/* ============================================================
   Sungyoung Moon — personal site
   Apple-inspired design · top nav + left profile sidebar
   Shared by index.html, experience.html, projects.html
   ============================================================ */

/* ---------- Theme tokens ---------- */
:root {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --text-secondary: #55555a;
  --accent: #0071e3;
  --accent-hover: #0077ed;
  --border: rgba(0, 0, 0, 0.08);
  --nav-bg: rgba(251, 251, 253, 0.8);
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  --seg-bg: rgba(0, 0, 0, 0.05);
  --seg-chip-shadow: 0 1px 3px rgba(0, 0, 0, 0.12);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --bg-alt: #161617;
    --card: #1d1d1f;
    --text: #f5f5f7;
    --text-secondary: #c7c7cc;
    --accent: #2997ff;
    --accent-hover: #4aa8ff;
    --border: rgba(255, 255, 255, 0.12);
    --nav-bg: rgba(22, 22, 23, 0.8);
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
  --seg-bg: rgba(255, 255, 255, 0.07);
  --seg-chip-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
  }
}

/* Manual override beats system preference */
:root[data-theme='light'] {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --text-secondary: #55555a;
  --accent: #0071e3;
  --accent-hover: #0077ed;
  --border: rgba(0, 0, 0, 0.08);
  --nav-bg: rgba(251, 251, 253, 0.8);
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  --seg-bg: rgba(0, 0, 0, 0.05);
  --seg-chip-shadow: 0 1px 3px rgba(0, 0, 0, 0.12);
}

:root[data-theme='dark'] {
  --bg: #000000;
  --bg-alt: #161617;
  --card: #1d1d1f;
  --text: #f5f5f7;
  --text-secondary: #c7c7cc;
  --accent: #2997ff;
  --accent-hover: #4aa8ff;
  --border: rgba(255, 255, 255, 0.12);
  --nav-bg: rgba(22, 22, 23, 0.8);
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
  --seg-bg: rgba(255, 255, 255, 0.07);
  --seg-chip-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 4.5rem;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'Segoe UI',
    Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  transition: background 0.3s ease, color 0.3s ease;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

main {
  flex: 1 0 auto;
}

/* Avoid orphan words on wrapped lines; balance multi-line headings */
p,
li {
  text-wrap: pretty;
}

h1,
h2,
h3 {
  text-wrap: balance;
}

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ---------- Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--nav-bg);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 3rem;
  gap: 1rem;
}

.brand {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text);
  text-decoration: none;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.8rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
  white-space: nowrap;
}

.nav-links a:hover {
  color: var(--text);
}

.nav-links a.active {
  color: var(--text);
  font-weight: 600;
}

.theme-toggle {
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 1.05rem;
  cursor: pointer;
  padding: 0.25rem 0.4rem;
  border-radius: 50%;
  line-height: 1;
  transition: color 0.2s ease;
}

.theme-toggle:hover {
  color: var(--text);
}

/* ---------- Two-column layout ---------- */
.layout {
  display: grid;
  grid-template-columns: 300px 1fr;
  gap: 3.5rem;
  align-items: start;
  padding-top: 3rem;
  padding-bottom: 1rem;
}

/* Full-width sections below the profile block (Experience, Projects) */
.content-full {
  padding-bottom: 4rem;
}

/* ---------- Profile sidebar (centered card) ---------- */
.sidebar {
  position: static;
}

.profile-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding-top: 0.5rem;
}

.sidebar-photo {
  width: 170px;
  height: 170px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow: var(--shadow), 0 0 0 5px rgba(41, 151, 255, 0.16);
  display: block;
}

.sidebar-name {
  font-size: 1.65rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  margin-top: 1.25rem;
}

.sidebar-role {
  color: var(--accent);
  font-weight: 600;
  font-size: 1.1rem;
  margin-top: 0.15rem;
}

.sidebar-loc {
  color: var(--text-secondary);
  font-size: 0.98rem;
  margin-top: 0.3rem;
}

.sidebar-divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 1.2rem 0;
  width: 100%;
}

.social-row {
  list-style: none;
  display: flex;
  justify-content: center;
  gap: 0.8rem;
}

