auto; }
.spinner { width: 14px; height: 14px; border: 2px solid rgba(255,255,255,0.3); border-top-color: white; border-radius: 50%; animation: spin 0.6s linear infinite; }
.hidden { display: none; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ===== Col 2: PK Results ===== */
#colResults { background: rgba(15, 20, 35, 0.5); }

.pk-card-v {
    background: var(--bg-card); border: 1px solid var(--border-color);
    border-radius: 8px; padding: 0.6rem;
}
.pk-card-v:hover { border-color: rgba(255,255,255,0.08); }

.pk-env-header { display: flex; align-items: center; gap: 0.35rem; margin-bottom: 0.35rem; font-family: var(--font-display); font-size: 0.62rem; font-weight: 600; letter-spacing: 0.5px; }
.pk-env-dot { width: 7px; height: 7px; border-radius: 50%; flex-shrink: 0; }
.earth-dot { background: var(--earth-color); box-shadow: 0 0 5px var(--earth-glow); }
.iss-dot { background: #a855f7; box-shadow: 0 0 5px rgba(168, 85, 247, 0.3); }
.moon-dot { background: var(--moon-color); box-shadow: 0 0 5px var(--moon-glow); }
.mars-dot { background: var(--mars-color); box-shadow: 0 0 5px var(--mars-glow); }

.pk-vals-v { display: flex; flex-direction: column; gap: 0.2rem; }
.pk-row { display: flex; justify-content: space-between; align-items: center; padding: 0.15rem 0; }
.pk-key { font-size: 0.62rem; color: var(--text-muted); }
.pk-num-row { display: flex; align-items: baseline; gap: 0.3rem; }
.pk-num { font-family: var(--font-display); font-size: 0.68rem; font-weight: 600; color: var(--text-primary); }
.pk-delta { font-size: 0.52rem; font-weight: 600; white-space: nowrap; }
.pk-delta.baseline { color: var(--accent-blue); opacity: 0.5; font-size: 0.48rem; letter-spacing: 0.5px; }
.pk-delta.delta-up { color: #f97316; }
.pk-delta.delta-down { color: #34d399; }

/* Dose Guide */
.dose-guide-compact {
    background: var(--bg-card); border: 1px solid var(--border-color);
    border-left: 2px solid var(--accent-blue); border-radius: 8px; padding: 0.6rem;
}
.guide-mini { margin-bottom: 0.4rem; }
.guide-mini-header { display: flex; align-items: center; gap: 0.3rem; font-family: var(--font-display); font-size: 0.55rem; font-weight: 600; margin-bottom: 0.2rem; color: var(--text-secondary); }
.guide-mini-row { display: grid; grid-template-columns: 1fr 1.2fr 0.8fr; gap: 0.2rem; padding: 0.15rem 0; font-size: 0.62rem; align-items: center; }
.guide-criterion { color: var(--text-muted); font-size: 0.58rem; }
.guide-val { color: var(--text-secondary); font-family: var(--font-display); font-size: 0.6rem; }
.guide-dose { color: var(--accent-cyan); font-weight: 700; font-size: 0.65rem; }
.guide-pct { font-weight: 600; font-size: 0.6rem; }
.guide-pct.increase { color: #f97316; }
.guide-pct.decrease { color: #34d399; }

/* ===== Col 3: Parameters ===== */
#colParams { background: rgba(12, 16, 28, 0.5); }

.param-card {
    background: var(--bg-card); border: 1px solid var(--border-color);
    border-radius: 8px; padding: 0.5rem;
}

.param-card-title {
    font-family: var(--font-display); font-size: 0.55rem; font-weight: 600;
    letter-spacing: 0.5px; color: var(--text-secondary);
    margin-bottom: 0.3rem; padding-bottom: 0.25rem;
    border-bottom: 1px solid rgba(255,255,255,0.04);
}

.param-table { display: flex; flex-direction: column; }
.param-row { display: flex; justify-content: space-between; align-items: center; padding: 0.18rem 0; border-bottom: 1px solid rgba(255,255,255,0.02); }
.param-row:last-child { border-bottom: none; }
.param-key { font-size: 0.6rem; color: var(--text-muted); }
.param-val { font-family: var(--font-display); font-size: 0.62rem; font-weight: 500; color: var(--text-primary); }

.param-env-header {
    display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr 1fr; gap: 0.2rem;
    padding: 0.25rem 0; margin-bottom: 0.15rem; border-bottom: 1px solid var(--border-color);
}
.param-env-header span { font-family: var(--font-display); font-size: 0.5rem; letter-spacing: 0.5px; color: var(--text-muted); text-align: right; }
.param-env-header span:first-child { text-align: left; }

