/*
  Designed by instan <https://instan.fc2.page>
  005 — riso print 風（リソグラフ印刷の蛍光色 + 版ズレ + 紙テクスチャ）
*/

/* ===== カラー・フォントの設定（ここを変えると全体の見た目が変わります） ===== */
:root {
  color-scheme: light dark;

  /* ライトモードの色（古紙色背景 + リソグラフの蛍光色） */
  --color-bg: #f6f1e6;
  --color-paper: #eee7d6;
  --color-text: #1a1a1a;
  --color-muted: #5a5852;
  --color-line: #1a1a1a;
  --color-pink: #ff4f8b;
  --color-blue: #3b3fc4;
  --color-yellow: #f5c100;

  /* フォント */
  --font-sans: "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  --font-mono: "IBM Plex Mono", "Noto Sans JP", ui-monospace, monospace;
  --font-body: var(--font-sans);

  /* レイアウト */
  --content-width: 1080px;
  --reading-width: 36rem;
  --header-height: 56px;

  accent-color: var(--color-pink);
}

/* ダークモード（OS のダーク設定が ON のときだけ上の色を上書き） */
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #161614;
    --color-paper: #1f1e1a;
    --color-text: #f3eedc;
    --color-muted: #a8a392;
    --color-line: #f3eedc;
    --color-pink: #ff6ea0;
    --color-blue: #7a8cff;
    --color-yellow: #ffd84a;
  }
}

/* Scroll-driven animation 用の registered custom properties */
@property --header-bg-alpha {
  syntax: "<number>";
  inherits: false;
  initial-value: 0;
}

@property --drawer-backdrop {
  syntax: "<number>";
  inherits: true;
  initial-value: 0;
}

/* ===== 文字まわりの基本設定 ===== */
body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 0.95rem;
  line-height: 1.7;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  /* ハーフトーン点 + 紙ノイズ */
  background-image:
    radial-gradient(rgba(0, 0, 0, 0.06) 1px, transparent 1.4px),
    url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='200' height='200'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='1.1' numOctaves='2'/><feColorMatrix values='0 0 0 0 0  0 0 0 0 0  0 0 0 0 0  0 0 0 0.22 0'/></filter><rect width='100%25' height='100%25' filter='url(%23n)' opacity='0.4'/></svg>");
  background-size:
    4px 4px,
    180px 180px;
}

@media (prefers-color-scheme: dark) {
  body {
    background-image:
      radial-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1.4px),
      url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='200' height='200'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='1.1' numOctaves='2'/><feColorMatrix values='0 0 0 0 1  0 0 0 0 1  0 0 0 0 1  0 0 0 0.15 0'/></filter><rect width='100%25' height='100%25' filter='url(%23n)' opacity='0.4'/></svg>");
  }
}

a {
  color: var(--color-text);
  text-decoration-color: var(--color-blue);
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--color-blue);
}

:focus-visible {
  outline: 2px solid var(--color-pink);
  outline-offset: 2px;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.4;
  text-wrap: balance;
}

h1 {
  font-size: clamp(1.75rem, 4.5vw, 2.25rem);
  font-weight: 900;
  margin: 2.5rem 0 1.25rem;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--color-line);
  letter-spacing: -0.01em;
  text-shadow:
    -2px 1px 0 var(--color-pink),
    2px -1px 0 var(--color-blue);
}

@media (prefers-color-scheme: dark) {
  h1 {
    text-shadow: none;
  }
}

h2 {
  font-size: 1.4rem;
  margin: 2.25rem 0 1rem;
  padding-bottom: 0.45rem;
  border-bottom: 2px solid var(--color-line);
}

h3 {
  font-size: 1.15rem;
  margin: 2rem 0 0.75rem;
  padding-left: 0.6rem;
  border-left: 4px solid var(--color-pink);
}

h4 {
  font-size: 1rem;
  margin: 1.75rem 0 0.5rem;
  color: var(--color-pink);
  letter-spacing: 0.05em;
}

h5 {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 500;
  margin: 1.5rem 0 0.5rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

h6 {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  margin: 1.25rem 0 0.4rem;
  color: var(--color-muted);
  letter-spacing: 0.22em;
  text-transform: uppercase;
}

p + p {
  margin-top: 1em;
}

/* ===== 強調 / 引用 / 区切り / コード（本文中で使う inline / block 要素） ===== */
em {
  font-style: normal;
  background: linear-gradient(transparent 60%, var(--color-yellow) 60% 94%, transparent 94%);
  padding: 0 2px;
}

strong {
  font-weight: 700;
  color: var(--color-pink);
  text-shadow: 1.5px 0 0 var(--color-blue);
  mix-blend-mode: multiply;
}

