/* ============================================================
   AVIATOR — 비행기 덕후를 위한 사이트
   공용 디자인 시스템
   ============================================================ */

:root {
  /* 색상 — 콕핏/밤하늘 테마 */
  --bg:        #0a0f1c;
  --bg-2:      #0e1626;
  --panel:     #131d31;
  --panel-2:   #18243c;
  --line:      #23324f;
  --text:      #e8eefb;
  --muted:     #8fa1c4;
  --dim:       #5f6f8f;

  --accent:    #4da3ff;   /* 하늘색 */
  --accent-2:  #21d4a8;   /* HUD 그린 */
  --on-accent: #06121f;   /* 강조색 배경 위의 진한 글자 */
  --warn:      #ffb347;
  --danger:    #ff5d6c;

  --radius:    16px;
  --radius-sm: 10px;
  --shadow:    0 10px 40px rgba(0,0,0,.45);
  --maxw:      1180px;

  --font: "Segoe UI", -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo",
          "Malgun Gothic", Roboto, sans-serif;
  --mono: "SFMono-Regular", "Cascadia Code", Consolas, "Courier New", monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background:
    radial-gradient(1200px 700px at 80% -10%, rgba(77,163,255,.10), transparent 60%),
    radial-gradient(900px 600px at 0% 20%, rgba(33,212,168,.06), transparent 55%),
    /* 평평한 세계 — 방위도법 동심원(돔 지평선) 모티프, 전 페이지 공통 */
    repeating-radial-gradient(circle at 50% 126%, transparent 0 78px, rgba(120,220,190,.045) 78px 80px),
    var(--bg);
  background-attachment: fixed;
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

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

h1, h2, h3 { line-height: 1.2; margin: 0 0 .5em; letter-spacing: -.01em; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ---------- 네비게이션 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(10,15,28,.78);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 12px 20px;
  display: flex; align-items: center; gap: 22px;
}
.brand {
  display: flex; align-items: center; gap: 10px;
  font-weight: 800; font-size: 1.15rem; color: var(--text);
  letter-spacing: .02em;
}
.brand:hover { text-decoration: none; }
.brand .logo {
  width: 34px; height: 34px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  border-radius: 10px; font-size: 18px;
  box-shadow: 0 6px 18px rgba(77,163,255,.35);
}
.nav-links { display: flex; gap: 4px; margin-left: auto; flex-wrap: wrap; }
.nav-right { display: flex; align-items: center; gap: 10px; }

/* 그룹 드롭다운 네비 (Play / Explore) */
.nav-group { position: relative; }
.nav-grp-btn { background: none; border: 0; color: var(--muted); font: inherit; font-weight: 600;
  font-size: .92rem; padding: 8px 14px; border-radius: 999px; cursor: pointer; display: flex; align-items: center; gap: 5px; }
.nav-grp-btn:hover { color: var(--text); background: var(--panel); }
.nav-group.has-active .nav-grp-btn { color: var(--accent); }
.caret { font-size: .7em; opacity: .7; }
.nav-menu { position: absolute; top: 100%; left: 0; margin-top: 6px; background: var(--panel);
  border: 1px solid var(--line); border-radius: 12px; padding: 6px; min-width: 172px; display: none;
  flex-direction: column; gap: 2px; box-shadow: var(--shadow); z-index: 60; }
.nav-group.open .nav-menu { display: flex; }
.nav-menu a { color: var(--muted); padding: 8px 12px; border-radius: 8px; font-size: .9rem; font-weight: 600; }
.nav-menu a:hover { color: var(--text); background: var(--panel-2); text-decoration: none; }
.nav-menu a.active { color: var(--on-accent); background: var(--accent); }
@media (max-width: 760px) {
  .nav-grp-btn { width: 100%; justify-content: space-between; }
  .nav-menu { position: static; display: flex; margin: 2px 0 8px; box-shadow: none;
    border: 0; background: transparent; padding: 0 0 0 14px; min-width: 0; }
}
.nav-links a {
  color: var(--muted); padding: 8px 14px; border-radius: 999px;
  font-size: .92rem; font-weight: 600; transition: .15s;
}
.nav-links a:hover { color: var(--text); background: var(--panel); text-decoration: none; }
.nav-links a.active { color: var(--on-accent); background: var(--accent); }

.nav-toggle { display: none; background: none; border: 0; color: var(--text);
  font-size: 1.5rem; cursor: pointer; }

