/* =========================
   RSS Color Theme (Full)
   - Orange (RSS) + Warm Amber
   - Keep SunStripe dark UI vibe
========================= */

:root{
  /* Base */
  --bg:#0b1220;
  --card:#101a30;
  --card2:#0c1428;
  --text:#fff7ed;      /* warm white */
  --muted:#f6caa3;     /* peach-muted */

  /* RSS Colors */
  --primary:#fb923c;   /* RSS orange */
  --accent:#f97316;    /* deep orange */
  --good:#22c55e;
  --bad:#ef4444;

  --border:rgba(251,146,60,.22);

  --radius:16px;
  --shadow:0 18px 44px rgba(0,0,0,.38);

  /* Extra tokens */
  --glow: rgba(249,115,22,.28);
  --glow2: rgba(251,146,60,.18);
  --ring: rgba(251,146,60,.55);

  --codeText:#ffd7b0;
  --codeBg: rgba(0,0,0,.28);
  --chipBg: rgba(255,255,255,.06);
}

/* Reset */
*{ box-sizing:border-box; }
html,body{ height:100%; }

body{
  margin:0;
  font-family: "Noto Sans JP", system-ui, -apple-system, Segoe UI, sans-serif;
  background:
    radial-gradient(900px 520px at 20% 10%, rgba(251,146,60,.24), transparent 60%),
    radial-gradient(900px 520px at 80% 0%, rgba(249,115,22,.22), transparent 60%),
    radial-gradient(820px 520px at 50% 110%, rgba(255,214,165,.08), transparent 55%),
    var(--bg);
  color:var(--text);
  line-height:1.7;
}

/* Layout */
.wrap{ max-width:1100px; margin:0 auto; padding:18px; }

.top{
  position:sticky; top:0; z-index:10;
  backdrop-filter: blur(10px);
  background: rgba(11, 18, 32, .72);
  border-bottom:1px solid var(--border);
  box-shadow: 0 10px 24px rgba(0,0,0,.25);
}

.brand{ display:flex; align-items:center; gap:14px; padding:12px 0; }
.logo{
  width:44px; height:44px; border-radius:14px;
  display:grid; place-items:center;
  background:
    radial-gradient(18px 18px at 30% 30%, rgba(255,255,255,.25), transparent 55%),
    linear-gradient(135deg, rgba(251,146,60,.55), rgba(249,115,22,.30));
  border:1px solid rgba(255,255,255,.10);
  box-shadow: 0 18px 44px rgba(0,0,0,.35), 0 0 0 6px rgba(249,115,22,.08);
  font-weight:900;
  letter-spacing:.06em;
}

.brandText .title{ font-size:18px; font-weight:900; }
.brandText .sub{ font-size:12px; color:rgba(255,214,165,.78); margin-top:2px; }

.headerActions{
  display:flex; gap:10px; flex-wrap:wrap;
  margin: 0 0 12px 0;
}

.main{ padding-top:16px; padding-bottom:30px; }

/* Card */
.card{
  background:
    radial-gradient(520px 220px at 15% 0%, rgba(251,146,60,.10), transparent 60%),
    radial-gradient(520px 220px at 85% 0%, rgba(249,115,22,.10), transparent 60%),
    linear-gradient(180deg, rgba(18,27,54,.94), rgba(10,18,40,.92));
  border:1px solid rgba(251,146,60,.18);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding:16px;
  margin: 14px 0;
}

h2{ margin:0 0 10px 0; font-size:18px; letter-spacing:.02em; }
h3{ margin:14px 0 10px 0; font-size:15px; letter-spacing:.02em; }

.muted{ color: rgba(255,214,165,.76); }
.small{ font-size:12px; }

/* Grid */
.grid2{
  display:grid;
  grid-template-columns: 1fr;
  gap:14px;
}
@media (min-width: 960px){
  .grid2{ grid-template-columns: 1fr 1fr; }
}

/* Buttons */
.btn{
  display:inline-flex; align-items:center; justify-content:center;
  gap:8px;
  padding:10px 12px;
  border-radius: 12px;
  border:1px solid rgba(255,255,255,.12);
  background:
    radial-gradient(18px 18px at 25% 30%, rgba(255,255,255,.18), transparent 55%),
    linear-gradient(180deg, rgba(251,146,60,.24), rgba(249,115,22,.14));
  color: var(--text);
  text-decoration:none;
  cursor:pointer;
  user-select:none;
  font-weight:900;
  transition: transform .12s ease, filter .12s ease, box-shadow .12s ease, border-color .12s ease;
}
.btn:hover{
  filter: brightness(1.06);
  transform: translateY(-1px);
  box-shadow: 0 14px 26px rgba(0,0,0,.25), 0 0 0 6px rgba(249,115,22,.08);
  border-color: rgba(251,146,60,.35);
}
.btn:active{
  transform: translateY(0px);
  filter: brightness(1.02);
}

