/* ============================================================
   2024 충북 스마트농업 심포지엄 — Light Editorial
   밝은 화이트/파치먼트 캔버스 · 딥 그린 단일 액센트 · 사진 우선
   ============================================================ */

:root {
  /* 액센트 (무채색 통일 — 잉크) */
  --green:        #18181b;
  --green-deep:   #000000;
  --green-ink:    #18181b;   /* 라이트 위 텍스트 = 잉크 */
  --green-soft:   #ececeb;   /* 중립 틴트 */
  --main:         #00adbb;   /* 포인트 색 (타이틀 박스 · 섹션 키커) */

  /* 잉크 / 뉴트럴 */
  --ink:          #18181b;
  --ink-body:     #52525b;
  --ink-muted:    #8e8e96;
  --line:         #e6e6e4;
  --line-strong:  #d6d6d3;

  /* 표면 */
  --canvas:       #ffffff;
  --paper:        #f5f5f4;
  --paper-2:      #ececeb;

  /* 다크 타일 (영상 밴드 / 푸터) */
  --dark:         #1a1a1d;
  --dark-2:       #232327;
  --on-dark:      #ffffff;
  --on-dark-muted:#a1a1aa;

  /* radius */
  --r-sm: 10px;
  --r-md: 16px;
  --r-lg: 24px;
  --r-btn: 12px;
  --r-pill: 999px;

  /* 그림자 (사진/모달 한정) */
  --shadow-photo: 0 22px 60px -24px rgba(18,28,22,.45);
  --shadow-pop:   0 -8px 40px rgba(0,0,0,.18);

  /* 모션 */
  --ease: cubic-bezier(.32,.72,0,1);
  --t: .22s var(--ease);

  /* spacing (8px) */
  --sp-1:4px; --sp-2:8px; --sp-3:12px; --sp-4:16px; --sp-5:24px;
  --sp-6:32px; --sp-7:48px; --sp-8:64px; --sp-9:80px; --sp-10:104px;

  /* 컨테이너 */
  --w:1160px; --w-text:880px; --w-wide:1280px;

  /* 타입 */
  --fs-display: clamp(40px, 6vw, 84px);
  --fs-h2:      clamp(27px, 3.4vw, 42px);
  --fs-h3:      clamp(20px, 2vw, 24px);
  --fs-lead:    clamp(18px, 1.8vw, 21px);
  --fs-body:    17px;
  --fs-sub:     15px;
  --fs-cap:     13.5px;
  --fs-label:   12px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: 'Inter', 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Apple SD Gothic Neo', sans-serif;
  font-size: var(--fs-body);
  font-weight: 400;
  line-height: 1.72;
  color: var(--ink-body);
  background: var(--canvas);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

::selection { background: var(--green); color: #fff; }

/* 포커스 링 */
:where(a,button,[role="button"],[tabindex]):focus-visible {
  outline: 3px solid var(--green);
  outline-offset: 3px;
  border-radius: 6px;
}

/* Skip link */
.skip-link {
  position: absolute; left: 50%; top: 10px;
  transform: translateX(-50%) translateY(-200%);
  z-index: 1200;
  background: var(--ink); color: #fff;
  padding: 10px 20px; border-radius: var(--r-pill);
  font-size: 14px; font-weight: 600; text-decoration: none;
  transition: transform var(--t);
}
.skip-link:focus { transform: translateX(-50%) translateY(0); }

/* ── 공통 ─────────────────────────────────── */
.section { padding: var(--sp-9) 0; }
.container { max-width: var(--w); margin: 0 auto; padding: 0 28px; }
.container.text { max-width: var(--w-text); }
.container.wide { max-width: var(--w-wide); }

.sec-head { margin-bottom: var(--sp-7); }
.sec-head.center { text-align: center; }
.sec-kicker {
  display: inline-block;
  font-size: var(--fs-label);
  font-weight: 700;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--main);
  margin-bottom: 14px;
}
.sec-title {
  font-size: var(--fs-h2);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.15;
  color: var(--ink);
}
.sec-desc {
  margin-top: 16px;
  font-size: var(--fs-lead);
  color: var(--ink-muted);
  max-width: 560px;
  font-weight: 300;
  letter-spacing: -0.01em;
}
.sec-head.center .sec-desc { margin-left: auto; margin-right: auto; }
.on-dark .sec-title { color: var(--on-dark); }
.on-dark .sec-kicker { color: var(--main); }
.on-dark .sec-desc { color: var(--on-dark-muted); }

