@charset "UTF-8";

:root {
    --background: linear-gradient(135deg, #cfc 75%, #ffc 100%);
    --text-color: #2c3e50;
    --header-text-color: #2c3e50;
    --header-title-color-hover: #cfc;
    --header-text-color-hover: #2c3e50;
    --primary: #6c9;
    --secondary: #cfc;
    --content-background: #efd;
    --content-border: #e9ecef;
    --content-background-hover: #f8f9fa;
    
    --content-border-internal: #2c3e50;
}
/* #f4f3f9 #92cb97 */
/* :root {
    --background: #f4f2db;
    --text-color: #424f56;
    --header-text-color: #f4f2db;
    --header-text-color-hover: #171418;
    --header-title-color-hover: #6cb2d3;
    --primary: #1d4b69;
    --secondary: #6cb2d3;
    --content-background: rgb(252, 249, 223);
    --content-border: #424f56;
    --content-background-hover: #d7eef8;
} */

/* :root {
    --background: linear-gradient(135deg, #cfc 75%, #ffc 100%);
    --text-color: #2c3e50;
    --primary: rgb(255, 61, 103);
    --secondary: #cfc;
} */

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

body {
    font-family: 'Hiragino Sans', 'Yu Gothic', 'Meiryo', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: var(--background);
    min-height: 100vh;
}

.title-section {
    font-size: 50px;
}

img {
    image-rendering: pixelated;
}

ol {
    padding-left: 0.5em;
}

ol li {
    list-style-type: decimal; /* or 'decimal-leading-zero', 'upper-alpha', 'lower-alpha'... */
    list-style-position: outside; /* or 'inside' */
    margin-left: 1em; /* gives 'room' for the numbers to appear in */
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 70px;
    background: var(--primary);
    border-bottom: 1px solid var(--content-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
    z-index: 1000;
    transition: all 0.3s ease;
}

.header-title {
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--header-text-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

.header-title:hover {
    color: var(--header-title-color-hover);
}

.header-navigation {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.header-navigation a {
    color: var(--header-text-color);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    position: relative;
}

.header-navigation a:hover {
    background: var(--secondary);
    color: var(--header-text-color-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(52, 152, 219, 0.3);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-color);
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 2px;
}

.contents {
    margin-top: 70px;
    padding: 3rem 2rem;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
}

.content-section {
    /* text-align: center;
    padding: 2rem 0; */
    text-align: left;
    padding: 1rem 1rem;
    background: var(--content-background);
    border-radius: 12px;
    border: 1px solid var(--content-border);
    width: 100%;
    max-width: 800px;
    /* margin-bottom: 2rem; */
}

.content-section h1 {
    font-size: 2.5rem;
    color: var(--text-color);
    margin-bottom: 1rem;
}

.image-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    margin: 2rem 0;
}

.image-container img {
    border-radius: 8px;
    border: 1px solid var(--content-border);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.image-container img:hover {
    transform: scale(1.02);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
}

.image-container img:first-child {
    width: 200px;
    height: auto;
}

.image-container img:last-child {
    width: 80%;
    max-width: 600px;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .header {
        padding: 0 1rem;
        height: 60px;
    }

    .header-title {
        font-size: 1.5rem;
    }

    .title-section {
        font-size: 2rem;
    }

    .header-navigation {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        gap: 0;
        background: var(--primary);
        border-bottom: 1px solid var(--content-border);
        flex-direction: column;
        padding: 1rem;
    }

    .header-navigation.active {
        display: flex;
    }

    .header-navigation a {
        width: 100%;
        text-align: center;
        padding: 0.5rem;
        margin: 0.5rem 0;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(-45deg) translate(-5px, 6px);
    }

    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(45deg) translate(-5px, -6px);
    }

    .contents {
        margin-top: 60px;
        padding: 2rem 1rem;
    }

    .hero-section h1 {
        font-size: 2rem;
    }

    .image-container img:last-child {
        width: 95%;
    }

    .update-history {
        padding: 1.5rem;
    }
    .hide-on-mobile {
        display: None;
    }
}

@media (max-width: 480px) {
    .hero-section h1 {
        font-size: 1.8rem;
    }

    .header-title {
        font-size: 1.3rem;
    }

    .title-section {
        font-size: 1.5rem;
    }

    .image-container img:first-child {
        width: 150px;
    }
    .hide-on-mobile {
        display: None;
    }
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.contents > * {
    animation: fadeInUp 0.6s ease forwards;
}

.contents > *:nth-child(2) {
    animation-delay: 0.2s;
}

.contents > *:nth-child(3) {
    animation-delay: 0.4s;
}

.contents > *:nth-child(4) {
    animation-delay: 0.6s;
}

.centered-img-container {
    display: flex;
    align-items: center;
    width: 100%;
    justify-content: center;
    flex-direction: column;
}