.lang-btn {
  background: var(--panel); border: 1px solid var(--line); color: var(--muted);
  padding: 7px 13px; border-radius: 999px; font-weight: 700; font-size: .82rem;
  cursor: pointer; transition: .15s; white-space: nowrap; flex-shrink: 0;
}
.lang-btn:hover { color: var(--text); border-color: var(--accent); }

@media (max-width: 760px) {
  .nav-toggle { display: block; }
  .nav-links {
    display: none; width: 100%; flex-direction: column; margin: 10px 0 4px;
  }
  .nav-links.open { display: flex; }
  .nav-links a { text-align: center; }
}

/* ---------- 버튼 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 11px 20px; border-radius: 999px; border: 1px solid transparent;
  font-weight: 700; font-size: .95rem; cursor: pointer; transition: .15s;
  background: var(--accent); color: var(--on-accent);
}
.btn:hover { filter: brightness(1.08); text-decoration: none; transform: translateY(-1px); }
.btn.ghost { background: transparent; border-color: var(--line); color: var(--text); }
.btn.ghost:hover { border-color: var(--accent); background: var(--panel); }
.btn.sm { padding: 7px 14px; font-size: .85rem; }

/* ---------- 카드/패널 ---------- */
.panel {
  background: linear-gradient(180deg, var(--panel), var(--panel-2));
  border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.section { padding: 60px 0; }
.section-head { text-align: center; max-width: 620px; margin: 0 auto 36px; }
.section-head .eyebrow {
  color: var(--accent-2); font-weight: 800; font-size: .8rem;
  letter-spacing: .18em; text-transform: uppercase;
}
.section-head h2 { font-size: clamp(1.6rem, 3.5vw, 2.3rem); margin-top: 8px; }
.section-head p { color: var(--muted); }

/* ---------- 배지/칩 ---------- */
.badge {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 3px 10px; border-radius: 999px; font-size: .72rem; font-weight: 700;
  background: var(--panel); border: 1px solid var(--line); color: var(--muted);
}
.badge.dot::before { content:""; width:7px; height:7px; border-radius:50%;
  background: var(--accent-2); box-shadow: 0 0 8px var(--accent-2); }

.tag {
  padding: 4px 11px; border-radius: 8px; font-size: .78rem; font-weight: 600;
  background: rgba(77,163,255,.12); color: var(--accent); border: 1px solid rgba(77,163,255,.25);
}

/* ---------- 폼 ---------- */
input, select, textarea {
  font-family: inherit; font-size: .95rem;
  background: var(--bg-2); color: var(--text);
  border: 1px solid var(--line); border-radius: var(--radius-sm);
  padding: 11px 14px; outline: none; transition: .15s;
}
input:focus, select:focus, textarea:focus { border-color: var(--accent); }
input::placeholder { color: var(--dim); }
label { font-size: .85rem; color: var(--muted); font-weight: 600; }

/* ---------- 푸터 ---------- */
.footer {
  border-top: 1px solid var(--line); margin-top: 40px;
  padding: 30px 0; color: var(--dim); font-size: .88rem;
}
.footer .container { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }

/* ---------- 유틸 ---------- */
.grid { display: grid; gap: 20px; }
.muted { color: var(--muted); }
.center { text-align: center; }
.hidden { display: none !important; }
.mono { font-family: var(--mono); }

/* 활주로 애니메이션 로딩바 */
.loading { display: inline-block; color: var(--muted); }
.loading::after { content: "···"; animation: dots 1.2s steps(4) infinite; }
@keyframes dots { 0%{content:""} 25%{content:"·"} 50%{content:"··"} 75%{content:"···"} }

/* ---------- 접근성: 키보드 포커스 + 모션 축소 ---------- */
a:focus-visible, button:focus-visible, input:focus-visible,
select:focus-visible, textarea:focus-visible, .chip:focus-visible,
.mode:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

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

/* ---------- 여행 제휴 CTA (Door B — docs/TRAVEL.md; 게임과 분리) ---------- */
.aff-block { margin-top: 16px; padding: 14px; border: 1px solid var(--line); border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--panel), var(--panel-2)); }
.aff-head { font-weight: 700; margin-bottom: 10px; color: var(--text); }
.aff-btns { display: flex; flex-wrap: wrap; gap: 8px; }
.aff-btn { display: inline-block; padding: 8px 14px; border-radius: 999px; border: 1px solid var(--line);
  background: var(--panel-2); color: var(--text); text-decoration: none; font-size: .88rem; font-weight: 600;
  min-height: 44px; line-height: 28px; transition: .15s; }
.aff-btn:hover { border-color: var(--accent); color: var(--accent); }
.aff-ftc { margin-top: 10px; font-size: .72rem; color: var(--dim); }