.btn.ghost{
  background: rgba(255,255,255,.06);
  border-color: rgba(255,255,255,.12);
}
.btn.ghost:hover{
  border-color: rgba(251,146,60,.30);
  box-shadow: 0 12px 24px rgba(0,0,0,.22);
}

.btn.small{
  padding:7px 10px;
  border-radius: 10px;
  font-size: 12px;
  font-weight: 900;
}

/* Chips */
.chips{ display:flex; gap:8px; flex-wrap:wrap; margin-top:10px; }
.chip{
  font-size:12px;
  padding:6px 10px;
  border-radius: 999px;
  border:1px solid rgba(251,146,60,.18);
  background: rgba(255,255,255,.06);
  color: rgba(255,214,165,.80);
}

/* Lists */
.list{ margin:8px 0 0 0; padding-left: 1.2em; }
.list li{ margin: 6px 0; }

/* Note */
.note{
  margin-top:10px;
  padding:10px 12px;
  border-radius: 12px;
  border:1px dashed rgba(251,146,60,.28);
  background: rgba(249,115,22,.08);
  color: rgba(255,214,165,.86);
  font-size: 13px;
}

/* Callout */
.callout{
  margin-top:10px;
  padding:12px;
  border-radius: 14px;
  border:1px solid rgba(251,146,60,.30);
  background:
    radial-gradient(420px 180px at 20% 0%, rgba(251,146,60,.14), transparent 60%),
    rgba(249,115,22,.06);
}
.callout b{ color:#fff0dc; }
.callout code{ color: #ffe0bf; }

/* Inline code row */
.inlineCode{
  display:flex; align-items:center; gap:10px; flex-wrap:wrap;
  margin-top:8px;
}

/* Code */
code{
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  font-size: 12px;
  color: var(--codeText);
}
pre.code{
  margin: 10px 0 0 0;
  padding: 12px;
  border-radius: 14px;
  border:1px solid rgba(251,146,60,.18);
  background: var(--codeBg);
  overflow:auto;
  max-height: 420px;
  box-shadow: inset 0 0 0 1px rgba(0,0,0,.18);
}

/* Code header row */
.codeHead{
  display:flex; align-items:center; justify-content:space-between;
  gap:10px;
  margin-top: 10px;
}

/* Row */
.row{ display:flex; align-items:center; gap:10px; flex-wrap:wrap; margin-top: 12px; }

/* Steps */
.steps{ margin: 10px 0 0 0; padding-left: 1.2em; }
.steps li{ margin: 8px 0; }

/* Form */
.form{ margin-top: 10px; }
.label{ display:block; font-size:12px; color: rgba(255,214,165,.78); margin-bottom: 8px; }
.formRow{ display:flex; gap:10px; }

.input{
  flex:1;
  padding:10px 12px;
  border-radius: 12px;
  border:1px solid rgba(251,146,60,.18);
  background: rgba(255,255,255,.06);
  color: var(--text);
  outline: none;
  transition: border-color .12s ease, box-shadow .12s ease, filter .12s ease;
}
.input::placeholder{ color: rgba(255,214,165,.52); }
.input:focus{
  border-color: rgba(251,146,60,.55);
  box-shadow: 0 0 0 6px rgba(249,115,22,.10);
  filter: brightness(1.02);
}

/* Result */
.result{
  margin-top:10px;
  padding:10px 12px;
  border-radius: 12px;
  border:1px solid rgba(251,146,60,.16);
  background: rgba(255,255,255,.05);
  display:none;
}
.result.ok{
  display:block;
  border-color: rgba(34,197,94,.45);
  background: rgba(34,197,94,.08);
}
.result.ng{
  display:block;
  border-color: rgba(239,68,68,.45);
  background: rgba(239,68,68,.08);
}

/* Divider */
.hr{
  height:1px;
  background: rgba(251,146,60,.16);
  margin: 14px 0;
}

/* Lessons */
.lessonList{ margin-top: 8px; display:grid; gap:12px; }
.lesson{
  border:1px solid rgba(251,146,60,.16);
  border-radius: 14px;
  background:
    radial-gradient(420px 180px at 10% 0%, rgba(251,146,60,.10), transparent 60%),
    rgba(255,255,255,.04);
  padding: 12px;
}
.lessonTop{
  display:flex; align-items:flex-start; justify-content:space-between;
  gap:10px;
}
.lessonTitle{ font-weight: 950; }
.lessonMeta{ display:flex; gap:8px; flex-wrap:wrap; justify-content:flex-end; }

