body {
    background: #101820;
    margin: 0;
    overflow: hidden;
    font-family: Helvetica, Arial, sans-serif;
}

#header {
    position: absolute;
    width: 100%;
    top: 0;
    left: 0;
    z-index: 10;
    text-align: center;
    background: rgba(16, 24, 32,); /* More transparent */
    padding: 16px 0 8px 0;
    
}
#header h1 {
    font-family: 'Orbitron';
    color: #00fff7;
    font-size: 2.8em;
    letter-spacing: 4px;
    text-shadow:
        0 0 16px #00fff7,
        0 0 32px #00fff788,
        0 2px 4px #000a;
    margin: 0 0 4px 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
}
#header p {
    color: #aaa;
    margin-top: 24px;
    font-size: x-large;
}
#propertyFilter {
    font-size: 1em;
    margin-bottom: 28px;
    padding: 4px 12px;
    border-radius: 6px;
    border: 1px solid #00bcd4;
    background: #182030;
    color: #8ff;
    transition: 
        box-shadow 0.3s, 
        background 0.3s, 
        transform 0.25s cubic-bezier(.25,.8,.25,1), 
        opacity 0.25s cubic-bezier(.25,.8,.25,1);
    box-shadow: 0 2px 8px 0 rgba(0,255,255,0.08);
    opacity: 1;
    transform: scale(1);
}

#propertyFilter:focus,
#propertyFilter:hover {
    box-shadow: 0 4px 24px 0 rgba(0,255,255,0.18);
    background: #223040;
    border-color: #fff;
    color: #00bcd4;
    opacity: 1;
    transform: scale(1.06);
    z-index: 20;
    animation: dropdownOpen 0.35s cubic-bezier(.25,.8,.25,1);
}

