/* ── PhET Scaling Base ───────────────────────────────────── */
html, body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

/* PhET Stage — scalable container */
#phet-stage {
    position: absolute;
    top: 0;
    left: 0;
    transform-origin: top left;
    overflow-y: auto;
    background: #020617;
    display: flex;
    flex-direction: column;
    align-items: center;
}

:root {
    --bg-dark: #020617;
    --card-bg: rgba(30, 41, 59, 0.4);
    --card-border: rgba(255, 255, 255, 0.05);
    --alkali: #f87171;
    --alkaline: #fbbf24;
    --transition: #60a5fa;
    --basic: #34d399;
    --metalloid: #fb923c;
    --nonmetal: #818cf8;
    --halogen: #f472b6;
    --noble: #a78bfa;
    --lanthanide: #2dd4bf;
    --actinide: #e879f9;
}

body.periodic-dark {
    background: var(--bg-dark);
    color: #f8fafc;
    overflow: hidden;
    height: 100%;
    width: 100%;
}

.table-app {
    display: flex;
    flex-direction: column;
    padding: 20px;
    height: 100%;
    width: 100%;
    box-sizing: border-box;
    gap: 15px;
    position: relative;
    z-index: 10;
    overflow: hidden;
    flex: 1;
}

.glass-nav {
    flex-shrink: 0;
    position: relative;
    width: 100%;
    padding: 15px 30px;
}

/* Modal Styling */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(8px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    width: 90%;
    max-width: 900px;
    background: rgba(15, 23, 42, 0.95);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 30px;
    padding: 40px;
    position: relative;
    transform: scale(0.9);
    transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 0 50px rgba(0, 0, 0, 0.5);
}

.modal-overlay.active .modal-content {
    transform: scale(1);
}

.close-btn {
    position: absolute;
    top: 25px;
    right: 25px;
    background: none;
    border: none;
    color: #fff;
    font-size: 2rem;
    cursor: pointer;
    opacity: 0.6;
    transition: 0.3s;
}

.close-btn:hover {
    opacity: 1;
    transform: rotate(90deg);
}

.modal-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
}

/* Modal Visualization */
.modal-visual {
    position: relative;
    height: 400px;
    display: flex;
    justify-content: center;
    align-items: center;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.02) 0%, transparent 70%);
}

.atom-container {
    position: relative;
    width: 300px;
    height: 300px;
    display: flex;
    justify-content: center;
    align-items: center;
    transform-style: preserve-3d;
    z-index: 20;
    perspective: 1000px;
}

.nucleus {
    position: absolute;
    width: 2px;
    height: 2px;
    z-index: 30;
    transform-style: preserve-3d;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* Static Glow that doesn't rotate/fade */
.nucleus-glow {
    position: absolute;
    width: 40px;
    height: 40px;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
    z-index: 25;
}

@keyframes rotateNucleus {
    0% {
        transform: rotateY(0deg) rotateX(0deg);
    }

    100% {
        transform: rotateX(360deg) rotateY(360deg);
    }
}

.proton,
.neutron {
    position: absolute;
    border-radius: 50%;
    backface-visibility: visible;
}

.proton {
    background: radial-gradient(circle at 35% 35%, #fff 0%, #ff4d4d 40%, #a00 80%, #400 100%);
    box-shadow: inset -1px -1px 2px rgba(0, 0, 0, 0.8), 0 0 5px rgba(255, 0, 0, 0.3);
}

.neutron {
    background: radial-gradient(circle at 35% 35%, #fff 0%, #4d4dff 40%, #00a 80%, #004 100%);
    box-shadow: inset -1px -1px 2px rgba(0, 0, 0, 0.8), 0 0 5px rgba(0, 0, 255, 0.3);
}

.orbital {
    position: absolute;
    border: 0.5px solid rgba(255, 255, 255, 0.1);
    /* Even subtler */
    border-radius: 50%;
    transform-style: preserve-3d;
}

@keyframes spinOrbital {
    from {
        transform: rotateZ(0deg);
    }

    to {
        transform: rotateZ(360deg);
    }
}

.electron-ring {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
}

.electron {
    width: 4px;
    height: 4px;
    /* Much smaller */
    background: #4ade80;
    border-radius: 50%;
    position: absolute;
    top: -2px;
    left: calc(50% - 2px);
    box-shadow: 0 0 8px #4ade80, 0 0 2px #fff;
    z-index: 100;
}

