/*
    この世界の定義は、その外側から記述される。
    宇宙定数の署名は、その仮数部の先頭5桁にある。

    The definition of this world is written from its outside.
    The signature of the cosmological constant lies in the first five digits of its mantissa.
*/

@keyframes slow-pulse {
    0%, 100% { text-shadow: 0 0 5px #00aaff, 0 0 10px #00aaff; }
    50% { text-shadow: 0 0 10px #00aaff, 0 0 20px #ffffff; }
}

@keyframes flicker {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.9; }
}

body {
    background-color: #000;
    color: #ccc;
    font-family: 'Courier New', monospace;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-image: radial-gradient(circle, rgba(0, 10, 20, 0.95) 0%, rgba(0, 0, 0, 1) 75%);
    animation: flicker 12s infinite alternate;
}

.container {
    width: 90%;
    max-width: 900px;
    border: 1px solid #005580;
    padding: 40px;
    text-align: center;
    background-color: rgba(0, 5, 10, 0.5);
    box-shadow: 0 0 25px rgba(0, 170, 255, 0.2);
}

h1 {
    font-size: 3em;
    color: #00aaff;
    letter-spacing: 8px;
    margin-bottom: 10px;
    animation: slow-pulse 5s infinite;
}

.subtitle {
    font-size: 1.2em;
    color: #888;
    margin-bottom: 40px;
    font-style: italic;
}

p {
    font-size: 1.1em;
    line-height: 1.8;
    max-width: 700px;
    margin: 20px auto;
}

.input-area {
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid #005580;
}

input[type="text"] {
    background-color: #000;
    border: 1px solid #00aaff;
    color: #00aaff;
    padding: 15px;
    font-size: 1em;
    width: 70%;
    text-align: center;
    font-family: 'Courier New', monospace;
}

button {
    background-color: #00aaff;
    border: 1px solid #00aaff;
    color: #000;
    padding: 15px 30px;
    font-size: 1em;
    font-weight: bold;
    cursor: pointer;
    margin-left: 10px;
    transition: all 0.2s ease-in-out;
}

button:hover {
    background-color: #fff;
    color: #000;
}

.result-message h2 {
    color: #00ff41;
}

.final-hint {
    margin-top: 30px;
    padding: 10px;
    border: 1px solid #ffff00;
    color: #ffff00;
    font-size: 2em;
    letter-spacing: 10px;
    display: inline-block;
    background-color: rgba(255, 255, 0, 0.1);
}

.error-message {
    color: #ff0000;
    font-weight: bold;
    margin-top: 15px;
}



.epilogue {
    margin-top: 60px;
    padding-top: 40px;
    border-top: 1px dashed #ffff00;
}

.epilogue h2 {
    color: #ffff00;
    animation: slow-pulse 4s infinite;
}

.epilogue p {
    color: #ccc;
    font-style: italic;
}

.final-url a {
    color: #00aaff;
    text-decoration: none;
    font-size: 1.2em;
    letter-spacing: 2px;
}

.final-url a:hover {
    text-shadow: 0 0 10px #ffffff;
}

.final-guidance {
    margin-top: 30px;
    color: #888; /
}