:root {
    --bg-dark: #2c3e50;
    --bg-sidebar: #1e272e;
    --border-color: #3d4f5d;
    --workspace-bg: #f8f9fa;
    --text-light: #f5f6fa;
    --text-muted: #a4b0be;
    --primary: #3498db;
    --primary-hover: #2980b9;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    
    /* PSE Category Colors */
    --color-alkalimetall: #ff7675;
    --color-erdalkali: #e17055;
    --color-uebergang: #b2bec3;
    --color-metalloid: #fdcb6e;
    --color-nichtmetall: #74b9ff;
    --color-halogen: #55efc4;
    --color-edelgas: #e84393;
    --color-metall: #ffeaa7;
}

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

body {
    display: flex;
    height: 100vh;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-light);
    overflow: hidden;
}

/* Sidebar Layout */
#sidebar {
    width: 320px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    height: 100%;
}

.sidebar-header {
    padding: 20px;
    padding-bottom: 12px;
}

.sidebar-header h2 {
    font-size: 1.5rem;
    margin-bottom: 5px;
    color: #fff;
}

.sidebar-header p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* Sidebar Mode Tabs */
.sidebar-tabs {
    display: flex;
    background-color: rgba(0,0,0,0.25);
    border-bottom: 1px solid var(--border-color);
    padding: 0 10px;
}

.tab-btn {
    flex: 1;
    background: none;
    border: none;
    color: var(--text-muted);
    font-weight: bold;
    font-size: 0.9rem;
    padding: 12px;
    cursor: pointer;
    transition: color 0.2s;
    position: relative;
}

.tab-btn:hover {
    color: #fff;
}

.tab-btn.active {
    color: var(--primary);
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 10%;
    width: 80%;
    height: 3px;
    background-color: var(--primary);
    border-radius: 3px;
}

.tab-content {
    display: flex;
    flex-direction: column;
    flex-grow: 1;
    overflow-y: auto;
}

/* Elements Selector */
#elements-section, #story-elements-section {
    padding: 20px;
    border-bottom: 1px solid var(--border-color);
}

#elements-section h3, #book-section h3, #story-elements-section h3 {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-muted);
    margin-bottom: 15px;
}

.elements-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
}

.spawn-btn {
    height: 50px;
    width: 50px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    font-size: 1.1rem;
    cursor: pointer;
    user-select: none;
    color: #333;
    border: 2px solid rgba(0,0,0,0.15);
    box-shadow: 0 4px 6px rgba(0,0,0,0.2);
    background-image: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.4) 0%, rgba(0, 0, 0, 0.3) 100%);
    transition: transform 0.1s, box-shadow 0.1s;
}

.spawn-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 6px 10px rgba(0,0,0,0.3);
}

.spawn-btn:active {
    transform: scale(0.95);
}

.spawn-btn[data-element="C"] {
    color: #fff;
}

/* Discovery Book (Lexikon) */
#book-section {
    padding: 20px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.book-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

#discovery-progress {
    background-color: var(--primary);
    padding: 3px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: bold;
}

#discovery-book {
    flex-grow: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding-right: 5px;
}

#discovery-book::-webkit-scrollbar, .tab-content::-webkit-scrollbar {
    width: 6px;
}
#discovery-book::-webkit-scrollbar-track, .tab-content::-webkit-scrollbar-track {
    background: transparent;
}
#discovery-book::-webkit-scrollbar-thumb, .tab-content::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 3px;
}

.book-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 15px;
    background-color: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    font-size: 0.9rem;
    transition: background-color 0.2s, border-color 0.2s;
    user-select: none;
}

.book-item.locked {
    color: var(--text-muted);
    opacity: 0.6;
}

.book-item.unlocked {
    background-color: rgba(52, 152, 219, 0.1);
    border-color: rgba(52, 152, 219, 0.2);
    cursor: pointer;
}

.book-item.unlocked:hover {
    background-color: rgba(52, 152, 219, 0.2);
    border-color: rgba(52, 152, 219, 0.4);
}

.book-formula {
    font-weight: bold;
}

.book-name {
    font-size: 0.85rem;
}

/* ========================================= */
/* STORY MODE DESIGN SPECIFICS */
/* ========================================= */