/* ── 버튼 ─────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: inherit; font-size: var(--fs-sub); font-weight: 600;
  padding: 13px 24px; border-radius: var(--r-btn);
  cursor: pointer; text-decoration: none; border: 1px solid transparent;
  transition: background var(--t), border-color var(--t), color var(--t);
}
.btn svg { width: 17px; height: 17px; }
.btn-primary { background: var(--green); color: #fff; border-color: var(--green); }
.btn-primary:hover { background: var(--green-deep); border-color: var(--green-deep); }
.btn-primary:active { transform: scale(.97); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line-strong); }
.btn-ghost:hover { background: var(--paper); border-color: var(--ink-muted); }
.btn-ghost:active { transform: scale(.97); }
.btn-on-dark { background: rgba(255,255,255,.1); color: #fff; border-color: rgba(255,255,255,.22); }
.btn-on-dark:hover { background: rgba(255,255,255,.18); }
.btn-on-dark:active { transform: scale(.97); }

/* ── NAV ──────────────────────────────────── */
.nav {
  position: fixed; inset: 0 0 auto; z-index: 100;
  background: rgba(255,255,255,0);
  transition: background var(--t), border-color var(--t), box-shadow var(--t);
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: rgba(255,255,255,.82);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom-color: var(--line);
}
.nav-inner {
  max-width: var(--w); margin: 0 auto; padding: 0 28px;
  height: 60px; display: flex; align-items: center; gap: var(--sp-5);
}
.nav-logo { display: flex; align-items: baseline; gap: 9px; text-decoration: none; flex-shrink: 0; }
.nav-logo-text { font-size: 15px; font-weight: 700; color: var(--ink); letter-spacing: -0.01em; }
.nav-badge {
  font-size: 11px; font-weight: 700; color: var(--green-ink);
  border: 1px solid rgba(31,122,77,.35); padding: 1px 7px; border-radius: var(--r-pill);
}
.nav-links { display: flex; gap: 2px; margin-left: auto; }
.nav-links a {
  color: var(--ink-body); text-decoration: none; font-size: 14px; font-weight: 500;
  padding: 7px 14px; border-radius: var(--r-pill); transition: color var(--t), background var(--t);
}
.nav-links a:hover { color: var(--ink); background: rgba(0,0,0,.05); }
.nav-links a:active { transform: scale(.96); }
.nav-hamburger {
  display: none; background: none; border: none; color: var(--ink);
  cursor: pointer; margin-left: auto; padding: 11px;
}
.nav-hamburger svg { display: block; width: 22px; height: 22px; }
.nav-mobile {
  display: none; flex-direction: column;
  background: rgba(255,255,255,.96); border-top: 1px solid var(--line);
  backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
}
.nav-mobile.open { display: flex; }
.nav-mobile a { color: var(--ink-body); text-decoration: none; font-size: 15px; padding: 14px 28px; }
.nav-mobile a:hover { color: var(--green-ink); }
@media (max-width: 820px) {
  .nav-links { display: none; }
  .nav-hamburger { display: block; }
}

/* ── HERO ─────────────────────────────────── */
.hero { background: var(--paper); padding-top: 60px; }
.hero-inner {
  max-width: 920px; margin: 0 auto;
  padding: clamp(72px, 12vh, 140px) 28px clamp(48px, 8vh, 88px);
  text-align: center;
}
.hero-kicker {
  font-size: var(--fs-label); font-weight: 700; letter-spacing: .2em;
  text-transform: uppercase; color: var(--green-ink); margin-bottom: 22px;
}
.hero-title {
  font-size: var(--fs-display); font-weight: 700; line-height: 1.28;
  letter-spacing: -0.035em; color: var(--ink); margin-bottom: 22px;
}
.hero-title em {
  font-style: normal; color: #fff; background: var(--main);
  padding: 0 .14em; border-radius: 6px;
  -webkit-box-decoration-break: clone; box-decoration-break: clone;
}
.hero-slogan {
  font-size: var(--fs-lead); font-weight: 300; letter-spacing: -0.01em;
  color: var(--ink-muted); margin-bottom: 30px;
}
.hero-meta {
  display: inline-flex; flex-wrap: wrap; justify-content: center;
  align-items: center; gap: 10px 18px; margin-bottom: 36px;
  font-size: var(--fs-sub); color: var(--ink-body);
}
.hero-meta .dot { width: 4px; height: 4px; border-radius: 50%; background: var(--line-strong); }
.hero-meta b { font-weight: 600; color: var(--ink); }
.hero-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.hero-media {
  width: 100%;
  aspect-ratio: 7 / 2;
  min-height: 180px;
  max-height: 560px;
  overflow: hidden;
  background: var(--paper-2);
}
.hero-media img { width: 100%; height: 100%; object-fit: cover; object-position: center 52%; }

