/* ACM SAC SE Track — standalone conference one-pager.
   Light editorial design system; tokens.css + base.css are linked directly.
   All selectors page-scoped (.sac-* / body.sacse-page). */

/* ── Layout primitives ──────────────────────────────────── */
.sac-container {
    max-width: var(--container);
    margin-inline: auto;
    padding-inline: var(--container-pad);
}

/* ── Eyebrow ────────────────────────────────────────────── */
.sac-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin: 0 0 var(--sp-3);
    font-size: var(--fs-tiny);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: var(--track-caps);
    color: var(--accent-ink);
}
.sac-eyebrow::before {
    content: "";
    width: 22px;
    height: 2px;
    background: var(--accent);
}

/* ── Buttons ────────────────────────────────────────────── */
.sac-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 46px;
    padding: 10px 22px;
    font-size: var(--fs-small);
    font-weight: 700;
    letter-spacing: .02em;
    background: var(--ink);
    color: var(--paper);
    border: 1px solid var(--ink);
    transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.sac-btn:hover { background: var(--ink-soft); color: var(--paper); }
.sac-btn--outline { background: transparent; color: var(--ink); }
.sac-btn--outline:hover { background: var(--ink); color: var(--paper); }
.sac-btn--accent { background: var(--accent); border-color: var(--accent); }
.sac-btn--accent:hover { background: var(--accent-ink); border-color: var(--accent-ink); color: var(--paper); }
.sac-btn--compact {
    min-height: 36px;
    padding: 6px 14px;
    font-size: var(--fs-tiny);
    letter-spacing: .04em;
}

/* ── Masthead ───────────────────────────────────────────── */
.sac-header {
    position: fixed;
    inset: 0 0 auto 0;
    z-index: 100;
    height: var(--header-h);
    background: var(--paper);
    border-bottom: var(--rule-heavy);
    transition: box-shadow var(--dur) var(--ease);
}
.sac-header.is-scrolled { box-shadow: 0 8px 24px rgba(17, 19, 24, .07); }
.sac-header__inner {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--sp-4);
}

.sac-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    line-height: 1;
    flex-shrink: 0;
}
.sac-brand:hover { color: var(--ink); }
.sac-brand img { width: 34px; height: 34px; }
.sac-brand__name {
    font-size: 1.15rem;
    font-weight: 800;
    letter-spacing: -.02em;
    white-space: nowrap;
}

.sac-nav {
    display: flex;
    align-items: center;
    gap: clamp(12px, 1.8vw, 26px);
}
.sac-nav a {
    display: inline-block;
    padding: 6px 2px;
    font-size: var(--fs-tiny);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .08em;
    color: var(--muted);
    border-bottom: 2px solid transparent;
}
.sac-nav a:hover { color: var(--ink); border-bottom-color: var(--line-strong); }
.sac-nav a.is-active { color: var(--ink); border-bottom-color: var(--accent); }

.sac-header__actions {
    display: flex;
    align-items: center;
    gap: var(--sp-2);
    flex-shrink: 0;
}

.sac-nav-toggle {
    display: none;
    width: 44px;
    height: 44px;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--ink);
}

@media (max-width: 1023px) {
    .sac-nav {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        z-index: 95;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: var(--sp-2) var(--container-pad) var(--sp-4);
        background: var(--paper);
        border-bottom: var(--rule-heavy);
        transform: translateY(-8px);
        opacity: 0;
        visibility: hidden;
        transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease), visibility 0s linear var(--dur);
    }
    .sac-header.is-nav-open .sac-nav {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
        transition-delay: 0s;
    }
    .sac-nav a {
        display: block;
        padding: 14px 4px;
        font-size: .98rem;
        letter-spacing: .06em;
        border-bottom: var(--hair);
    }
    .sac-nav a.is-active { border-bottom-color: var(--accent); }
    .sac-nav-toggle { display: flex; }
}

@media (max-width: 479px) {
    .sac-brand__name { font-size: 1rem; }
    .sac-btn--compact span { display: none; }
    .sac-btn--compact { padding: 6px 10px; }
}

/* ── Hero ───────────────────────────────────────────────── */
.sac-hero {
    padding-block: clamp(56px, 9vw, 110px) clamp(40px, 6vw, 72px);
    border-bottom: var(--hair);
}
.sac-hero__title {
    font-size: var(--fs-display);
    font-weight: 800;
    letter-spacing: -.025em;
    max-width: 26ch;
    margin-bottom: .4em;
}
.sac-hero__meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--sp-2) var(--sp-4);
    font-size: 1.02rem;
    font-weight: 600;
    color: var(--muted);
}
.sac-hero__meta i { color: var(--accent-ink); margin-right: 4px; }
.sac-hero__actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--sp-2);
    margin-top: var(--sp-5);
}

