/* ============================================================
   style.css — Portfolio Index (Dark + Emerald Theme)
   ============================================================ */

/* ── 1. Custom Properties ─────────────────────────────────── */
:root {
  --bg-dark:       #0a0a0a;
  --bg-surface:    #111111;
  --bg-hover:      #181818;
  --text-main:     #f3f4f6;
  --text-muted:    #9ca3af;
  --text-faint:    #858b98;
  --accent:        #34d399;
  --accent-dim:    rgba(52, 211, 153, 0.10);
  --accent-border: rgba(52, 211, 153, 0.25);
  --border:        #27272a;
  --border-hover:  #3f3f46;
  --sidebar-pad:   64px;
  --content-pt:    160px;   /* Seera 스타일 상단 여백 */
  --ease-out:      cubic-bezier(0.16, 1, 0.3, 1);
  --font-base:     'Pretendard Variable', 'Pretendard', -apple-system, BlinkMacSystemFont, 'Noto Sans KR', sans-serif;
}

/* ── 1b. Light Theme Override ────────────────────────────── */
[data-theme="light"] {
  --bg-dark:       #f8f9fa;
  --bg-surface:    #ffffff;
  --bg-hover:      #f1f3f5;
  --text-main:     #111111;
  --text-muted:    #4b5563;
  --text-faint:    #667085;
  --accent:        #059669;          /* 에메랄드 다크 — 흰 배경에서 가독성 */
  --accent-dim:    rgba(5, 150, 105, 0.08);
  --accent-border: rgba(5, 150, 105, 0.22);
  --border:        #e5e7eb;
  --border-hover:  #d1d5db;
}

[data-theme="light"] body {
  background-color: var(--bg-dark);
  color: var(--text-main);
}

[data-theme="light"] .sidebar {
  border-right: 1px solid var(--border);
}

[data-theme="light"] .content::before {
  background: radial-gradient(circle, rgba(5, 150, 105, 0.05) 0%, transparent 70%);
}

[data-theme="light"] .back-to-top {
  background: var(--bg-surface);
  border-color: var(--border-hover);
}

[data-theme="light"] .mobile-nav {
  background: rgba(248, 249, 250, 0.92);
  border-color: var(--border);
}

/* ── 2. Reset & Base ─────────────────────────────────────── */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-base);
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  word-break: keep-all;
  overflow-x: hidden;
}

a    { text-decoration: none; color: inherit; }
li   { list-style: none; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
.skip-link { position: fixed; top: 8px; left: 8px; z-index: 1000; padding: 10px 14px; background: var(--text-main); color: var(--bg-dark); border-radius: 8px; transform: translateY(-150%); }
.skip-link:focus { transform: translateY(0); }

/* ── 3. Split Layout ─────────────────────────────────────── */
.split-layout {
  display: flex;
  min-height: 100vh;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 30px;
  gap: 80px;    /* Seera: gap 80px */
}

/* ── 4. Sidebar ─────────────────────────────────────────── */
.sidebar {
  width: min-content;
  min-width: 280px;
  padding: var(--content-pt) 0 80px;
  flex-shrink: 0;
}

.sidebar-inner {
  position: sticky;
  top: 64px;
  height: calc(100vh - 128px);
  display: flex;
  flex-direction: column;
  gap: 40px;
}

/* ── 5. Profile Header ───────────────────────────────────── */
.profile-img {
  width: 210px;
  height: 210px;
  border-radius: 12px;
  object-fit: cover;
  border: 2px solid var(--border);
  margin-bottom: 20px;
  display: block;
}

.role {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}

.name {
  font-size: 3rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.1;
  margin-bottom: 18px;
  white-space: nowrap;
}

.bio {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.8;
  max-width: 260px;
}

/* ── 6. Section Nav ─────────────────────────────────────── */
.section-nav ul {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: 8px 0;
  transition: color 0.2s ease;
}

.nav-link::before {
  content: '';
  display: block;
  width: 24px;
  height: 1px;
  background: var(--text-muted);
  flex-shrink: 0;
  transition: width 0.3s var(--ease-out), background 0.2s ease;
}

.nav-link:hover { color: var(--text-main); }
.nav-link:hover::before { width: 44px; background: var(--text-main); }

.nav-link.is-active { color: var(--accent); }
.nav-link.is-active::before { width: 44px; background: var(--accent); }

/* ── 7. Sidebar Footer ───────────────────────────────────── */
.sidebar-footer {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.resume-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-main);
  padding-bottom: 5px;
  border-bottom: 1.5px solid transparent;
  transition: border-color 0.25s ease, gap 0.25s ease;
}