@media (prefers-color-scheme: dark) {
  strong {
    mix-blend-mode: normal;
    text-shadow: none;
    text-decoration: underline;
    text-decoration-color: var(--color-blue);
    text-decoration-thickness: 2px;
  }
}

/* mark: 手描きの蛍光ペン風（ラフな縁を SVG 背景に焼き込み、box-decoration-break
   で折り返し各行に追従。デフォルト=ピンク、.hl-blue / .hl-yellow で色替え）。
   蛍光ペンらしく半透明にして、本文の文字色のまま読めるようにしている。 */
mark {
  background-color: transparent;
  background-repeat: no-repeat;
  background-position: center;
  background-size: 100% 100%;
  -webkit-box-decoration-break: clone;
  box-decoration-break: clone;
  color: inherit;
  padding: 0.04em 0.3em;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 40' preserveAspectRatio='none'%3E%3Cdefs%3E%3Cfilter id='r' x='-15%25' y='-15%25' width='130%25' height='130%25'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.055 .09' numOctaves='3' seed='8' result='n'/%3E%3CfeDisplacementMap in='SourceGraphic' in2='n' scale='5'/%3E%3C/filter%3E%3ClinearGradient id='g' x1='0' y1='0' x2='0' y2='1'%3E%3Cstop offset='0' stop-color='%23fff' stop-opacity='.28'/%3E%3Cstop offset='1' stop-color='%23000' stop-opacity='.12'/%3E%3C/linearGradient%3E%3C/defs%3E%3Cg filter='url(%23r)'%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='%23ff4f8b' fill-opacity='.55'/%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='url(%23g)'/%3E%3C/g%3E%3C/svg%3E");
}

mark.hl-blue {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 40' preserveAspectRatio='none'%3E%3Cdefs%3E%3Cfilter id='r' x='-15%25' y='-15%25' width='130%25' height='130%25'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.055 .09' numOctaves='3' seed='7' result='n'/%3E%3CfeDisplacementMap in='SourceGraphic' in2='n' scale='5'/%3E%3C/filter%3E%3ClinearGradient id='g' x1='0' y1='0' x2='0' y2='1'%3E%3Cstop offset='0' stop-color='%23fff' stop-opacity='.28'/%3E%3Cstop offset='1' stop-color='%23000' stop-opacity='.12'/%3E%3C/linearGradient%3E%3C/defs%3E%3Cg filter='url(%23r)'%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='%233b3fc4' fill-opacity='.50'/%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='url(%23g)'/%3E%3C/g%3E%3C/svg%3E");
}

mark.hl-yellow {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 40' preserveAspectRatio='none'%3E%3Cdefs%3E%3Cfilter id='r' x='-15%25' y='-15%25' width='130%25' height='130%25'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.055 .09' numOctaves='3' seed='4' result='n'/%3E%3CfeDisplacementMap in='SourceGraphic' in2='n' scale='5'/%3E%3C/filter%3E%3ClinearGradient id='g' x1='0' y1='0' x2='0' y2='1'%3E%3Cstop offset='0' stop-color='%23fff' stop-opacity='.28'/%3E%3Cstop offset='1' stop-color='%23000' stop-opacity='.12'/%3E%3C/linearGradient%3E%3C/defs%3E%3Cg filter='url(%23r)'%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='%23f5c100' fill-opacity='.60'/%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='url(%23g)'/%3E%3C/g%3E%3C/svg%3E");
}

