/* Shared site header: one structure and treatment across every portfolio page. */
.site-header {
    width: min(1320px, calc(100% - 64px));
    height: 82px;
    margin-inline: auto;
    display: flex;
    align-items: center;
    justify-content: flex-start;
    border-bottom: 1px solid #d8d7cc;
    color: #18231f;
    font-family: "Manrope", "PingFang SC", "Microsoft YaHei", sans-serif;
}

.wordmark {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 11px;
    font-weight: 800;
    letter-spacing: .12em;
}

.wordmark-mark {
    display: grid;
    place-items: center;
    width: 36px;
    height: 36px;
    flex: 0 0 auto;
    border-radius: 50%;
    background: #18231f;
    color: #f4f1e9;
    font: 18px Georgia, "Songti SC", serif;
    letter-spacing: 0;
}

.wordmark-sub {
    display: block;
    margin-top: 4px;
    color: #65716b;
    font: 9px "DM Mono", "SFMono-Regular", Consolas, monospace;
    letter-spacing: .08em;
}

.main-nav {
    display: flex;
    align-items: center;
    margin-left: auto;
    gap: clamp(18px, 3vw, 42px);
    font-size: 12px;
    font-weight: 600;
}

.main-nav a { color: inherit; text-decoration: none; transition: color .2s ease; }
.main-nav > a { display: inline-flex; align-items: center; gap: 7px; white-space: nowrap; }
.nav-icon { width: 14px; height: 14px; flex: 0 0 auto; stroke: currentColor; stroke-width: 1.7; fill: none; stroke-linecap: round; stroke-linejoin: round; }
.nav-contact .nav-icon { color: #d45b35; }
.main-nav a:hover { color: #d45b35; }
.main-nav .nav-contact { padding: 11px 15px; border: 1px solid currentColor; border-radius: 2px; }
.icon-inline { display: inline-block; width: 1em; height: 1em; vertical-align: -.16em; stroke: currentColor; stroke-width: 1.8; fill: none; stroke-linecap: round; stroke-linejoin: round; }
.main-content { padding-top: 0 !important; }

.back-to-top {
    position: fixed;
    right: 36px;
    bottom: 32px;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 52px;
    height: 52px;
    padding: 0;
    border: 1px solid rgba(255, 255, 255, .35);
    border-radius: 50%;
    background: #d45b35;
    color: #fff;
    box-shadow: 0 8px 24px rgba(24, 35, 31, .16);
    cursor: pointer;
    opacity: 0;
    pointer-events: none;
    transform: translateY(8px);
    transition: opacity .2s ease, transform .2s ease, background .2s ease;
}
.back-to-top.is-visible { opacity: 1; pointer-events: auto; transform: translateY(0); }
.back-to-top:hover { background: #b94727; }
.back-to-top:focus-visible { outline: 2px solid #18231f; outline-offset: 3px; }
.back-to-top svg { position: absolute; top: 50%; left: 50%; display: block; width: 22px; height: 22px; margin: 0; transform: translate(-50%, -50%); stroke: currentColor; stroke-width: 2; fill: none; stroke-linecap: round; stroke-linejoin: round; pointer-events: none; }

@media (max-width: 920px) {
    .site-header { width: calc(100% - 48px); }
    .main-nav { gap: 18px; }
}

@media (max-width: 680px) {
    .site-header { width: calc(100% - 40px); height: 70px; }
    .main-nav { gap: 14px; }
    .main-nav > a:not(.nav-home):not(.nav-contact) { display: none; }
    .main-nav .nav-contact { padding: 9px 11px; }
    .back-to-top { right: 20px; bottom: 20px; width: 48px; height: 48px; }
}

/* Language and mobile navigation controls. */
.site-header { position: relative; z-index: 100; }
.site-header-tools { display: flex; align-items: center; gap: 10px; margin-left: 16px; }
.language-toggle, .menu-toggle {
    min-height: 38px;
    padding: 0 12px;
    border: 1px solid rgba(24, 35, 31, .28);
    border-radius: 2px;
    background: transparent;
    color: inherit;
    font: 600 11px "DM Mono", "SFMono-Regular", Consolas, monospace;
    letter-spacing: .08em;
    cursor: pointer;
    transition: background .2s ease, color .2s ease, border-color .2s ease;
}
.language-toggle { display: inline-flex; align-items: center; justify-content: center; gap: 7px; }
.language-icon { width: 15px; height: 15px; flex: 0 0 auto; stroke: currentColor; stroke-width: 1.8; fill: none; stroke-linecap: round; stroke-linejoin: round; }
.language-toggle:hover, .menu-toggle:hover { border-color: #d45b35; color: #d45b35; }
.language-toggle:focus-visible, .menu-toggle:focus-visible { outline: 2px solid #d45b35; outline-offset: 3px; }
.menu-toggle { display: none; width: 40px; padding: 0; align-items: center; justify-content: center; }
.menu-toggle-icon, .menu-toggle-icon::before, .menu-toggle-icon::after {
    display: block; width: 16px; height: 1.5px; background: currentColor; transition: transform .2s ease;
}
.menu-toggle-icon { position: relative; }
.menu-toggle-icon::before, .menu-toggle-icon::after { position: absolute; left: 0; content: ""; }
.menu-toggle-icon::before { top: -5px; }
.menu-toggle-icon::after { top: 5px; }
.menu-toggle[aria-expanded="true"] .menu-toggle-icon { background: transparent; }
.menu-toggle[aria-expanded="true"] .menu-toggle-icon::before { top: 0; transform: rotate(45deg); }
.menu-toggle[aria-expanded="true"] .menu-toggle-icon::after { top: 0; transform: rotate(-45deg); }

@media (max-width: 920px) {
    .site-header { width: calc(100% - 40px); }
    .site-header-tools { gap: 8px; margin-left: 12px; }
    .main-nav { gap: 14px; }
}
@media (max-width: 960px) {
    .site-header { width: calc(100% - 32px); height: 68px; }
    .wordmark { gap: 9px; }
    .wordmark-mark { width: 32px; height: 32px; }
    .wordmark-sub { font-size: 8px; }
    .site-header-tools { gap: 7px; margin-left: auto; }
    .language-toggle, .menu-toggle { min-height: 38px; }
    .language-toggle { padding-inline: 10px; }
    .menu-toggle { display: inline-flex; }
    .main-nav {
        position: absolute;
        top: calc(100% + 1px);
        right: 0;
        left: 0;
        display: none;
        align-items: stretch;
        gap: 0;
        padding: 8px;
        border: 1px solid #d8d7cc;
        border-top: 0;
        background: #f4f1e9;
        box-shadow: 0 14px 28px rgba(24, 35, 31, .12);
        font-size: 14px;
    }
    .main-nav.is-open { display: flex; flex-direction: column; }
    .main-nav > a, .main-nav > a:not(.nav-home):not(.nav-contact) {
        display: flex;
        min-height: 48px;
        align-items: center;
        padding: 0 12px;
        border-bottom: 1px solid rgba(24, 35, 31, .1);
        white-space: normal;
    }
    .main-nav > a:last-child { border-bottom: 0; }
    .main-nav .nav-contact { justify-content: flex-start; margin-top: 6px; border: 1px solid currentColor; }
    .main-nav > a:hover { background: rgba(24, 35, 31, .04); }
}
@media (max-width: 380px) {
    .site-header { width: calc(100% - 24px); }
    .wordmark { font-size: 10px; }
    .wordmark-sub { letter-spacing: .04em; }
}