body {
    margin: 0;
    min-height: 100vh;

    background: linear-gradient(
        135deg,
        #0f172a,
        #1e3a8a
    );

    color: white;
    font-family: Arial, sans-serif;
}
.start-btn {
    display: inline-block;
    margin-top: 20px;
    padding: 14px 32px;

    background: white;
    color: #111;

    border-radius: 14px;
    text-decoration: none;

    font-weight: bold;
    font-size: 1.1rem;

    transition: 0.3s ease;
}
.start-btn:hover {
    transform: scale(1.05);
}
.back-home {
    position: relative;
    top: 20px;
    left: 20px;

    color: white;
    text-decoration: none;
    font-weight: bold;

    padding: 10px 16px;
    border-radius: 10px;

    background: rgba(255,255,255,0.1);
    backdrop-filter: blur(6px);

    transition: 0.3s ease;
    z-index: 99999;
}
.back-home:hover {
    background: rgba(255,255,255,0.2);
    transform: translateX(-3px);
}


.navbar {
    position: sticky;
    top: 0;

    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 1rem 2rem;

    background: rgba(10, 20, 60, 0.85);

    backdrop-filter: blur(10px);

    border-bottom: 1px solid rgba(255,255,255,0.1);

    z-index: 1000;
}
.nav-logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
}
.nav-links {
    display: flex;
    gap: 2rem;

    list-style: none;
}
.nav-links a {
    color: white;
    text-decoration: none;

    font-weight: 600;

    transition: 0.3s;
}
.nav-links a:hover {
    color: cyan;
    transition: 0.3s ease;
}


/* HERO */
.hero {
    text-align: center;

    padding: 6rem 2rem 4rem;
}
.hero h1 {
    font-size: 4rem;
    margin-bottom: 1rem;
}
.hero p {
    max-width: 700px;
    margin: auto;

    font-size: 1.2rem;
    opacity: 0.85;
}
.hero-btn {
    margin-top: 2rem;

    padding: 1rem 2rem;

    border: none;
    border-radius: 12px;

    background: white;
    color: #0f172a;

    font-size: 1rem;
    font-weight: bold;

    cursor: pointer;
}

/* COURSES */
.courses {
    display: flex;
    justify-content: center;
    gap: 2rem;

    padding: 2rem;
    flex-wrap: wrap;
}
.course-card {
    width: 280px;

    padding: 2rem;
    min-height: 220px;

    border-radius: 20px;

    background: rgba(255,255,255,0.08);

    backdrop-filter: blur(10px);

    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    transition: transform 0.25s ease,
            box-shadow 0.25s ease;

}
.course-card:hover {
    transform: translateY(-8px);

    box-shadow:
        0 20px 40px rgba(0,0,0,0.3);
}
.card-link {
    text-decoration: none;
    color: inherit;
}


/* COMPUTER BASICS SECTION */ 
.computer-card:hover {
    transform: translateY(-6px) scale(1.01);

    box-shadow:
        0 0 25px rgba(0, 255, 255, 0.35);

    border: 1px solid rgba(255,255,255,0.25);
}
.lesson-hero {
    max-width: 900px;
    margin: 60px auto;
    text-align: center;
    animation: fadeUp 1s ease;
    padding: 80px 20px 80px;
}
.lesson-hero h1 {
    font-size: 2.5rem;
    margin-bottom: 30px;
    text-shadow:
        0 0 10px rgba(255,255,255,0.3);
}
.hero-text {
    font-size: 1.3rem;
    line-height: 1.9;
    opacity: 0.9;
    margin-bottom: 35px;
}
.computer-cycle-preview {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
    margin-top: 40px;
}
.cycle-pill {
    padding: 18px 40px;
    border-radius: 14px;
    background: rgba(255,255,255,0.05);
    border: 2px solid rgba(255,255,255,0.15);
    font-size: 1.1rem;
}
.lesson-section {
    display: flex;
    align-items: center;
    gap: 80px;