.resume-btn:hover {
  border-bottom-color: var(--accent);
  gap: 18px;
}

.social-links {
  display: flex;
  gap: 18px;
}

.social-links a {
  font-size: 0.85rem;
  color: var(--text-faint);
  font-weight: 500;
  transition: color 0.2s;
}

.social-links a:hover { color: var(--accent); }

/* ── 8. Content Area ─────────────────────────────────────── */
.content {
  flex: 1;
  min-width: 0;
  padding: var(--content-pt) 0 120px;
  position: relative;
}

/* 배경 글로우 오브 (Seera 스타일) */
.content::before {
  content: '';
  position: absolute;
  top: 80px;
  right: -60px;
  width: 480px;
  height: 480px;
  background: radial-gradient(circle, rgba(52, 211, 153, 0.07) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}

/* ── 9. Section 공통 ─────────────────────────────────────── */
.section {
  padding-top: 64px;
  position: relative;
  z-index: 1;
}

.section:first-child {
  padding-top: 0;
}

.section-label {
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 28px;
}

/* ── 10. About Section ───────────────────────────────────── */
.about-hook {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-main);
  line-height: 1.6;
  margin-bottom: 28px;
  padding-left: 16px;
  border-left: 3px solid var(--accent);
}

.about-text {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.9;
}

.about-text + .about-text {
  margin-top: 20px;
}

.about-text em {
  font-style: normal;
  color: var(--text-main);
  font-weight: 600;
}

.about-project-link {
  border-bottom: 1px solid var(--text-main);
  padding-bottom: 1px;
  box-decoration-break: clone;
  -webkit-box-decoration-break: clone;
  transition: color 0.2s, border-color 0.2s;
}

.about-project-link:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ── 11. Skills Section ──────────────────────────────────── */


.skills-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px 32px;
}

.skill-category {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.skill-cat-title {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.skill-tags li {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--text-muted);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  padding: 5px 11px;
  border-radius: 8px;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
  cursor: default;
}

.skill-tags li::before {
  content: '';
  display: block;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  flex-shrink: 0;
  transition: transform 0.2s;
}

.skill-tags li:hover {
  background: var(--bg-hover);
  border-color: var(--border-hover);
  color: var(--text-main);
}

.skill-tags li:hover::before {
  transform: scale(1.5);
}

/* ── 11b. Career Section ──────────────────────────────────── */
.career-block + .career-block {
  margin-top: 36px;
}

.career-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 6px;
}

.career-company-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.career-company-name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
}

.career-role-badge {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  padding: 2px 8px;
  border-radius: 20px;
}

.career-total-period {
  font-size: 0.72rem;
  color: var(--text-faint);
}

.career-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.career-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 16px;
  border-radius: 10px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s, transform 0.2s;
  position: relative;
}

.career-item:not(a) { cursor: default; }

.career-item:hover {
  background: var(--bg-surface);
  border-color: var(--border);
  transform: translateX(4px);
}

.career-item:hover .career-item-arrow {
  color: var(--accent);
  transform: translateX(3px);
}

.career-item:hover .career-item-title {
  color: var(--accent);
}

.career-item-left {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 5px;
  min-width: 108px;
  flex-shrink: 0;
  padding-top: 2px;
}

.career-item-period {
  font-size: 0.68rem;
  color: var(--text-faint);
  white-space: nowrap;
  text-align: right;
}

.career-badge {
  font-size: 0.62rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  padding: 2px 7px;
  border-radius: 20px;
  white-space: nowrap;
}

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

.career-item-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 5px;
  transition: color 0.2s;
}

.career-item-sub {
  font-size: 0.75rem;
  font-weight: 400;
  color: var(--text-faint);
  margin-left: 6px;
}

.career-item-desc {
  font-size: 0.76rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 8px;
}

.career-item-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
  list-style: none;
  padding: 0;
  margin: 0;
}

.career-item-stack li {
  font-size: 0.68rem;
  color: var(--text-faint);
  background: var(--bg-hover);
  border: 1px solid var(--border);
  padding: 2px 8px;
  border-radius: 4px;
}

.career-item-arrow {
  font-size: 1rem;
  color: var(--text-faint);
  transition: color 0.2s, transform 0.2s;
  flex-shrink: 0;
  margin-top: 2px;
}

/* ── Career Education (Expandable) ────────────────────────── */
.career-education {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s var(--ease-out), opacity 0.3s ease;
  opacity: 0;
}