#story-level-selector {
    padding: 15px 20px;
    background-color: rgba(0,0,0,0.15);
    border-bottom: 1px solid var(--border-color);
}

.level-selector-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.level-selector-header h3 {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-muted);
}

#story-overall-progress {
    background-color: #2ed573;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: bold;
    color: white;
}

.level-dots-grid {
    display: flex;
    gap: 8px;
    justify-content: space-between;
}

.level-dot {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    border: 2px solid var(--border-color);
    background-color: rgba(255, 255, 255, 0.03);
    color: var(--text-muted);
    font-weight: bold;
    font-size: 0.95rem;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: background-color 0.2s, border-color 0.2s, color 0.2s, transform 0.1s;
    user-select: none;
}

.level-dot.locked {
    opacity: 0.35;
    cursor: not-allowed;
}

.level-dot.active {
    border-color: var(--primary);
    background-color: rgba(52, 152, 219, 0.15);
    color: #fff;
    transform: scale(1.05);
    box-shadow: 0 0 10px rgba(52, 152, 219, 0.3);
}

.level-dot.completed {
    border-color: #2ed573;
    background-color: rgba(46, 213, 115, 0.15);
    color: #2ed573;
}

.level-dot:hover:not(.locked) {
    transform: scale(1.1);
}

/* Quest Card and Dialog Bubble */
#story-quest-panel {
    padding: 20px;
    border-bottom: 1px solid var(--border-color);
}

.quest-card {
    background-color: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 15px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.quest-header {
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 8px;
}

#quest-level-title {
    font-weight: bold;
    font-size: 1.05rem;
    color: #ffeaa7;
}

.professor-dialog-box {
    display: flex;
    gap: 12px;
    align-items: flex-start;
}

.professor-avatar {
    font-size: 2.2rem;
    background-color: rgba(0,0,0,0.25);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
    border: 1px solid var(--border-color);
    flex-shrink: 0;
}

.professor-bubble {
    background-color: rgba(0,0,0,0.2);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 10px 12px;
    position: relative;
}

.professor-bubble::before {
    content: '';
    position: absolute;
    left: -6px;
    top: 15px;
    width: 0;
    height: 0;
    border-top: 6px solid transparent;
    border-bottom: 6px solid transparent;
    border-right: 6px solid var(--border-color);
}

.professor-bubble p {
    font-size: 0.8rem;
    line-height: 1.4;
    color: #dfe6e9;
    text-align: left;
}

.quest-objective-box h4 {
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--text-muted);
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.objective-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.85rem;
    font-weight: bold;
    background-color: rgba(0,0,0,0.15);
    padding: 8px;
    border-radius: 6px;
    border: 1px solid rgba(255,255,255,0.02);
}

.objective-checkbox {
    font-size: 0.9rem;
}

.objective-item.completed {
    color: #2ed573;
    text-decoration: line-through;
}

/* Large Avatar in Modal */
.professor-avatarlarge {
    font-size: 3.5rem;
    background-color: rgba(0,0,0,0.15);
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3);
    border: 2px solid var(--border-color);
    margin-bottom: 15px;
}

/* ========================================= */
/* Labor Tisch Layout */
/* ========================================= */

#lab-desk {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    height: 100%;
    background-color: var(--bg-dark);
}

.desk-header {
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.1);
    border-bottom: 1px solid var(--border-color);
}

.desk-header h2 {
    font-size: 1.4rem;
    color: #fff;
}

.desk-header p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.desk-controls {
    display: flex;
    align-items: center;
    gap: 12px;
}

#stats {
    font-size: 0.9rem;
    color: var(--text-muted);
    background-color: rgba(0,0,0,0.2);
    padding: 8px 12px;
    border-radius: 6px;
    border: 1px solid rgba(255,255,255,0.05);
}

.control-btn {
    border: none;
    padding: 8px 15px;
    border-radius: 6px;
    cursor: pointer;
    font-weight: bold;
    font-size: 0.9rem;
    transition: background-color 0.2s, transform 0.1s;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

#pse-toggle-btn {
    background-color: #0984e3;
    color: white;
}
#pse-toggle-btn:hover {
    background-color: #00cec9;
}

.control-btn.danger {
    background-color: #e74c3c;
    color: white;
}
.control-btn.danger:hover {
    background-color: #c0392b;
}

