/* 디지털 수업 데이터 체크인 — 공통 스타일 (디자인 토큰) */
:root {
  color-scheme: light;
  --paper: #fffdf7;          /* 크림 종이 */
  --paper-2: #f6f1e3;        /* 종이 그늘 */
  --grid: rgba(26, 158, 135, 0.13);
  --card: #ffffff;
  --ink: #1f2a2e;
  --ink-2: #4b5a60;
  --ink-3: #8a979c;
  --line: #d9d3c2;
  --mint: #1a9e87;
  --mint-soft: #d7f2eb;
  --coral: #e8604f;
  --coral-soft: #fde3de;
  --sun: #f2b705;
  --sun-soft: #fff1c2;
  --sky: #2a78d6;
  --sky-soft: #dbe9fb;
  --ok: #0ca30c;
  --warn: #d03b3b;
  /* 차트 범주색 (validate_palette.js 통과: light) */
  --s1: #1a9e87; --s2: #e8604f; --s3: #2a78d6; --s4: #e3a300; --s5: #e87ba4; --s6: #6250d6;
  --chart-grid: #e8e3d4;
  --chart-axis: #c3bda9;
  --radius-lg: 22px;
  --radius: 14px;
  --radius-sm: 9px;
  --font-display: "Jua", "Noto Sans KR", sans-serif;
  --font-body: "Noto Sans KR", system-ui, -apple-system, "Segoe UI", sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --paper: #171b1a;
    --paper-2: #1f2423;
    --grid: rgba(26, 158, 135, 0.12);
    --card: #22282a;
    --ink: #f0efe8;
    --ink-2: #c3c6bd;
    --ink-3: #8a9094;
    --line: #3a4244;
    --mint-soft: #1c3a35;
    --coral-soft: #44282a;
    --sun-soft: #3f3618;
    --sky-soft: #1e3147;
    --s1: #1a9e87; --s2: #e8604f; --s3: #3987e5; --s4: #c98500; --s5: #d55181; --s6: #9085e9;
    --chart-grid: #2c3233;
    --chart-axis: #3f4749;
  }
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #171b1a;
  --paper-2: #1f2423;
  --grid: rgba(26, 158, 135, 0.12);
  --card: #22282a;
  --ink: #f0efe8;
  --ink-2: #c3c6bd;
  --ink-3: #8a9094;
  --line: #3a4244;
  --mint-soft: #1c3a35;
  --coral-soft: #44282a;
  --sun-soft: #3f3618;
  --sky-soft: #1e3147;
  --s1: #1a9e87; --s2: #e8604f; --s3: #3987e5; --s4: #c98500; --s5: #d55181; --s6: #9085e9;
  --chart-grid: #2c3233;
  --chart-axis: #3f4749;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 24px 24px;
  line-height: 1.5;
  overflow-x: hidden;
}
h1, h2, h3, .display { font-family: var(--font-display); font-weight: 400; letter-spacing: -0.01em; }
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
a { color: var(--mint); }
:focus-visible { outline: 3px solid var(--sky); outline-offset: 2px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* 상단 미리보기 띠 */
.demo-banner {
  display: none;
  background: var(--sun);
  color: #1f2a2e;
  font-size: 13px;
  text-align: center;
  padding: 6px 12px;
  font-weight: 500;
}
body.demo .demo-banner { display: block; }

/* 두툼한 버튼 — 종이 위 스티커 느낌 (그림자 대신 오프셋 밑판) */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 48px; padding: 10px 20px;
  border: 2px solid var(--ink); border-radius: var(--radius);
  background: var(--card); color: var(--ink);
  font-weight: 600; font-size: 16px;
  box-shadow: 0 3px 0 var(--ink);
  transition: transform .08s ease, box-shadow .08s ease, background .15s;
  word-break: keep-all;
  text-decoration: none;
}
.btn:active { transform: translateY(3px); box-shadow: 0 0 0 var(--ink); }
.btn.primary { background: var(--mint); color: #fff; }
.btn.coral { background: var(--coral); color: #fff; }
.btn.sun { background: var(--sun); color: #1f2a2e; }
.btn.ghost { border-color: var(--line); box-shadow: 0 3px 0 var(--line); background: transparent; }
.btn[disabled] { opacity: .45; cursor: not-allowed; }
.btn.block { width: 100%; }
.btn.small { min-height: 38px; padding: 6px 14px; font-size: 14px; border-radius: var(--radius-sm); }

.card {
  background: var(--card);
  border: 2px solid var(--ink);
  border-radius: var(--radius-lg);
  box-shadow: 0 4px 0 var(--ink);
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
}