:root {
    --bg-dark: #0f172a;
    --bg-card: #1e293b;
    --bg-panel: #334155;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent: #38bdf8;
    --accent-hover: #0ea5e9;
    --danger: #ef4444;
    --success: #22c55e;
    --border: #334155;
}

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

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-y: auto;
}

.app-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.inventory-sidebar {
    width: 300px;
    background: var(--bg-card);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    position: sticky;
    top: 0;
    height: 100vh;
    z-index: 10;
}

.sidebar-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border);
}

.sidebar-header h2 {
    font-size: 1.2rem;
    color: var(--accent);
    margin-bottom: 1rem;
    font-family: 'Share Tech Mono', monospace;
}

.sidebar-header input {
    width: 100%;
    padding: 0.5rem;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: 4px;
    color: var(--text-primary);
}

.inventory-list {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.molecule-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border);
    padding: 1rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.molecule-card:hover {
    border-color: var(--accent);
    background: rgba(56, 189, 248, 0.05);
    transform: translateX(4px);
    box-shadow: 0 0 15px rgba(56, 189, 248, 0.1);
}

.molecule-card .name {
    display: block;
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.molecule-card .formula {
    display: block;
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-family: 'Share Tech Mono', monospace;
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2rem;
    max-width: 1400px;
    margin: 0 auto;
}

.logo-area {
    padding-bottom: 2rem;
    text-align: center;
}

.logo-area .icon { font-size: 2.5rem; }
.logo-area h1 { 
    font-family: 'Share Tech Mono', monospace; 
    color: var(--accent); 
    font-size: 2.5rem;
    margin: 0.5rem 0;
}

/* Tabs */
.app-tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.tab-btn {
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.2s;
}

.tab-btn:hover {
    border-color: var(--accent);
    color: var(--text-primary);
}

.tab-btn.active {
    background: var(--accent);
    color: #000;
    border-color: var(--accent);
    box-shadow: 0 0 15px rgba(56, 189, 248, 0.4);
}

/* Calculator Card */
.calculator-card {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
    max-width: 900px;
    margin: 0 auto 2rem auto;
}

.input-row {
    display: flex;
    gap: 1rem;
    align-items: flex-end;
    margin-bottom: 2rem;
}

.flex-grow { flex: 1; }

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    padding: 0.75rem;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-primary);
    font-size: 1.1rem;
}

.form-group input:focus {
    outline: none;
    border-color: var(--accent);
}

.input-with-unit {
    display: flex;
    gap: 0.5rem;
}

.input-with-unit select {
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-primary);
    padding: 0.5rem;
    cursor: pointer;
}

.primary-btn {
    padding: 0.75rem 1.5rem;
    background: var(--accent);
    color: #000;
    border: none;
    border-radius: 6px;
    font-weight: 700;
    cursor: pointer;
    font-size: 1rem;
}

.primary-btn:hover { background: var(--accent-hover); }

.secondary-btn {
    padding: 0.6rem 1.2rem;
    background: transparent;
    color: var(--accent);
    border: 1px solid var(--accent);
    border-radius: 6px;
    font-weight: 500;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.2s;
}

.secondary-btn:hover {
    background: rgba(56, 189, 248, 0.1);
    box-shadow: 0 0 10px rgba(56, 189, 248, 0.2);
}

.action-bar {
    display: flex;
    justify-content: flex-end;
    margin-bottom: 1.5rem;
}

.action-bar.centered {
    justify-content: center;
}

.centered-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 1.5rem;
}

/* Reaction Builder */
.reaction-builder-container {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.builder-section {
    flex: 1;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 12px;
    padding: 1rem;
    border: 1px solid var(--border);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.section-header h3 {
    font-size: 1rem;
    color: var(--text-secondary);
    text-transform: uppercase;
}

.add-btn {
    background: transparent;
    border: 1px solid var(--accent);
    color: var(--accent);
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.8rem;
    transition: all 0.2s;
}

.add-btn:hover {
    background: var(--accent);
    color: #000;
}

.builder-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.builder-row {
    display: flex;
    gap: 0.5rem;
}

.builder-row input {
    flex: 1;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    padding: 0.5rem;
    border-radius: 4px;
    color: var(--text-primary);
    font-family: 'Share Tech Mono', monospace;
}

.remove-btn {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--danger);
    color: var(--danger);
    width: 32px;
    height: 32px;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}

