/* ------------------------------------------------------------------ *\
   Amgalan-Ochir Chuluunbaatar — portfolio
   Editorial "technical dossier" system: paper + ink, one accent,
   hairline rules, mono metadata. No gradients, no glass, no mockups.
\* ------------------------------------------------------------------ */

:root {
    --bg: #f3efe6;
    --bg-2: #ece7da;
    --surface: #faf7f0;
    --ink: #1a1812;
    --muted: #6c675c;
    --faint: #908a7c;
    --line: #d6cfbd;
    --line-strong: #b7af9b;
    --accent: #cc4222;
    --accent-ink: #ffffff;
    --ok: #3f7d4f;

    --font-display: "Space Grotesk", "Segoe UI", system-ui, sans-serif;
    --font-mono: "JetBrains Mono", ui-monospace, "Cascadia Code", Consolas, monospace;
    --radius: 4px;
}

[data-theme="dark"] {
    --bg: #100f0c;
    --bg-2: #161510;
    --surface: #1a1813;
    --ink: #ece7da;
    --muted: #948e80;
    --faint: #6f6a5d;
    --line: #2c2a22;
    --line-strong: #45412f;
    --accent: #ff6a45;
    --accent-ink: #140d09;
    --ok: #6bbf7f;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    overflow-x: hidden;
    background: var(--bg);
    color: var(--ink);
    font-family: var(--font-display);
    font-size: 17px;
    line-height: 1.55;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

::selection {
    background: var(--accent);
    color: var(--accent-ink);
}

img, iframe { max-width: 100%; }

a { color: inherit; }

a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 3px;
}

.container {
    width: min(1180px, calc(100% - 48px));
    margin: 0 auto;
}

/* ---- Header ------------------------------------------------------- */

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
}

.nav-wrap {
    display: flex;
    min-height: 70px;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.brand {
    display: flex;
    min-width: 0;
    align-items: center;
    gap: 13px;
    text-decoration: none;
}

.brand-mark {
    display: inline-flex;
    width: 40px;
    height: 40px;
    flex: 0 0 auto;
    align-items: center;
    justify-content: center;
    border-radius: 3px;
    background: var(--ink);
    color: var(--bg);
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 15px;
    letter-spacing: -0.02em;
}

.brand strong,
.brand small { display: block; }

.brand strong {
    font-size: 15px;
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.01em;
    max-width: 30ch;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.brand small {
    color: var(--faint);
    font-family: var(--font-mono);
    font-size: 10.5px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2px;
}

.nav-links a,
.theme-toggle {
    min-height: 40px;
    display: inline-flex;
    align-items: center;
    border: 0;
    border-radius: 3px;
    background: transparent;
    color: var(--muted);
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    text-decoration: none;
    padding: 8px 12px;
}

.nav-links a:hover,
.theme-toggle:hover { color: var(--ink); }

.nav-links a.active {
    color: var(--ink);
    box-shadow: inset 0 -2px 0 var(--accent);
    border-radius: 0;
}

.theme-toggle { margin-left: 8px; }

.menu-btn {
    display: none;
    width: 42px;
    height: 42px;
    border: 1px solid var(--line);
    border-radius: 3px;
    background: var(--surface);
    cursor: pointer;
    padding: 11px;
}

.menu-btn span {
    display: block;
    height: 1.5px;
    margin: 5px 0;
    background: var(--ink);
}

/* ---- Sections ----------------------------------------------------- */

.section { padding: clamp(60px, 9vw, 104px) 0; }

main > section + section { border-top: 1px solid var(--line); }

.muted { background: var(--bg-2); }

/* Index numbering — homepage only */
.home { counter-reset: sec; }

.eyebrow {
    display: flex;
    align-items: baseline;
    gap: 12px;
    margin: 0 0 18px;
    color: var(--accent);
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    letter-spacing: 0.18em;
    text-transform: uppercase;
}

.home .eyebrow { counter-increment: sec; }

.home .eyebrow::before {
    content: counter(sec, decimal-leading-zero);
    color: var(--faint);
    letter-spacing: 0.1em;
    padding-right: 12px;
    border-right: 1px solid var(--line-strong);
}

/* ---- Typography --------------------------------------------------- */

h1, h2, h3 {
    color: var(--ink);
    font-family: var(--font-display);
    font-weight: 600;
}

.hero h1, main h1 {
    margin: 0 0 18px;
    font-size: clamp(42px, 7.5vw, 88px);
    font-weight: 700;
    line-height: 0.98;
    letter-spacing: -0.035em;
}

main h2 {
    margin: 0 0 14px;
    font-size: clamp(26px, 3.4vw, 40px);
    line-height: 1.08;
    letter-spacing: -0.022em;
}

.hero h2 {
    margin: 0 0 22px;
    color: var(--muted);
    font-weight: 500;
    font-size: clamp(19px, 2.4vw, 26px);
    letter-spacing: -0.01em;
}

h3 {
    margin: 0 0 8px;
    font-size: 18px;
    letter-spacing: -0.01em;
}

p { color: var(--muted); margin: 0 0 14px; }

.lead {
    max-width: 62ch;
    color: var(--ink);
    font-size: clamp(18px, 1.8vw, 21px);
    line-height: 1.5;
}

