/* ===================================================================
   ESA LINE SYSTEM — styles
   Spec: ESA-LINE-SYSTEM-SPEC.md. Load after the page's own stylesheets.
   =================================================================== */

:root {
    --L: clamp(28px, 5.667vw, 96px);           /* one lattice step = one esa circle radius */
    --L4: calc(var(--L) / 4);                  /* fine lattice */
    --logo-h: clamp(15px, 3.1vw, 30px);
    --ls-ink: var(--color-primary, #1a1a1a);
}

/* ---------- nav: the logo's bar is the nav rule, links stand on it ---------- */
html.ls-on .navbar {
    box-shadow: none !important;               /* main.js adds a scroll shadow; the bar is the edge now */
    border-bottom: none;
    padding-block: var(--L4);
    padding-inline: 0;
    background-color: var(--color-bg);
    backdrop-filter: none;
}
html.ls-on .nav-container {
    position: relative;
    max-width: none;
    margin: 0;
    height: var(--logo-h);
    padding: 0;
    display: block;
}
.ls-nav-svg {
    position: absolute;
    left: var(--L);
    top: 0;
    width: calc(100% - 2 * var(--L));
    height: 100%;
    overflow: visible;
    color: var(--ls-ink);
    pointer-events: none;
}
html.ls-on .navbar .logo {
    position: absolute;
    left: var(--L);
    top: 0;
    height: 100%;
    width: calc(var(--logo-h) * 2.579);       /* the word's own width, so only the mark is the link */
    font-size: 0;
    color: transparent;
    z-index: 1;
}
html.ls-on .navbar .logo:focus-visible {
    outline: 2px solid var(--ls-ink);
    outline-offset: 4px;
}
.ls-nav-right {
    position: absolute;
    right: var(--L);
    bottom: calc(50% + clamp(3px, 0.5vw, 6px));
    display: flex;
    align-items: flex-end;
    gap: clamp(0.9rem, 2vw, 2rem);
    line-height: 1;
    opacity: 0;
    transition: opacity 0.6s ease;
}
.ls-links-in .ls-nav-right { opacity: 1; }
html.ls-on .nav-menu { gap: clamp(0.9rem, 2vw, 2rem); align-items: flex-end; }
html.ls-on .nav-link { line-height: 1; display: block; }
html.ls-on .nav-link::after { display: none; }
html.ls-on .navbar .theme-toggle {
    border: none;
    padding: 0;
    margin: 0;
    line-height: 1;
    font-size: var(--text-sm);
    color: var(--color-text-light);
    background: transparent;
}
html.ls-on .navbar .theme-toggle:hover { color: var(--color-primary); }
html.ls-on .theme-icon:empty { display: none; }

@media (max-width: 768px) {
    html.ls-on .nav-menu {
        top: calc(var(--logo-h) + 2 * var(--L4));
        align-items: center;
        background-color: var(--color-bg);
    }
    html.ls-on .nav-menu .nav-link { line-height: 1.5; }
    html.ls-on .hamburger { padding-bottom: 1px; }
}

/* ---------- outlines ---------- */
.ls-outline-layer {
    position: absolute;
    left: 0;
    top: 0;
    pointer-events: none;
    overflow: visible;
    color: var(--ls-ink);
    z-index: 900;                              /* over content, under the fixed nav */
}

/* components the outline replaces: no CSS borders, lattice corners */
html.ls-on .project-image-container,
html.ls-on .project-card .project-image,
html.ls-on .nav-btn {
    border: none;
    border-radius: var(--L);
    overflow: hidden;
}
html.ls-on .project-hero-image {
    border-radius: var(--L);
    overflow: hidden;
    margin-inline: var(--L);
    width: round(down, calc(100% - 2 * var(--L)), var(--L));
}
html.ls-on .gallery-item img {
    border-radius: var(--L);
    border: none;
}
html.ls-on .download-btn,
html.ls-on .btn,
html.ls-on .filter-btn,
html.ls-on .arrow-button {
    border-color: transparent;
    border-radius: 999px;
    min-height: calc(2 * var(--L4));
}
html.ls-on .project-navigation { border-top: none; }
html.ls-on .project-header { border-bottom: none; }
html.ls-on .contact-form input,
html.ls-on .contact-form textarea {
    border-color: transparent;
    border-radius: var(--L4);
}