.modal-hero {
    position: absolute;
    text-align: center;
    pointer-events: none;
    z-index: 1;
    /* Lower than atom */
    opacity: 0.2;
    /* Subtly in background */
}

.hero-number {
    font-size: 1.5rem;
    font-weight: 700;
    opacity: 0.4;
    position: absolute;
    top: -80px;
    left: -80px;
}

.hero-symbol {
    font-size: 8rem;
    font-weight: 800;
    margin: 0;
    font-family: 'Space Grotesk';
    background: linear-gradient(180deg, #fff, var(--group-color, #ccc));
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.hero-name {
    font-size: 1.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 4px;
    color: #fff;
    margin-top: -10px;
}

/* Modal Info */
.modal-stat-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 15px;
    margin-bottom: 25px;
}

.modal-stat {
    background: rgba(255, 255, 255, 0.03);
    padding: 15px 20px;
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.modal-stat label {
    display: block;
    font-size: 0.8rem;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.4);
    margin-bottom: 5px;
    letter-spacing: 1px;
}

.modal-stat span {
    font-size: 1.2rem;
    font-weight: 600;
    color: #e2e8f0;
}

.modal-desc-box {
    background: rgba(0, 0, 0, 0.2);
    padding: 20px;
    border-radius: 15px;
    border-left: 4px solid var(--group-color, #a855f7);
    color: #94a3b8;
    line-height: 1.6;
}

/* Layout Wrappers */
.main-workspace {
    flex: 1;
    /* Expand to full width */
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 10px;
    height: 100%;
}


/* Periodic Grid */
.table-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 8px;
    /* Reduced gap */
    justify-content: stretch;
    perspective: 1000px;
    min-height: 0;
    /* vital for flex-children shrinking */
    padding-bottom: 5px;
}

.periodic-grid {
    display: grid;
    grid-template-columns: repeat(18, 1fr);
    grid-template-rows: repeat(7, minmax(0, 1fr));
    gap: 4px;
    width: 100%;
    flex: 7;
    /* Proportionate heights */
}

.f-block {
    grid-template-columns: repeat(18, 1fr);
    grid-template-rows: repeat(2, minmax(0, 1fr));
    flex: 2;
}

.element-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 6px;
    padding: 2px 4px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    height: 100%;
}

.element-card:hover {
    transform: scale(1.15) translateZ(20px);
    z-index: 100;
    box-shadow: 0 15px 30px -5px rgba(0, 0, 0, 0.5);
    border-color: rgba(255, 255, 255, 0.3);
    background: rgba(255, 255, 255, 0.1);
}

.element-card .number {
    position: absolute;
    top: 4px;
    left: 6px;
    font-size: 0.6rem;
    opacity: 0.5;
    font-weight: 700;
}

.element-card .symbol {
    font-size: 1.4rem;
    font-weight: 800;
    font-family: 'Space Grotesk';
}

.element-card .name {
    font-size: 0.5rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    opacity: 0.7;
    margin-top: 2px;
}

.element-card.active-hover {
    box-shadow: 0 0 20px var(--group-color);
    border-color: var(--group-color);
}

/* Group Colors */
.element-card[data-group="alkali"] {
    background: rgba(248, 113, 113, 0.1);
    border-color: rgba(248, 113, 113, 0.2);
}

.element-card[data-group="alkaline"] {
    background: rgba(251, 191, 36, 0.1);
    border-color: rgba(251, 191, 36, 0.2);
}

.element-card[data-group="transition"] {
    background: rgba(96, 165, 250, 0.1);
    border-color: rgba(96, 165, 250, 0.2);
}

.element-card[data-group="basic"] {
    background: rgba(52, 211, 153, 0.1);
    border-color: rgba(52, 211, 153, 0.2);
}

.element-card[data-group="metalloid"] {
    background: rgba(251, 146, 60, 0.1);
    border-color: rgba(251, 146, 60, 0.2);
}

.element-card[data-group="nonmetal"] {
    background: rgba(129, 140, 248, 0.1);
    border-color: rgba(129, 140, 248, 0.2);
}

