/* =============================================
   Yi Ding — Personal Site
   A warm-gray, architectural minimal aesthetic.
   ============================================= */

@import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond:ital,wght@0,300;0,400;0,500;1,300;1,400&family=Inter:wght@300;400;500;600&family=JetBrains+Mono:wght@400&display=swap');

:root {
  /* Palette — warm cream / stone */
  --bg:           #F2ECE0;
  --bg-2:         #E8E0CF;
  --bg-3:         #D8CDB6;
  --ink:          #1F1B15;
  --ink-2:        #4A4137;
  --ink-3:        #7A6F5F;
  --line:         #C7BCA6;
  --line-soft:    #DFD5BF;
  --accent:       #6B5D4B;

  /* Type */
  --serif: 'Cormorant Garamond', 'Times New Roman', serif;
  --sans:  'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono:  'JetBrains Mono', ui-monospace, monospace;

  /* Spacing scale */
  --gutter: clamp(1.25rem, 4vw, 4rem);
  --section: clamp(4rem, 10vw, 8rem);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-weight: 300;
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  letter-spacing: 0.01em;
}

img, svg { display: block; max-width: 100%; }

a { color: inherit; text-decoration: none; }

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

/* =============================================
   NAV
   ============================================= */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem var(--gutter);
  background: rgba(242, 236, 224, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line-soft);
}

.nav__brand {
  font-family: var(--serif);
  font-size: 1.25rem;
  font-weight: 400;
  letter-spacing: 0.02em;
}

.nav__brand em {
  font-style: italic;
  color: var(--ink-3);
}

.nav__links {
  display: flex;
  gap: clamp(1.25rem, 3vw, 2.5rem);
  list-style: none;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-weight: 400;
}

.nav__links a {
  position: relative;
  color: var(--ink-2);
  transition: color 0.3s ease;
}

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

.nav__links a.is-active {
  color: var(--ink);
}

.nav__links a.is-active::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -6px;
  height: 1px;
  background: var(--ink);
}

/* =============================================
   LAYOUT BLOCKS
   ============================================= */
main { padding-top: 80px; }

.page {
  max-width: 1280px;
  margin: 0 auto;
  padding: var(--section) var(--gutter);
}

.page--narrow { max-width: 880px; }

.page__eyebrow {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1.25rem;
}

.page__title {
  font-family: var(--serif);
  font-weight: 300;
  font-size: clamp(2.5rem, 7vw, 5.5rem);
  line-height: 1.02;
  letter-spacing: -0.015em;
  margin-bottom: 1.5rem;
}

.page__title em { font-style: italic; color: var(--ink-3); }

.page__lede {
  font-family: var(--serif);
  font-style: italic;
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  font-weight: 300;
  color: var(--ink-2);
  max-width: 56ch;
  line-height: 1.5;
  margin-bottom: 4rem;
}

.divider {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 4rem 0;
}

.divider--soft { border-top-color: var(--line-soft); }

/* =============================================
   HOME / HERO
   ============================================= */
.hero {
  min-height: calc(100vh - 80px);
  display: grid;
  grid-template-rows: 1fr auto;
  padding: clamp(2rem, 6vw, 5rem) var(--gutter) 2.5rem;
  max-width: 1280px;
  margin: 0 auto;
}

.hero__top {
  display: flex;
  align-items: flex-end;
  padding-bottom: clamp(2rem, 6vw, 4rem);
}

.hero__title {
  font-family: var(--serif);
  font-weight: 300;
  font-size: clamp(3rem, 12vw, 9.5rem);
  line-height: 0.95;
  letter-spacing: -0.025em;
}

.hero__title em {
  font-style: italic;
  color: var(--ink-3);
}

.hero__bottom {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
  align-items: end;
}

.hero__sub {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.hero__bio {
  font-family: var(--serif);
  font-size: clamp(1.05rem, 1.6vw, 1.3rem);
  font-weight: 300;
  color: var(--ink-2);
  line-height: 1.55;
  max-width: 48ch;
  justify-self: end;
}