@media (prefers-color-scheme: dark) {
  mark {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 40' preserveAspectRatio='none'%3E%3Cdefs%3E%3Cfilter id='r' x='-15%25' y='-15%25' width='130%25' height='130%25'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.055 .09' numOctaves='3' seed='8' result='n'/%3E%3CfeDisplacementMap in='SourceGraphic' in2='n' scale='5'/%3E%3C/filter%3E%3ClinearGradient id='g' x1='0' y1='0' x2='0' y2='1'%3E%3Cstop offset='0' stop-color='%23fff' stop-opacity='.28'/%3E%3Cstop offset='1' stop-color='%23000' stop-opacity='.12'/%3E%3C/linearGradient%3E%3C/defs%3E%3Cg filter='url(%23r)'%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='%23ff6ea0' fill-opacity='.50'/%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='url(%23g)'/%3E%3C/g%3E%3C/svg%3E");
  }

  mark.hl-blue {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 40' preserveAspectRatio='none'%3E%3Cdefs%3E%3Cfilter id='r' x='-15%25' y='-15%25' width='130%25' height='130%25'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.055 .09' numOctaves='3' seed='7' result='n'/%3E%3CfeDisplacementMap in='SourceGraphic' in2='n' scale='5'/%3E%3C/filter%3E%3ClinearGradient id='g' x1='0' y1='0' x2='0' y2='1'%3E%3Cstop offset='0' stop-color='%23fff' stop-opacity='.28'/%3E%3Cstop offset='1' stop-color='%23000' stop-opacity='.12'/%3E%3C/linearGradient%3E%3C/defs%3E%3Cg filter='url(%23r)'%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='%237a8cff' fill-opacity='.48'/%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='url(%23g)'/%3E%3C/g%3E%3C/svg%3E");
  }

  mark.hl-yellow {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 40' preserveAspectRatio='none'%3E%3Cdefs%3E%3Cfilter id='r' x='-15%25' y='-15%25' width='130%25' height='130%25'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.055 .09' numOctaves='3' seed='4' result='n'/%3E%3CfeDisplacementMap in='SourceGraphic' in2='n' scale='5'/%3E%3C/filter%3E%3ClinearGradient id='g' x1='0' y1='0' x2='0' y2='1'%3E%3Cstop offset='0' stop-color='%23fff' stop-opacity='.28'/%3E%3Cstop offset='1' stop-color='%23000' stop-opacity='.12'/%3E%3C/linearGradient%3E%3C/defs%3E%3Cg filter='url(%23r)'%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='%23ffd84a' fill-opacity='.52'/%3E%3Crect x='3' y='5' width='114' height='30' rx='6' fill='url(%23g)'/%3E%3C/g%3E%3C/svg%3E");
  }
}

blockquote {
  margin: 1.5em 0;
  padding: 0.75em 1.25em;
  border-left: 4px solid var(--color-pink);
  background: color-mix(in oklab, var(--color-pink) 8%, transparent);
  font-style: italic;
}

ul {
  margin: 1em 0;
  padding-left: 1.75em;
  list-style: square;
}

ol {
  margin: 1em 0;
  padding-left: 1.75em;
  list-style: decimal;
}

dl {
  margin: 1em 0;
}

dt {
  font-weight: 700;
  margin-top: 0.75em;
  color: var(--color-blue);
}

dd {
  margin-left: 1.5em;
}

table {
  width: 100%;
  margin: 1.5em 0;
  border-collapse: collapse;
  font-size: 0.9rem;
}

th,
td {
  padding: 0.55em 0.85em;
  border-bottom: 1.5px solid var(--color-line);
  text-align: left;
}

th {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-muted);
}

hr {
  border: 0;
  border-top: 2px solid var(--color-line);
  margin: 2em 0;
}

code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: color-mix(in oklab, var(--color-text) 10%, transparent);
  padding: 0.1em 0.35em;
}

pre {
  margin: 1.5em 0;
  padding: 1em;
  background: color-mix(in oklab, var(--color-text) 6%, transparent);
  border: 1.5px solid var(--color-line);
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.55;
}

