:root {
  color-scheme: light dark;
  --accent: #059669;
  --btn-bg: #059669;
  --btn-hover: #047857;
  --accent-light: #ecfdf5;
  --accent-light-hover: #d1fae5;
  --text: #1f2937;
  --muted: #5b6472;
  --bg: #f9fafb;
  --card: #ffffff;
  --border: #e5e7eb;
  --success: #15803d;
  --danger: #dc2626;
}
@media (prefers-color-scheme: dark) {
  :root {
    --accent: #34d399;
    --btn-bg: #059669;
    --btn-hover: #10b981;
    --accent-light: #0f2e26;
    --accent-light-hover: #14463a;
    --text: #e7eaf0;
    --muted: #a3acba;
    --bg: #111827;
    --card: #1f2937;
    --border: #374151;
    --success: #4ade80;
    --danger: #f87171;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", Pretendard, "Noto Sans KR", "Malgun Gothic", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible, button:focus-visible, input:focus-visible,
select:focus-visible, [tabindex]:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--card);
  color: var(--accent);
  padding: 8px 16px;
  z-index: 10;
  border-radius: 0 0 8px 0;
  font-weight: 600;
}
.skip-link:focus { left: 0; }

header.site-header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  max-width: 860px;
  margin: 0 auto;
  padding: 12px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}
.logo {
  font-size: 19px;
  font-weight: 700;
  color: var(--text);
}
.logo:hover { text-decoration: none; }
.logo span { color: var(--accent); }
nav.main-nav { display: flex; gap: 4px 14px; flex-wrap: wrap; }
nav.main-nav a {
  font-size: 14px;
  color: var(--muted);
  padding: 4px 2px;
}
nav.main-nav a:hover, nav.main-nav a.active { color: var(--accent); }
nav.main-nav a.active { font-weight: 600; }

main {
  max-width: 860px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}
h1 { font-size: 26px; line-height: 1.4; margin: 8px 0 4px; }
h2 { font-size: 20px; margin: 36px 0 8px; }
h3 { font-size: 17px; margin: 24px 0 6px; }
p.lead { color: var(--muted); margin-top: 0; }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  margin: 16px 0;
}

.dropzone {
  border: 2px dashed var(--accent);
  border-radius: 12px;
  background: var(--accent-light);
  padding: 36px 16px;
  text-align: center;
  cursor: pointer;
  transition: background 0.15s;
}
.dropzone:hover, .dropzone.dragover { background: var(--accent-light-hover); }
.dropzone strong { display: block; font-size: 17px; margin-bottom: 4px; }
.dropzone small { color: var(--muted); font-size: 14px; }

.controls { display: flex; flex-wrap: wrap; gap: 16px; margin-top: 16px; }
.control-group { flex: 1 1 220px; }
.control-group label.group-label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.control-group .hint { font-size: 13px; color: var(--muted); margin-top: 4px; }
input[type="range"] { width: 100%; accent-color: var(--accent); }
select, input[type="number"], input[type="text"], textarea {
  width: 100%;
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 15px;
  background: var(--card);
  color: var(--text);
}
.radio-row { display: flex; gap: 12px; flex-wrap: wrap; }
.radio-row label { font-size: 15px; display: flex; align-items: center; gap: 4px; }
input[type="radio"], input[type="checkbox"] { accent-color: var(--accent); width: 18px; height: 18px; }

button.primary {
  background: var(--btn-bg);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 12px 24px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  margin-top: 16px;
  min-height: 44px;
}
button.primary:hover { background: var(--btn-hover); }
button.primary:disabled { background: #9ca3af; cursor: not-allowed; }
button.secondary {
  background: var(--card);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 16px;
  font-size: 15px;
  cursor: pointer;
  min-height: 44px;
}
button.secondary:hover { border-color: var(--accent); color: var(--accent); }
a.dl-btn, button.dl-btn {
  display: inline-block;
  background: #15803d;
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 10px 16px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  min-height: 40px;
}
a.dl-btn:hover, button.dl-btn:hover { text-decoration: none; opacity: 0.9; }

.result-row {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.result-row:last-child { border-bottom: none; }
.result-row img.thumb {
  width: 64px;
  height: 64px;
  object-fit: cover;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--card);
}
.result-info { flex: 1 1 200px; font-size: 14px; }
.result-info .fname { font-weight: 600; word-break: break-all; }
.result-info .sizes { color: var(--muted); }
.result-info .saved { color: var(--success); font-weight: 600; }
.status { font-size: 14px; color: var(--muted); margin-top: 12px; }
.error-msg { color: var(--danger); font-size: 14px; margin-top: 8px; }