/* ── Section rhythm + headers ───────────────────────────── */
.sac-section { padding-block: clamp(30px, 4.5vw, 52px); }
.sac-section--soft {
    background: var(--paper-soft);
    border-bottom: var(--hair);
    padding-block: clamp(44px, 6.5vw, 80px);
}

.sac-section__header {
    border-top: var(--rule-heavy);
    padding-top: var(--sp-3);
    margin-bottom: clamp(20px, 3.5vw, 36px);
}
.sac-section__header .sac-eyebrow { margin-bottom: 4px; }
.sac-section__title {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 8px 14px;
    margin: 0;
    font-size: var(--fs-h2);
}
.sac-section__title i {
    font-size: .78em;
    color: var(--accent-ink);
}

.sac-count {
    display: inline-block;
    padding: 3px 12px;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-pill);
    font-size: var(--fs-tiny);
    font-weight: 700;
    letter-spacing: .04em;
    color: var(--muted);
    white-space: nowrap;
}

/* ── Schedule (Important Dates) ─────────────────────────── */
.sac-schedule {
    list-style: none;
    margin: 0;
    padding: 0;
    border-top: var(--rule-heavy);
}
.sac-schedule__row {
    display: grid;
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: var(--sp-3) var(--sp-5);
    align-items: start;
    margin: 0;
    padding-block: var(--sp-4);
    border-bottom: var(--hair);
}
.sac-schedule__label h3 {
    margin: 0 0 8px;
    font-size: var(--fs-h3);
}

.sac-status {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 3px 10px;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-pill);
    font-size: var(--fs-tiny);
    font-weight: 700;
    letter-spacing: .04em;
    color: var(--muted);
    white-space: nowrap;
}
.sac-status--extended { border-color: var(--accent); color: var(--accent-ink); }
.sac-status--final { border-color: var(--ink); color: var(--ink); }

.sac-schedule__dates { display: flex; align-items: center; min-height: 100%; }
.sac-date-flow {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--sp-2) var(--sp-3);
}
.sac-date {
    display: flex;
    flex-direction: column;
    gap: 2px;
}
.sac-date__tag {
    font-size: var(--fs-tiny);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .08em;
    color: var(--muted);
}
.sac-date--old del { color: var(--faint); font-weight: 600; }
.sac-date--current strong {
    font-size: 1.12rem;
    font-weight: 800;
    letter-spacing: -.01em;
    color: var(--ink);
}
.sac-schedule__row--extended .sac-date--current strong { color: var(--accent-ink); }
.sac-date-flow__arrow { color: var(--faint); font-size: 1.05rem; }

.sac-schedule__history { grid-column: 1 / -1; }
.sac-schedule__history-title {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: var(--fs-tiny);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .08em;
    color: var(--muted);
}
.sac-history {
    list-style: none;
    margin: 8px 0 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: 6px;
}
.sac-history__item {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 4px 12px;
    margin: 0;
    font-size: var(--fs-small);
}
.sac-history__badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 1px 9px;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-pill);
    font-size: var(--fs-tiny);
    font-weight: 700;
    color: var(--muted);
    white-space: nowrap;
}
.sac-history__item--final .sac-history__badge { border-color: var(--ink); color: var(--ink); }
.sac-history__item--extension .sac-history__badge { border-color: var(--accent); color: var(--accent-ink); }
.sac-history__date { font-weight: 600; }
.sac-history__notice { color: var(--muted); }

.sac-schedule__notice {
    grid-column: 1 / -1;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin: 0;
    padding: 12px 14px;
    background: var(--paper);
    border: 1px solid var(--line-strong);
    border-left: 3px solid var(--accent);
    font-size: var(--fs-small);
}
.sac-schedule__notice i { color: var(--accent-ink); line-height: 1.6; }
.sac-schedule__notice--final { border-left-color: var(--ink); }
.sac-schedule__notice--final i { color: var(--ink); }

@media (max-width: 767px) {
    .sac-schedule__row { grid-template-columns: 1fr; gap: var(--sp-2); }
}

/* ── Prose (DB HTML content) ────────────────────────────── */
.sac-prose { max-width: 72ch; }
.sac-prose a,
.sac-card a,
.sac-alert__content a,
.sac-inquiry a {
    font-weight: 600;
    text-decoration: underline;
    text-underline-offset: 3px;
    text-decoration-color: var(--line-strong);
}
.sac-prose a:hover,
.sac-card a:hover,
.sac-alert__content a:hover,
.sac-inquiry a:hover {
    color: var(--accent-ink);
    text-decoration-color: var(--accent);
}

/* ── Topics ─────────────────────────────────────────────── */
.sac-subheading {
    margin: var(--sp-5) 0 var(--sp-3);
    font-size: var(--fs-small);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .08em;
    color: var(--ink-soft);
}
.sac-topics {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: var(--sp-2);
}
.sac-topics li.sac-topic {
    display: inline-flex;
    align-items: center;
    margin: 0;
    padding: 7px 16px;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius-pill);
    font-size: var(--fs-small);
    font-weight: 600;
    color: var(--ink-soft);
}