pre code {
  background: transparent;
  padding: 0;
}

img {
  max-width: 100%;
  height: auto;
}

/* ===== フォーム要素 ===== */
label {
  display: block;
  font-size: 0.85rem;
  color: var(--color-muted);
  margin-bottom: 0.3em;
}

input[type="text"],
input[type="password"],
input[type="number"],
input[type="email"],
input[type="search"],
input[type="url"],
input[type="tel"],
textarea,
select {
  -webkit-appearance: none;
  border: 1px solid var(--color-line);
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 0.95rem;
  padding: 0.5rem;
  border-radius: 0;
}

textarea {
  width: 100%;
  min-height: 4rem;
  margin: 0.5rem 0;
  resize: vertical;
}

select {
  padding-right: 1.75rem;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='235a5852' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.5rem center;
}

button,
input[type="button"],
input[type="submit"],
input[type="reset"] {
  -webkit-appearance: none;
  background: var(--color-bg);
  color: var(--color-text);
  border: 1px solid var(--color-line);
  padding: 0.5rem 1.5rem;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  cursor: pointer;
  touch-action: manipulation;
  letter-spacing: 0.05em;
}

button:hover,
input[type="button"]:hover,
input[type="submit"]:hover,
input[type="reset"]:hover {
  border-color: var(--color-pink);
}

.form-actions {
  display: block;
  text-align: center;
}

/* ===== 画面上部の固定ヘッダー（004 共通シェル + リソ装飾） ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  height: var(--header-height);
  border-bottom: 1px solid transparent;
  background: color-mix(in oklab, var(--color-bg) calc(var(--header-bg-alpha) * 100%), transparent);
}

@supports (animation-timeline: scroll()) {
  .site-header {
    animation: header-solidify linear both;
    animation-timeline: scroll(root);
    animation-range: 0 80px;
  }

  @keyframes header-solidify {
    from {
      --header-bg-alpha: 0;
      border-bottom-color: transparent;
    }
    to {
      --header-bg-alpha: 1;
      border-bottom-color: var(--color-line);
    }
  }
}

.site-header.scrolled {
  --header-bg-alpha: 1;
  border-bottom-color: var(--color-line);
}

.site-header-inner {
  max-width: var(--content-width);
  margin: 0 auto;
  height: 100%;
  padding: 0 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.site-name {
  font-size: 1.2rem;
  font-weight: 900;
  letter-spacing: -0.01em;
  text-decoration: none;
  color: var(--color-text);
  /* 版ズレ風: pink + blue を text-shadow で重ねる */
  text-shadow:
    -2px 1px 0 var(--color-pink),
    2px -1px 0 var(--color-blue);
}

/* ===== ナビゲーション =====
   1 つの <nav class="site-nav"> をリンク編集の唯一の場所として運用する。
   SP では .drawer を popover + transform: translateX で右からスライドインするドロワー化、
   PC では .drawer を display: contents でフラット化してヘッダー内インラインにする。 */

.drawer {
  --drawer-width: min(20rem, 80dvw);
  position: fixed;
  inset: 0 0 0 auto;
  width: var(--drawer-width);
  height: 100dvh;
  margin: 0;
  padding: 0;
  border: 0;
  background: var(--color-bg);
  background-image: radial-gradient(rgba(0, 0, 0, 0.06) 1px, transparent 1.4px);
  background-size: 4px 4px;
  border-left: 2px solid var(--color-line);
  box-shadow:
    -6px 0 0 var(--color-blue),
    -12px 0 30px -10px rgba(0, 0, 0, 0.3);
  color: var(--color-text);
  overflow: hidden;
  transform: translateX(105%);
  transition:
    transform 0.28s cubic-bezier(0.3, 0.7, 0.3, 1),
    display 0.28s allow-discrete,
    overlay 0.28s allow-discrete;
}

.drawer:popover-open {
  transform: translateX(0);
}

@starting-style {
  .drawer:popover-open {
    transform: translateX(105%);
  }
}

.drawer::backdrop {
  background: rgba(0, 0, 0, 0.5);
  opacity: 0;
  transition:
    opacity 0.28s ease,
    display 0.28s allow-discrete,
    overlay 0.28s allow-discrete;
}

