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

body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: #181a20;
    color: #e0e0e0;
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
}

.container {
    max-width: 1180px;
    margin: 0 auto;
    padding: 0 24px;
}

.echo-header {
    background-color: #23252e;
    border-bottom: 1px solid rgba(39, 119, 255, 0.15);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(8px);
}

.logo {
    display: flex;
    align-items: center;
    gap: 14px;
    font-size: 1.55rem;
    font-weight: 700;
    letter-spacing: 1.5px;
}

.logo-echo {
    color: #2777ff;
    letter-spacing: 3px;
}

.logo-matter {
    color: #bbbbbb;
}

.mirrors {
    margin-top: 8px;
    font-size: 0.93rem;
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.mirrors-label {
    color: #777;
    white-space: nowrap;
}

.mirror-link {
    color: #2777ff;
    text-decoration: none;
    transition: color 0.2s ease;
}

.mirror-link:hover {
    color: #5a9eff;
}

.void-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: radial-gradient(circle at 50% 40%, #23252e 0%, #181a20 70%);
    position: relative;
}

.void-content {
    max-width: 820px;
    padding: 0 20px;
}

.void-title {
    font-size: clamp(2.8rem, 6vw, 3.8rem);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 24px;
    color: #ffffff;
    letter-spacing: -1.2px;
}

.void-subtitle {
    font-size: 1.32rem;
    color: #bbbbbb;
    margin-bottom: 48px;
    max-width: 680px;
    margin-left: auto;
    margin-right: auto;
}

.btn-primary, .btn-secondary {
    display: inline-block;
    padding: 16px 38px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.02rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    margin: 0 10px;
}

.btn-primary {
    background-color: #2777ff;
    color: #fff;
}

.btn-primary:hover {
    background-color: #1e5fd9;
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(39, 119, 255, 0.3);
}

.btn-secondary {
    background-color: transparent;
    color: #2777ff;
    border: 1.5px solid #2777ff;
}

.btn-secondary:hover {
    background-color: rgba(39, 119, 255, 0.08);
    transform: translateY(-3px);
}

.archive-nav {
    background-color: #23252e;
    padding: 20px 0;
    border-bottom: 1px solid rgba(51, 51, 51, 0.8);
    position: sticky;
    top: 73px;
    z-index: 99;
    backdrop-filter: blur(8px);
}

.nav-item {
    color: #aaaaaa;
    text-decoration: none;
    margin: 0 24px;
    font-size: 1rem;
    font-weight: 500;
    transition: all 0.2s ease;
    position: relative;
}

.nav-item:hover {
    color: #2777ff;
}

.nav-item:after {
    content: '';
    position: absolute;
    width: 0;
    height: 1px;
    bottom: -4px;
    left: 0;
    background-color: #2777ff;
    transition: width 0.3s ease;
}

.nav-item:hover:after {
    width: 100%;
}

.echo-section {
    padding: 120px 0;
    border-bottom: 1px solid #23252e;
}

.section-header {
    display: flex;
    align-items: center;
    gap: 28px;
    margin-bottom: 56px;
    padding: 0 20px;
}

.section-number {
    font-size: 1.25rem;
    color: #2777ff;
    font-weight: 700;
    letter-spacing: 4px;
    flex-shrink: 0;
}

.section-header h2 {
    font-size: 2.35rem;
    font-weight: 600;
    line-height: 1.25;
    color: #f0f0f0;
}

.image-container {
    max-width: 1180px;
    margin: 0 auto 68px;
    padding: 12px;
    border: 1px solid rgba(39, 119, 255, 0.18);
    background-color: #1c1f27;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.echo-image {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 4px;
    transition: transform 0.6s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.echo-image:hover {
    transform: scale(1.025);
}

.description {
    max-width: 860px;
    margin: 0 auto;
    padding: 0 24px;
    font-size: 1.1rem;
    color: #d0d0d0;
}

.description p {
    margin-bottom: 22px;
}

.description ul {
    margin: 24px 0 24px 32px;
    list-style: none;
}

.description li {
    position: relative;
    margin-bottom: 14px;
    padding-left: 8px;
}

.description li:before {
    content: '•';
    color: #2777ff;
    position: absolute;
    left: -18px;
}

.echo-footer {
    background-color: #181a20;
    padding: 90px 0 60px;
    text-align: center;
    border-top: 1px solid #23252e;
}

.footer-text {
    color: #888888;
    font-size: 1.02rem;
    max-width: 820px;
    margin: 0 auto 48px;
    line-height: 1.75;
}

.footer-mirrors {
    font-size: 0.97rem;
    color: #666666;
    margin-bottom: 32px;
}

.mirror-link-small {
    display: inline-block;
    margin: 8px 16px;
    word-break: break-all;
    color: #2777ff;
    font-size: 0.95rem;
}

.status-info {
    color: #999999;
    font-size: 1rem;
}

.status {
    color: #33ff66;
    font-weight: 700;
}

@media (max-width: 768px) {
    .container {
        padding: 0 18px;
    }
    
    .echo-header {
        padding: 16px 0;
    }
    
    .logo {
        font-size: 1.4rem;
    }
    
    .mirrors {
        gap: 8px;
        font-size: 0.88rem;
    }
    
    .void-subtitle {
        font-size: 1.18rem;
    }
    
    .btn-primary, .btn-secondary {
        display: block;
        margin: 12px auto;
        max-width: 280px;
    }
    
    .nav-item {
        display: block;
        margin: 16px 0;
        text-align: center;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    
    .section-header h2 {
        font-size: 2rem;
    }
    