.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin: 24px 0;
}
.tool-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  display: block;
  color: var(--text);
}
.tool-card:hover { border-color: var(--accent); text-decoration: none; }
.tool-card h3 { margin: 0 0 6px; color: var(--accent); }
.tool-card p { margin: 0; font-size: 14px; color: var(--muted); }

ol.steps { padding-left: 20px; }
ol.steps li { margin-bottom: 6px; }
.faq-item { margin-bottom: 18px; }
.faq-item h3 { margin: 0 0 4px; font-size: 16px; }
.faq-item p { margin: 0; color: var(--muted); font-size: 15px; }

table.spec {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  margin: 12px 0;
}
table.spec th, table.spec td {
  border: 1px solid var(--border);
  padding: 8px 10px;
  text-align: left;
}
table.spec th { background: var(--bg); }

#stage {
  max-width: 100%;
  touch-action: none;
  border-radius: 8px;
  display: block;
  margin: 16px auto 0;
}
canvas.preview {
  max-width: 100%;
  border: 1px solid var(--border);
  border-radius: 8px;
  display: block;
  margin: 16px auto 0;
  background: var(--card);
}

footer.site-footer {
  border-top: 1px solid var(--border);
  background: var(--card);
  margin-top: 40px;
}
.footer-inner {
  max-width: 860px;
  margin: 0 auto;
  padding: 20px 16px;
  font-size: 13px;
  color: var(--muted);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}
.footer-inner a { color: var(--muted); margin-right: 12px; }

@media (max-width: 600px) {
  h1 { font-size: 22px; }
  .dropzone { padding: 28px 12px; }
  nav.main-nav { gap: 2px 12px; }
}

/* 가이드 그리드 */
.guide-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 12px;
  margin: 1rem 0 2rem;
}
.guide-card {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px 16px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  text-decoration: none;
  color: var(--text);
  transition: border-color .15s, box-shadow .15s;
}
.guide-card:hover {
  border-color: var(--accent);
  box-shadow: 0 2px 8px rgba(37,99,235,.10);
}
.guide-card strong {
  font-size: .95rem;
  color: var(--accent);
  line-height: 1.4;
}
.guide-card span {
  font-size: .82rem;
  color: var(--muted);
  line-height: 1.4;
}

/* ===== 계산기 전용 스타일 ===== */
.calc-form { display: grid; gap: 16px; }
.field { display: flex; flex-direction: column; gap: 6px; }
.field label { font-weight: 600; font-size: .95rem; }
.field .sub { font-weight: 400; color: var(--muted); font-size: .85rem; }
.field input[type=number], .field input[type=text], .field input[type=date], .field select {
  width: 100%; padding: 12px 14px; font-size: 1.05rem;
  border: 1px solid var(--border); border-radius: 10px;
  background: var(--card); color: var(--text); min-height: 48px;
}
.field input:focus, .field select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.radio-pills { display: flex; flex-wrap: wrap; gap: 8px; }
.radio-pills label {
  padding: 9px 14px; border: 1px solid var(--border); border-radius: 999px;
  cursor: pointer; font-size: .92rem; user-select: none;
}
.radio-pills input { position: absolute; opacity: 0; }
.radio-pills input:checked + span { color: #fff; }
.radio-pills label:has(input:checked) { background: var(--accent); border-color: var(--accent); }
.calc-btn {
  width: 100%; padding: 14px; font-size: 1.1rem; font-weight: 700;
  background: var(--btn-bg); color: #fff; border: none; border-radius: 10px;
  cursor: pointer; min-height: 52px; margin-top: 4px;
}
.calc-btn:hover { background: var(--btn-hover); }
.result-box {
  margin-top: 20px; padding: 20px; border-radius: 12px;
  background: var(--accent-light); border: 1px solid var(--border);
}
.result-main { font-size: 1.05rem; color: var(--muted); margin: 0 0 4px; }
.result-big { font-size: 2rem; font-weight: 800; color: var(--accent); margin: 0; line-height: 1.2; }
.result-sub { font-size: .95rem; color: var(--muted); margin: 8px 0 0; }
.breakdown { width: 100%; margin-top: 16px; border-collapse: collapse; font-size: .95rem; }
.breakdown th, .breakdown td { padding: 9px 4px; text-align: left; border-bottom: 1px solid var(--border); }
.breakdown td:last-child, .breakdown th:last-child { text-align: right; }
.breakdown tr.total td { font-weight: 700; border-top: 2px solid var(--border); border-bottom: none; }
.note-box {
  margin-top: 16px; padding: 12px 16px; font-size: .88rem; color: var(--muted);
  background: var(--bg); border-radius: 8px; line-height: 1.6;
}
@media (max-width: 480px) {
  .field-row { grid-template-columns: 1fr; }
  .result-big { font-size: 1.6rem; }
}