.drawer:popover-open::backdrop {
  opacity: 1;
}

@starting-style {
  .drawer:popover-open::backdrop {
    opacity: 0;
  }
}

.site-nav {
  height: 100%;
  overflow-y: auto;
  scrollbar-width: none;
}

.site-nav::-webkit-scrollbar {
  display: none;
}

.site-nav ul {
  padding: 4rem 1.5rem 1.5rem;
  display: flex;
  flex-direction: column;
  /* base ul の list-style / margin を打ち消す */
  list-style: none;
  margin: 0;
}

.site-nav a {
  display: block;
  padding: 0.9rem 0.5rem;
  font-size: 1rem;
  font-weight: 500;
  text-decoration: none;
  color: var(--color-text);
  border-bottom: 1px dashed var(--color-line);
  letter-spacing: 0.05em;
}

.site-nav a:hover {
  background: var(--color-yellow);
  color: var(--color-text);
}

.site-nav a[aria-current] {
  background: var(--color-text);
  color: var(--color-bg);
}

.drawer-close {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1.5px solid var(--color-line);
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 16px;
  cursor: pointer;
  touch-action: manipulation;
  z-index: 1;
}

.drawer-close:hover {
  background: var(--color-yellow);
}

.nav-toggle {
  touch-action: manipulation;
  display: inline-flex;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  background: var(--color-bg);
  border: 2px solid var(--color-line);
  cursor: pointer;
  box-shadow: 3px 3px 0 var(--color-pink);
  transition:
    transform 0.12s,
    box-shadow 0.12s;
  color: var(--color-text);
}

.nav-toggle:hover {
  transform: translate(-2px, -2px);
  box-shadow: 4px 4px 0 var(--color-pink);
}

/* PC: ヘッダー内インラインに切り替え（768px以上）
   drawer の box を display: contents で消すことで、
   中の <nav> が .site-header-inner の flex 子として横並びになる。 */
@media (min-width: 768px) {
  .drawer {
    display: contents;
  }

  .site-nav {
    display: block;
    height: auto;
    overflow: visible;
  }

  .site-nav ul {
    flex-direction: row;
    gap: 0;
    padding: 0;
  }

  .site-nav a {
    display: inline-flex;
    align-items: center;
    padding: 6px 12px;
    border-bottom: 0;
    border-left: 1px solid var(--color-line);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.18em;
    text-transform: uppercase;
  }

  .site-nav ul li:first-child a {
    border-left: 0;
  }

  .site-nav a:hover {
    background: var(--color-yellow);
  }

  .site-nav a[aria-current] {
    background: var(--color-text);
    color: var(--color-bg);
  }

  .drawer-close,
  .nav-toggle {
    display: none;
  }
}

/* ===== 本文エリアの共通レイアウト（全ページ共通） ===== */
.site-main {
  flex: 1;
  width: 100%;
  max-width: var(--content-width);
  margin: 1.5rem auto;
  padding: 2rem 1.75rem 2.5rem;
  background: var(--color-paper);
  border: 2px solid var(--color-line);
  box-shadow: 6px 6px 0 var(--color-blue);
  position: relative;
}

.site-main::before {
  content: "RISO PRINT · ed. 005 / 100";
  position: absolute;
  top: -12px;
  left: 24px;
  background: var(--color-bg);
  padding: 2px 8px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--color-muted);
  border: 1.5px solid var(--color-line);
}

section + section {
  margin-top: 2.5rem;
}

.page-title {
  font-size: 1.75rem;
  font-weight: 900;
  /* base h1 の margin shorthand / text-shadow を打ち消す */
  margin: 0 0 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--color-line);
  letter-spacing: -0.01em;
  text-shadow: none;
}

.section-title {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--color-text);
  color: var(--color-bg);
  display: inline-block;
  padding: 4px 12px;
  /* base h2 の margin / 罫線を打ち消す */
  margin: 0 0 1rem;
  padding-bottom: 4px;
  border-bottom: 0;
}

/* ===== トップページの大見出しエリア ===== */
.hero {
  padding: 1.5rem 0 2rem;
  margin-bottom: 1.5rem;
  border-bottom: 2px solid var(--color-line);
}