/* ── ABOUT ────────────────────────────────── */
.about-section { background: var(--canvas); }
.about-grid {
  display: grid; grid-template-columns: 1.15fr .85fr; gap: clamp(36px, 5vw, 72px);
  align-items: center;
}
.about-lead {
  font-size: var(--fs-h3); font-weight: 600; letter-spacing: -0.015em;
  color: var(--ink); line-height: 1.5; margin-bottom: 18px;
}
.about-body { font-size: var(--fs-body); color: var(--ink-body); line-height: 1.78; }
.about-facts { margin-top: 28px; display: flex; flex-direction: column; gap: 0; }
.fact {
  display: flex; gap: 16px; padding: 14px 0; border-top: 1px solid var(--line);
}
.fact:last-child { border-bottom: 1px solid var(--line); }
.fact-key {
  flex-shrink: 0; width: 56px; font-size: 13px; font-weight: 700;
  color: var(--green-ink); letter-spacing: .02em; padding-top: 2px;
}
.fact-val { font-size: var(--fs-sub); color: var(--ink); }
.about-poster {
  justify-self: center; width: 100%; max-width: 380px;
  aspect-ratio: 1654 / 2334; border-radius: var(--r-md); overflow: hidden;
  box-shadow: var(--shadow-photo);
}
.about-poster img { width: 100%; height: 100%; object-fit: cover; }

/* 통계 */
.stats {
  margin-top: var(--sp-8); padding-top: var(--sp-6);
  border-top: 1px solid var(--line);
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
}
.stat { text-align: center; }
.stat-num {
  font-size: clamp(34px, 4vw, 48px); font-weight: 700; color: var(--green-ink);
  line-height: 1; letter-spacing: -0.02em; font-variant-numeric: tabular-nums;
}
.stat-label { margin-top: 8px; font-size: 13px; color: var(--ink-muted); }
@media (max-width: 860px) {
  .about-grid { grid-template-columns: 1fr; }
  .about-poster { max-width: 320px; }
}
@media (max-width: 560px) { .stats { grid-template-columns: repeat(2, 1fr); gap: 28px 16px; } }

/* ── VIDEO BAND (다크) ────────────────────── */
.video-section { background: var(--dark); color: var(--on-dark); }
.video-wrap { max-width: 980px; margin: 0 auto; }
.video-embed {
  position: relative; width: 100%; aspect-ratio: 16/9;
  border-radius: var(--r-md); overflow: hidden; background: #000;
  box-shadow: var(--shadow-photo);
}
.video-embed iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.video-thumb {
  position: absolute; inset: 0; width: 100%; height: 100%;
  border: 0; padding: 0; cursor: pointer; background: #000; overflow: hidden;
}
.video-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s var(--ease); }
.video-thumb:hover img { transform: scale(1.03); }
.video-thumb-overlay {
  position: absolute; inset: 0; display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: 14px;
  background: linear-gradient(180deg, rgba(0,0,0,.15), rgba(0,0,0,.45));
}
.video-play {
  width: 72px; height: 72px; border-radius: 50%; background: rgba(255,255,255,.95);
  display: flex; align-items: center; justify-content: center;
  transition: transform .25s var(--ease), background var(--t);
}
.video-thumb:hover .video-play { transform: scale(1.08); background: #fff; }
.video-play svg { width: 26px; height: 26px; margin-left: 4px; fill: var(--green-deep); }
.video-cta { font-size: 14px; font-weight: 600; color: #fff; text-shadow: 0 1px 6px rgba(0,0,0,.5); letter-spacing: .02em; }

/* ── SPEAKERS ─────────────────────────────── */
.speakers-section { background: var(--paper); }
.spk-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(218px, 1fr)); gap: 20px;
}
.spk-card {
  background: var(--canvas); border: 1px solid var(--line); border-radius: var(--r-md);
  overflow: hidden; transition: border-color var(--t), transform var(--t);
}
.spk-card:hover { border-color: rgba(31,122,77,.45); }
.spk-photo { aspect-ratio: 4/3; background: var(--paper-2); overflow: hidden; }
.spk-photo img { width: 100%; height: 100%; object-fit: cover; object-position: center top; }
.spk-body { padding: 18px 18px 20px; }
.spk-tag {
  display: inline-block; font-size: 10.5px; font-weight: 700; letter-spacing: .08em;
  text-transform: uppercase; color: var(--green-ink); background: var(--green-soft);
  padding: 4px 9px; border-radius: var(--r-pill); margin-bottom: 11px;
}
.spk-name { font-size: 17px; font-weight: 700; color: var(--ink); letter-spacing: -0.01em; }
.spk-org { font-size: 13px; color: var(--ink-muted); margin-top: 2px; }
.spk-topic {
  font-size: 13.5px; color: var(--ink-body); line-height: 1.55;
  margin-top: 13px; padding-top: 13px; border-top: 1px solid var(--line);
}