/* ---------- landing ---------- */
.ls-word {
    position: fixed;
    inset: 0;
    z-index: 1100;
    color: var(--ls-ink);
    background: var(--color-bg);
    cursor: pointer;
    transition: background-color 0.9s ease;
}
.ls-word svg { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
.ls-word.is-leaving { background-color: transparent; pointer-events: none; }
.ls-word-prompt {
    position: absolute;
    left: 0;
    right: 0;
    bottom: calc(2 * var(--L4));
    text-align: center;
    font-size: var(--text-xs);
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-text-light);
    opacity: 0;
    transition: opacity 0.6s ease;
    pointer-events: none;
}
.ls-word.is-ready .ls-word-prompt { opacity: 1; }
.ls-word.is-leaving .ls-word-prompt { opacity: 0; }

/* home: every edge on the lattice */
.ls-home {
    padding-top: calc(var(--logo-h) + 2 * var(--L4) + var(--L));
    padding-inline: var(--L);
    padding-bottom: var(--L);
    display: grid;
    grid-template-columns: repeat(auto-fill, var(--L));
    grid-auto-rows: var(--L);
    align-content: start;
    transition: opacity 0.8s ease;
}
.ls-home.is-waiting { opacity: 0; }
.ls-home > * { min-width: 0; min-height: 0; margin: 0; }

.ls-hero {
    grid-column: 1 / span 8;
    grid-row: 1 / span 5;
    border-radius: var(--L);
    overflow: hidden;
    display: block;
    position: relative;
}
.ls-hero img, .ls-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: grayscale(100%);
    transition: filter var(--transition-slow, 0.6s);
}
.ls-hero:hover img, .ls-thumb:hover img { filter: grayscale(0); }
.ls-hero-caption, .ls-thumb-caption {
    position: absolute;
    left: var(--L4);
    bottom: var(--L4);
    font-size: var(--text-xs);
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--color-primary);
    background: var(--color-bg);
    padding: 0.35em 0.9em;
    border-radius: 999px;
}

.ls-intro {
    grid-column: 10 / span 6;
    grid-row: 1 / span 5;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}
.ls-intro h1 {
    font-size: var(--text-2xl);
    font-weight: 500;
    line-height: 1.05;
    letter-spacing: -0.02em;
    text-wrap: balance;
    padding-top: var(--L4);
}
.ls-intro p {
    font-size: var(--text-base);
    line-height: 1.55;
    color: var(--color-text-light);
    max-width: 40ch;
}
.ls-intro .ls-rule-row { height: var(--L); display: flex; align-items: center; }

.ls-thumb {
    grid-row: 7 / span 3;
    border-radius: var(--L);
    overflow: hidden;
    position: relative;
    display: block;
}
.ls-thumb-1 { grid-column: 1 / span 3; }
.ls-thumb-2 { grid-column: 6 / span 3; }

.ls-cta-row {
    grid-column: 10 / span 6;
    grid-row: 7 / span 3;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    gap: var(--L4);
}
.ls-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: max(calc(3 * var(--L4)), 44px);     /* touch target floor on phones */
    padding-inline: var(--L);
    border-radius: 999px;
    font-size: var(--text-sm);
    letter-spacing: 0.04em;
    color: var(--color-primary);
    align-self: flex-start;
}
.ls-cta-secondary { color: var(--color-text-light); }

@media (max-width: 900px) {
    /* narrow: stack, but every height stays a whole number of lattice steps */
    .ls-home { display: flex; flex-wrap: wrap; gap: var(--L) var(--L); align-content: flex-start; }
    .ls-hero   { width: 100%; height: calc(7 * var(--L)); }
    .ls-intro  { width: 100%; gap: var(--L4); }
    .ls-thumb  { width: calc(50% - var(--L) / 2); height: calc(5 * var(--L)); }
    .ls-cta-row { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
    .ls-word, .ls-home, .ls-nav-right { transition: none; }
}