    max-width: 1200px;
    margin: 0 auto;
    padding: 120px 20px;
    padding-top: 150px;
}
.lesson-text,
.lesson-demo {
    flex: 1;
}
.lesson-text h2 {
    font-size: 2.5rem;
    margin-bottom: 40px;
    text-align: center;
}
.lesson-text {
    max-width: 550px;
    font-size: 1.3rem;
    line-height: 1.9;
    opacity: 0.9;
    margin-bottom: 35px;
    text-align: center;
}
h3 {
    font-size: 2rem;
    margin-bottom: 25px;
    text-align: center;
}
.input-content {
    max-width: 750px;
    margin: 0 auto;
    text-align: center;
}
.input-content p {
    margin-bottom: 30px;
}
.input-buttons {
    display: flex;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
    margin-top: 30px;
}
.input-buttons button {
    padding: 12px 24px;
    border-radius: 12px;
    border: none;
    cursor: pointer;

    background: rgba(255,255,255,0.1);
    color: white;

    font-size: 1rem;
    font-weight: bold;

    transition: all 0.3s ease;
}
.input-buttons button:hover {
    transform: translateY(-3px);
    box-shadow: 0 0 15px rgba(0,255,255,0.5);
}
#input-demo {
    margin-top: 40px;
    text-align: center;
    min-height: 200px;
}
.keyboard-result {
    color:#031b2c
}

/* PHYSICS SECTION */
.lesson-page {
    width: 80%;
    margin: auto;
    padding-top: 120px;
    color: white;
}
.lesson-page h1 {
    font-size: 2rem;
    margin-bottom: 20px;
}
.lesson-intro {
    font-size: 1.3rem;
    margin-bottom: 50px;
    opacity: 0.9;
}
.lesson-card {
    background: rgba(255,255,255,0.1);

    border-radius: 20px;

    padding: 30px;

    margin-bottom: 30px;

    backdrop-filter: blur(10px);
}
.lesson-card h2 {
    margin-bottom: 15px;
}
.back-home {
    position: fixed;

    top: 20px;
    left: 20px;

    background: rgba(255,255,255,0.15);

    padding: 12px 20px;

    border-radius: 12px;

    color: white;

    text-decoration: none;

    font-weight: bold;
}
.physics-card {
    cursor: pointer;
    transition: transform 0.25s ease, 
                box-shadow 0.25s ease,
                border 0.25s ease;
}
.physics-card:hover {
    transform: translateY(-6px) scale(1.01);

    box-shadow:
        0 0 25px rgba(0, 255, 255, 0.35);

    border: 1px solid rgba(255,255,255,0.25);
}
.explore-text {
    display: inline-block;
    margin-top: 12px;
    opacity: 0.7;
    font-size: 0.9rem;
    transition: transform 0.2s ease;
}
.physics-card:hover .explore-text {
    transform: translateX(5px);
}
.energy-hero {
    position: relative;
    text-align: center;
    padding-top: 120px;
    min-height: 70vh;
    overflow: hidden;
}
.energy-intro {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
    padding: 2rem;
    line-height: 1.8;
    animation: fadeUp 1.5s ease;
}
@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}
.energy-title {
    font-size: 2rem;
    font-weight: bold;
    color: white;
    margin-bottom: 20px;
    text-shadow:
        0 0 10px rgba(255,255,255,0.4),
        0 0 30px rgba(0,255,255,0.25);    
}
.energy-subtitle {
    font-size: 1.1rem;
    margin: 0 auto;
    max-width: 700px;
    line-height: 1.9;
    color: rgba(255,255,255,0.92);

}
.energy-particles span {
    position: absolute;

    width: 14px;
    height: 14px;

    background: cyan;
    border-radius: 50%;

    box-shadow:
        0 0 20px cyan,
        0 0 40px cyan;

    animation: floatParticle 8s infinite ease-in-out;
}
.energy-particles span:nth-child(1) {
    top: 20%;
    left: 15%;
    animation-delay: 0s;
}
.energy-particles span:nth-child(2) {
    top: 40%;
    left: 70%;
    animation-delay: 2s;
}
.energy-particles span:nth-child(3) {
    top: 65%;
    left: 30%;
    animation-delay: 4s;
}
.energy-particles span:nth-child(4) {
    top: 30%;
    left: 85%;
    animation-delay: 1s;
}
.energy-particles span:nth-child(5) {
    top: 75%;
    left: 55%;
    animation-delay: 3s;
}
@keyframes floatParticle {