.narrow { max-width: 64ch; }

/* ---- Buttons & links --------------------------------------------- */

.button-row {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 30px;
}

.btn {
    display: inline-flex;
    min-height: 46px;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--ink);
    border-radius: var(--radius);
    font-family: var(--font-mono);
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.04em;
    padding: 12px 22px;
    text-decoration: none;
    transition: background-color .15s, color .15s, border-color .15s, transform .15s;
}

.btn.primary {
    background: var(--ink);
    color: var(--bg);
}

.btn.primary:hover {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--accent-ink);
}

.btn.secondary {
    background: transparent;
    border-color: var(--line-strong);
    color: var(--ink);
}

.btn.secondary:hover { border-color: var(--ink); }

.text-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--accent);
    font-family: var(--font-mono);
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.03em;
    text-decoration: none;
}

.text-link::after { content: "\2192"; transition: transform .15s; }
.text-link:hover::after { transform: translateX(4px); }

/* ---- Hero --------------------------------------------------------- */

.hero {
    border-bottom: 0;
    padding-top: clamp(56px, 8vw, 96px);
    padding-bottom: clamp(56px, 8vw, 96px);
}

.hero-grid,
.two-col {
    display: grid;
    grid-template-columns: minmax(0, 1.25fr) minmax(300px, 0.85fr);
    gap: clamp(32px, 5vw, 72px);
    align-items: start;
}

.two-col { align-items: start; }

/* Identity card — replaces the fake terminal */
.hero-card {
    border: 1px solid var(--line-strong);
    border-radius: var(--radius);
    background: var(--surface);
    overflow: hidden;
}

.hero-card-head {
    display: flex;
    align-items: center;
    gap: 9px;
    padding: 13px 18px;
    border-bottom: 1px solid var(--line);
    background: var(--bg-2);
    color: var(--muted);
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.16em;
    text-transform: uppercase;
}

.hero-card-head small { margin-left: auto; color: var(--ok); }

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 999px;
    background: var(--ok);
}

.hero-card-row {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: 16px;
    padding: 14px 18px;
    border-bottom: 1px solid var(--line);
    font-family: var(--font-mono);
    font-size: 13px;
}

.hero-card-row:last-child { border-bottom: 0; }

.hero-card-row .k {
    color: var(--faint);
    font-size: 11px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
}

.hero-card-row .v { color: var(--ink); text-align: right; }
.hero-card-row .v.accent { color: var(--accent); }

/* ---- Cards & grids ----------------------------------------------- */

.card {
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--surface);
    padding: 24px;
}

.large-text {
    font-size: clamp(17px, 1.5vw, 19px);
    line-height: 1.6;
    color: var(--ink);
}

.card-grid {
    display: grid;
    gap: 0;
    margin-top: 36px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    overflow: hidden;
}

.card-grid.five { grid-template-columns: repeat(5, minmax(0, 1fr)); }

/* Connected (Swiss) grid: shared hairlines instead of floating cards */
.card-grid .card {
    border: 0;
    border-radius: 0;
    border-right: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    background: transparent;
    transition: background-color .15s;
}

.card-grid .card:hover { background: var(--surface); }

.card-grid .card h3 {
    padding-top: 14px;
    border-top: 2px solid var(--accent);
    display: inline-block;
}

.skills-list {
    display: grid;
    gap: 14px;
    margin-top: 26px;
}

.tags,
.badge-row,
.tool-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tags span,
.badge-row span,
.tool-grid span {
    border: 1px solid var(--line-strong);
    border-radius: 3px;
    background: transparent;
    color: var(--muted);
    font-family: var(--font-mono);
    font-size: 12.5px;
    padding: 6px 10px;
}

.tool-grid { margin-top: 24px; }
.tool-grid span { min-width: 96px; }

.badge {
    display: inline-flex;
    align-self: flex-start;
    border: 1px solid var(--accent);
    border-radius: 3px;
    color: var(--accent);
    font-family: var(--font-mono);
    font-size: 11px;
    font-weight: 500;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    padding: 5px 9px;
    margin: 0 0 16px;
}

/* ---- Featured project -------------------------------------------- */

.project-feature {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    gap: 0;
    margin-top: 32px;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius);
    background: var(--surface);
    overflow: hidden;
}

.project-feature > div:last-child { padding: clamp(24px, 3vw, 40px); }

.project-visual {
    min-height: 320px;
    background: var(--ink);
    border-right: 1px solid var(--line-strong);
}

.project-visual img,
.image-card img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* ---- Project grid ------------------------------------------------- */

.project-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    margin-top: 38px;
}

.project-card {
    display: flex;
    flex-direction: column;
    gap: 12px;
    transition: border-color .15s, transform .15s;
}

.project-card:hover {
    border-color: var(--line-strong);
    transform: translateY(-3px);
}

.project-card h2 { font-size: 21px; line-height: 1.15; }
.project-card .text-link { margin-top: auto; }

