.ndias-ctf-wrap {
    position: relative;
    overflow: hidden;
    max-width: 860px;
    margin: 0 auto;
    padding: 4vh 16px 40px;
    color: inherit;
    text-align: center;
}

.ndias-ctf-wrap>* {
    position: relative;
    z-index: 1;
}

.ndias-wordmark {
    position: absolute;
    top: -18px;
    left: 50%;
    z-index: 0;
    transform: translateX(-50%);
    font-size: clamp(4.5rem, 16vw, 11rem);
    font-weight: 900;
    letter-spacing: .18em;
    line-height: .9;
    text-transform: uppercase;
    white-space: nowrap;
    pointer-events: none;
    user-select: none;
    opacity: .07;
    color: var(--theme-color, #2d5fb8);
}

body.theme-dark .ndias-wordmark,
html[data-bs-theme="dark"] .ndias-wordmark,
body[data-bs-theme="dark"] .ndias-wordmark,
body.dark .ndias-wordmark {
    opacity: .12;
    color: #93c5fd;
}

.ndias-ctf-banner {
    display: block;
    width: 100%;
    max-width: 500px;
    margin: 0 auto 28px;
}

.ndias-ctf-countdown {
    margin: 50px auto 40px;
    max-width: 760px;
}

.ndias-ctf-countdown-label {
    margin-bottom: 14px;
    font-size: 1.35rem;
    font-weight: 600;
    opacity: .9;
    letter-spacing: .02em;
}

.ndias-ctf-countdown-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(90px, 1fr));
    gap: 14px;
}

.ndias-ctf-timebox {
    padding: 14px 10px 12px;
    border-radius: 14px;
    border: 1px solid rgba(127, 127, 127, .22);
    background: rgba(127, 127, 127, .06);
}

.ndias-ctf-time-value {
    display: block;
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
    font-size: clamp(2.2rem, 4.5vw, 3.1rem);
    font-weight: 800;
    line-height: 1;
    letter-spacing: .04em;
}

.ndias-ctf-time-label {
    display: block;
    margin-top: 8px;
    font-size: .9rem;
    opacity: .75;
    letter-spacing: .08em;
}

.ndias-ctf-status {
    margin-top: 16px;
    font-size: 1.08rem;
    opacity: .82;
}

.ndias-ctf-presented {
    margin: 50px 0 10px;
    font-size: 1.2rem;
}

.ndias-ctf-wrap a {
    color: var(--theme-color, #2d5fb8);
    text-decoration: underline;
    text-underline-offset: .18em;
    text-decoration-thickness: .08em;
}

.ndias-ctf-presented a {
    font-weight: 700;
}

.ndias-ctf-socials a,
.ndias-ctf-login {
    color: inherit;
    text-decoration: none;
}

.ndias-ctf-social-title {
    margin: 0 0 14px;
    font-size: 1.15rem;
    opacity: .9;
}

.ndias-ctf-socials {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 16px;
    margin: 0 0 30px;
}

.ndias-ctf-socials a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 62px;
    height: 62px;
    border-radius: 14px;
    background: rgba(127, 127, 127, .06);
    border: 1px solid rgba(127, 127, 127, .18);
    transition: transform .15s ease, background .15s ease, border-color .15s ease, opacity .15s ease;
}

.ndias-ctf-socials a:hover {
    transform: translateY(-2px);
    background: rgba(127, 127, 127, .12);
    border-color: rgba(127, 127, 127, .28);
    color: inherit;
    text-decoration: none;
}

.ndias-ctf-login {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 24px;
    border-radius: 12px;
    border: 1px solid rgba(127, 127, 127, .24);
    background: rgba(127, 127, 127, .08);
    font-size: 1.15rem;
    font-weight: 700;
    transition: transform .15s ease, background .15s ease, border-color .15s ease;
}

.ndias-ctf-login:hover {
    transform: translateY(-1px);
    background: rgba(127, 127, 127, .14);
    border-color: rgba(127, 127, 127, .32);
    color: inherit;
    text-decoration: none;
}