.control-btn:active {
    transform: scale(0.95);
}

/* Workspace Canvas */
#workspace {
    flex-grow: 1;
    background-color: var(--workspace-bg);
    background-image: 
        linear-gradient(rgba(0, 0, 0, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 0, 0, 0.05) 1px, transparent 1px);
    background-size: 30px 30px;
    margin: 20px;
    border-radius: 12px;
    position: relative;
    overflow: hidden;
    box-shadow: inset 0 2px 10px rgba(0, 0, 0, 0.15);
    border: 1px solid var(--border-color);
}

/* Atoms and Molecules inside workspace */
.atom {
    width: 55px;
    height: 55px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    font-weight: bold;
    font-size: 1.15rem;
    cursor: grab;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3);
    user-select: none;
    border: 2px solid rgba(0,0,0,0.2);
    background-image: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.4) 0%, rgba(0, 0, 0, 0.45) 100%);
    transition: transform 0.1s;
}

.atom:active {
    cursor: grabbing;
    transform: scale(1.05);
}

.molecule {
    padding: 12px 24px;
    border-radius: 30px;
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    font-weight: bold;
    font-size: 1.05rem;
    cursor: grab;
    box-shadow: 0 5px 12px rgba(0,0,0,0.3);
    color: white;
    user-select: none;
    border: 2px solid rgba(0,0,0,0.25);
    background-image: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, rgba(0,0,0,0.2) 100%);
    transition: transform 0.1s;
    text-shadow: 0 1px 2px rgba(0,0,0,0.5);
}

.molecule:active {
    cursor: grabbing;
    transform: scale(1.05);
}

/* Particle Explosion Sparks */
.particle {
    position: absolute;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    pointer-events: none;
    z-index: 100;
}

/* Modals */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    transition: opacity 0.3s ease;
}

.modal.hidden {
    opacity: 0;
    pointer-events: none;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(5px);
}

.modal-content {
    position: relative;
    background-color: #2c3e50;
    border: 2px solid var(--border-color);
    border-radius: 16px;
    width: 450px;
    max-width: 90%;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    overflow: hidden;
    transform: scale(0.8);
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    color: white;
}

.modal:not(.hidden) .modal-content {
    transform: scale(1);
}

.modal-header {
    background-color: rgba(0, 0, 0, 0.2);
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--border-color);
}

.modal-close-icon {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.8rem;
    cursor: pointer;
    transition: color 0.2s;
}

.modal-close-icon:hover {
    color: #e74c3c;
}

.modal-emoji {
    font-size: 2rem;
    margin-right: 10px;
}

.modal-header h2 {
    font-size: 1.3rem;
    flex-grow: 1;
}

.modal-body {
    padding: 30px 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

#modal-formula-badge {
    background-color: var(--primary);
    font-weight: bold;
    font-size: 1.8rem;
    padding: 10px 25px;
    border-radius: 50px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3);
    margin-bottom: 15px;
    border: 2px solid rgba(255,255,255,0.1);
}

#modal-molecule-name {
    font-size: 1.4rem;
    margin-bottom: 20px;
    color: #ffeaa7;
}

#modal-description {
    font-size: 0.95rem;
    line-height: 1.5;
    color: #dfe6e9;
}

.modal-footer {
    padding: 15px 20px;
    background-color: rgba(0, 0, 0, 0.1);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: center;
}

#modal-close-btn, #story-next-level-btn {
    background-color: #2ed573;
    color: white;
    border: none;
    padding: 10px 30px;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    box-shadow: 0 4px 6px rgba(0,0,0,0.2);
}

#modal-close-btn:hover, #story-next-level-btn:hover {
    background-color: #26af5a;
}

#modal-close-btn:active, #story-next-level-btn:active {
    transform: scale(0.95);
}

/* ========================================= */
/* INTERAKTIVES PERIODENSYSTEM (PSE) STYLES */
/* ========================================= */

.pse-modal-content {
    width: 1100px;
    max-width: 95%;
    height: 650px;
    display: flex;
    flex-direction: column;
}

.pse-modal-body {
    flex-grow: 1;
    display: flex;
    padding: 20px;
    gap: 20px;
    overflow: hidden;
}

/* Linke Spalte - PSE Gitter */
.pse-grid-container {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