.remove-btn:hover {
    background: var(--danger);
    color: #fff;
}

/* Coefficients */
.coeff-input {
    width: 40px;
    background: transparent;
    border: 1px solid transparent;
    border-bottom: 1px solid var(--border);
    color: var(--accent);
    font-family: 'Share Tech Mono', monospace;
    font-size: 1.1rem;
    text-align: center;
    padding: 2px;
    margin-right: 5px;
    transition: all 0.2s;
}

.coeff-input:focus {
    outline: none;
    border-bottom-color: var(--accent);
    background: rgba(56, 189, 248, 0.05);
}

.coeff-input.subtle {
    color: transparent;
}

.coeff-input:focus.subtle, .coeff-input:not(.subtle) {
    color: var(--accent);
}

/* Auditor Badges */
.auditor-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.auditor-badge.balanced {
    background: rgba(34, 197, 94, 0.1);
    color: var(--success);
    border: 1px solid var(--success);
}

.auditor-badge.unbalanced {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
    border: 1px solid var(--danger);
}

.discrepancy-list {
    font-size: 0.8rem;
    color: var(--danger);
    margin-top: 0.5rem;
    list-style: none;
    padding-left: 0;
}

.builder-section.error {
    border-color: var(--danger) !important;
    box-shadow: 0 0 10px rgba(239, 68, 68, 0.2);
}

.builder-arrow {
    font-size: 2.5rem;
    color: var(--accent);
    align-self: center;
    text-shadow: 0 0 10px rgba(56, 189, 248, 0.5);
}

/* Results & Tables */
.results-container {
    margin-top: 2rem;
}

.summary-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-box {
    background: rgba(255, 255, 255, 0.05);
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
}

.stat-box.highlight {
    background: rgba(56, 189, 248, 0.1);
    border: 1px solid rgba(56, 189, 248, 0.3);
}

.stat-box .value {
    display: block;
    font-size: 2rem;
    font-weight: 300;
    color: var(--accent);
}

.stat-box .unit {
    font-size: 1rem;
    color: var(--text-secondary);
}

.composition-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.composition-table th {
    text-align: left;
    padding: 1rem;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border);
}

.composition-table td {
    padding: 0.75rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.input-with-label {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    margin-bottom: 0.25rem;
}

.input-with-label small {
    color: var(--text-secondary);
    min-width: 25px;
}

.sim-edit-input {
    background: rgba(0, 0, 0, 0.3) !important;
    border: 1px solid var(--border) !important;
    color: var(--accent) !important;
    padding: 0.25rem 0.5rem !important;
    width: 90px !important;
    border-radius: 4px;
    text-align: right;
    font-size: 0.9rem;
    font-family: 'Share Tech Mono', monospace;
}

.sim-edit-input:focus {
    border-color: var(--accent) !important;
    outline: none;
    background: rgba(56, 189, 248, 0.1) !important;
}

/* Badges */
.setup-container {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
}

.setup-grid-header {
    display: grid;
    grid-template-columns: 120px 1fr 1fr 150px;
    gap: 1rem;
    padding: 0 0.75rem;
    margin-bottom: 0.5rem;
    font-size: 0.8rem;
    text-transform: uppercase;
    color: var(--text-secondary);
    font-weight: 700;
}

.reactant-row {
    display: grid;
    grid-template-columns: 120px 1fr 1fr 150px;
    gap: 1rem;
    align-items: center;
    margin-bottom: 0.5rem;
    background: rgba(255, 255, 255, 0.03);
    padding: 0.5rem 0.75rem;
    border-radius: 8px;
    border: 1px solid transparent;
    transition: all 0.2s;
}

.reactant-status {
    font-size: 0.75rem;
    font-weight: 500;
}

.status-limiting { color: var(--danger); }
.status-excess { color: var(--success); }
.status-required { color: var(--accent); opacity: 0.8; }

.reactant-row:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--border);
}

.reactant-row.product-row .formula {
    color: var(--success);
}

.reactant-row .formula {
    font-family: 'Share Tech Mono', monospace;
    font-weight: 700;
    color: var(--accent);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.reactant-row input {
    background: var(--bg-dark);
    border: 1px solid var(--border);
    padding: 0.5rem;
    border-radius: 4px;
    color: var(--text-primary);
    width: 100%;
    font-family: 'Share Tech Mono', monospace;
    font-size: 1rem;
}

.reactant-row input:focus {
    border-color: var(--accent);
    outline: none;
    background: rgba(56, 189, 248, 0.05);
}