.ndias-ctf-auth {
    margin-top: 18px;
}

.ndias-ctf-auth-title {
    margin: 0 0 14px;
    font-size: 1.1rem;
    font-weight: 700;
}

.ndias-ctf-auth-actions {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 12px;
}

.ndias-ctf-auth-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 180px;
    padding: 14px 24px;
    border-radius: 12px;
    border: 1px solid rgba(127, 127, 127, .24);
    background: rgba(127, 127, 127, .08);
    color: inherit;
    font-size: 1.05rem;
    font-weight: 700;
    text-decoration: none;
    transition: transform .15s ease, background .15s ease, border-color .15s ease;
}

.ndias-ctf-auth-button:hover {
    transform: translateY(-1px);
    background: rgba(127, 127, 127, .14);
    border-color: rgba(127, 127, 127, .32);
    color: inherit;
    text-decoration: none;
}

@media (max-width:640px) {
    .ndias-ctf-wrap {
        padding-top: 28px;
    }

    .ndias-wordmark {
        top: 8px;
        font-size: clamp(3rem, 18vw, 5.8rem);
        letter-spacing: .12em;
    }

    .ndias-ctf-countdown-grid {
        grid-template-columns: repeat(2, minmax(100px, 1fr));
    }

    .ndias-ctf-auth-actions {
        flex-direction: column;
    }

    .ndias-ctf-auth-button,
    .ndias-ctf-login {
        width: 100%;
    }
}

/* Rules page */

#rules-page {
    --rules-border: rgba(15, 23, 42, .10);
    --rules-page-bg: transparent;
    --rules-card-bg: rgba(255, 255, 255, .88);
    --rules-card-bg-strong: rgba(255, 255, 255, .96);
    --rules-soft: rgba(15, 23, 42, .05);
    --rules-soft-strong: rgba(15, 23, 42, .08);
    --rules-text: #0f172a;
    --rules-muted: #475569;
    --rules-accent: var(--theme-color, #2d5fb8);
    --rules-link: var(--theme-color, #2d5fb8);
    --rules-shadow: 0 18px 48px rgba(15, 23, 42, .08);
    color: var(--rules-text);
    line-height: 1.7;
}

body.theme-dark #rules-page,
html[data-bs-theme="dark"] #rules-page,
body[data-bs-theme="dark"] #rules-page,
body.dark #rules-page {
    --rules-border: rgba(255, 255, 255, .10);
    --rules-page-bg: transparent;
    --rules-card-bg: rgba(15, 23, 42, .76);
    --rules-card-bg-strong: rgba(15, 23, 42, .88);
    --rules-soft: rgba(255, 255, 255, .06);
    --rules-soft-strong: rgba(255, 255, 255, .10);
    --rules-text: #f8fafc;
    --rules-muted: rgba(226, 232, 240, .84);
    --rules-shadow: 0 18px 48px rgba(0, 0, 0, .34);
}

#rules-page * {
    box-sizing: border-box;
}

#rules-page a {
    color: inherit;
    text-decoration: none;
}

#rules-page .ndias-rules-wrap {
    position: relative;
    overflow: hidden;
    max-width: 1120px;
    margin: 0 auto;
    padding-top: 28px;
    text-align: left;
}

#rules-page .ndias-wordmark {
    left: 26px;
    top: -4px;
    transform: none;
    font-size: clamp(4rem, 12vw, 8rem);
    letter-spacing: .16em;
    text-align: left;
}

#rules-page .rules-hero {
    margin-bottom: 18px;
}

#rules-page .rules-hero-card {
    border: 1px solid var(--rules-border);
    background: var(--rules-card-bg);
    border-radius: 24px;
    padding: 24px;
    box-shadow: var(--rules-shadow);
    backdrop-filter: blur(12px);
}

#rules-page .rules-hero-top {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 18px;
    margin-bottom: 18px;
}

