:root {
  --paper: #faf7f0;
  --card: #ffffff;
  --ink: #1f2328;
  --mute: #6b6f76;
  --line: #e4ded2;
  --blue: #036880;
  --blue-ink: #ffffff;
  --ring: #8aabf5;
  --ring-glow: rgba(138, 171, 245, 0.35);
  --warn: #9a3b1b;
  --warn-bg: #fbeee8;
  --pin: #b07a12;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #14171a;
    --card: #1c2024;
    --ink: #e8e6e1;
    --mute: #9aa0a6;
    --line: #2c3238;
    --blue: #3aa3bd;
    --blue-ink: #0d1114;
    --ring: #7f9ff0;
    --ring-glow: rgba(127, 159, 240, 0.3);
    --warn: #f0a585;
    --warn-bg: #2e1f19;
    --pin: #e0b04a;
  }
}
:root[data-theme="dark"] {
  --paper: #14171a; --card: #1c2024; --ink: #e8e6e1; --mute: #9aa0a6; --line: #2c3238;
  --blue: #3aa3bd; --blue-ink: #0d1114; --ring: #7f9ff0; --ring-glow: rgba(127, 159, 240, 0.3);
  --warn: #f0a585; --warn-bg: #2e1f19; --pin: #e0b04a;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "IBM Plex Sans JP", system-ui, sans-serif;
  font-size: 15px;
  line-height: 1.7;
}
a { color: var(--blue); }
button, input, select, textarea { font: inherit; color: inherit; }

.top {
  max-width: 760px; margin: 0 auto; padding: 16px;
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
}
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); font-weight: 700; font-size: 20px; }
.brand img { border-radius: 9px; }
#who { display: flex; align-items: center; gap: 10px; color: var(--mute); font-size: 14px; }

main { max-width: 760px; margin: 0 auto; padding: 0 16px 48px; }
.foot { max-width: 760px; margin: 0 auto; padding: 24px 16px 40px; color: var(--mute); font-size: 13px; border-top: 1px solid var(--line); }
.foot p { margin: 4px 0; }

h1 { font-size: 22px; margin: 8px 0 4px; }
h2 { font-size: 16px; margin: 28px 0 8px; }
.lead { color: var(--mute); margin: 0 0 20px; }
.note { color: var(--mute); font-size: 13px; }

/* ---- ATOMO のログイン ---- */
.login { max-width: 460px; margin: 40px auto 0; }
.login .head { display: flex; align-items: center; gap: 16px; margin-bottom: 18px; }
.ring {
  width: 72px; height: 72px; border-radius: 50%; flex: none;
  border: 4px solid var(--ring); box-shadow: 0 0 18px var(--ring-glow);
  background: var(--card) center / cover no-repeat;
}
.ring.busy { animation: breath 1.6s ease-in-out infinite; }
@keyframes breath { 50% { box-shadow: 0 0 30px var(--ring); } }
@media (prefers-reduced-motion: reduce) { .ring.busy { animation: none; } }
.login .head b { font-size: 28px; }
.login .handle {
  width: 100%; padding: 10px 14px; border-radius: 12px;
  border: 3px solid var(--ring); background: var(--card); outline: none; font-size: 18px;
}
.atomo-btn {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 8px 20px 8px 12px; border-radius: 999px;
  border: 1.5px solid var(--line); background: var(--card); font-weight: 700; font-size: 17px; cursor: pointer;
}
.atomo-btn::before { content: ""; width: 20px; height: 20px; border-radius: 50%; border: 2.5px solid var(--ring); }
.login .row { display: flex; justify-content: flex-end; margin-top: 16px; }

/* ---- 部品 ---- */
.btn {
  border: 1.5px solid var(--line); background: var(--card); border-radius: 999px;
  padding: 6px 16px; cursor: pointer; white-space: nowrap;
}
.btn.primary { background: var(--blue); color: var(--blue-ink); border-color: var(--blue); font-weight: 700; }
.btn.small { padding: 2px 10px; font-size: 13px; }
.btn.danger { color: var(--warn); }
.btn:disabled { opacity: 0.5; cursor: default; }
.bar { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.spacer { flex: 1; }

.banner { background: var(--warn-bg); color: var(--warn); padding: 10px 14px; border-radius: 10px; margin: 12px 0; }
.ok { background: var(--card); border: 1.5px solid var(--blue); padding: 10px 14px; border-radius: 10px; margin: 12px 0; }

label.field { display: block; margin: 14px 0 4px; font-weight: 500; }
input[type="text"], input:not([type]), select, textarea {
  width: 100%; padding: 8px 12px; border-radius: 10px; border: 1.5px solid var(--line); background: var(--card);
}
textarea { min-height: 84px; resize: vertical; }
.count { text-align: right; color: var(--mute); font-size: 12px; }
.check { display: flex; gap: 8px; align-items: center; margin-top: 8px; }

.qrow { display: grid; grid-template-columns: 1fr 110px auto; gap: 8px; margin-bottom: 8px; }
@media (max-width: 520px) { .qrow { grid-template-columns: 1fr 90px auto; } }

.avatar-edit { display: flex; gap: 14px; align-items: center; }
.avatar-edit img { width: 72px; height: 72px; border-radius: 14px; object-fit: cover; background: var(--blue); }

/* ---- フィードの一覧 ---- */
.feeds { display: grid; gap: 10px; margin-top: 16px; }
.feed-card {
  display: flex; gap: 12px; align-items: center; padding: 12px; border-radius: 14px;
  background: var(--card); border: 1.5px solid var(--line); text-decoration: none; color: var(--ink);
}
.feed-card img { width: 48px; height: 48px; border-radius: 10px; flex: none; }
.feed-card .t { font-weight: 700; }
.feed-card .s { color: var(--mute); font-size: 13px; }
.tag { font-size: 12px; padding: 0 8px; border-radius: 999px; border: 1px solid var(--line); color: var(--mute); }

/* ---- 投稿 ---- */
.tabs { display: flex; gap: 4px; border-bottom: 1.5px solid var(--line); margin: 8px 0 12px; }
.tabs button { border: none; background: none; padding: 6px 12px; cursor: pointer; color: var(--mute); border-bottom: 3px solid transparent; margin-bottom: -1.5px; }
.tabs button.on { color: var(--ink); border-color: var(--blue); font-weight: 700; }
.posts { display: grid; gap: 8px; }
.post { background: var(--card); border: 1.5px solid var(--line); border-radius: 12px; padding: 10px 12px; }
.post.pinned { border-color: var(--pin); }
.post .h { display: flex; gap: 8px; align-items: center; font-size: 13px; color: var(--mute); min-width: 0; }
.post .h img { width: 22px; height: 22px; border-radius: 50%; flex: none; }
.post .h b { color: var(--ink); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.post .h .handle-s { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.post .x { white-space: pre-wrap; overflow-wrap: anywhere; margin: 4px 0; }
.post .m { color: var(--mute); font-size: 12px; }
.post .bar { margin-top: 4px; }
.empty { color: var(--mute); padding: 12px 0; }
.more { margin-top: 10px; }