/* 학생 화면(목록·뷰어) 전용. theme.css는 웹 폰트를 @import 해서 첫 화면이
   늦게 뜰 수 있어, 학생 화면은 시스템 글꼴과 이 파일 하나로만 그린다.
   색은 theme.css(사이트 공통 디자인)의 값과 맞춘다. */

:root {
  --bg: #f4f5fa;
  --card: #ffffff;
  --text: #1a1c22;
  --sub: #5b606b;
  --line: rgba(0, 0, 0, 0.08);
  --accent: #0071e3;
  --accent-light: rgba(0, 113, 227, 0.12);
  --warn: #c2410c;
  --warn-light: rgba(234, 88, 12, 0.12);
  --notice: #fff7e6;
  --font: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Malgun Gothic", "Pretendard", system-ui, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d0e13;
    --card: #1c1d24;
    --text: #f2f4f8;
    --sub: #aab0bd;
    --line: rgba(255, 255, 255, 0.1);
    --accent: #0a84ff;
    --accent-light: rgba(10, 132, 255, 0.18);
    --warn: #fb923c;
    --warn-light: rgba(251, 146, 60, 0.16);
    --notice: #2a2214;
  }
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body { font-family: var(--font); background: var(--bg); color: var(--text); min-height: 100vh; }
a { color: var(--accent); }
[hidden] { display: none !important; }

/* ---------- 상단 바 ---------- */
.bar {
  display: flex; align-items: center; gap: 12px;
  height: 52px; padding: 0 16px;
  background: var(--card); border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 8px; text-decoration: none; color: var(--text); font-weight: 800; white-space: nowrap; flex-shrink: 0; }
.brand img { display: block; }
.bar-title {
  flex: 1; min-width: 0; margin: 0; font-size: 15px; font-weight: 600; color: var(--sub);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.bar-actions { display: flex; gap: 6px; flex-shrink: 0; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  height: 34px; padding: 0 12px; border-radius: 999px;
  border: 1px solid var(--line); background: var(--card); color: var(--text);
  font: inherit; font-size: 13px; font-weight: 600; text-decoration: none; cursor: pointer; white-space: nowrap;
}
.btn:hover { background: var(--accent-light); color: var(--accent); }
.btn.primary { background: var(--accent); border-color: transparent; color: #fff; }
.btn.warn { color: var(--warn); background: var(--warn-light); border-color: transparent; }
.btn.ghost { border-color: transparent; background: transparent; }

/* ---------- 목록 ---------- */
.list { max-width: 720px; margin: 0 auto; padding: 28px 16px 60px; }
.list h1 { font-size: 22px; margin: 0 0 18px; }
.items { display: flex; flex-direction: column; gap: 10px; }
.item {
  display: flex; flex-direction: column; gap: 2px;
  padding: 16px 18px; border-radius: 14px;
  background: var(--card); border: 1px solid var(--line);
  text-decoration: none; color: var(--text);
}
.item:hover { border-color: var(--accent); }
.item-title { font-weight: 700; font-size: 16px; }
.item-path { font-size: 13px; color: var(--sub); }
.empty { color: var(--sub); line-height: 1.7; }

/* ---------- 뷰어 ---------- */
body.viewer { display: flex; flex-direction: column; height: 100vh; height: 100dvh; overflow: hidden; }
.frame-wrap { position: relative; flex: 1; min-height: 0; }
.frame-wrap iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; background: #fff; }
.loading {
  position: absolute; inset: 0; z-index: 1; pointer-events: none;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 12px;
  color: var(--sub); font-size: 14px; background: var(--bg);
}
.spinner {
  width: 32px; height: 32px; border-radius: 50%;
  border: 3px solid var(--line); border-top-color: var(--accent);
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.notice {
  display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  padding: 10px 16px; background: var(--notice); border-bottom: 1px solid var(--line);
  font-size: 14px; font-weight: 600;
}
.notice-actions { display: flex; gap: 6px; flex-wrap: wrap; }

@media (max-width: 560px) {
  .brand span { display: none; }
  .bar { gap: 8px; padding: 0 10px; }
  .btn { padding: 0 10px; }
}