@keyframes dropdownOpen {
    from {
        filter: blur(2px) brightness(0.8);
        transform: scaleY(0.95) scale(1);
    }
    to {
        filter: blur(0) brightness(1);
        transform: scaleY(1) scale(1.06);
    }
}
#menu {
    position: absolute;
    bottom: 20px;
    width: 100%;
    text-align: center;
    z-index: 10;
    left: 0;
}
.element {
    background: rgba(0, 32, 32, 0.95);
    width: 120px;
    height: 160px;
    border: 2.5px solid transparent;
    font-family: Helvetica, sans-serif;
    text-align: center;
    line-height: normal;
    cursor: default;
    transition: 
        opacity 0.5s,
        border-color 0.5s,
        box-shadow 0.5s,
        transform 0.3s cubic-bezier(.25,.8,.25,1),
        filter 0.3s;
    z-index: 1;
    overflow: visible;
}
.element::before {
    content: "";
    position: absolute;
    inset: -10px;
    border-radius: 18px;
    z-index: 0;
    opacity: 0;
    transition: opacity 0.3s, box-shadow 0.3s;
    pointer-events: none;
    will-change: box-shadow, opacity;
}
.element[data-property="Alkali Metal"]::before { box-shadow: 0 0 48px 16px #ff00cc55; }
.element[data-property="Alkaline Earth Metal"]::before { box-shadow: 0 0 48px 16px #00ffea55; }
.element[data-property="Transition Metal"]::before { box-shadow: 0 0 48px 16px #00e1ff55; }
.element[data-property="Post-transition Metal"]::before { box-shadow: 0 0 48px 16px #00ff6a55; }
.element[data-property="Metalloid"]::before { box-shadow: 0 0 48px 16px #fffb0055; }
.element[data-property="Nonmetal"]::before { box-shadow: 0 0 48px 16px #00ff2f55; }
.element[data-property="Halogen"]::before { box-shadow: 0 0 48px 16px #ff910055; }
.element[data-property="Noble Gas"]::before { box-shadow: 0 0 48px 16px #a259ff55; }
.element[data-property="Lanthanide"]::before { box-shadow: 0 0 48px 16px #ff297555; }
.element[data-property="Actinide"]::before { box-shadow: 0 0 48px 16px #ff174455; }
.element[data-property="Unknown"]::before { box-shadow: 0 0 48px 16px #bdbdbd55; }
.element:hover {
    border: 2.5px solid #fff;
    filter: drop-shadow(0 0 1px #fff);
    /* Remove elevation and scale from .element itself */
    transform: none;
    z-index: 10;
}
.element:hover .symbol {
    /* Pop-out animation for the symbol */
    transform: scale(1.25);
    color: #fff;
    text-shadow:
        0 0 24px #fff,
        0 0 12px currentColor,
        0 0 2px #fff;
    filter: brightness(1.5);
    transition:
        transform 0.3s cubic-bezier(.25,.8,.25,1),
        color 0.3s,
        text-shadow 0.3s,
        filter 0.3s;
}
.element:hover::before {
    opacity: 1;
    animation: neonPulse 1.2s infinite alternate-reverse;
}
@keyframes neonPulse {
    from { box-shadow: 0 0 48px 16px var(--neon-color, #fff5); }
    to   { box-shadow: 0 0 64px 24px var(--neon-color, #fff8); }
}
.element .number {
    position: absolute;
    top: 16px;
    right: 16px;
    font-size: 13px;
    background: #00bcd4;
    color: #fff;
    border-radius: 50%;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    box-shadow: 0 0 8px #00bcd4;
}
body.light .element .number {
    background: #1976d2;
    color: #fff;
    box-shadow: 0 0 8px #90caf9;
}
.element .symbol {
    position: absolute;
    top: 40px;
    left: 0px;
    right: 0px;
    font-size: 60px;
    font-weight: bolder;
    color: #fff
    /* text-shadow: 0 0 10px rgba(0, 255, 255, 0.1); */
}
.element .details {
    position: absolute;
    bottom: 15px;
    left: 0px;
    right: 0px;
    font-size: 12px;
    color: rgba(127, 255, 255, 0.75);
}
button {
    color: rgba(127, 255, 255, 0.75);
    background: transparent;
    outline: 1px solid rgba(127, 255, 255, 0.75);
    border: 0px;
    padding: 5px 10px;
    cursor: pointer;
    font-size: 1em;
    border-radius: 6px;
    margin: 0 4px;
}
button:hover {
    background-color: rgba(0, 255, 255, 0.5);
}
button:active {
    color: #000000;
    background-color: rgba(0, 255, 255, 0.75);
}
#hoverInfo {
    display: none;
    position: fixed;
    z-index: 1000;
    background: rgba(0,32,32,0.97);
    color: #fff;
    padding: 16px 22px;
    border-radius: 12px;
    pointer-events: none;
    font-size: 1.1em;
    box-shadow: 0 4px 24px #000a;
    min-width: 180px;
    max-width: 320px;
    border: 1.5px solid #00bcd4;
    transition: opacity 0.2s, transform 0.2s;
    opacity: 0.98;
}


/* Neon border colors by property */
.element[data-property="Alkali Metal"] {
    border-color: #ff00cc;
    box-shadow: 0 0 16px 2px #ff00cc80;
}
.element[data-property="Alkaline Earth Metal"] {
    border-color: #00ffea;
    box-shadow: 0 0 16px 2px #00ffea80;
}
.element[data-property="Transition Metal"] {
    border-color: #00e1ff;
    box-shadow: 0 0 16px 2px #00e1ff80;
}
.element[data-property="Post-transition Metal"] {
    border-color: #00ff6a;
    box-shadow: 0 0 16px 2px #00ff6a80;
}
.element[data-property="Metalloid"] {
    border-color: #fffb00;
    box-shadow: 0 0 16px 2px #fffb0080;
}
.element[data-property="Nonmetal"] {
    border-color: #00ff2f;
    box-shadow: 0 0 16px 2px #00ff2f80;
}
.element[data-property="Halogen"] {
    border-color: #ff9100;
    box-shadow: 0 0 16px 2px #ff910080;
}
.element[data-property="Noble Gas"] {
    border-color: #a259ff;
    box-shadow: 0 0 16px 2px #a259ff80;
}
.element[data-property="Lanthanide"] {
    border-color: #ff2975;
    box-shadow: 0 0 16px 2px #ff297580;
}
.element[data-property="Actinide"] {
    border-color: #ff1744;
    box-shadow: 0 0 16px 2px #ff174480;
}
.element[data-property="Unknown"] {
    border-color: #bdbdbd;
    box-shadow: 0 0 16px 2px #bdbdbd80;
}