#pse-grid {
    display: grid;
    grid-template-columns: repeat(18, 1fr);
    grid-template-rows: repeat(7, 1fr);
    gap: 6px;
    padding: 10px;
    background-color: rgba(0, 0, 0, 0.15);
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

/* Einzelnes Element-Kästchen im PSE */
.pse-el {
    aspect-ratio: 1;
    border-radius: 6px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 4px;
    font-size: 0.65rem;
    user-select: none;
    cursor: default;
    transition: transform 0.15s, box-shadow 0.15s, border-color 0.15s;
    box-shadow: 0 2px 4px rgba(0,0,0,0.15);
}

.pse-el.active-el {
    cursor: pointer;
    border: 2px solid transparent;
}

.pse-el.active-el:hover {
    transform: scale(1.15);
    z-index: 10;
    box-shadow: 0 5px 15px rgba(0,0,0,0.4);
}

.pse-el.locked-el {
    opacity: 0.15;
    background-color: rgba(255, 255, 255, 0.02);
}

.pse-el.locked-el:hover {
    opacity: 0.3;
}

.pse-el-number {
    font-size: 0.55rem;
    color: var(--text-muted);
}

.pse-el-symbol {
    font-size: 1.1rem;
    font-weight: bold;
    text-align: center;
    line-height: 1;
}

.pse-el-name {
    font-size: 0.5rem;
    text-align: center;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-muted);
}

.pse-el.active-el .pse-el-name,
.pse-el.active-el .pse-el-number {
    color: #333;
}
.pse-el.active-el[data-symbol="C"] .pse-el-name,
.pse-el.active-el[data-symbol="C"] .pse-el-number {
    color: var(--text-muted);
}

/* Category Color Highlights for active elements */
.alkalimetall { background-color: var(--color-alkalimetall); color: #333; border-color: rgba(0,0,0,0.15); }
.erdalkali { background-color: var(--color-erdalkali); color: #333; border-color: rgba(0,0,0,0.15); }
.uebergang { background-color: var(--color-uebergang); color: #333; border-color: rgba(0,0,0,0.15); }
.metalloid { background-color: var(--color-metalloid); color: #333; border-color: rgba(0,0,0,0.15); }
.nichtmetall { background-color: var(--color-nichtmetall); color: #333; border-color: rgba(0,0,0,0.15); }
.halogen { background-color: var(--color-halogen); color: #333; border-color: rgba(0,0,0,0.15); }
.edelgas { background-color: var(--color-edelgas); color: #333; border-color: rgba(0,0,0,0.15); }
.metall { background-color: var(--color-metall); color: #333; border-color: rgba(0,0,0,0.15); }

.pse-el.active-el[data-symbol="C"] {
    color: #fff;
}

/* Legend */
.pse-legend {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    padding: 10px;
    font-size: 0.75rem;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-muted);
}

.legend-color {
    width: 12px;
    height: 12px;
    border-radius: 3px;
    display: inline-block;
}

/* Rechte Spalte: Steckbrief */
#pse-steckbrief {
    width: 320px;
    background-color: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    overflow-y: auto;
}

.steckbrief-empty {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.5;
}

.steckbrief-card {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.steckbrief-header {
    display: flex;
    align-items: center;
    gap: 15px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 12px;
}

#steckbrief-box {
    width: 55px;
    height: 55px;
    border-radius: 8px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    font-size: 1.6rem;
    color: #333;
    box-shadow: 0 4px 6px rgba(0,0,0,0.3);
}

#steckbrief-name {
    font-size: 1.25rem;
    color: #fff;
}

#steckbrief-category {
    font-size: 0.75rem;
    color: #ffeaa7;
    background-color: rgba(255, 234, 167, 0.1);
    padding: 2px 8px;
    border-radius: 20px;
    border: 1px solid rgba(255, 234, 167, 0.2);
}

.steckbrief-stats {
    display: flex;
    gap: 12px;
}

.steckbrief-stat-box {
    flex: 1;
    background-color: rgba(0, 0, 0, 0.15);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 8px;
    text-align: center;
}

.stat-label {
    font-size: 0.65rem;
    color: var(--text-muted);
    text-transform: uppercase;
    display: block;
    margin-bottom: 2px;
}