    0% {
        transform: translateY(0px);
        opacity: 0.3;
    }

    50% {
        transform: translateY(-40px);
        opacity: 1;
    }

    100% {
        transform: translateY(0px);
        opacity: 0.3;
    }
}
.energy-transfer-section {
    display: flex;

    justify-content: space-between;
    align-items: center;

    gap: 60px;

    padding: 120px 10%;

    flex-wrap: wrap;
}

.energy-text {
    flex: 1;
    min-width: 300px;
}
.energy-text h2 {
    font-size: 2rem;
    margin-bottom: 20px;
}
.energy-text p {
    font-size: 1.0rem;
    line-height: 1.8;
    color: rgba(255,255,255,0.85);
    max-width: 800px;
}
.energy-btn {
    margin-top: 30px;

    padding: 14px 28px;

    border: none;
    border-radius: 12px;

    background: cyan;
    color: black;

    font-weight: bold;
    font-size: 1rem;

    cursor: pointer;

    transition: 0.25s ease;
}
.energy-btn:hover {
    transform: scale(1.05);

    box-shadow:
        0 0 20px cyan;
}
.energy-demo {
    flex: 1;

    min-width: 300px;

    display: flex;
    align-items: center;
    justify-content: center;

    position: relative;
}
.energy-source {
    width: 50px;
    height: 50px;

    border-radius: 50%;

    background: cyan;

    box-shadow:
        0 0 30px cyan;
}
.energy-line {
    width: 220px;
    height: 6px;

    background: rgba(255,255,255,0.2);

    margin: 0 20px;

    border-radius: 10px;

    position: relative;
    overflow: hidden;
}
.energy-pulse {
    width: 30px;
    height: 100%;

    background: cyan;

    position: absolute;
    left: -40px;

    border-radius: 10px;

    box-shadow:
        0 0 20px cyan;

    opacity: 0;
}
.energy-ball {
    width: 60px;
    height: 60px;

    border-radius: 50%;

    background: white;

    transition:
        transform 0.5s ease,
        box-shadow 0.5s ease;
}
body {
    background:
        radial-gradient(circle at top, #1d4ed8 0%, #0b1026 70%);

    overflow-x: hidden;
}
.stars {
    position: fixed;

    top: 0;
    left: 0;

    width: 100%;
    height: 100%;

    pointer-events: none;

    background-image:
        radial-gradient(white 1px, transparent 1px),
        radial-gradient(cyan 1px, transparent 1px);

    background-size:
        120px 120px,
        200px 200px;

    opacity: 0.15;

    animation: driftStars 60s linear infinite;
}
@keyframes driftStars {
    from {
        transform: translateY(0px);
    }

    to {
        transform: translateY(-100px);
    }
}
.nebula {
    position: fixed;

    width: 800px;
    height: 800px;

    top: -200px;
    right: -200px;

    background:
        radial-gradient(circle,
        rgba(0,255,255,0.15),
        transparent 70%);

    filter: blur(80px);

    pointer-events: none;
}
.energy-ball {
    animation: pulse 2.5s ease-in-out infinite;
}
.energy-line {
    position: relative;
    overflow: hidden;
}
.energy-line::after {
    content: "";

    position: absolute;
    left: -40px;
    top: 0;

    width: 40px;
    height: 100%;

    background: rgba(255,255,255,0.8);

    filter: blur(4px);

    animation: travel 2s linear infinite;
}
.title-glow {
    position: absolute;

    top: 10%;
    left: 50%;

    transform: translateX(-50%);

    width: 700px;
    height: 700px;

    background:
        radial-gradient(circle,
        rgba(0,255,255,0.18),
        rgba(0,100,255,0.08),
        transparent 70%);

    filter: blur(90px);

    z-index: 0;

    pointer-events: none;
}
.orbit-ring {
    position: absolute;