.career-education.is-open {
  opacity: 1;
}

.education-entry {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 14px 16px;
  border-radius: 10px;
  border: 1px solid transparent;
  transition: background 0.2s, border-color 0.2s;
}

.education-entry:hover {
  background: var(--bg-surface);
  border-color: var(--border);
}

.education-left {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  min-width: 108px;
  flex-shrink: 0;
  padding-top: 2px;
}

.education-period {
  font-size: 0.68rem;
  color: var(--text-faint);
  white-space: nowrap;
  text-align: right;
}

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

.education-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 4px;
}

.education-desc {
  font-size: 0.76rem;
  color: var(--text-muted);
  line-height: 1.65;
}

.career-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  width: 100%;
  padding: 12px 0 4px;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-faint);
  font-size: 0.72rem;
  font-weight: 600;
  font-family: var(--font-base);
  letter-spacing: 0.06em;
  transition: color 0.2s;
}

.career-toggle:hover {
  color: var(--accent);
}

.career-toggle-icon {
  transition: transform 0.3s var(--ease-out);
}

.career-toggle[aria-expanded="true"] .career-toggle-icon {
  transform: rotate(180deg);
}

/* ── Side Projects Grid ───────────────────────────────────── */
.projects-more-link {
  font-size: 0.75rem;
  color: var(--accent);
  text-decoration: none;
  transition: opacity 0.2s;
}

.projects-more-link:hover { opacity: 0.75; }

/* Side Project Slider */
.side-project-slider {
  overflow-x: clip;
  overflow-y: visible;
  padding: 8px 0;
  margin: -8px 0;
}

.side-project-track {
  display: flex;
  gap: 14px;
  transition: transform 0.35s var(--ease-out);
  will-change: transform;
  cursor: grab;
  user-select: none;
  -webkit-user-select: none;
}

.side-project-track.is-dragging {
  cursor: grabbing;
  transition: none;
}

.side-project-track .side-project-card {
  /* 3개 표시 + 4번째 살짝 걸침: (100% - gap*2) / 3.4 */
  min-width: calc((100% - 14px * 2) / 3.4);
  max-width: calc((100% - 14px * 2) / 3.4);
  flex-shrink: 0;
}

.side-project-nav {
  display: flex;
  gap: 8px;
  margin-top: 16px;
}

.side-project-btn {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-faint);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s, background 0.2s;
}

.side-project-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
}

.side-project-btn:disabled {
  opacity: 0.3;
  cursor: default;
  pointer-events: none;
}

.side-project-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.side-project-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px;
  cursor: pointer;
  transition: border-color 0.2s, transform 0.2s, box-shadow 0.2s;
  position: relative;
  overflow: hidden;
}

.side-project-card:hover {
  border-color: var(--accent-border);
  transform: translateY(-4px);
  box-shadow: 0 4px 14px rgba(0,0,0,0.2);
}

.side-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.side-card-primary { display: block; }

.side-card-github {
  color: var(--text-faint);
  transition: color 0.2s;
}

.side-project-card:hover .side-card-github {
  color: var(--accent);
}

/* ── GitHub Corner (bottom-right diagonal) ── */
.side-card-corner {
  position: absolute;
  right: 0;
  bottom: 0;
  width: 72px;
  height: 72px;
  display: flex;
  align-items: flex-end;
  justify-content: flex-end;
  text-decoration: none;
  z-index: 2;
}

.side-card-corner-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 50%, var(--accent) 50%);
  opacity: 0.15;
  transition: opacity 0.25s ease;
  border-bottom-right-radius: 11px;
}

.side-card-corner:hover .side-card-corner-bg {
  opacity: 0.35;
}

.side-card-corner-content {
  position: relative;
  display: flex;
  align-items: center;
  gap: 3px;
  padding: 6px 8px;
  color: var(--accent);
  transition: color 0.2s, transform 0.2s;
}

.side-card-corner:hover .side-card-corner-content {
  color: var(--text-main);
  transform: translate(-1px, -1px);
}

.side-card-corner-label {
  font-size: 0.58rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.side-card-year {
  font-size: 0.68rem;
  color: var(--text-faint);
}

.side-card-title {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 6px;
}

.side-card-desc {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 12px;
}

.side-card-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
  list-style: none;
  padding: 0;
  margin: 0;
}

.side-card-stack li {
  font-size: 0.65rem;
  color: var(--text-faint);
  background: var(--bg-hover);
  border: 1px solid var(--border);
  padding: 2px 7px;
  border-radius: 4px;
}