.hero-title {
  font-size: clamp(2rem, 6vw, 3rem);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1;
  /* base h1 の margin shorthand / 罫線を打ち消す（text-shadow は class 側を使う） */
  margin: 0 0 0.75rem;
  padding-bottom: 0;
  border-bottom: 0;
  text-shadow:
    -3px 2px 0 var(--color-pink),
    3px -2px 0 var(--color-blue);
}

/* ===== トップページの各セクション ===== */
.top-section {
  margin-top: 2.5rem;
}

.top-section-more {
  margin-top: 1rem;
  text-align: right;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.top-section-more a {
  background: var(--color-text);
  color: var(--color-bg);
  text-decoration: none;
  padding: 6px 14px;
  display: inline-block;
  transition:
    transform 0.12s,
    box-shadow 0.12s;
}

.top-section-more a:hover {
  transform: translate(-2px, -2px);
  box-shadow: 3px 3px 0 var(--color-pink);
  color: var(--color-bg);
}

.top-news-list {
  display: flex;
  flex-direction: column;
  /* base ul の list-style / padding / margin を打ち消す */
  list-style: none;
  margin: 0;
  padding-left: 0;
}

.top-news-item {
  display: grid;
  grid-template-columns: 7rem 1fr;
  gap: 1rem;
  padding: 0.5rem 0;
  font-size: 0.9rem;
  border-bottom: 1px dashed var(--color-line);
}

.top-news-item:last-child {
  border-bottom: 0;
}

.top-news-item time {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--color-muted);
}

/* ===== 2 カラム レイアウト（top の feed-sidebar pattern） ===== */
.layout {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 2.5rem;
  margin-top: 1.5rem;
}

.layout-main {
  min-width: 0;
}

@media (max-width: 780px) {
  .layout {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

/* ===== サイドバー（005 独自パーツ。class 名は将来 parts/ へ抽出予定） ===== */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

.side-card {
  border: 2px solid var(--color-line);
  background: var(--color-bg);
  padding: 1rem 1rem 1.25rem;
  position: relative;
}

.side-card-title {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 0.7rem;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  margin: -1.75rem 0 0.875rem;
  background: var(--color-text);
  color: var(--color-bg);
  display: inline-block;
  padding: 4px 10px;
  /* base h3 の罫線 / padding-left を打ち消す */
  padding-left: 10px;
  border-left: 0;
}

.side-card-pink {
  box-shadow: 3px 3px 0 var(--color-pink);
}

.side-card-blue {
  box-shadow: 3px 3px 0 var(--color-blue);
}

.side-card-yellow {
  box-shadow: 3px 3px 0 var(--color-yellow);
}

/* about-card (sidebar 用 about 縮約版) */
.about-card .profile {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}

.about-card .avatar {
  width: 54px;
  height: 54px;
  background: radial-gradient(var(--color-pink) 30%, transparent 32%), var(--color-blue);
  background-size: 5px 5px;
  border: 1.5px solid var(--color-line);
  mix-blend-mode: multiply;
  flex: 0 0 auto;
}

@media (prefers-color-scheme: dark) {
  .about-card .avatar {
    mix-blend-mode: normal;
  }
}

.about-card .profile-name {
  font-weight: 700;
  font-size: 0.95rem;
}

.about-card .profile-handle {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
}

.about-card-text {
  font-size: 0.85rem;
  margin: 0;
  color: var(--color-text);
}

/* links-list (sidebar 用) */
.links-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.links-list li {
  border-top: 1px dashed var(--color-line);
}

.links-list li:first-child {
  border-top: 0;
}

.links-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  text-decoration: none;
  color: var(--color-text);
  font-size: 0.9rem;
  padding: 0.5rem 4px;
}

.links-list a::after {
  content: "↗";
  color: var(--color-blue);
  font-family: var(--font-mono);
}

.links-list a:hover {
  background: var(--color-yellow);
  padding-left: 8px;
  transition: padding 0.12s;
}

/* banners-list (sidebar 用) */
.banners-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
}