.element-card[data-group="halogen"] {
    background: rgba(244, 114, 182, 0.1);
    border-color: rgba(244, 114, 182, 0.2);
}

.element-card[data-group="noble"] {
    background: rgba(167, 139, 250, 0.1);
    border-color: rgba(167, 139, 250, 0.2);
}

.element-card[data-group="lanthanide"] {
    background: rgba(45, 212, 191, 0.1);
    border-color: rgba(45, 212, 191, 0.2);
}

.element-card[data-group="actinide"] {
    background: rgba(232, 121, 249, 0.1);
    border-color: rgba(232, 121, 249, 0.2);
}

.element-card[data-group="alkali"]:hover {
    border-color: var(--alkali);
    box-shadow: 0 0 15px var(--alkali);
}

.element-card[data-group="alkaline"]:hover {
    border-color: var(--alkaline);
    box-shadow: 0 0 15px var(--alkaline);
}

.element-card[data-group="transition"]:hover {
    border-color: var(--transition);
    box-shadow: 0 0 15px var(--transition);
}

.element-card[data-group="basic"]:hover {
    border-color: var(--basic);
    box-shadow: 0 0 15px var(--basic);
}

.element-card[data-group="metalloid"]:hover {
    border-color: var(--metalloid);
    box-shadow: 0 0 15px var(--metalloid);
}

.element-card[data-group="nonmetal"]:hover {
    border-color: var(--nonmetal);
    box-shadow: 0 0 15px var(--nonmetal);
}

.element-card[data-group="halogen"]:hover {
    border-color: var(--halogen);
    box-shadow: 0 0 15px var(--halogen);
}

.element-card[data-group="noble"]:hover {
    border-color: var(--noble);
    box-shadow: 0 0 15px var(--noble);
}

.element-card[data-group="lanthanide"]:hover {
    border-color: var(--lanthanide);
    box-shadow: 0 0 15px var(--lanthanide);
}

.element-card[data-group="actinide"]:hover {
    border-color: var(--actinide);
    box-shadow: 0 0 15px var(--actinide);
}

/* Top Controls */
.top-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 20px;
    padding: 15px 25px;
    width: 100%;
}

.search-stats {
    display: flex;
    align-items: center;
    gap: 20px;
}

.search-box {
    position: relative;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 10px 15px;
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 200px;
}

.search-box i {
    color: #94a3b8;
}

.search-box input {
    background: transparent;
    border: none;
    color: white;
    font-size: 0.9rem;
    width: 100%;
    outline: none;
}

.filter-legend {
    background: transparent;
}

.horizontal-legend .legend-grid {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 8px;
}

.legend-item {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.05);
    color: #94a3b8;
    padding: 8px 12px;
    border-radius: 8px;
    font-size: 0.8rem;
    text-align: left;
    cursor: pointer;
    transition: all 0.2s;
}

.legend-item:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateX(5px);
}

.legend-item[data-group="alkali"]:hover {
    color: var(--alkali);
    border-color: var(--alkali);
}

.legend-item[data-group="alkaline"]:hover {
    color: var(--alkaline);
    border-color: var(--alkaline);
}

.legend-item[data-group="transition"]:hover {
    color: var(--transition);
    border-color: var(--transition);
}

.legend-item[data-group="noble"]:hover {
    color: var(--noble);
    border-color: var(--noble);
}

.legend-item.active {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border-color: rgba(255, 255, 255, 0.2);
}

.sim-stats {
    display: flex;
    align-items: center;
    gap: 15px;
    color: #94a3b8;
    font-size: 0.9rem;
    white-space: nowrap;
}

.sim-stats p {
    margin: 0;
}

.btn-small {
    padding: 8px 16px;
    font-size: 0.8rem;
    border-radius: 8px;
}

/* Animations */
@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }

    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.vignette {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, transparent 60%, rgba(0, 7, 20, 0.8) 100%);
    pointer-events: none;
    z-index: 5;
}

.extra-spacing {
    height: 0;
    flex: 0.5;
    /* Spacing proportion between main & f-block */
}

/* Responsive Hacks */
@media (max-width: 1200px) {
    .periodic-grid {
        gap: 3px;
    }

    .element-card .symbol {
        font-size: 1rem;
    }
}