@media (max-width: 720px) {
  .hero__bottom { grid-template-columns: 1fr; }
  .hero__bio { justify-self: start; }
}

/* Featured strip on home */
.featured {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--gutter) var(--section);
}

.featured__head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 2.5rem;
  border-top: 1px solid var(--line);
  padding-top: 2rem;
}

.featured__head h2 {
  font-family: var(--serif);
  font-weight: 300;
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-style: italic;
}

.featured__head a {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-3);
  transition: color 0.3s ease;
}

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

.featured__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(1rem, 2.5vw, 2rem);
}

@media (max-width: 860px) {
  .featured__grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 540px) {
  .featured__grid { grid-template-columns: 1fr; }
}

/* =============================================
   PORTFOLIO
   ============================================= */
.project-list {
  list-style: none;
  border-top: 1px solid var(--line);
}

.project-list li {
  border-bottom: 1px solid var(--line);
}

.project-list a {
  display: grid;
  grid-template-columns: 80px 1fr 1.4fr auto;
  gap: 2rem;
  padding: 1.75rem 0.5rem;
  align-items: baseline;
  transition: background 0.4s ease, padding-left 0.4s ease;
}

.project-list a:hover {
  background: var(--bg-2);
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.project-list .num {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--ink-3);
}

.project-list .title {
  font-family: var(--serif);
  font-size: 1.6rem;
  font-weight: 400;
  letter-spacing: -0.005em;
}

.project-list .title em { font-style: italic; color: var(--ink-3); }

.project-list .meta {
  font-size: 0.85rem;
  color: var(--ink-2);
}

.project-list .year {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--ink-3);
  letter-spacing: 0.1em;
}

@media (max-width: 760px) {
  .project-list a {
    grid-template-columns: 60px 1fr;
    grid-template-rows: auto auto;
    gap: 0.5rem 1rem;
    padding: 1.5rem 0.5rem;
  }
  .project-list .num { grid-row: 1; grid-column: 1; }
  .project-list .title { grid-row: 1; grid-column: 2; font-size: 1.25rem; }
  .project-list .meta { grid-row: 2; grid-column: 2; }
  .project-list .year { grid-row: 2; grid-column: 1; }
}

/* Project tile (image card) */
.tile {
  display: block;
  cursor: pointer;
}

.tile__img {
  aspect-ratio: 4 / 5;
  background: var(--bg-3);
  overflow: hidden;
  position: relative;
  margin-bottom: 1rem;
}

.tile__img > div {
  position: absolute;
  inset: 0;
  transition: transform 0.8s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.tile:hover .tile__img > div { transform: scale(1.04); }

.tile__num {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  color: var(--ink-3);
}

.tile__title {
  font-family: var(--serif);
  font-size: 1.35rem;
  font-weight: 400;
  margin-top: 0.25rem;
  letter-spacing: -0.005em;
}

.tile__title em { font-style: italic; color: var(--ink-3); }

.tile__meta {
  font-size: 0.78rem;
  color: var(--ink-3);
  margin-top: 0.25rem;
  letter-spacing: 0.04em;
}

/* Architecturally-toned placeholder backgrounds (no external images) */
.bg-stone   { background: linear-gradient(135deg, #C7BCA6 0%, #A89A7E 100%); }
.bg-clay    { background: linear-gradient(135deg, #C9A88B 0%, #8E6F55 100%); }
.bg-shadow  { background: linear-gradient(135deg, #6B6256 0%, #2F2A22 100%); }
.bg-fog     { background: linear-gradient(135deg, #DFD5BF 0%, #B8AB8E 100%); }
.bg-rust    { background: linear-gradient(135deg, #B07A5A 0%, #6B3F2A 100%); }
.bg-moss    { background: linear-gradient(135deg, #8A8A6B 0%, #4A4A35 100%); }
.bg-cream   { background: linear-gradient(135deg, #EFE7D5 0%, #C9BFAE 100%); }
.bg-ink     { background: linear-gradient(135deg, #3A332A 0%, #1F1B15 100%); }
.bg-sand    { background: linear-gradient(135deg, #D4C39E 0%, #9C8458 100%); }