.banner {
  display: block;
  line-height: 0;
}

.banner img {
  display: block;
  width: 200px;
  max-width: 100%;
  height: auto;
}

.banner:hover {
  opacity: 0.85;
}

.banners-note {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--color-muted);
  letter-spacing: 0.15em;
  margin: 10px 0 0;
  text-transform: uppercase;
}

/* mail-form (sidebar 用) */
.mail-form {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.mail-form label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--color-muted);
  text-transform: uppercase;
}

.mail-form input,
.mail-form textarea {
  background: var(--color-paper);
  border: 1.5px solid var(--color-line);
  padding: 8px 10px;
  color: var(--color-text);
  font-size: 0.85rem;
}

.mail-form textarea {
  min-height: 70px;
  resize: vertical;
}

.mail-form button {
  align-self: flex-start;
  background: var(--color-text);
  color: var(--color-bg);
  border: 1.5px solid var(--color-line);
  padding: 8px 18px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  cursor: pointer;
  touch-action: manipulation;
  transition:
    transform 0.12s,
    box-shadow 0.12s;
}

.mail-form button:hover {
  transform: translate(-2px, -2px);
  box-shadow: 3px 3px 0 var(--color-pink);
}

.clap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--color-line);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
}

.clap-button {
  background: var(--color-yellow);
  color: var(--color-text);
  border: 1.5px solid var(--color-line);
  padding: 6px 14px;
  font-size: 0.9rem;
  cursor: pointer;
  touch-action: manipulation;
}

.clap-button:hover {
  background: var(--color-pink);
  color: var(--color-bg);
  mix-blend-mode: multiply;
}

@media (prefers-color-scheme: dark) {
  .clap-button:hover {
    mix-blend-mode: normal;
  }
}

/* ===== 作品一覧ページ（/novels/） ===== */
.novels-list {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  /* base ul の list-style / padding / margin を打ち消す */
  list-style: none;
  margin: 0;
  padding-left: 0;
}

.novel-card {
  padding: 1.25rem;
  border: 2px solid var(--color-line);
  background: var(--color-bg);
  position: relative;
  box-shadow: 3px 3px 0 var(--color-pink);
  transition:
    transform 0.12s,
    box-shadow 0.12s;
}

.novel-card:nth-child(3n + 2) {
  box-shadow: 3px 3px 0 var(--color-blue);
}

.novel-card:nth-child(3n) {
  box-shadow: 3px 3px 0 var(--color-yellow);
}

.novel-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 var(--color-pink);
}

.novel-card:nth-child(3n + 2):hover {
  box-shadow: 5px 5px 0 var(--color-blue);
}

.novel-card:nth-child(3n):hover {
  box-shadow: 5px 5px 0 var(--color-yellow);
}

.novel-card a {
  display: block;
  text-decoration: none;
  color: inherit;
}

.novel-card-title {
  font-size: 1.2rem;
  font-weight: 700;
  /* base h2 / h3 双方の margin / 罫線を打ち消す（カード内タイトル） */
  margin: 0 0 0.5rem;
  padding-bottom: 0;
  border-bottom: 0;
  padding-left: 0;
  border-left: 0;
}

.novel-card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--color-muted);
  margin-bottom: 0.75rem;
}

.novel-card-cat {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--color-muted);
}

.novel-card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 0.75rem;
}

.novel-tag {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  background: var(--color-text);
  color: var(--color-bg);
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.novel-card-excerpt {
  font-size: 0.9rem;
  color: var(--color-text);
  margin: 0;
}

/* ===== 作品本文ページ（/novels/NNN.html） ===== */
.novel-back {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  display: inline-block;
}

.novel-header {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 2px solid var(--color-line);
}

.novel-title {
  font-size: 1.75rem;
  font-weight: 900;
  /* base h1 の罫線 / text-shadow は .novel-header 側で持つので打ち消す */
  margin: 0 0 0.75rem;
  padding-bottom: 0;
  border-bottom: 0;
  text-shadow: none;
}