#rules-page .rules-kicker {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    padding: 6px 12px;
    border: 1px solid var(--rules-border);
    border-radius: 999px;
    background: var(--rules-soft);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: .04em;
    text-transform: uppercase;
}

#rules-page .rules-title {
    margin: 0 0 10px;
    font-size: clamp(2rem, 4vw, 3rem);
    line-height: 1.08;
}

#rules-page .rules-desc,
#rules-page .rules-desc .copy {
    margin: 0;
    max-width: 760px;
    color: var(--rules-text) !important;
    opacity: 1 !important;
    font-size: 1rem;
}

#rules-page .rules-lang-chip {
    flex: 0 0 auto;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 148px;
    min-height: 48px;
    padding: 10px 14px;
    border-radius: 14px;
    border: 1px solid var(--rules-border);
    background: var(--rules-soft);
    font-size: .95rem;
    font-weight: 700;
}

#rules-page .rules-meta {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
    margin-bottom: 14px;
}

#rules-page .rules-meta-card {
    border: 1px solid var(--rules-border);
    background: var(--rules-card-bg-strong);
    border-radius: 16px;
    padding: 14px 16px;
    min-width: 0;
    box-shadow: var(--rules-shadow);
}

#rules-page .rules-meta-label {
    display: block;
    margin-bottom: 6px;
    color: inherit;
    opacity: .72;
    font-size: .78rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .04em;
}

#rules-page .rules-meta-value {
    display: block;
    font-size: 1rem;
    font-weight: 700;
    word-break: break-word;
}

#rules-page .rules-note,
#rules-page .rules-note .copy {
    color: var(--rules-muted) !important;
    opacity: 1 !important;
    line-height: 1.6;
}

#rules-page .rules-note {
    padding: 6px 0 0 !important;
    font-size: .92rem !important;
}

#rules-page .rules-layout {
    display: grid;
    grid-template-columns: 260px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
}

#rules-page .rules-toc,
#rules-page .rules-section {
    border: 1px solid var(--rules-border);
    background: var(--rules-card-bg);
    border-radius: 20px;
    box-shadow: var(--rules-shadow);
    backdrop-filter: blur(12px);
}

#rules-page .rules-toc {
    position: sticky;
    top: 92px;
    padding: 16px;
}

#rules-page .rules-toc-title {
    margin: 0 0 10px;
    font-size: 1.05rem;
    font-weight: 800;
}

#rules-page .rules-toc-nav {
    display: grid;
    gap: 6px;
}

#rules-page .rules-toc-nav a {
    display: block;
    padding: 9px 10px;
    border-radius: 10px;
    font-size: .92rem;
    color: inherit;
    text-decoration: none;
    transition: background .15s ease, transform .15s ease;
}

#rules-page .rules-toc-nav a:hover {
    background: var(--rules-soft);
    transform: translateX(2px);
}

#rules-page .rules-sections {
    display: grid;
    gap: 14px;
    min-width: 0;
}

#rules-page .rules-section {
    overflow: hidden;
    scroll-margin-top: 92px;
}

#rules-page .rules-section-head {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 16px 18px;
    border-bottom: 1px solid var(--rules-border);
    background: var(--rules-card-bg-strong);
}

#rules-page .rules-section-no {
    flex: 0 0 auto;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border-radius: 999px;
    background: rgba(45, 95, 184, .12);
    color: var(--rules-accent);
    font-size: .82rem;
    font-weight: 800;
}

#rules-page .rules-section-title {
    margin: 0;
    font-size: 1.45rem;
    line-height: 1.25;
}

#rules-page .rules-section-body {
    padding: 18px;
    color: var(--rules-text);
}

#rules-page .rules-section-body p {
    margin: 0 0 12px;
}

#rules-page .rules-section-body ul {
    margin: 0;
    padding-left: 1.25em;
}

#rules-page .rules-section-body li {
    margin: 0 0 10px;
}

#rules-page .rules-subheading {
    margin: 18px 0 10px;
    font-size: 1rem;
    font-weight: 800;
}