.social-row a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  color: var(--text);
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.social-row a:hover {
  background: var(--accent);
  color: #fff;
  transform: translateY(-2px);
}

.social-row svg {
  width: 19px;
  height: 19px;
  fill: currentColor;
}

.btn-resume {
  display: inline-block;
  margin-top: 1.2rem;
  color: var(--accent);
  text-decoration: none;
  font-size: 1.08rem;
  font-weight: 500;
}

.btn-resume::after {
  content: ' ›';
}

.btn-resume:hover {
  text-decoration: underline;
}


/* ---------- Page content (right column) ---------- */
.page-title {
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 1.1rem;
}

.page-lede {
  color: var(--text-secondary);
  font-size: 1.05rem;
  margin-top: -0.5rem;
  margin-bottom: 1.75rem;
}

.lede {
  font-size: 1.2rem;
  line-height: 1.55;
  letter-spacing: -0.01em;
  color: var(--text);
}

.about-body {
  color: var(--text);
  font-size: 1.05rem;
}

.about-body + .about-body {
  margin-top: 1rem;
}

.mini-heading {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-top: 2.25rem;
  margin-bottom: 0.9rem;
}

.section-heading {
  font-size: clamp(1.9rem, 3.5vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin: 3.25rem 0 1.5rem;
}

/* ---------- Skills ---------- */
.skill-lines {
  list-style: none;
}

.skill-lines li {
  font-size: 0.95rem;
  line-height: 1.55;
  color: var(--text-secondary);
}

.skill-lines li + li {
  margin-top: 0.6rem;
}

.skill-lines strong {
  display: block;
  color: var(--text);
  font-weight: 600;
  margin-bottom: 0.15rem;
}

/* ---------- Cards & entries ---------- */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1.4rem 1.6rem;
  box-shadow: var(--shadow);
}

.entry + .entry {
  margin-top: 1.1rem;
}

.entry-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  flex-wrap: wrap;
}

.entry-org {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.entry-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  flex-shrink: 0;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 8px;
}

.entry-logo img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.entry-logo-text {
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text);
}

.entry-head h3 {
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.entry-sub {
  color: var(--text-secondary);
  font-size: 0.92rem;
  margin-top: 0.15rem;
}

.entry-date {
  color: var(--text-secondary);
  font-size: 0.85rem;
  white-space: nowrap;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  padding: 0.15rem 0.7rem;
  border-radius: 980px;
}

.entry-desc {
  margin-top: 0.9rem;
  color: var(--text-secondary);
  font-size: 0.98rem;
}

.entry-points {
  margin-top: 0.6rem;
  padding-left: 1.25rem;
  font-size: 0.95rem;
}

.entry-points li {
  margin-top: 0.4rem;
}

/* ---------- Experience list (timeline + card boxes) ---------- */
.xp-list {
  display: flex;
  flex-direction: column;
  position: relative;
  padding-left: 2.25rem;
}

.xp-list::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 28px;
  bottom: 28px;
  width: 2px;
  background: var(--border);
}

.xp-item {
  display: flex;
  gap: 1.4rem;
  padding: 2rem 2.25rem;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 22px;
  box-shadow: var(--shadow);
  position: relative;
}

.xp-featured {
  border-color: rgba(41, 151, 255, 0.35);
  background: linear-gradient(180deg, rgba(41, 151, 255, 0.06), rgba(41, 151, 255, 0) 55%), var(--card);
}

.xp-item::before {
  content: '';
  position: absolute;
  left: calc(-2.25rem + 1px);
  top: 3.2rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--accent);
}

.xp-item + .xp-item {
  margin-top: 1.5rem;
}

.xp-logo {
  width: 56px;
  height: 56px;
  padding: 7px;
  border-radius: 13px;
}

.xp-body {
  flex: 1;
  min-width: 0;
}

.xp-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  flex-wrap: wrap;
}

.xp-eyebrow {
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--text-secondary);
}

.xp-head {
  margin-top: 0.25rem;
}

.xp-head h3 {
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: -0.015em;
}

.xp-date {
  color: var(--text-secondary);
  font-size: 0.85rem;
  white-space: nowrap;
}