/* Subtle architectural overlay — like blueprint hatch */
.tile__img > div::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(0deg,    rgba(255,255,255,0.04) 1px, transparent 1px),
    linear-gradient(90deg,   rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
  mix-blend-mode: overlay;
}

/* =============================================
   RESUME
   ============================================= */
.cv {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: clamp(1.5rem, 5vw, 4rem);
  margin-top: 2rem;
}

@media (max-width: 720px) {
  .cv { grid-template-columns: 1fr; }
}

.cv__section { margin-bottom: 3rem; }

.cv__head {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--ink-3);
  padding-top: 0.6rem;
  border-top: 1px solid var(--line);
}

.cv__body { padding-top: 0.6rem; border-top: 1px solid var(--line); }

.cv__entry {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 1.5rem;
  padding: 1.5rem 0;
  border-bottom: 1px dashed var(--line-soft);
}

.cv__entry:last-child { border-bottom: 0; }

.cv__entry .when {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.06em;
}

.cv__entry .what h3 {
  font-family: var(--serif);
  font-size: 1.3rem;
  font-weight: 400;
  letter-spacing: -0.005em;
  margin-bottom: 0.15rem;
}

.cv__entry .what h3 em { font-style: italic; color: var(--ink-3); }

.cv__entry .where {
  font-size: 0.85rem;
  color: var(--ink-3);
  margin-bottom: 0.6rem;
  letter-spacing: 0.02em;
}

.cv__entry .desc { font-size: 0.92rem; color: var(--ink-2); max-width: 60ch; }

.cv__entry .desc ul { list-style: none; }
.cv__entry .desc li { padding-left: 1rem; position: relative; margin-bottom: 0.25rem; }
.cv__entry .desc li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--ink-3);
}

.tag-row { display: flex; flex-wrap: wrap; gap: 0.5rem 1.5rem; padding-top: 0.5rem; }

.tag-row span {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-2);
  letter-spacing: 0.05em;
}

@media (max-width: 540px) {
  .cv__entry { grid-template-columns: 1fr; gap: 0.4rem; }
}

/* =============================================
   TRAVEL
   ============================================= */
.travel-list {
  list-style: none;
  border-top: 1px solid var(--line);
}

.travel-list li {
  display: grid;
  grid-template-columns: 70px 1.2fr 1fr auto;
  gap: 2rem;
  padding: 1.6rem 0.5rem;
  align-items: baseline;
  border-bottom: 1px solid var(--line);
  transition: background 0.4s ease, padding-left 0.4s ease;
}

.travel-list li:hover {
  background: var(--bg-2);
  padding-left: 1.5rem;
}

.travel-list .yr {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.1em;
}

.travel-list .place {
  font-family: var(--serif);
  font-size: 1.4rem;
  font-weight: 400;
  letter-spacing: -0.005em;
}

.travel-list .place em { font-style: italic; color: var(--ink-3); }

.travel-list .note {
  font-size: 0.88rem;
  color: var(--ink-2);
  font-style: italic;
}

.travel-list .country {
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--ink-3);
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

@media (max-width: 760px) {
  .travel-list li {
    grid-template-columns: 60px 1fr;
    grid-template-rows: auto auto;
    gap: 0.4rem 1rem;
    padding: 1.4rem 0.5rem;
  }
  .travel-list .yr      { grid-row: 1; grid-column: 1; }
  .travel-list .place   { grid-row: 1; grid-column: 2; font-size: 1.2rem; }
  .travel-list .country { grid-row: 2; grid-column: 1; }
  .travel-list .note    { grid-row: 2; grid-column: 2; }
}