.param-env-row {
    display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr 1fr; gap: 0.2rem;
    padding: 0.18rem 0; border-bottom: 1px solid rgba(255,255,255,0.02);
}
.param-env-row:last-child { border-bottom: none; }
.param-env-row .param-key { font-size: 0.58rem; }
.param-env-val { font-family: var(--font-display); font-size: 0.58rem; color: var(--text-secondary); text-align: right; }
.param-env-val.changed { color: #f97316; }

#colEquations { background: rgba(13, 18, 32, 0.5); }

/* ===== PBPK Equations ===== */
.eq-section {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.eq-toggle {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0.6rem;
    cursor: pointer;
    list-style: none;
}

.eq-toggle::-webkit-details-marker { display: none; }

.eq-arrow {
    font-size: 0.55rem;
    color: var(--text-muted);
    transition: transform 0.2s;
}

details[open] .eq-arrow { transform: rotate(90deg); }

.eq-content {
    padding: 0.4rem 0.6rem 0.6rem;
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.eq-group {
    padding: 0.35rem 0;
    border-bottom: 1px solid rgba(255,255,255,0.03);
}

.eq-group:last-of-type { border-bottom: none; }

.eq-label {
    font-family: var(--font-display);
    font-size: 0.55rem;
    font-weight: 600;
    color: var(--accent-blue);
    letter-spacing: 0.3px;
    margin-bottom: 0.25rem;
}

.eq-note { font-weight: 400; color: var(--text-muted); font-size: 0.5rem; }

.eq-formula {
    font-size: 0.6rem;
    color: var(--text-secondary);
    line-height: 1.6;
    padding-left: 0.4rem;
    word-break: break-word;
}

.eq-list {
    display: flex;
    flex-direction: column;
}

.eq-row {
    padding: 0.3rem 0;
    border-bottom: 1px solid rgba(255,255,255,0.03);
}

.eq-row:last-child { border-bottom: none; }

.eq-organ {
    display: block;
    font-family: var(--font-display);
    font-size: 0.5rem;
    font-weight: 600;
    color: var(--accent-blue);
    letter-spacing: 0.3px;
    margin-bottom: 0.15rem;
}

.eq-lhs { color: var(--text-primary); font-weight: 600; }
.eq-formula sub { font-size: 0.48rem; }

.eq-legend {
    margin-top: 0.3rem;
    padding-top: 0.4rem;
    border-top: 1px solid var(--border-color);
}

.eq-legend-title {
    font-family: var(--font-display);
    font-size: 0.5rem;
    color: var(--text-muted);
    letter-spacing: 1px;
    margin-bottom: 0.3rem;
    text-transform: uppercase;
}

.eq-legend-item {
    font-size: 0.55rem;
    color: var(--text-muted);
    line-height: 1.6;
    padding-left: 0.3rem;
}

.eq-legend-item span {
    color: var(--text-secondary);
    font-weight: 600;
    display: inline-block;
    min-width: 2.5rem;
}

.eq-legend-item sub { font-size: 0.45rem; }

/* ===== Col 4: Charts (single column stack) ===== */
.sim-charts-col {
    border-right: none;
    background: rgba(10, 14, 24, 0.3);
}

#chartsGrid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(400px, 1fr));
    gap: 0.5rem;
}

.chart-card {
    background: var(--bg-card); border: 1px solid var(--border-color);
    border-radius: 8px; padding: 0.4rem;
}

.chart-wrap {
    position: relative;
    width: 100%;
    aspect-ratio: 5 / 3;
}

.col-title-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 0.4rem;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 0.25rem;
}

.scale-toggle {
    display: flex;
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    overflow: hidden;
}

.scale-btn {
    padding: 0.25rem 0.6rem;
    background: none;
    border: none;
    color: var(--text-muted);
    font-family: var(--font-display);
    font-size: 0.55rem;
    letter-spacing: 0.5px;
    cursor: pointer;
    transition: all 0.2s;
}

.scale-btn:hover { color: var(--text-secondary); }
.scale-btn.active { background: rgba(79,172,254,0.15); color: var(--accent-blue); }

.sim-disclaimer {
    text-align: center;
    font-family: var(--font-display);
    font-size: 0.52rem;
    font-weight: 400;
    letter-spacing: 0.5px;
    color: var(--text-muted);
    line-height: 1.8;
    margin-top: auto;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border-color);
}

.sim-disclaimer + .btn-run { margin-top: 0.5rem; }

.chart-placeholder {
    display: flex; align-items: center; justify-content: center;
    min-height: 200px; color: var(--text-muted); font-size: 0.75rem;
}

/* ===== Responsive ===== */
@media (max-width: 1200px) {
    .sim-layout { grid-template-columns: 200px 1fr 1fr; }
    .sim-panel { grid-row: 1 / -1; }
    #colParams { border-right: none; }
    .sim-charts-col { grid-column: 2 / -1; }
}

@media (max-width: 768px) {
    .sim-layout { grid-template-columns: 1fr; }
    .sim-panel, .sim-col { position: static; height: auto; border-right: none; border-bottom: 1px solid var(--border-color); }
}