/* CFTS header: chrome positioning, logo/navigation controls, Sections dropdown. */
.cfts-chrome-header {
    position: sticky;
    top: 0;
    z-index: 10;
    isolation: isolate;
    border-bottom: 0;
    background: transparent;
    backdrop-filter: blur(16px);
}

.cfts-chrome-header::before {
    position: absolute;
    inset: 0 50%;
    z-index: -1;
    margin-inline: -50vw;
    border-bottom: 1px solid var(--site-line);
    background: color-mix(in srgb, var(--site-bg) 92%, transparent);
    content: "";
}

.cfts-chrome-logo-pair {
    width: 188px;
    max-width: 48vw;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: var(--site-page);
    margin: 0 auto;
    padding: 14px 0;
    background: color-mix(in srgb, var(--site-bg) 88%, transparent);
    backdrop-filter: blur(16px);
}

.site-brand {
    display: inline-flex;
    align-items: center;
    flex: 0 0 auto;
}

.site-logo {
    display: block;
    width: min(188px, 48vw);
    height: auto;
}

.site-logo-light {
    display: none;
}

@media (prefers-color-scheme: light) {
.site-logo-dark {
        display: none;
    }
.site-logo-light {
        display: block;
    }
}

:root[data-site-theme="dark"] .site-logo-dark {
    display: block;
}

:root[data-site-theme="dark"] .site-logo-light {
    display: none;
}

:root[data-site-theme="light"] .site-logo-dark {
    display: none;
}

:root[data-site-theme="light"] .site-logo-light {
    display: block;
}

.site-nav {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--site-muted);
    font-size: 0.86rem;
    font-weight: 650;
}

.site-nav a {
    min-height: 34px;
    padding: 8px 10px;
    border: 1px solid transparent;
    border-radius: 6px;
    text-decoration: none;
}

.site-nav-icon {
    width: 34px;
    min-width: 34px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 7px;
}

.site-nav-icon svg {
    width: 17px;
    height: 17px;
    fill: none;
    stroke: currentColor;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 1.9;
}

.site-theme-toggle {
    display: inline-grid;
    grid-template-columns: auto auto;
    align-items: center;
    gap: 8px;
    min-height: 34px;
    padding: 0 4px;
    color: var(--site-muted);
    font-size: 0.86rem;
    font-weight: 650;
    cursor: pointer;
    user-select: none;
}

.site-theme-toggle input {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.site-theme-toggle input:checked + .toggle-track .toggle-thumb {
    transform: translateX(18px);
}

.site-theme-toggle:has(input:focus-visible) .toggle-track {
    border-color: var(--site-accent-warm);
}

.site-nav a:hover,
.site-nav a:focus-visible,
.site-theme-toggle:hover {
    border-color: var(--site-line);
    color: var(--site-accent-warm);
    outline: 0;
}

.site-theme-toggle:hover .toggle-track {
    border-color: var(--site-accent-warm);
}

.cfts-chrome-header {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr) auto;
    align-items: center;
    column-gap: 12px;
    width: var(--site-page);
    margin: 0 auto;
    padding: 10px 0;
}

.cfts-chrome-brand {
    min-width: 0;
    justify-self: start;
}

.section-menu {
    min-width: 0;
    margin-left: 0;
    margin-right: 0;
    justify-self: start;
}

.cfts-chrome-nav {
    display: contents;
}

.cfts-chrome-nav-links {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 6px;
    min-width: 0;
    justify-self: center;
}

.cfts-chrome-controls {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 6px;
    min-width: max-content;
    justify-self: end;
}

.section-menu {
    position: relative;
    display: inline-block;
    align-self: center;
}

/* Header controls:
   The nav pills, icon buttons, and current Sections menu share these values.
   This keeps future button styling changes predictable. */
.cfts-chrome-nav-link,
.section-menu summary {
    min-height: var(--header-control-height);
    padding: var(--header-control-padding);
    border: 1px solid var(--header-control-border);
    border-radius: var(--header-control-radius);
    background: var(--header-control-bg);
    color: var(--header-control-text);
    font-size: var(--header-control-font-size);
    font-weight: var(--header-control-font-weight);
    line-height: var(--header-control-line-height);
}

.cfts-chrome-icon-button {
    width: var(--header-control-icon-width);
    height: var(--header-control-height);
    border: 1px solid var(--header-control-border);
    border-radius: var(--header-control-radius);
    background: var(--header-control-bg);
    color: var(--header-control-text);
}

.section-menu summary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: inherit;
    cursor: pointer;
    list-style: none;
    user-select: none;
}

.section-menu summary::-webkit-details-marker {
    display: none;
}

.section-menu summary::after {
    margin-left: 7px;
    color: currentColor;
    content: "▾";
    font-size: 0.68rem;
    line-height: 1;
}