    .echo-section {
        padding: 90px 0;
    }
    
    .description {
        font-size: 1.05rem;
    }
}

.echo-header {
    background-color: #23252e;
    border-bottom: 1px solid rgba(39, 119, 255, 0.15);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(8px);
}

.logo {
    display: flex;
    align-items: center;
    gap: 14px;
    font-size: 1.55rem;
    font-weight: 700;
    letter-spacing: 1.5px;
}

.logo-echo {
    color: #2777ff;
    letter-spacing: 3px;
}

.logo-matter {
    color: #bbbbbb;
}

.mirrors {
    margin-top: 8px;
    font-size: 0.93rem;
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.mirrors-label {
    color: #777;
    white-space: nowrap;
}

.mirror-link {
    color: #2777ff;
    text-decoration: none;
    transition: color 0.2s ease;
}

.mirror-link:hover {
    color: #5a9eff;
}

.void-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: radial-gradient(circle at 50% 40%, #23252e 0%, #181a20 70%);
    position: relative;
}

.void-content {
    max-width: 820px;
    padding: 0 20px;
}

.void-title {
    font-size: clamp(2.8rem, 6vw, 3.8rem);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 24px;
    color: #ffffff;
    letter-spacing: -1.2px;
}

.void-subtitle {
    font-size: 1.32rem;
    color: #bbbbbb;
    margin-bottom: 48px;
    max-width: 680px;
    margin-left: auto;
    margin-right: auto;
}

.btn-primary, .btn-secondary {
    display: inline-block;
    padding: 16px 38px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.02rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    margin: 0 10px;
}

.btn-primary {
    background-color: #2777ff;
    color: #fff;
}

.btn-primary:hover {
    background-color: #1e5fd9;
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(39, 119, 255, 0.3);
}

.btn-secondary {
    background-color: transparent;
    color: #2777ff;
    border: 1.5px solid #2777ff;
}

.btn-secondary:hover {
    background-color: rgba(39, 119, 255, 0.08);
    transform: translateY(-3px);
}

.archive-nav {
    background-color: #23252e;
    padding: 20px 0;
    border-bottom: 1px solid rgba(51, 51, 51, 0.8);
    position: sticky;
    top: 73px;
    z-index: 99;
    backdrop-filter: blur(8px);
}

.nav-item {
    color: #aaaaaa;
    text-decoration: none;
    margin: 0 24px;
    font-size: 1rem;
    font-weight: 500;
    transition: all 0.2s ease;
    position: relative;
}

.nav-item:hover {
    color: #2777ff;
}

.nav-item:after {
    content: '';
    position: absolute;
    width: 0;
    height: 1px;
    bottom: -4px;
    left: 0;
    background-color: #2777ff;
    transition: width 0.3s ease;
}

.nav-item:hover:after {
    width: 100%;
}

.echo-section {
    padding: 120px 0;
    border-bottom: 1px solid #23252e;
}

.section-header {
    display: flex;
    align-items: center;
    gap: 28px;
    margin-bottom: 56px;
    padding: 0 20px;
}

.section-number {
    font-size: 1.25rem;
    color: #2777ff;
    font-weight: 700;
    letter-spacing: 4px;
    flex-shrink: 0;
}

.section-header h2 {
    font-size: 2.35rem;
    font-weight: 600;
    line-height: 1.25;
    color: #f0f0f0;
}

.image-container {
    max-width: 1180px;
    margin: 0 auto 68px;
    padding: 12px;
    border: 1px solid rgba(39, 119, 255, 0.18);
    background-color: #1c1f27;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.echo-image {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 4px;
    transition: transform 0.6s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.echo-image:hover {
    transform: scale(1.025);
}

.description {
    max-width: 860px;
    margin: 0 auto;
    padding: 0 24px;
    font-size: 1.1rem;
    color: #d0d0d0;
}

.description p {
    margin-bottom: 22px;
}

.description ul {
    margin: 24px 0 24px 32px;
    list-style: none;
}

.description li {
    position: relative;
    margin-bottom: 14px;
    padding-left: 8px;
}

.description li:before {
    content: '•';
    color: #2777ff;
    position: absolute;
    left: -18px;
}

.echo-footer {
    background-color: #181a20;
    padding: 90px 0 60px;
    text-align: center;
    border-top: 1px solid #23252e;
}

.footer-text {
    color: #888888;
    font-size: 1.02rem;
    max-width: 820px;
    margin: 0 auto 48px;
    line-height: 1.75;
}

.footer-mirrors {
    font-size: 0.97rem;
    color: #666666;
    margin-bottom: 32px;
}

.mirror-link-small {
    display: inline-block;
    margin: 8px 16px;
    word-break: break-all;
    color: #2777ff;
    font-size: 0.95rem;
}

.status-info {
    color: #999999;
    font-size: 1rem;
}

.status {
    color: #33ff66;
    font-weight: 700;
}

@media (max-width: 768px) {
    .container {
        padding: 0 18px;
    }
    
    .echo-header {
        padding: 16px 0;
    }
    
    .logo {
        font-size: 1.4rem;
    }
    
    .mirrors {
        gap: 8px;
        font-size: 0.88rem;
    }
    
    .void-subtitle {
        font-size: 1.18rem;
    }
    
    .btn-primary, .btn-secondary {
        display: block;
        margin: 12px auto;
        max-width: 280px;
    }
    
    .nav-item {
        display: block;
        margin: 16px 0;
        text-align: center;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    
    .section-header h2 {
        font-size: 2rem;
    }
    
    .echo-section {
        padding: 90px 0;
    }
    
    .description {
        font-size: 1.05rem;
    }
}