/* ---- Timeline ----------------------------------------------------- */

.timeline { display: grid; gap: 16px; }
.timeline.full { margin-top: 38px; }

.timeline-item { position: relative; }
.timeline-item h2 { font-size: 22px; }

.timeline-item strong {
    display: block;
    margin-bottom: 12px;
    color: var(--accent);
    font-family: var(--font-mono);
    font-size: 13px;
    letter-spacing: 0.02em;
}

.timeline-item ul,
.split-section ul {
    margin: 14px 0 0;
    padding-left: 18px;
    color: var(--muted);
}

.timeline-item li,
.split-section li { margin-bottom: 6px; }

.badge-row { margin-top: 28px; }

/* ---- CTA ---------------------------------------------------------- */

.cta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 32px;
    border: 1px solid var(--line-strong);
    border-radius: var(--radius);
    padding: clamp(28px, 4vw, 48px);
    background: var(--surface);
}

.cta h2 { margin-bottom: 8px; }
.cta p { margin: 0; max-width: 52ch; }

/* ---- Split / detail sections ------------------------------------- */

.split-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 28px;
    margin-top: 48px;
}

.split-section h2 { font-size: 24px; margin-top: 8px; }
.split-section .card { margin-bottom: 16px; }

.feature-list { display: grid; gap: 12px; }

.feature-list .card {
    color: var(--ink);
    padding: 16px 20px;
    border-left: 2px solid var(--accent);
}

.pdf-card iframe {
    width: 100%;
    min-height: 440px;
    border: 0;
    border-radius: var(--radius);
    background: var(--bg-2);
}

.screenshot-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-top: 28px;
}

.image-card { padding: 0; overflow: hidden; }
.image-card img { aspect-ratio: 16 / 10; }

.video-placeholder { margin-top: 18px; }

.video-placeholder code {
    display: block;
    margin-top: 8px;
    overflow-wrap: anywhere;
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--accent);
}

/* ---- Contact ------------------------------------------------------ */

.contact-list { display: grid; gap: 0; margin-top: 28px; }

.contact-list.card { padding: 0; }

.contact-list p {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    margin: 0;
    padding: 14px 20px;
    border-bottom: 1px solid var(--line);
    font-family: var(--font-mono);
    font-size: 13px;
}

.contact-list p:last-child { border-bottom: 0; }
.contact-list strong { color: var(--faint); font-weight: 500; }

.contact-form { display: grid; gap: 14px; }

.contact-form label {
    color: var(--ink);
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: -6px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    min-height: 46px;
    border: 1px solid var(--line-strong);
    border-radius: 3px;
    background: var(--bg);
    color: var(--ink);
    font-family: var(--font-display);
    font-size: 16px;
    padding: 12px 14px;
    transition: border-color .15s;
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--accent);
    outline: none;
}

.contact-form textarea { resize: vertical; }

.form-success,
.form-error {
    border-radius: 3px;
    font-family: var(--font-mono);
    font-size: 13px;
    margin: 0;
    padding: 12px 14px;
}

.form-success {
    border: 1px solid var(--ok);
    color: var(--ok);
}

.form-error {
    border: 1px solid var(--accent);
    color: var(--accent);
}

.form-error p { color: inherit; margin: 0; }

/* ---- Footer ------------------------------------------------------- */

.site-footer {
    border-top: 1px solid var(--line);
    background: var(--bg);
    padding: 40px 0;
}

.footer-grid {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.footer-grid strong { font-size: 15px; letter-spacing: -0.01em; }

.footer-grid p {
    margin: 6px 0 0;
    color: var(--faint);
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.04em;
}

.footer-links { display: flex; flex-wrap: wrap; gap: 4px; }

.footer-links a {
    min-height: 40px;
    display: inline-flex;
    align-items: center;
    color: var(--muted);
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    text-decoration: none;
    padding: 6px 10px;
}

.footer-links a:hover { color: var(--ink); }

/* ---- Responsive --------------------------------------------------- */

@media (max-width: 980px) {
    .hero-grid,
    .two-col,
    .project-feature,
    .split-section { grid-template-columns: 1fr; }

    .card-grid.five { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .project-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .project-visual { min-height: 240px; border-right: 0; border-bottom: 1px solid var(--line-strong); }
}

@media (max-width: 720px) {
    .container { width: min(100% - 32px, 1180px); }

    .menu-btn { display: block; }

    .nav-links {
        position: fixed;
        left: 16px;
        right: 16px;
        top: 76px;
        display: none;
        flex-direction: column;
        align-items: stretch;
        border: 1px solid var(--line-strong);
        border-radius: var(--radius);
        background: var(--surface);
        padding: 10px;
    }

    .nav-links.open { display: flex; }
    .nav-links a, .theme-toggle { text-align: left; justify-content: flex-start; }

    .card-grid.five,
    .project-grid,
    .screenshot-grid { grid-template-columns: 1fr; }

    .card-grid .card { border-right: 0; }

    .cta, .footer-grid { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 420px) {
    .brand small { display: none; }
    .button-row, .btn { width: 100%; }
}