.stat-value {
    font-size: 1rem;
    font-weight: bold;
    color: #fff;
}

#steckbrief-desc {
    font-size: 0.85rem;
    line-height: 1.4;
    color: #dfe6e9;
    flex-grow: 1;
}

#pse-spawn-btn {
    background-color: #2ed573;
    color: white;
    border: none;
    padding: 10px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: bold;
    font-size: 0.95rem;
    transition: background-color 0.2s, transform 0.1s;
    box-shadow: 0 4px 6px rgba(0,0,0,0.2);
    width: 100%;
}

#pse-spawn-btn:hover {
    background-color: #26af5a;
}

#pse-spawn-btn:active {
    transform: scale(0.95);
}

/* Bohr Model (Atomschalen-Visualisierung) */
.bohr-model-container {
    height: 140px;
    width: 100%;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.25);
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.03);
    overflow: hidden;
}

.bohr-nucleus {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background-color: #ff7675;
    position: absolute;
    box-shadow: 0 0 10px #ff7675;
    z-index: 5;
}

.bohr-shell {
    position: absolute;
    border: 1px dashed rgba(255,255,255,0.15);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    animation: rotate-shell 20s linear infinite;
}

.bohr-shell:nth-child(1) { width: 50px; height: 50px; animation-duration: 8s; }
.bohr-shell:nth-child(2) { width: 90px; height: 90px; animation-duration: 15s; }
.bohr-shell:nth-child(3) { width: 130px; height: 130px; animation-duration: 25s; }

.bohr-electron {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background-color: #54a0ff;
    position: absolute;
    box-shadow: 0 0 5px #54a0ff;
}

@keyframes rotate-shell {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.hidden {
    display: none !important;
}

/* REAKTOR-BOX STYLES */
#reactor-box {
    position: absolute;
    bottom: 20px;
    right: 20px;
    width: 320px;
    background: rgba(30, 39, 46, 0.95);
    border: 2px dashed #3498db;
    border-radius: 12px;
    padding: 15px;
    box-shadow: var(--shadow);
    z-index: 50;
    display: flex;
    flex-direction: column;
    gap: 10px;
    transition: border-color 0.2s, background-color 0.2s, transform 0.2s;
    backdrop-filter: blur(8px);
}

#reactor-box.drag-over {
    border-color: #2ecc71;
    background: rgba(46, 204, 113, 0.2);
    transform: scale(1.02);
}

.reactor-header h3 {
    font-size: 1.05rem;
    color: #fff;
    margin: 0;
    text-align: center;
    letter-spacing: 0.5px;
}

.reactor-body {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

#reactor-contents-summary {
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 10px;
    min-height: 80px;
    font-size: 0.85rem;
    color: var(--text-muted);
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-content: flex-start;
}

.reactor-buttons {
    display: flex;
    gap: 10px;
}

.reactor-btn {
    flex: 1;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 6px;
    padding: 10px 14px;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.15s, transform 0.1s;
    font-size: 0.85rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.15);
}

.reactor-btn:hover {
    background: #2980b9;
}

.reactor-btn:active {
    transform: scale(0.95);
}

.reactor-btn.secondary {
    background: #7f8c8d;
}

.reactor-btn.secondary:hover {
    background: #95a5a6;
}

.reactor-badge {
    display: inline-flex;
    align-items: center;
    padding: 6px 10px;
    border-radius: 6px;
    font-size: 0.8rem;
    font-weight: bold;
    cursor: pointer;
    user-select: none;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    border: 1px solid rgba(0,0,0,0.15);
    transition: transform 0.1s, box-shadow 0.1s;
    background-image: radial-gradient(circle at 30% 30%, rgba(255, 255, 255, 0.15) 0%, rgba(0, 0, 0, 0.1) 100%);
}

.reactor-badge:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 8px rgba(0,0,0,0.3);
}

.atom-badge {
    border-radius: 6px;
}

.molecule-badge {
    border-radius: 6px;
}

.badge-count {
    margin-right: 6px;
    opacity: 0.75;
    background: rgba(0, 0, 0, 0.1);
    padding: 1px 4px;
    border-radius: 4px;
}

.empty-text {
    width: 100%;
    text-align: center;
    line-height: 60px;
    font-style: italic;
    color: #7f8c8d;
}