/* Focused (clicked) element effect */ 
.element.focused {
    z-index: 999 !important;
    transform: scale(1.25) translateY(-24px) !important;
    box-shadow: 0 0 64px 16px currentColor, 0 0 48px 16px currentColor !important;
    filter: brightness(1.3) drop-shadow(0 0 16px currentColor);
    transition: 
        transform 0.4s cubic-bezier(.25,.8,.25,1),
        box-shadow 0.4s,
        filter 0.4s;
}
.element.blurred {
    filter: blur(4px) grayscale(0.7) brightness(0.7);
    opacity: 0.4 !important;
    pointer-events: none !important;
    transition: filter 0.4s, opacity 0.4s;
}

/* Grid background effect */
.grid-container {
    background: #000; /* Black background */
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 0;
    pointer-events: none; /* So it doesn't block UI */
}

.grid-element {
    display: none; /* Hide grid elements */
}

@keyframes glow {
    0% {
        opacity: 0.2;
    }
    100% {
        opacity: 0.4;
    }
}

@media (max-width: 600px) {
    #header { padding: 8px 0 4px 0; }
    .element {
        width: 70px;
        height: 90px;
    }
    .element .symbol {
        font-size: 28px;
    }
    .element .details {
        font-size: 9px;
    }
    #menu button {
        font-size: 0.9em;
        padding: 4px 6px;
    }
}

/* Responsive header and menu */
#header {
    padding: 16px 0 8px 0;
}
#menu {
    position: absolute;
    bottom: 20px;
    width: 100%;
    text-align: center;
    z-index: 10;
    left: 0;
}

/* Responsive periodic table elements */
.element {
    width: 120px;
    height: 160px;
    font-size: 1em;
}
.element .symbol {
    font-size: 60px;
}
.element .details {
    font-size: 12px;
}
.element .number {
    width: 28px;
    height: 28px;
    font-size: 13px;
}

/* --- Responsive breakpoints --- */
@media (max-width: 1100px) {
    .element {
        width: 90px;
        height: 120px;
    }
    .element .symbol {
        font-size: 38px;
    }
    .element .details {
        font-size: 10px;
    }
    .element .number {
        width: 22px;
        height: 22px;
        font-size: 11px;
    }
}

@media (max-width: 800px) {
    #header h1 {
        font-size: 1.3em;
    }
    #header p {
        font-size: 1em;
    }
    .element {
        width: 60px;
        height: 80px;
    }
    .element .symbol {
        font-size: 22px;
    }
    .element .details {
        font-size: 8px;
    }
    .element .number {
        width: 16px;
        height: 16px;
        font-size: 8px;
    }
    #menu button {
        font-size: 0.9em;
        padding: 4px 6px;
    }
    #propertyFilter {
        font-size: 0.9em;
        padding: 2px 6px;
    }
}

@media (max-width: 500px) {
    #header {
        padding: 8px 0 4px 0;
    }
    #header h1 {
        font-size: 1em;
        letter-spacing: 1px;
    }
    #header p {
        font-size: 0.9em;
    }
    .element {
        width: 38px;
        height: 52px;
        min-width: 0;
        min-height: 0;
    }
    .element .symbol {
        font-size: 13px;
    }
    .element .details {
        font-size: 6px;
    }
    .element .number {
        width: 10px;
        height: 10px;
        font-size: 6px;
    }
    #menu button {
        font-size: 0.8em;
        padding: 2px 4px;
        margin: 0 2px;
    }
    #propertyFilter {
        font-size: 0.8em;
        padding: 1px 3px;
    }
}

/* Make sure tooltips and dropdowns fit on small screens */
#hoverInfo {
    min-width: 100px;
    max-width: 90vw;
    font-size: 0.95em;
    padding: 8px 10px;
    word-break: break-word;
}