    top: 20%;
    left: 50%;

    transform: translateX(-50%);

    width: 500px;
    height: 500px;

    border: 1px solid rgba(255,255,255,0.08);

    border-radius: 50%;

    animation: rotateRing 40s linear infinite;
}
@keyframes rotateRing {
    from {
        transform: translateX(-50%) rotate(0deg);
    }

    to {
        transform: translateX(-50%) rotate(360deg);
    }
}
.matter-section {
    max-width: 700px;
    text-align: center;
    margin-top: 250px;
    margin: 20px auto;
    line-height: 1.8;
}
.particle-chain {
    display: flex;

    justify-content: center;
    gap: 40px;

    margin-top: 80px;
    margin-bottom: 60px;
}
.particle {
    width: 30px;
    height: 30px;

    border-radius: 50%;

    background: cyan;

    box-shadow: 0 0 20px cyan;

    transition: all 0.3s ease;
}
.particle.active {
    transform: scale(1.5);

    box-shadow:
        0 0 40px cyan,
        0 0 80px cyan;
}
.energy-button {

    margin-top: 30px;

    padding: 14px 32px;

    border: none;
    border-radius: 999px;

    background:
        linear-gradient(
            135deg,
            #67e8f9,
            #22d3ee
        );

    color: #031b2c;

    font-size: 1rem;
    font-weight: bold;

    cursor: pointer;

    transition: all 0.3s ease;

    box-shadow:
        0 0 20px rgba(34,211,238,0.5);

}
.energy-button:hover {

    transform: translateY(-4px) scale(1.05);

    box-shadow:
        0 0 35px rgba(34,211,238,0.8);

}
.space-energy-section {
    text-align: center;
    padding: 10rem 2rem;
}
.space-energy-section p {
    max-width: 750px;
    margin: 0 auto;
    line-height: 1.8;
}
.left-content {

    max-width: 700px;

    margin-left: 10%;

    text-align: left;
}
.light-content {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}
.space-wave-demo {

    display: flex;
    align-items: center;
    justify-content: center;

    gap: 0;

    margin-top: 50px;
}
.space-wave-source,
.space-wave-target {

    width: 35px;
    height: 35px;

    border-radius: 50%;

    background: #aaffff;

    box-shadow:
        0 0 10px #66ffff,
        0 0 20px #66ffff,
        0 0 40px #66ffff;
}
.space-wave-line {
    position: relative;
    width: 350px;
    height: 4px;
    overflow: hidden;

    border-radius: 20px;

    background: linear-gradient(
        90deg,
        transparent,
        #66ffff,
        transparent
    );

    background-size: 200% 100%;

    animation: waveFlow 3s linear;
    transform-origin: left center;
    transform: scaleX(0);
    transition: 0.3s ease;
}
@keyframes waveFlow {
    0% {
        transform: scaleX(0);
        opacity: 0;
    }

    15% {
        opacity: 1;
    }

    85% {
        opacity: 1;
    }

    100% {
        transform: scaleX(1);
        opacity: 0;
    }
}
.space-wave-pulse {

    position: absolute;

    top: -4px;
    left: -40px;

    width: 40px;
    height: 12px;

    border-radius: 20px;

    background: #66ffff;

    box-shadow:
        0 0 10px #66ffff,
        0 0 20px #66ffff,
        0 0 40px #66ffff;

    animation: moveSpaceWave 2s linear infinite;
}
.frequency-wave {

    width: 300px;
    height: 8px;

    border-radius: 20px;

    position: relative;

    overflow: hidden;

    background:
    rgba(0, 255, 255, 0.25);

    border:
    1px solid rgba(255,255,255,0.15);

    box-shadow:
    0 0 8px rgba(0,255,255,0.35);
}
.frequency-wave::after {

    content: "";

    position: absolute;

    top: 0;
    left: -30%;
    border-radius: inherit;

    width: 30%;
    height: 100%;

    background: white;
    box-shadow:
        0 0 10px rgba(255,255,255,0.5),
        0 0 18px rgba(0,255,255,0.35);