.tag{
  font-size:12px;
  padding:4px 8px;
  border-radius: 999px;
  border:1px solid rgba(251,146,60,.22);
  background: rgba(249,115,22,.16);
  color: #ffe0bf;
}

.lessonDesc{ margin-top: 8px; color: rgba(255,214,165,.78); font-size: 13px; }
.lessonFoot{ margin-top: 10px; display:flex; gap:8px; flex-wrap:wrap; }

/* Empty */
.empty{
  padding: 12px;
  border-radius: 14px;
  border:1px dashed rgba(251,146,60,.22);
  background: rgba(249,115,22,.06);
  color: rgba(255,214,165,.76);
}

/* Footer */
.foot{
  padding: 14px 0 0 0;
  text-align:center;
  color: rgba(255,214,165,.66);
}

/* Toast (JS creates #toast, so only style if exists) */
#toast{
  border:1px solid rgba(251,146,60,.18) !important;
  background: rgba(0,0,0,.55) !important;
  box-shadow: 0 18px 44px rgba(0,0,0,.35), 0 0 0 6px rgba(249,115,22,.08) !important;
}

/* Accessibility: focus ring */
:where(a, button, input, textarea, select):focus-visible{
  outline: none;
  box-shadow: 0 0 0 6px rgba(249,115,22,.12);
  border-color: rgba(251,146,60,.55);
}



/* =========================
  Footer (SunStripe / Programming Lab)
  対象HTML:
  <footer class="footer">
    <div class="foot__copy">...</div>
    <nav class="foot__nav"><ul>...</ul></nav>
  </footer>
========================= */

footer{
  margin-top:18px;
  padding:18px 14px;
  border:1px solid rgba(33,115,70,.22);
  border-radius:14px;
  background:
    radial-gradient(900px 200px at 20% 0%, rgba(33,115,70,.18), transparent 65%),
    radial-gradient(700px 200px at 85% 10%, rgba(15,123,108,.12), transparent 70%),
    linear-gradient(180deg, rgba(255,255,255,.06), rgba(0,0,0,.06));
  box-shadow:0 14px 34px rgba(0,0,0,.25);
  color:var(--muted);
}

.foot__copy{
  font-size:12px;
  color:var(--muted);
  display:flex;
  flex-wrap:wrap;
  gap:6px;
  align-items:center;
  justify-content:flex-start;
  padding-bottom:12px;
  border-bottom:1px solid rgba(255,255,255,.10);
}

.foot__copy a{
  color:var(--excelWhite2, #d9ffe9);
  text-decoration:none;
  font-weight:800;
  border-bottom:1px solid rgba(33,115,70,.35);
}

.foot__copy a:hover{
  filter:brightness(1.08);
  border-bottom-color:rgba(33,115,70,.60);
}

.foot__nav{
  margin-top:12px;
}

.foot__nav ul{
  list-style:none;
  padding:0;
  margin:0;
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  align-items:center;
}

.foot__nav li{
  margin:0;
}

/* Excel風リンクチップ */
.foot__nav a{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  padding:7px 10px;
  border-radius:999px;
  border:1px solid rgba(33,115,70,.26);
  background:
    linear-gradient(180deg, rgba(33,115,70,.18), rgba(0,0,0,.06));
  color:var(--excelWhite, #f3fff8);
  font-size:12px;
  letter-spacing:.02em;
  text-decoration:none;
  transition:transform .12s ease, filter .12s ease, border-color .12s ease;
  box-shadow:0 10px 22px rgba(0,0,0,.18);
  white-space:nowrap;
}

.foot__nav a:hover{
  filter:brightness(1.08);
  border-color:rgba(33,115,70,.55);
  transform:translateY(-1px);
}

.foot__nav a:active{
  transform:translateY(0);
}

/* 今いるページが分かるように（任意：bodyにdata-current="/programming/xlsx/"とか付けると便利） */
/*
body[data-current="/programming/xlsx/"] .foot__nav a[href="/programming/xlsx/"]{
  border-color:rgba(33,115,70,.75);
  background:linear-gradient(180deg, rgba(33,115,70,.40), rgba(33,115,70,.18));
  color:var(--excelWhite2, #d9ffe9);
}
*/

/* スマホで詰まりすぎないように */
@media (max-width:560px){
  footer{
    padding:16px 12px;
  }
  .foot__nav a{
    padding:7px 9px;
    font-size:12px;
  }
}