/* ── 12. Projects Section ────────────────────────────────── */
.projects-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}

.projects-header .section-label {
  margin-bottom: 0;
}

.carousel-controls {
  display: flex;
  gap: 8px;
}

.carousel-btn {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-faint);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s, background 0.2s;
  flex-shrink: 0;
}

.carousel-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
}

.carousel-btn:disabled {
  opacity: 0.3;
  cursor: default;
  pointer-events: none;
}

/* 캐러셀 뷰포트 — overflow hidden으로 클립 */
.carousel-wrapper {
  overflow: hidden;
}

.project-carousel {
  display: grid;
  /*
   * 2행 × N열 캐러셀:
   *  - 데스크탑: 열 너비 약 46%, 2열 완전히 보이고 우측에 다음 열 살짝 걸침
   *  - grid-auto-flow: column → 카드가 세로로 먼저 채워짐
   *    (카드1→행1열1, 카드2→행2열1, 카드3→행1열2, 카드4→행2열2)
   */
  /*
   * 열 너비: 약 63%
   * → 1열이 완전히 보이고, 2번째 열의 약 30%가 우측에 걸쳐 미리보기
   * → 슬라이드하면 다음 열(카드 3,4)이 완전히 보임
   */
  grid-template-columns: repeat(2, calc(63% - 7px));
  grid-auto-columns: calc(63% - 7px);
  grid-auto-flow: column;
  grid-template-rows: repeat(2, auto);
  gap: 14px;
  transition: transform 0.45s var(--ease-out);
  will-change: transform;
  cursor: grab;
  user-select: none;
  -webkit-user-select: none;
}

.project-carousel.is-dragging {
  cursor: grabbing;
  transition: none;
}

/* 인디케이터 점 */
.carousel-dots {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-top: 20px;
}

.carousel-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--border-hover);
  border: none;
  padding: 0;
  cursor: pointer;
  transition: background 0.2s, transform 0.2s;
}

.carousel-dot.is-active {
  background: var(--accent);
  transform: scale(1.4);
}

/* 카드: float 호버 애니메이션 */
@keyframes card-float {
  0%   { transform: translateY(0); }
  50%  { transform: translateY(-6px); }
  100% { transform: translateY(0); }
}

.project-card {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 24px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  cursor: pointer;
  position: relative;
  overflow: hidden;
  transition: border-color 0.3s ease;
}

.project-card:hover {
  border-color: var(--border-hover);
  animation: card-float 0.7s var(--ease-out) forwards;
}

.card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 16px;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 8px;
}

.year {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-faint);
}

.duration {
  font-size: 0.75rem;
  color: var(--text-faint);
}

.badge {
  display: inline-block;
  font-size: 0.66rem;
  font-weight: 700;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid var(--accent-border);
  padding: 3px 9px;
  border-radius: 20px;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.card-link-hint {
  font-size: 0.95rem;
  color: var(--text-faint);
  transition: color 0.2s, transform 0.25s var(--ease-out);
  line-height: 1;
  position: relative;
  z-index: 1;
}

.project-card:hover .card-link-hint {
  color: var(--accent);
  transform: translate(4px, -4px);
}

.project-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-main);   /* 흰색으로 — 에메랄드는 accent-dim 배경으로 충분 */
  margin-bottom: 8px;
  line-height: 1.3;
}

.project-subtitle {
  display: block;
  font-size: 0.82rem;
  font-weight: 400;
  color: var(--text-faint);
  margin-top: 2px;
}

.project-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.75;
  margin-bottom: 20px;
  flex: 1;
}

.tech-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: auto;
}

.tech-stack li {
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--text-faint);
  background: transparent;
  border: 1px solid var(--border);
  padding: 3px 10px;
  border-radius: 20px;
  transition: border-color 0.2s, color 0.2s;
}

.project-card:hover .tech-stack li {
  border-color: var(--border-hover);
  color: var(--text-muted);
}

/* ── 13. Contact Section ─────────────────────────────────── */
.contact-desc {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: 40px;
  line-height: 1.8;
}

.contact-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.contact-list li {
  display: flex;
  align-items: center;
  gap: 0;
  padding: 18px 0;
  border-bottom: 1px solid var(--border);
  transition: border-color 0.2s;
}

.contact-list li:first-child {
  border-top: 1px solid var(--border);
}

.contact-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
  width: 80px;
  flex-shrink: 0;
}

.contact-link {
  font-size: 0.95rem;
  color: var(--text-muted);
  transition: color 0.2s;
}