    animation: smoothWave 3s linear infinite;
}
.radio-wave::after {
    animation: smoothWave 6s linear infinite;
}
.microwave-wave::after {
    animation: smoothWave 4s linear infinite;
}
.infrared-wave::after {
    animation: smoothWave 3s linear infinite;
}
.uv-wave::after {
    animation: smoothWave 1.5s linear infinite;
}
.xray-wave::after {
    animation: smoothWave 1s linear infinite;
}
.gamma-wave::after {
    animation: smoothWave 0.5s linear infinite;
}
@keyframes smoothWave {

    from {
        left: -50%;
    }

    to {
        left: 120%;
    }
}
.spectrum-container {

    margin-top: 60px;
    padding-bottom: 100px;

    display: flex;
    flex-direction: column;

    align-items: center;

    gap: 25px;
}
.wave-label {

    display: flex;

    align-items: center;

    gap: 20px;
}
.wave-label span {

    width: 140px;

    text-align: right;

    font-weight: bold;

    color: white;
}
.gamma-wave {

    height: 4px;

    opacity: 1;
}
.radio-wave {

    height: 12px;

    opacity: 0.5;
}
.visible-wave {

    background:
    linear-gradient(
        90deg,
        red,
        orange,
        yellow,
        lime,
        cyan,
        blue,
        violet
    );
}
.visible-wave::after {

    background:
    linear-gradient(
        90deg,
        red,
        orange,
        yellow,
        cyan,
        blue,
        violet
    );

    animation:
    smoothWave 1.7s linear infinite;

    box-shadow:
    0 0 10px rgba(255,255,255,0.7),
    0 0 20px rgba(255,255,255,0.4);
}

/* ATOM SECTION */
body {
background: 
    radial-gradient(
        circle at 80% 20%,
        rgba(180, 0, 255, 0.18),
        transparent 30%
    ),

    radial-gradient(
        circle at 20% 80%,
        rgba(0, 120, 255, 0.12),
        transparent 35%
    ),

    radial-gradient(
        circle at center,
        rgba(0, 140, 255, 0.08),
        transparent 45%
    ),

    linear-gradient(
        180deg,
        #050816 0%,
        #091530 50%,
        #071120 100%
    );
}
body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;

    background-image:
        radial-gradient(white 1px, transparent 1px);

    background-size: 120px 120px;
    background-position:
    0 0 ,
    60px 40px;

    opacity: 0.18;
}
body::after {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;

    background-image:
        radial-gradient(white 1.5px, transparent 1.5px);

    background-size: 220px 220px;
    transform: rotate(20deg);

    opacity: 0.08;
}
@keyframes twinkle {
    0%, 100% {
        opacity: 0.7;
    }

    50% {
        opacity: 1;
    }
}
.atom-hero {
    min-height: 100vh;

    display: flex;
    align-items: center;
    justify-content: space-between;

    padding: 0 10%;

    background: transparent;
        

    color: white;
}
.atom-content {
    max-width: 500px;
    z-index: 2;
    animation: fadeUp 1.2s ease;
}
.atom-content h1 {
    font-size: 4rem;
    margin-bottom: 20px;
}
.atom-content p {
    font-size: 1.5rem;
    line-height: 1.6;
    opacity: 0.9;
}
.atom-content button {
    margin-top: 30px;

    padding: 16px 32px;

    border: none;
    border-radius: 14px;

    background: #ff4d6d;
    color: white;

    font-size: 1rem;
    font-weight: bold;

    cursor: pointer;

    box-shadow:
        0 0 20px rgba(255, 77, 109, 0.7);

    transition: 0.3s ease;
}
.atom-content button:hover {
    transform: scale(1.05);
}
.atom-visual {
    position: relative;
    transform-style: preserve-3d;

    width: 450px;
    height: 450px;

    display: flex;
    align-items: center;
    justify-content: center;
}
.nucleus {
    position: absolute;

    width: 90px;
    height: 90px;

    border-radius: 50%;

    background: radial-gradient(circle,
        #fff6b0,
        #ff4d6d);