.section-menu[open] summary,
.cfts-chrome-nav-link:hover,
.cfts-chrome-nav-link:focus-visible,
.cfts-chrome-nav-link.is-active,
.cfts-chrome-icon-button:hover,
.cfts-chrome-icon-button:focus-visible,
.section-menu summary:hover,
.section-menu summary:focus-visible {
    border-color: var(--header-control-hover-border);
    color: var(--header-control-hover-text);
    outline: 0;
}

.cfts-chrome-nav-link.is-active,
.section-menu[open] summary {
    background: var(--header-control-selected-bg);
    color: var(--header-control-selected-text);
}

.cfts-chrome-nav-link.is-active:hover,
.cfts-chrome-nav-link.is-active:focus-visible,
.section-menu[open] summary:hover,
.section-menu[open] summary:focus-visible {
    color: var(--header-control-hover-text);
}

.section-menu[open] summary::after {
    transform: rotate(180deg);
}

.section-menu-links {
    position: absolute;
    top: calc(100% + 6px);
    left: 0;
    z-index: 20;
    display: grid;
    gap: 2px;
    min-width: 178px;
    padding: 7px;
    border: 1px solid color-mix(in srgb, var(--site-line) 78%, transparent);
    border-radius: 8px;
    background: color-mix(in srgb, var(--site-panel) 92%, transparent);
    box-shadow: 0 14px 34px color-mix(in srgb, var(--site-shadow) 72%, transparent);
}

.section-menu-links a {
    display: block;
    padding: 6px 8px;
    border: 1px solid transparent;
    border-radius: 6px;
    color: var(--site-muted);
    font-size: 0.83rem;
    font-weight: 430;
    line-height: 1.25;
    text-decoration: none;
    white-space: nowrap;
}

.section-menu-links a:hover,
.section-menu-links a:focus-visible {
    color: var(--site-accent-warm);
    background: transparent;
    outline: 0;
}

@media (max-width: 900px) {
.site-header {
        position: static;
        display: grid;
        gap: 14px;
    }
.site-nav {
        flex-wrap: wrap;
    }
}

@media (max-width: 900px) {
.cfts-chrome-header {
        grid-template-columns: auto 1fr auto;
        row-gap: 8px;
        column-gap: 8px;
        padding: 10px 0;
    }
.section-menu {
        justify-self: start;
    }
.cfts-chrome-nav-links {
        grid-column: 1 / -1;
        grid-row: 2;
        justify-self: start;
        justify-content: flex-start;
    }
.cfts-chrome-controls {
        grid-column: 3;
        grid-row: 1;
    }
}

@media (max-width: 640px) {
.cfts-chrome-header {
        grid-template-columns: minmax(0, 1fr);
        row-gap: 9px;
    }
.cfts-chrome-brand {
        grid-column: 1;
        grid-row: 1;
        justify-self: center;
    }
.cfts-chrome-nav-links {
        grid-column: 1;
        grid-row: 2;
        width: 100%;
        justify-self: center;
        justify-content: center;
    }
.cfts-chrome-nav-link {
        width: auto;
    }
.cfts-chrome-controls {
        grid-column: 1;
        grid-row: 3;
        width: 100%;
        min-width: 0;
        justify-self: center;
        justify-content: center;
        flex-wrap: wrap;
    }
.section-menu {
        margin-left: 0;
        margin-right: 0;
    }
.section-menu-links {
        left: 0;
        right: auto;
        min-width: 188px;
    }
.site-header {
        gap: 12px;
        padding: 14px 0 10px;
    }
.site-brand {
        justify-self: center;
    }
.site-logo {
        width: min(178px, 68vw);
    }
.site-nav {
        display: grid;
        grid-template-columns: repeat(3, minmax(0, 1fr));
        gap: 6px;
        width: 100%;
    }
.site-nav a,
    .site-theme-toggle {
        min-height: 36px;
        justify-content: center;
        padding: 7px 6px;
        border: 1px solid color-mix(in srgb, var(--site-line) 72%, transparent);
        border-radius: 7px;
        background: color-mix(in srgb, var(--site-panel) 58%, transparent);
        font-size: 0.82rem;
        text-align: center;
    }
.site-nav-icon {
        width: auto;
        min-width: 0;
    }
.site-theme-toggle {
        grid-template-columns: auto auto;
    }
}

@media (max-width: 380px) {
.site-nav {
        gap: 5px;
    }
.site-nav a,
    .site-theme-toggle {
        font-size: 0.78rem;
    }
.site-theme-toggle input:checked + .toggle-track .toggle-thumb {
        transform: translateX(14px);
    }
}

@media (max-width: 420px) {
.cfts-chrome-logo-pair {
        width: 178px;
        max-width: 70vw;
    }
.cfts-chrome-controls {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@supports not (background: color-mix(in srgb, black 50%, white)) {
.site-header {
        background: var(--site-bg);
    }
}