#rules-page code {
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    font-size: .95em;
    background: var(--rules-soft-strong);
    border: 1px solid var(--rules-border);
    border-radius: 6px;
    padding: .12em .42em;
}

#rules-page .rules-desc a,
#rules-page .rules-note a,
#rules-page .rules-section-body a,
#rules-page .rules-link {
    color: var(--rules-link);
    text-decoration: underline;
    text-underline-offset: .18em;
    text-decoration-thickness: .08em;
    font-weight: 600;
}

#rules-page .rules-desc a:hover,
#rules-page .rules-note a:hover,
#rules-page .rules-section-body a:hover,
#rules-page .rules-link:hover {
    opacity: .82;
}

#rules-page .rules-desc a:visited,
#rules-page .rules-note a:visited,
#rules-page .rules-section-body a:visited,
#rules-page .rules-link:visited {
    color: var(--rules-link);
}

#rules-page .copy {
    display: none;
}

#rules-page[data-lang="ja"] .copy-ja {
    display: block;
}

#rules-page[data-lang="en"] .copy-en {
    display: block;
}

#rules-page .copy-inline {
    display: none;
}

#rules-page[data-lang="ja"] .copy-ja.copy-inline,
#rules-page[data-lang="en"] .copy-en.copy-inline {
    display: inline;
}

#rules-page .copy-inline-block {
    display: none;
}

#rules-page[data-lang="ja"] .copy-ja.copy-inline-block,
#rules-page[data-lang="en"] .copy-en.copy-inline-block {
    display: inline-block;
}

#rules-page .rules-banner {
    display: block;
    width: 100%;
    max-width: 420px;
    margin: 0 0 22px;
}

#rules-page .rules-back-to-top {
    position: fixed;
    right: 24px;
    bottom: 24px;
    z-index: 999;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    min-width: 52px;
    height: 52px;
    padding: 0 14px;
    border: 1px solid var(--rules-border);
    border-radius: 999px;
    background: var(--rules-card-bg-strong);
    color: var(--rules-text);
    box-shadow: var(--rules-shadow);
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: opacity .2s ease, transform .2s ease, visibility .2s ease, background .2s ease;
    backdrop-filter: blur(12px);
}

#rules-page .rules-back-to-top.is-visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

#rules-page .rules-back-to-top:hover {
    background: var(--rules-soft);
}

#rules-page .rules-back-to-top-text {
    font-size: .88rem;
    font-weight: 700;
    line-height: 1;
}

#rules-page .rules-back-to-top-icon {
    font-size: 1rem;
    line-height: 1;
    font-weight: 700;
}

@media (max-width:980px) {
    #rules-page .rules-meta {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    #rules-page .rules-layout {
        grid-template-columns: 1fr;
    }

    #rules-page .rules-toc {
        position: static;
        top: auto;
    }
}

@media (max-width:640px) {
    #rules-page .ndias-rules-wrap {
        padding-top: 18px;
    }

    #rules-page .ndias-wordmark {
        left: 14px;
        top: 6px;
        font-size: clamp(2.8rem, 18vw, 5rem);
    }

    #rules-page .rules-hero-card {
        padding: 18px;
        border-radius: 20px;
    }

    #rules-page .rules-hero-top {
        flex-direction: column;
        align-items: flex-start;
    }

    #rules-page .rules-meta {
        grid-template-columns: 1fr;
    }

    #rules-page .rules-section-head {
        padding: 14px 16px;
    }

    #rules-page .rules-section-body {
        padding: 16px;
    }

    #rules-page .rules-section-title {
        font-size: 1.25rem;
    }

    #rules-page .rules-back-to-top {
        right: 16px;
        bottom: 16px;
        min-width: 48px;
        height: 48px;
        padding: 0 12px;
    }

    #rules-page .rules-back-to-top-text {
        display: none;
    }
}

@media print {
    #rules-page .rules-layout {
        grid-template-columns: 1fr;
    }

    #rules-page .rules-toc {
        display: none !important;
    }
}