    box-shadow:
        0 0 40px rgba(255, 77, 109, 0.9),
        0 0 100px rgba(255, 77, 109, 0.4);

    z-index: 5;
    animation: nucleusPulse 4s ease-in-out infinite;
}
.orbit {
    /* transform: translate(-50%, -50%); */
    top: 50%;
    left: 50%;
    position: absolute;

    border: 2px solid rgba(255,255,255,0.35);
    border-radius: 50%;

    display: flex;
    align-items: flex-start;
    justify-content: center;
    transform: rotateX(72deg);
    animation: spin 2s linear infinite;
}
.orbit-1 {
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 180px;
    height: 180px;
    animation-duration: 1s;}
.orbit-2 {
    width: 280px;
    height: 280px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);

    animation-duration: 2s;
}
.orbit-3 {
    width: 380px;
    height: 380px;

    animation-duration: 3s;
}
@keyframes spin {
    from {
        transform: rotate(0deg);
    }

    to {
        transform: rotate(360deg);
    }
}
@keyframes nucleusPulse {

    0% {
        transform: scale(1);
        box-shadow:
            0 0 40px rgba(255, 77, 109, 0.9),
            0 0 100px rgba(255, 77, 109, 0.4);
    }

    50% {
        transform: scale(1.08);
        box-shadow:
            0 0 60px rgba(255, 77, 109, 1),
            0 0 140px rgba(255, 77, 109, 0.7);
    }

    100% {
        transform: scale(1);
    }
}
@keyframes drift {
    from {
        transform: translate(0, 0);
    }

    to {
        transform: translate(-120px, -120px);
    }
}
@keyframes fadeUp {

    from {
        opacity: 0;
        transform: translateY(40px);
    }

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


/* ATOM INFO SECTION */

.atom-info-section {
    min-height: 100vh;

    display: flex;
    align-items: center;
    justify-content: space-between;

    gap: 100px;

    padding: 0 10%;

    color: white;
}
.atom-info-text {
    max-width: 600px;
}
.atom-info-text h2 {
    font-size: 2rem;
    margin-bottom: 30px;
}
.atom-info-text p {
    font-size: 1.3rem;
    line-height: 1.8;

    margin-bottom: 20px;

    opacity: 0.9;
}
.atom-info-visual {
    display: flex;
    align-items: center;
    justify-content: center;
}
.atom-breakdown {
    min-height: 100vh;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 180px 10%;
    position: relative;

    background: transparent;

}
.breakdown-left {
    width: 45%;
    z-index: 2;
}
.breakdown-left h2 {
    font-size: clamp(2rem, 6vw, 5rem);
    font-weight: 800;
    margin-bottom: 30px;
    color: white;
    line-height: 0.95;
}
.breakdown-left p {
    font-size: 1.2rem;
    line-height: 1.8;
    color: rgba(255,255,255,0.8);
    margin-bottom: 40px;
    max-width: 500px;
}
.particle-info {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
.info-card {
    background: rgba(255,255,255,0.05);
    border: 1px rgba(255,255,255,0.1);
    padding: 30px;
    border-radius: 20px;
    gap: 30px;

    backdrop-filter: blur(10px);

    transition: 0.4s ease;
}
.info-card:hover {
    transform: translateX(10px) translateY(-5px);
}
.info-card h3 {
    margin-bottom: 10px;
    font-size: 1.4rem;
}
.info-card p {
    margin: 0;
    font-size: 1rem;
}
.proton-card:hover {
    box-shadow: 0 0 25px rgba(255, 80, 80, 0.7);
}
.neutron-card:hover {
    box-shadow: 0 0 25px rgba(255,255,255,0.4);
}
.electron-card:hover {
    box-shadow: 0 0 25px rgba(0,255,255,0.7);
}
.breakdown-right {
    width: 45%;
    display: flex;
    justify-content: center;
    align-items: center;
}
.nucleus-card.active {
    border: 1px solid rgba(255, 120, 180, 0.8);

    box-shadow:
        0 0 20px rgba(255, 120, 180, 0.4),
        0 0 50px rgba(255, 120, 180, 0.2);