/* Photo strip for travel page */
.travel-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: clamp(0.5rem, 1.5vw, 1.25rem);
  margin: 4rem 0;
}

.travel-strip > div {
  aspect-ratio: 3 / 4;
  position: relative;
  overflow: hidden;
}

.travel-strip > div span {
  position: absolute;
  bottom: 0.75rem;
  left: 0.75rem;
  right: 0.75rem;
  color: rgba(255, 255, 255, 0.92);
  font-family: var(--serif);
  font-style: italic;
  font-size: 0.95rem;
  text-shadow: 0 1px 2px rgba(0,0,0,0.4);
}

@media (max-width: 760px) {
  .travel-strip { grid-template-columns: 1fr 1fr; }
}

/* =============================================
   CATS
   ============================================= */
.cats-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: clamp(2rem, 5vw, 4rem);
  margin-top: 2rem;
}

@media (max-width: 720px) { .cats-grid { grid-template-columns: 1fr; } }

.cat-card { display: flex; flex-direction: column; }

.cat-card__img {
  aspect-ratio: 1 / 1;
  margin-bottom: 1.5rem;
  position: relative;
  overflow: hidden;
}

.cat-card__img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.cat-card__num {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  color: var(--ink-3);
  margin-bottom: 0.4rem;
}

.cat-card__name {
  font-family: var(--serif);
  font-size: 2.25rem;
  font-weight: 400;
  letter-spacing: -0.01em;
  margin-bottom: 0.25rem;
}

.cat-card__name em { font-style: italic; color: var(--ink-3); }

.cat-card__meta {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.08em;
  margin-bottom: 1rem;
}

.cat-card__bio {
  font-family: var(--serif);
  font-size: 1.05rem;
  font-weight: 300;
  color: var(--ink-2);
  line-height: 1.6;
  font-style: italic;
}

.cat-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  margin: 4rem 0;
  padding: 2rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.cat-stats div { text-align: center; }
.cat-stats .stat {
  font-family: var(--serif);
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 300;
  letter-spacing: -0.02em;
}
.cat-stats .label {
  font-family: var(--mono);
  font-size: 0.68rem;
  color: var(--ink-3);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  margin-top: 0.4rem;
}

@media (max-width: 540px) {
  .cat-stats { grid-template-columns: 1fr 1fr; gap: 2rem 1rem; }
}

/* =============================================
   FOOTER
   ============================================= */
.footer {
  background: var(--bg-2);
  padding: clamp(3rem, 7vw, 5rem) var(--gutter) 2rem;
  margin-top: var(--section);
  border-top: 1px solid var(--line);
}

.footer__inner {
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.footer__brand {
  font-family: var(--serif);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 300;
  line-height: 1;
  letter-spacing: -0.015em;
}

.footer__brand em { font-style: italic; color: var(--ink-3); }

.footer__brand small {
  display: block;
  font-family: var(--mono);
  font-size: 0.68rem;
  color: var(--ink-3);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  margin-top: 1rem;
}

.footer h4 {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1.25rem;
  font-weight: 400;
}

.footer ul { list-style: none; }
.footer li { margin-bottom: 0.5rem; font-size: 0.92rem; color: var(--ink-2); }
.footer a { transition: color 0.3s ease; }
.footer a:hover { color: var(--ink); }

.footer__bottom {
  max-width: 1280px;
  margin: 3rem auto 0;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--ink-3);
  letter-spacing: 0.12em;
}

@media (max-width: 720px) {
  .footer__inner { grid-template-columns: 1fr; gap: 2rem; }
  .footer__bottom { flex-direction: column; gap: 0.5rem; }
}

/* =============================================
   UTIL
   ============================================= */
.text-center { text-align: center; }
.serif       { font-family: var(--serif); }
.italic      { font-style: italic; }
.muted       { color: var(--ink-3); }
.upper-mono  { font-family: var(--mono); text-transform: uppercase; letter-spacing: 0.2em; font-size: 0.7rem; color: var(--ink-3); }