/* ── PROGRAM (타임라인) ───────────────────── */
.program-section { background: var(--canvas); }
.timeline { max-width: 860px; margin: 0 auto; }
.tl-group {
  display: flex; align-items: center; gap: 12px;
  margin: 36px 0 6px; font-size: 14px; font-weight: 700; color: var(--green-ink);
}
.tl-group:first-child { margin-top: 0; }
.tl-group .tl-chair { font-weight: 400; color: var(--ink-muted); font-size: 13px; }
.tl-row {
  display: grid; grid-template-columns: 124px 1fr; gap: 20px;
  padding: 18px 0; border-top: 1px solid var(--line);
}
.tl-row:last-child { border-bottom: 1px solid var(--line); }
.tl-time { font-size: 14px; font-weight: 600; color: var(--green-ink); font-variant-numeric: tabular-nums; white-space: nowrap; }
.tl-time small { display: block; font-weight: 400; color: var(--ink-muted); font-size: 12px; margin-top: 2px; }
.tl-title { font-size: 16px; font-weight: 600; color: var(--ink); line-height: 1.4; }
.tl-row.muted .tl-title { font-weight: 400; color: var(--ink-muted); }
.tl-speaker { font-size: 14px; color: var(--ink-body); margin-top: 4px; }
.tl-speaker b { font-weight: 600; color: var(--ink); }
.tl-note { font-size: 13px; color: var(--ink-muted); margin-top: 5px; }
@media (max-width: 560px) {
  .tl-row { grid-template-columns: 1fr; gap: 6px; }
}

/* ── GALLERY ──────────────────────────────── */
.gallery-section { background: var(--paper); }
.gal-teaser {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px;
}
.gal-cell {
  aspect-ratio: 1; overflow: hidden; border-radius: var(--r-sm);
  cursor: zoom-in; background: var(--paper-2); position: relative;
}
.gal-cell img { width: 100%; height: 100%; object-fit: cover; transition: transform .4s var(--ease); }
.gal-cell:hover img { transform: scale(1.05); }
.gal-cell:active { transform: scale(.98); }
.gal-actions { display: flex; justify-content: center; margin-top: var(--sp-6); }
@media (max-width: 760px) { .gal-teaser { grid-template-columns: repeat(3, 1fr); gap: 6px; } }
@media (max-width: 460px) { .gal-teaser { grid-template-columns: repeat(2, 1fr); } }

/* 전체보기 오버레이 (아이폰 사진첩식 빽빽 그리드) */
.photos {
  position: fixed; inset: 0; z-index: 950;
  background: var(--canvas);
  display: flex; flex-direction: column;
  opacity: 0; visibility: hidden; transform: translateY(8px);
  transition: opacity .28s var(--ease), transform .28s var(--ease), visibility .28s var(--ease);
}
.photos.open { opacity: 1; visibility: visible; transform: none; }
.photos-bar {
  flex-shrink: 0; display: flex; align-items: center; justify-content: space-between;
  gap: 16px; padding: 14px 20px;
  border-bottom: 1px solid var(--line);
  background: rgba(255,255,255,.85); backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
}
.photos-title { font-size: 17px; font-weight: 700; color: var(--ink); }
.photos-title span { color: var(--ink-muted); font-weight: 400; margin-left: 8px; font-size: 14px; }
.photos-close {
  width: 38px; height: 38px; border-radius: 50%; border: none; cursor: pointer;
  background: var(--paper-2); color: var(--ink);
  display: flex; align-items: center; justify-content: center; transition: background var(--t);
}
.photos-close:hover { background: var(--line); }
.photos-close:active { transform: scale(.95); }
.photos-close svg { width: 15px; height: 15px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; }
.photos-grid {
  flex: 1; overflow-y: auto; -webkit-overflow-scrolling: touch;
  display: grid; grid-template-columns: repeat(auto-fill, minmax(108px, 1fr));
  gap: 3px; padding: 3px; align-content: start;
}
.ph-cell { aspect-ratio: 1; overflow: hidden; cursor: zoom-in; background: var(--paper-2); }
.ph-cell img { width: 100%; height: 100%; object-fit: cover; transition: opacity .2s; }
.ph-cell:hover img { opacity: .85; }
.ph-cell:active { transform: scale(.97); }
@media (max-width: 760px) { .photos-grid { grid-template-columns: repeat(auto-fill, minmax(88px, 1fr)); gap: 2px; padding: 2px; } }
@media (max-width: 460px) { .photos-grid { grid-template-columns: repeat(4, 1fr); } }