.reactant-row input::placeholder {
    color: rgba(255, 255, 255, 0.1);
}

/* Badges */
.badge-limiting { background: var(--danger); color: #fff; padding: 2px 6px; border-radius: 4px; font-size: 0.7rem; text-transform: uppercase; font-weight: 700; }
.badge-excess { background: var(--success); color: #fff; padding: 2px 6px; border-radius: 4px; font-size: 0.7rem; text-transform: uppercase; font-weight: 700; }

/* Periodic Table */
.periodic-section-container {
    margin-top: 3rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
}

.periodic-table-wrapper {
    width: 100%;
    overflow-x: auto;
    text-align: center;
}

.periodic-grid {
    display: grid;
    grid-template-columns: repeat(18, minmax(40px, 1fr));
    grid-template-rows: repeat(10, minmax(40px, 1fr)); 
    gap: 4px;
    padding: 1rem;
    min-width: 800px;
    max-width: 1100px;
    margin: 0 auto;
}

.element-btn {
    aspect-ratio: 1;
    background: var(--bg-card);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 4px;
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    position: relative;
    transition: all 0.2s;
}

.element-btn:hover {
    transform: scale(1.5);
    z-index: 50;
    box-shadow: 0 0 10px rgba(0,0,0,0.5);
    border-color: var(--text-primary);
}

.element-btn small { position: absolute; top: 2px; left: 2px; font-size: 0.5rem; opacity: 0.7; }
.element-btn strong { font-weight: 700; font-size: 0.85rem; margin-top: 4px; }

.block-s { background-color: rgba(239, 68, 68, 0.2); border-color: rgba(239, 68, 68, 0.4); }
.block-p { background-color: rgba(234, 179, 8, 0.2); border-color: rgba(234, 179, 8, 0.4); }
.block-d { background-color: rgba(59, 130, 246, 0.2); border-color: rgba(59, 130, 246, 0.4); }
.block-f { background-color: rgba(34, 197, 94, 0.2); border-color: rgba(34, 197, 94, 0.4); }

/* Details Panel */
.panel {
    width: 350px;
    background: #1e293b;
    border-radius: 16px;
    padding: 2rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.7);
    z-index: 100;
    border: 1px solid rgba(255, 255, 255, 0.1);
    position: fixed;
    right: 2rem;
    top: 50%;
    transform: translateY(-50%);
}

.glow-s { border-color: rgba(239, 68, 68, 0.5); box-shadow: 0 0 20px rgba(239, 68, 68, 0.2), 0 25px 50px -12px rgba(0, 0, 0, 0.7); }
.glow-p { border-color: rgba(234, 179, 8, 0.5); box-shadow: 0 0 20px rgba(234, 179, 8, 0.2), 0 25px 50px -12px rgba(0, 0, 0, 0.7); }
.glow-d { border-color: rgba(59, 130, 246, 0.5); box-shadow: 0 0 20px rgba(59, 130, 246, 0.2), 0 25px 50px -12px rgba(0, 0, 0, 0.7); }
.glow-f { border-color: rgba(34, 197, 94, 0.5); box-shadow: 0 0 20px rgba(34, 197, 94, 0.2), 0 25px 50px -12px rgba(0, 0, 0, 0.7); }

/* Modal Overlay */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
}

.modal-container {
    background: var(--bg-card);
    width: 90%;
    max-width: 600px;
    border-radius: 16px;
    border: 1px solid var(--border);
    box-shadow: 0 0 30px rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    max-height: 80vh;
}

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 { color: var(--accent); font-family: 'Share Tech Mono', monospace; }

.modal-body {
    padding: 1.5rem;
    overflow-y: auto;
}

.picker-search { margin-bottom: 1.5rem; }
.picker-search input {
    width: 100%;
    padding: 0.75rem;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-primary);
}

.picker-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.picker-chip {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border);
    padding: 0.75rem;
    border-radius: 8px;
    cursor: pointer;
    text-align: center;
    transition: all 0.2s;
}

.picker-chip:hover {
    border-color: var(--accent);
    background: rgba(56, 189, 248, 0.05);
}

.picker-chip .name { display: block; font-weight: 700; font-size: 0.8rem; }
.picker-chip .formula { font-size: 0.7rem; color: var(--text-secondary); }

.modal-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--border);
    text-align: center;
}

.close-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 1.5rem;
    cursor: pointer;
}

.hidden { display: none !important; }

.hint { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 1rem; }

.error-banner {
    background: rgba(239, 68, 68, 0.2);
    color: #fca5a5;
    padding: 1rem;
    border-radius: 6px;
    margin-top: 1rem;
    border: 1px solid var(--danger);
}