.novel-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--color-muted);
}

.caution {
  margin: 1.5rem 0;
  padding: 1rem 1.25rem;
  border: 2px solid var(--color-pink);
  background: color-mix(in oklab, var(--color-pink) 8%, transparent);
  font-size: 0.9rem;
}

.caution-title {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-pink);
  margin-bottom: 0.25rem;
}

.novel-body {
  max-width: var(--reading-width);
  margin: 2rem auto 3rem;
  font-size: 0.95rem;
  line-height: 1.95;
  text-align: justify;
  text-align-last: left;
}

.novel-body p + p {
  margin-top: 1.4em;
  text-indent: 1em;
}

.novel-body p:first-child {
  text-indent: 0;
}

.novel-footer {
  text-align: center;
  padding-top: 2rem;
  border-top: 2px solid var(--color-line);
}

.novel-footer-back {
  display: inline-block;
  padding: 0.75rem 2rem;
  background: var(--color-text);
  color: var(--color-bg);
  border: 2px solid var(--color-line);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  transition:
    transform 0.12s,
    box-shadow 0.12s;
}

.novel-footer-back:hover {
  transform: translate(-2px, -2px);
  box-shadow: 3px 3px 0 var(--color-pink);
  color: var(--color-bg);
}

/* ===== お知らせ一覧ページ（/news/） ===== */
.news-list {
  display: flex;
  flex-direction: column;
  /* base ul の list-style / padding / margin を打ち消す */
  list-style: none;
  margin: 0;
  padding-left: 0;
}

.news-item {
  padding: 1.25rem 0;
  border-bottom: 1px dashed var(--color-line);
  display: grid;
  grid-template-columns: 7rem 1fr;
  gap: 1rem;
  align-items: start;
}

.news-date {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--color-muted);
}

.news-body {
  font-size: 0.95rem;
}

@media (max-width: 600px) {
  .news-item {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }
  .top-news-item {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }
}

/* ===== つぶやきタイムライン ===== */
.timeline {
  /* base ul の list-style / padding を打ち消す */
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
}

.timeline-item {
  padding: 1.5rem 0;
  border-bottom: 1px dashed var(--color-line);
}

.timeline-item:last-child {
  border-bottom: 0;
}

.timeline-item.is-pinned {
  border: 2px solid var(--color-line);
  box-shadow: 3px 3px 0 var(--color-pink);
  padding: 1.25rem 1rem;
  margin-bottom: 0.5rem;
}

.timeline-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.4rem 0.875rem;
  margin-bottom: 0.625rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-muted);
}

.timeline-pin {
  background: var(--color-text);
  color: var(--color-bg);
  padding: 2px 8px;
  letter-spacing: 0.2em;
}

.timeline-time {
  color: var(--color-muted);
}

.timeline-body {
  font-size: 0.95rem;
  line-height: 1.85;
}

.timeline-body p {
  margin: 0 0 0.75em;
  text-wrap: pretty;
}

.timeline-body p:last-child {
  margin-bottom: 0;
}

.timeline-media {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 0.625rem;
}

/* 画像が 1 枚のときは横いっぱいに引き伸ばさない */
.timeline-media:has(a:only-child) {
  grid-template-columns: minmax(0, 320px);
}

.timeline-media a {
  display: block;
}

.timeline-media img {
  display: block;
  width: 100%;
  height: auto;
  border: 2px solid var(--color-line);
  box-shadow: 2px 2px 0 var(--color-blue);
}

/* ===== aboutページ ===== */
.about-section {
  margin-bottom: 2rem;
}

.about-list {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.5rem 1.5rem;
  margin-top: 1rem;
}

.about-list dt {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--color-muted);
  text-transform: uppercase;
  /* base dt の margin-top / color を打ち消す（grid 表示で不要） */
  margin-top: 0;
}

/* ===== 「まだありません」表示用（一覧が空のとき） ===== */
.empty {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--color-muted);
  font-style: italic;
}

/* ===== SP 調整 ===== */
@media (max-width: 600px) {
  .site-main {
    padding: 1.75rem 1.25rem 2rem;
    margin: 1rem auto 1.5rem;
  }
  .site-main::before {
    left: 14px;
    font-size: 9px;
  }
}