/* ── LIGHTBOX ─────────────────────────────── */
.lightbox {
  position: fixed; inset: 0; z-index: 1000; background: rgba(10,12,11,.96);
  display: none; align-items: center; justify-content: center;
}
.lightbox.open { display: flex; }
.lightbox img { max-width: 90vw; max-height: 88vh; object-fit: contain; border-radius: var(--r-sm); }
.lb-btn {
  position: absolute; border: 1px solid rgba(255,255,255,.2); background: rgba(255,255,255,.1);
  color: #fff; border-radius: 50%; cursor: pointer;
  display: flex; align-items: center; justify-content: center; transition: background var(--t);
}
.lb-btn:hover { background: rgba(255,255,255,.22); }
.lb-btn svg { fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.lb-close { top: 20px; right: 20px; width: 44px; height: 44px; }
.lb-close svg { width: 16px; height: 16px; }
.lb-nav { top: 50%; transform: translateY(-50%); width: 50px; height: 50px; }
.lb-nav:active { transform: translateY(-50%) scale(.95); }
.lb-prev { left: 20px; } .lb-next { right: 20px; }
.lb-nav svg { width: 24px; height: 24px; }
.lb-count {
  position: absolute; bottom: 22px; left: 50%; transform: translateX(-50%);
  color: rgba(255,255,255,.85); font-size: 13px; font-variant-numeric: tabular-nums;
  background: rgba(0,0,0,.4); padding: 5px 12px; border-radius: var(--r-pill);
}
@media (max-width: 540px) {
  .lb-nav { width: 42px; height: 42px; } .lb-prev { left: 8px; } .lb-next { right: 8px; }
}

/* ── SPONSORS ─────────────────────────────── */
.sponsors-section { background: var(--canvas); }
.tier { margin-bottom: var(--sp-7); }
.tier:last-child { margin-bottom: 0; }
.tier-label {
  text-align: center; font-size: var(--fs-label); font-weight: 700;
  letter-spacing: .14em; text-transform: uppercase; color: var(--ink-muted);
  margin-bottom: 22px; position: relative;
}
.tier-label::before, .tier-label::after {
  content: ''; position: absolute; top: 50%; width: 56px; height: 1px; background: var(--line);
}
.tier-label::before { right: calc(50% + 60px); }
.tier-label::after { left: calc(50% + 60px); }
.logos { display: flex; flex-wrap: wrap; justify-content: center; gap: 16px; }
.logo {
  background: var(--canvas); border: 1px solid var(--line); border-radius: var(--r-md);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 8px; padding: 24px; transition: border-color var(--t);
}
.logo:hover { border-color: var(--green); }
.logo.lg { width: 240px; height: 124px; }
.logo.md { width: 188px; height: 104px; }
.logo img { max-width: 80%; max-height: 52px; object-fit: contain; }
.logo-ph { font-size: 14px; font-weight: 700; color: var(--ink); text-align: center; }
.logo-sub { font-size: 12px; color: var(--ink-muted); }

/* ── FOOTER ───────────────────────────────── */
.footer { background: var(--dark); color: var(--on-dark); padding: 56px 0 32px; }
.footer-inner {
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 18px; padding-bottom: 28px;
  border-bottom: 1px solid rgba(255,255,255,.1); margin-bottom: 24px;
}
.footer-title { font-size: 16px; font-weight: 700; color: var(--on-dark); }
.footer-org { font-size: 13px; color: var(--on-dark-muted); margin-top: 5px; }
.footer-nav { display: flex; gap: 20px; }
.footer-nav a { color: var(--on-dark-muted); text-decoration: none; font-size: 14px; transition: color var(--t); }
.footer-nav a:hover { color: var(--on-dark); }
.footer-copy { text-align: center; font-size: 12.5px; color: var(--on-dark-muted); }

/* ── REDUCED MOTION ───────────────────────── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important; animation-iteration-count: 1 !important;
    transition-duration: .001ms !important; scroll-behavior: auto !important;
  }
}

@media (max-width: 768px) { .section { padding: var(--sp-8) 0; } }