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

body {
    background-color: #121212;
    color: #e0e0e0;
    font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
    line-height: 1.8;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background: radial-gradient(circle at center, #1a1a1a 0%, #0a0a0a 100%);
    overflow: hidden;
}

.bg-effects {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    overflow: hidden;
}

.aurora {
    position: absolute;
    bottom: -10vh;
    left: -20%;
    width: 140%;
    height: 40vh;
    background: radial-gradient(ellipse at bottom, rgba(180, 180, 180, 0.15) 0%, rgba(180, 180, 180, 0) 70%);
    filter: blur(40px);
    animation: auroraFloat 12s infinite alternate ease-in-out;
}

.aurora-2 {
    position: absolute;
    bottom: -15vh;
    left: -10%;
    width: 120%;
    height: 30vh;
    background: radial-gradient(ellipse at bottom, rgba(220, 220, 220, 0.1) 0%, rgba(220, 220, 220, 0) 60%);
    filter: blur(50px);
    animation: auroraFloat2 15s infinite alternate ease-in-out;
}

@keyframes auroraFloat {
    0% {
        transform: translateX(-5%) scaleY(1);
        opacity: 0.8;
    }

    100% {
        transform: translateX(5%) scaleY(1.3);
        opacity: 1;
    }
}

@keyframes auroraFloat2 {
    0% {
        transform: translateX(5%) scaleY(1.1);
        opacity: 1;
    }

    100% {
        transform: translateX(-5%) scaleY(0.9);
        opacity: 0.7;
    }
}

.rising-circle {
    position: absolute;
    bottom: -200px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(200, 200, 200, 0.15) 0%, rgba(200, 200, 200, 0) 60%);
    animation: riseUp 10s linear infinite;
}

.circle-1 {
    left: 10%;
    width: 150px;
    height: 150px;
    animation-duration: 12s;
    animation-delay: 0s;
}

.circle-2 {
    left: 30%;
    width: 80px;
    height: 80px;
    animation-duration: 8s;
    animation-delay: 2s;
}

.circle-3 {
    left: 50%;
    width: 200px;
    height: 200px;
    animation-duration: 15s;
    animation-delay: 4s;
}

.circle-4 {
    left: 70%;
    width: 120px;
    height: 120px;
    animation-duration: 11s;
    animation-delay: 1s;
}

.circle-5 {
    left: 85%;
    width: 60px;
    height: 60px;
    animation-duration: 7s;
    animation-delay: 3s;
}

.circle-6 {
    left: 20%;
    width: 100px;
    height: 100px;
    animation-duration: 13s;
    animation-delay: 6s;
}

.circle-7 {
    left: 60%;
    width: 50px;
    height: 50px;
    animation-duration: 9s;
    animation-delay: 7s;
}

@keyframes riseUp {
    0% {
        transform: translateY(0) scale(0.8);
        opacity: 0;
    }

    20% {
        opacity: 1;
    }

    80% {
        opacity: 1;
    }

    100% {
        transform: translateY(-120vh) scale(1.2);
        opacity: 0;
    }
}

.nav-bar {
    padding: 1.5rem 2rem;
    display: flex;
    align-items: center;
    position: relative;
    z-index: 10;
}

.back-link {
    color: #999;
    text-decoration: none;
    font-size: 0.95rem;
    padding: 0.5rem 1rem;
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 20px;
    transition: all 0.3s ease;
    background-color: rgba(255, 255, 255, 0.03);
}

.back-link:hover {
    color: #fff;
    border-color: rgba(255, 255, 255, 0.4);
    background-color: rgba(255, 255, 255, 0.08);
}

.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    text-align: center;
    position: relative;
    z-index: 10;
}

h1 {
    font-size: 2.5rem;
    font-weight: 300;
    letter-spacing: 0.15em;
    margin-bottom: 1rem;
    color: #f0f0f0;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
}

.subtitle {
    font-size: 1rem;
    color: #777;
    letter-spacing: 0.08em;
    margin-bottom: 3rem;
}

.placeholder-box {
    max-width: 600px;
    width: 100%;
    padding: 3rem 2rem;
    background-color: rgba(255, 255, 255, 0.02);
    border: 1px dashed rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    backdrop-filter: blur(10px);
}

.placeholder-box p {
    color: #888;
    font-size: 0.95rem;
    margin-bottom: 1rem;
}

.placeholder-box p:last-child {
    margin-bottom: 0;
}

.footer {
    padding: 2rem;
    text-align: center;
    font-size: 0.8rem;
    color: #555;
    position: relative;
    z-index: 10;
}

.intro-overlay {
    position: fixed;
    inset: 0;
    z-index: 99999;
    display: flex;
    justify-content: center;
    align-items: center;
    pointer-events: none;
}

.intro-bg {
    position: absolute;
    inset: 0;
    background-color: #000;
    transition: background-color 1.5s cubic-bezier(0.4, 0, 0.2, 1),
        box-shadow 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.intro-text {
    position: relative;
    z-index: 1;
    text-align: center;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 1s ease, transform 1s ease;
}

.intro-text h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 300;
    letter-spacing: 0.25em;
    margin-bottom: 1.5rem;
    color: #ffffff;
    transition: color 1.5s cubic-bezier(0.4, 0, 0.2, 1),
        text-shadow 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.intro-text p {
    font-size: clamp(0.9rem, 2vw, 1.2rem);
    letter-spacing: 0.15em;
    color: #aaaaaa;
    transition: color 1.5s cubic-bezier(0.4, 0, 0.2, 1),
        text-shadow 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.intro-overlay.show-text .intro-text {
    opacity: 1;
    transform: translateY(0);
}

.intro-overlay.bright .intro-bg {
    background-color: #ECFFFF;
}

.intro-overlay.bright .intro-text h1,
.intro-overlay.bright .intro-text p {
    color: #000000;
    text-shadow: none;
}

.intro-overlay.glare .intro-bg {
    background-color: #ffffff;
    box-shadow: inset 0 0 60vw rgba(255, 255, 255, 1);
    transition: background-color 1.5s cubic-bezier(0.4, 0, 0.2, 1),
        box-shadow 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.intro-overlay.glare .intro-text h1,
.intro-overlay.glare .intro-text p {
    color: #ffffff;
    text-shadow: 0 0 20px rgba(255, 255, 255, 1),
        0 0 50px rgba(255, 255, 255, 1),
        0 0 80px rgba(255, 255, 255, 1);
    transition: color 1.5s cubic-bezier(0.4, 0, 0.2, 1),
        text-shadow 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.intro-overlay.fade-out {
    transition: opacity 1.0s ease;
    opacity: 0;
}