.xp-gist {
  font-size: 1rem;
  line-height: 1.6;
  margin-top: 0.6rem;
}

.xp-item .disclosure {
  margin-top: 0.45rem;
}

.xp-notes {
  list-style: none;
  margin-top: 0.5rem;
  color: var(--text);
  font-size: 0.95rem;
}

.xp-notes li {
  margin-top: 0.15rem;
}

.xp-points {
  margin-top: 0.9rem;
}

.xp-points li {
  margin-top: 0.6rem;
  line-height: 1.6;
}

/* ---------- Disclosure (Details / Highlights / Coursework) ---------- */
.disclosure {
  margin-top: 0.9rem;
}

.disclosure summary {
  cursor: pointer;
  color: var(--accent);
  font-weight: 500;
  font-size: 0.9rem;
  list-style: none;
  -webkit-user-select: none;
  user-select: none;
}

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

.disclosure summary::after {
  content: '›';
  display: inline-block;
  margin-left: 0.4rem;
  width: 0.6em;
  text-align: center;
  transform-origin: center;
  transition: transform 0.2s ease;
}

.disclosure[open] summary::after {
  transform: rotate(90deg);
}

/* Opened Highlights: inset panel with accent bullets */
.project-card .disclosure .entry-points {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.9rem 1.1rem 1rem 2rem;
  margin-top: 0.7rem;
}

.project-card .disclosure .entry-points li {
  margin-top: 0.55rem;
  line-height: 1.55;
}

.project-card .disclosure .entry-points li:first-child {
  margin-top: 0;
}

.project-card .disclosure .entry-points li::marker {
  color: var(--accent);
}

.course-list {
  margin-top: 0.6rem;
  padding-left: 1.25rem;
  columns: 2;
  column-gap: 2rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.course-list li {
  margin-top: 0.3rem;
  break-inside: avoid;
}

/* ---------- Two-column row (Education | Skills on home) ---------- */
.two-col {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 1.25rem;
  align-items: stretch;
  margin-top: 2rem;
}

.two-col-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1.4rem 1.6rem;
  box-shadow: var(--shadow);
}

.two-col-card .mini-heading {
  margin-top: 0;
}

.two-col .course-list {
  columns: 1;
}

@media (max-width: 900px) {
  .two-col {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }
}

/* ---------- Compact education rows (home) ---------- */
.edu-list {
  list-style: none;
}

.edu-row {
  display: flex;
  align-items: flex-start;
  gap: 0.9rem;
}

.edu-row + .edu-row {
  margin-top: 1rem;
}

.edu-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 5px;
}

.edu-logo img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.edu-logo-flat {
  padding: 0;
  background: none;
  border: none;
  overflow: hidden;
}

.edu-logo-flat img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 10px;
}

.edu-degree {
  font-weight: 600;
  font-size: 1rem;
}

.edu-school {
  color: var(--text-secondary);
  font-size: 0.92rem;
  margin-top: 0.1rem;
}

.edu-row .disclosure {
  margin-top: 0.35rem;
}

/* ---------- Activities (home) ---------- */
.activity-list {
  list-style: none;
}

.activity-list li {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  font-size: 0.92rem;
  margin-top: 0.45rem;
}

.activity-list em {
  font-style: normal;
  color: var(--text-secondary);
}

.activity-date {
  color: var(--text-secondary);
  font-size: 0.85rem;
  white-space: nowrap;
}

/* ---------- Now card (home) ---------- */
.now-card {
  display: flex;
  align-items: center;
  gap: 1.1rem;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 1.4rem 1.6rem;
  box-shadow: var(--shadow);
  margin-top: 2.25rem;
}

.now-eyebrow {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
}

.now-text {
  font-size: 0.98rem;
  margin-top: 0.15rem;
}

.now-link {
  display: inline-block;
  margin-top: 0.35rem;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
}

.now-link:hover {
  text-decoration: underline;
}

/* ---------- Projects ---------- */
.project-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.project-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.project-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 60px;
  height: 60px;
  flex-shrink: 0;
  border-radius: 14px;
  font-size: 1.8rem;
  box-shadow: var(--shadow);
}