/* ── Alert sections (bordered notes) ────────────────────── */
.sac-alert {
    display: flex;
    gap: var(--sp-3);
    max-width: 860px;
    padding: var(--sp-4);
    border: 1px solid var(--line-strong);
    border-left: 3px solid var(--accent);
    background: var(--paper);
}
.sac-alert__icon {
    flex: 0 0 auto;
    font-size: 1.3rem;
    line-height: 1.4;
    color: var(--accent-ink);
}
.sac-alert__title {
    margin: 0 0 6px;
    font-size: var(--fs-h3);
    font-weight: 800;
}
.sac-alert__content {
    font-size: var(--fs-small);
    overflow-wrap: anywhere;
}
.sac-alert__content ul { padding-left: 18px; margin: 8px 0; }

/* ── Content cards (submission / accepted / src) ────────── */
.sac-card {
    max-width: 860px;
    padding: var(--sp-4);
    border: var(--hair);
    background: var(--paper);
}
.sac-card--compact {
    padding: var(--sp-3) var(--sp-4);
    font-size: var(--fs-small);
}
.sac-card p { margin-bottom: 10px; }
.sac-card p:last-child { margin-bottom: 0; }
.sac-card strong { font-weight: 700; }
.sac-card ul { padding-left: 18px; margin: 10px 0; }
.sac-card ul li { margin-bottom: 5px; }
.sac-card ul:last-child { margin-bottom: 0; }

/* ── Chairs ─────────────────────────────────────────────── */
.sac-chairs {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: var(--sp-4) var(--sp-5);
}
.sac-chair {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 3px;
    padding-top: var(--sp-3);
    border-top: var(--rule-heavy);
}
.sac-chair--lead { border-top-color: var(--accent); }
.sac-chair__role {
    margin-bottom: 6px;
    padding: 2px 10px;
    border: 1px solid var(--accent);
    border-radius: var(--radius-pill);
    font-size: var(--fs-tiny);
    font-weight: 700;
    letter-spacing: .04em;
    color: var(--accent-ink);
}
.sac-chair__name { margin: 0; font-size: var(--fs-h3); }
.sac-chair__aff { margin: 0; color: var(--muted); font-size: var(--fs-small); }
.sac-chair__email {
    margin-top: 6px;
    font-size: var(--fs-small);
    font-weight: 600;
    color: var(--ink);
    overflow-wrap: anywhere;
}
.sac-chair__email i { color: var(--accent-ink); margin-right: 4px; }
.sac-chair__email:hover { color: var(--accent-ink); }

@media (max-width: 1023px) {
    .sac-chairs { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 639px) {
    .sac-chairs { grid-template-columns: 1fr; }
}

/* ── Program Committee ──────────────────────────────────── */
.sac-pc {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 var(--sp-5);
    border-top: var(--rule-heavy);
}
.sac-pc__item {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin: 0;
    padding-block: 12px;
    border-bottom: var(--hair);
}
.sac-pc__item strong { font-weight: 700; }
.sac-pc__item span { color: var(--muted); font-size: var(--fs-small); }

@media (max-width: 1023px) {
    .sac-pc { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 639px) {
    .sac-pc { grid-template-columns: 1fr; }
}

/* ── Inquiry ────────────────────────────────────────────── */
.sac-inquiry {
    display: flex;
    gap: var(--sp-3);
    max-width: 860px;
    padding: var(--sp-4);
    border: 1px solid var(--ink);
    background: var(--paper);
}
.sac-inquiry > i {
    flex: 0 0 auto;
    font-size: 1.2rem;
    line-height: 1.5;
    color: var(--accent-ink);
}
.sac-inquiry__body { min-width: 0; overflow-wrap: anywhere; }

/* ── Footer ─────────────────────────────────────────────── */
.sac-footer {
    margin-top: clamp(40px, 7vw, 80px);
    padding-block: var(--sp-4);
    border-top: var(--rule-heavy);
    font-size: var(--fs-small);
    color: var(--muted);
}
.sac-footer p { margin: 0; }
.sac-footer a { font-weight: 700; color: var(--ink); }
.sac-footer a:hover { color: var(--accent-ink); }

/* ── Scroll top ─────────────────────────────────────────── */
.sac-scroll-top {
    position: fixed;
    right: var(--sp-3);
    bottom: var(--sp-3);
    z-index: 80;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--paper);
    border: 1px solid var(--ink);
    color: var(--ink);
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px);
    transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease), visibility 0s linear var(--dur);
}
.sac-scroll-top.is-visible {
    opacity: 1;
    visibility: visible;
    transform: none;
    transition-delay: 0s;
}
.sac-scroll-top:hover { background: var(--ink); color: var(--paper); }