.contact-link:hover { color: var(--accent); }

/* ── 14. Mobile Floating Nav ────────────────────────────── */
.mobile-nav { display: none; }

/* ── 14b. Back to Top Button ─────────────────────────────── */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  z-index: 100;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--border-hover);
  background: var(--bg-surface);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition:
    opacity 0.3s ease,
    transform 0.3s ease,
    border-color 0.2s,
    color 0.2s,
    background 0.2s;
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.back-to-top:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
}

/* ── 14c. Theme Toggle Button ────────────────────────────── */
.theme-toggle {
  position: fixed;
  bottom: 88px;    /* back-to-top 버튼 위 */
  right: 32px;
  z-index: 100;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--border-hover);
  background: var(--bg-surface);
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition:
    border-color 0.2s,
    color 0.2s,
    background 0.2s;
}

.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-dim);
}

/* 아이콘 전환 */
.theme-toggle .icon-moon { display: block; }
.theme-toggle .icon-sun  { display: none; }

[data-theme="light"] .theme-toggle .icon-moon { display: none; }
[data-theme="light"] .theme-toggle .icon-sun  { display: block; }

/* ── 15. Scroll Reveal ───────────────────────────────────── */
.reveal {
  opacity: 1;
  transform: none;
}

.js .reveal {
  opacity: 0;
  transform: translateY(20px);
  transition:
    opacity 0.6s var(--ease-out),
    transform 0.6s var(--ease-out);
}

.js .reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── 16. Responsive ─────────────────────────────────────── */

/* 1080px 이하: 단일 컬럼 */
@media (max-width: 1080px) {
  .split-layout {
    flex-direction: column;
    gap: 0;
    padding: 0 32px;
  }

  .sidebar {
    width: 100%;
    min-width: unset;
    padding: 60px 0 40px;
  }

  .sidebar-inner {
    position: static;
    height: auto;
    gap: 28px;
  }

  .sidebar-footer { margin-top: 0; }

  .name { font-size: 2.4rem; white-space: normal; }
  .bio  { max-width: 100%; }

  .section-nav { display: none; }

  /* 모바일 플로팅 Nav */
  .mobile-nav {
    display: block;
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 200;
    background: rgba(17, 17, 17, 0.9);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-hover);
    border-radius: 40px;
    padding: 10px 24px;
  }

  .mobile-nav ul {
    display: flex;
    gap: 20px;
    align-items: center;
  }

  .mobile-nav a {
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-muted);
    transition: color 0.2s;
  }

  .mobile-nav a:hover,
  .mobile-nav a.is-active { color: var(--accent); }

  .content {
    padding: 0 0 100px;
  }

  .content::before { display: none; }

  .section { padding-top: 80px; }
  .section:first-child { padding-top: 72px; }

  .project-carousel {
    /* 모바일: 1열 보이고 우측에 다음 카드 미리보기 */
    grid-template-columns: calc(75% - 7px);
    grid-auto-columns: calc(75% - 7px);
    grid-template-rows: repeat(2, auto);
  }

  .skills-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

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

  .side-project-track .side-project-card {
    min-width: calc(80% - 7px);
    max-width: calc(80% - 7px);
  }

  .career-item-left {
    min-width: 90px;
  }

  .education-left {
    min-width: 90px;
  }

  .back-to-top { bottom: 24px; right: 20px; }
}

/* 480px: 모바일 소형 */
@media (max-width: 480px) {
  .split-layout { padding: 0 20px; }
  .sidebar { padding: 48px 0 32px; }

  .name { font-size: 2rem; }

  .mobile-nav { padding: 9px 18px; }
  .mobile-nav ul { gap: 14px; }
  .mobile-nav a { font-size: 0.7rem; }

  .project-carousel {
    grid-template-columns: calc(80% - 6px);
    grid-auto-columns: calc(80% - 6px);
    gap: 12px;
  }

  .skills-grid { gap: 20px; }

  .career-item {
    flex-direction: column;
    gap: 8px;
  }

  .career-item-left {
    flex-direction: row;
    align-items: center;
    min-width: unset;
  }

  .career-item-arrow { display: none; }

  .education-entry {
    flex-direction: column;
    gap: 8px;
  }

  .education-left {
    flex-direction: row;
    align-items: center;
    min-width: unset;
  }

  .side-project-track .side-project-card {
    min-width: calc(85% - 6px);
    max-width: calc(85% - 6px);
  }

  .contact-list li { gap: 0; }
  .contact-label { width: 70px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .side-project-track, .career-education { transition: none; }
}