.project-icon-img {
  object-fit: contain;
  background: none;
  box-shadow: var(--shadow);
  border-radius: 14px;
}

.project-tag {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  margin-top: 0.9rem;
}

.project-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.015em;
  margin-top: 0.25rem;
}

.project-tagline {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-top: 0.3rem;
}

.project-card .disclosure {
  margin-top: 0.75rem;
}

.project-media {
  width: 100%;
  height: auto;
  border-radius: 12px;
  border: 1px solid var(--border);
  margin-bottom: 0.9rem;
}

.project-link {
  margin-top: 0.75rem;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
}

.project-link:hover {
  text-decoration: underline;
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 1.5rem 0 2.5rem;
  color: var(--text-secondary);
  font-size: 0.8rem;
  text-align: center;
}

.footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1.25rem;
  list-style: none;
  margin-bottom: 0.6rem;
}

.footer-links a {
  color: var(--accent);
  text-decoration: none;
}

.footer-links a:hover {
  text-decoration: underline;
}

/* ---------- Scroll reveal (Apple-style) ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.8s cubic-bezier(0.25, 0.1, 0.25, 1),
    transform 0.8s cubic-bezier(0.25, 0.1, 0.25, 1);
  will-change: opacity, transform;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

.reveal-now {
  animation: rise-in 0.9s cubic-bezier(0.25, 0.1, 0.25, 1) both;
}

@keyframes rise-in {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  .reveal,
  .reveal-now {
    opacity: 1;
    transform: none;
    transition: none;
    animation: none;
  }
}

/* ---------- Mobile ---------- */
@media (max-width: 760px) {
  html {
    scroll-padding-top: 4.5rem;
  }

  body {
    overflow-x: clip;
  }

  .container {
    padding: 0 1.1rem;
  }

  /* Nav: one row with a segmented control. The brand is hidden because the
     profile block repeats the name directly below it on a narrow screen. */
  .nav {
    height: 3.15rem;
    justify-content: center;
    position: relative;
  }

  .brand {
    display: none;
  }

  .theme-toggle {
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
  }

  .nav-links {
    gap: 0.15rem;
    padding: 0.2rem;
    background: var(--seg-bg);
    border-radius: 980px;
  }

  .nav-links a {
    display: block;
    font-size: 0.78rem;
    font-weight: 500;
    padding: 0.34rem 0.62rem;
    border-radius: 980px;
    transition: background 0.2s ease, color 0.2s ease;
  }

  .nav-links a.active {
    color: var(--text);
    font-weight: 600;
    background: var(--card);
    box-shadow: var(--seg-chip-shadow);
  }

  .layout {
    grid-template-columns: 1fr;
    gap: 2.25rem;
    padding-top: 2.25rem;
  }

  .sidebar {
    position: static;
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .sidebar-photo {
    width: 150px;
    height: 150px;
  }

  /* Experience: no timeline rail, tighter cards */
  .xp-list {
    padding-left: 0;
  }

  .xp-list::before,
  .xp-item::before {
    display: none;
  }

  .xp-item {
    flex-direction: column;
    gap: 0.9rem;
    padding: 1.35rem 1.2rem;
    border-radius: 18px;
  }

  .xp-logo {
    width: 48px;
    height: 48px;
  }

  .xp-head {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.15rem;
  }

  .xp-head h3 {
    font-size: 1.15rem;
  }

  .xp-eyebrow {
    font-size: 0.72rem;
  }

  .entry-points,
  .xp-points {
    padding-left: 1.1rem;
  }

  /* Cards & sections */
  .two-col-card,
  .card {
    padding: 1.35rem 1.2rem;
  }

  .section-heading {
    margin: 2.5rem 0 1.1rem;
  }

  .project-grid {
    grid-template-columns: 1fr;
  }

  .project-card .disclosure .entry-points {
    padding: 0.8rem 0.9rem 0.9rem 1.7rem;
  }

  .footer-links {
    gap: 0.9rem;
  }
}

@media (max-width: 640px) {
  .course-list {
    columns: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  body,
  .disclosure summary::after,
  .btn-resume,
  .theme-toggle,
  .nav-links a {
    transition: none;
  }
}