    transform: translateY(-5px);
}
@keyframes spin {
    from {
        transform: rotate(0deg);
    }

    to {
        transform: rotate(360deg);
    }
}
@keyframes spinReverse {
    from {
        transform: rotate(360deg);
    }

    to {
        transform: rotate(0deg);
    }
}

.atom-breakdown::before {
    content: "";

    position: absolute;

    top: 0;
    left: 50%;

    transform: translateX(-50%);

    width: 70%;
    height: 1px;

    background: linear-gradient(
        to right,
        transparent,
        rgba(0,255,255,0.5),
        transparent
    );
}
.particle-highlight {
    transform: scale(1.1);
    filter: brightness(1.4);
    transition: all 0.3s ease;
}
.atom-card {
    cursor: pointer;
    transition: 0.3s ease;
}
.atom-card:hover {

    transform: translateY(-5px);

    box-shadow:
        0 0 20px rgba(255,255,255,0.2);
}
@keyframes particlePulse {

    from {
        transform: scale(1.2);
        opacity: 0.7;
    }

    to {
        transform: scale(1.7);
        opacity: 1;
    }
}
.proton,
.neutron {
    position: absolute;
    z-index: 5;
}
.proton-highlight,
.neutron-highlight,
.particle-highlight {
    transform: scale(1.15);
    color:#fff6b0;
    
    transition: all 0.3s ease;
}
@keyframes protonPulse {

    from {
        transform: scale(1);
    }

    to {
        transform: scale(1.15);
    }

}
@keyframes neutronPulse {

    from {
        opacity: 0.7;
        transform: scale(1);
    }

    to {
        opacity: 1;
        transform: scale(1.08);
    }

}
.nucleus-proton,
.nucleus-neutron {

    position: absolute;
    animation: nucleusFloat 3s ease-in-out infinite;

    width: 22px;
    height: 22px;

    border-radius: 50%;
    background: radial-gradient(circle,
        #fff6b0,
        #ff4d6d);
    box-shadow:
        0 0 40px rgba(255, 77, 109, 0.9),
        0 0 100px rgba(255, 77, 109, 0.4);
}
.proton-2 {

    top: 45%;
    left: 55%;

}
.neutron-2 {

    top: 55%;
    left: 40%;

}
.nucleus-proton {

    top: 35%;
    left: 35%;
    animation-delay: 0s;
    z-index: 2;

}
.nucleus-neutron {

    top: 50%;
    left: 50%;
    animation-delay: 1.2s;
    z-index: 2;

}
@keyframes nucleusFloat {

    0% {
        transform: translateY(0px);
    }

    50% {
        transform: translateY(-4px);
    }

    100% {
        transform: translateY(0px);
    }

}
.proton-highlight {
    background:#fff6b0;


    transform: scale(1.4);

}
.neutron-highlight {
    background: #fff6b0;
    transform: scale(1.4);

}
.nucleus-card {
    background: rgba(255,255,255,0.05);
    border: 1px rgba(255,255,255,0.1);
    padding: 30px;
    border-radius: 20px;
    gap: 30px;

    backdrop-filter: blur(10px);

    transition: 0.4s ease;
}
.nucleus-card:hover {
    transform: translateX(10px) translateY(-5px);
}
.nucleus-card h3 {
    margin-bottom: 10px;
    font-size: 1.4rem;
}
.demo-nucleus {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 120px;
    height: 120px;
    transform: translate(-50%, -50%);}
.demo-nucleus::before {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: 50%;

    background: radial-gradient(circle,
        #fff6b0,
        #ff4d6d);

    box-shadow:
        0 0 40px rgba(255, 77, 109, 0.9),
        0 0 100px rgba(255, 77, 109, 0.4);

    z-index: 1;
    animation: nucleusPulse 4s ease-in-out infinite;
}

.atom-demo {
    position: relative;
    width: 400px;
    height: 400px;
}

/* .demo-orbit {
    position: absolute;
    top: 50%;
    left: 50%;

    width: 260px;
    height: 260px;

    border: 2px solid cyan;
    border-radius: 50%;

    transform: translate(-50%, -50%);
}
*/