/*
Theme Name: 理解をかたちに
Author: 菜の花
Description: 技術メモ・制作ノートなどを書く個人ブログのテーマ
Version: 1.0
*/

/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --white:       #ffffff;
  --bg:          #ffffff;
  --fg:          #1c1c1a;
  --muted:       #7a7a72;
  --border:      rgba(0,0,0,0.08);
  --card-bg:     #fafaf8;
  --section-bg:  #f4f4f0;

  --green:       #b8d4c4;
  --green-pale:  #e8f2ec;
  --green-deep:  #3a6b53;
  --yellow:      #e8c840;
  --yellow-pale: #faf5d8;
  --sand:        #d4c5b0;

  --font-body:    'Noto Sans JP', sans-serif;
  --font-heading: 'Noto Serif JP', serif;

  --max-w: 960px;
  --gap:   2.5rem;
}

html { font-size: 16px; }
body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--fg);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

/* ===== LAYOUT ===== */
.inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
}
.main-wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 3rem 1.5rem 4rem;
}
.layout {
  display: grid;
  grid-template-columns: 1fr 240px;
  gap: 3.5rem;
  align-items: start;
}

/* ===== HEADER ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--border);
}
.site-header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  padding-bottom: 1rem;
}
.site-title { display: flex; flex-direction: column; gap: 4px; }
.site-title__main {
  font-family: var(--font-heading);
  font-size: 1rem;
  letter-spacing: 0.04em;
  color: var(--fg);
  transition: color .2s;
}
.site-title:hover .site-title__main { color: var(--green-deep); }
.site-title__sub { font-size: 0.875rem; color: var(--muted); }

.nav { display: flex; align-items: center; gap: 1.5rem; }
.nav li { list-style: none; }
.nav__link,
.nav li a {
  font-size: 0.875rem;
  color: var(--muted);
  transition: color .2s;
  position: relative;
  padding-bottom: 2px;
}
.nav__link:hover,
.nav li a:hover { color: var(--green-deep); }
.nav__link--active,
.nav .current-menu-item > a {
  color: var(--green-deep);
}
.nav__link--active::after,
.nav .current-menu-item > a::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 1px;
  background: var(--green);
  border-radius: 1px;
}

/* Mobile toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 22px; height: 1.5px;
  background: var(--muted);
  border-radius: 2px;
  transition: background .2s;
}
.nav-toggle:hover span { background: var(--fg); }

.nav-mobile {
  display: none;
  flex-direction: column;
  border-top: 1px solid var(--border);
  background: var(--white);
}
.nav-mobile.is-open { display: flex; }
.nav-mobile li { list-style: none; }
.nav-mobile__link,
.nav-mobile li a {
  padding: .75rem 1.5rem;
  font-size: 0.9rem;
  color: var(--muted);
  border-bottom: 1px solid var(--border);
  transition: color .2s, background .2s;
}
.nav-mobile__link:hover,
.nav-mobile li a:hover { color: var(--green-deep); background: var(--green-pale); }

/* ===== HERO ===== */
.hero { margin-bottom: 3rem; }
.hero__accent {
  width: 2rem; height: 4px;
  background: var(--yellow);
  border-radius: 2px;
  margin-bottom: 1.25rem;
}
.hero__title {
  font-family: var(--font-heading);
  font-size: 1.6rem;
  font-weight: 500;
  line-height: 1.7;
  letter-spacing: 0.03em;
  color: var(--fg);
  margin-bottom: .75rem;
}
.hero__desc {
  font-size: 0.88rem;
  line-height: 1.9;
  color: var(--muted);
}

/* ===== SECTION LABEL ===== */
.section-label {
  font-size: 0.875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: .75rem;
}

/* ===== FEATURED SECTION ===== */
.featured-section {
  margin-bottom: 2.5rem;
}

.featured-badge {
  position: absolute;
  top: 0;
  left: 0;
  background: var(--yellow);
  color: var(--fg);
  font-family: var(--font-heading);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  padding: 0.28rem 0.7rem;
  border-bottom-right-radius: 6px;
  z-index: 1;
}

/* ===== CARDS ===== */
.articles { display: flex; flex-direction: column; gap: 1rem; }

.card {
  display: flex;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  position: relative;
  cursor: pointer;
  transition: box-shadow .25s, transform .2s;
}
.card:hover { box-shadow: 0 4px 16px rgba(0,0,0,.06); transform: translateY(-1px); }

/* Geometric thumbnail */
.card__thumb {
  width: 120px;
  flex-shrink: 0;
}
.card--featured .card__thumb { width: 160px; }

.card__thumb--green {
  background:
    radial-gradient(circle at 30% 25%, var(--green) 18px, transparent 18px),
    radial-gradient(circle at 75% 60%, var(--green) 12px, transparent 12px),
    radial-gradient(circle at 50% 85%, var(--green) 8px, transparent 8px),
    radial-gradient(circle at 15% 70%, rgba(184,212,196,.4) 14px, transparent 14px),
    radial-gradient(circle at 85% 20%, rgba(184,212,196,.4) 10px, transparent 10px),
    var(--green-pale);
}
.card__thumb--yellow {
  background:
    linear-gradient(135deg, var(--yellow) 25%, transparent 25%) -20px 0 / 40px 40px,
    linear-gradient(225deg, var(--yellow) 25%, transparent 25%) -20px 0 / 40px 40px,
    linear-gradient(315deg, rgba(232,200,64,.4) 25%, transparent 25%) 0 0 / 40px 40px,
    linear-gradient(45deg, rgba(232,200,64,.4) 25%, transparent 25%) 0 0 / 40px 40px,
    var(--yellow-pale);
}
.card__thumb--sand {
  background:
    linear-gradient(var(--sand) 1px, transparent 1px) 0 0 / 20px 20px,
    linear-gradient(90deg, var(--sand) 1px, transparent 1px) 0 0 / 20px 20px,
    radial-gradient(circle at 10px 10px, rgba(212,197,176,.5) 4px, transparent 4px) 0 0 / 20px 20px,
    #f0ebe4;
}

.card--featured {
  border-color: rgba(0,0,0,.1);
  position: relative;
}
.card--featured .card__title { font-size: 1.2rem; }

.card__body { padding: 1.25rem 1.5rem; min-width: 0; }
.card--featured .card__body { padding: 1.75rem 2rem; }

.card__meta {
  display: flex;
  align-items: center;
  gap: .6rem;
  margin-bottom: .6rem;
}
.meta-cat { font-size: 0.875rem; color: var(--muted); }
.meta-date { font-size: 0.875rem; color: var(--muted); }
.meta-sep  { color: var(--border); }

.card__title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.7;
  color: var(--fg);
  margin-bottom: .5rem;
  transition: color .2s;
}
.card--featured .card__title { font-size: 1.15rem; }
.card:hover .card__title { color: var(--green-deep); }
.card__title a { color: inherit; text-decoration: none; }
.card__title a::after {
  content: '';
  position: absolute;
  inset: 0;
}

.card__excerpt {
  font-size: 0.875rem;
  line-height: 1.85;
  color: var(--muted);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.card__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 1.25rem;
  flex-wrap: wrap;
  gap: .5rem;
}

/* Tags */
.tags { display: flex; flex-wrap: wrap; gap: .5rem; }
.hashtag { font-size: 0.875rem; color: var(--muted); }
.read-time { font-size: 0.875rem; color: var(--muted); }

/* Category tag badge */
.tag-badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 3px;
  font-size: 0.875rem;
}
.tag-badge--green  { background: rgba(184,212,196,.35); color: var(--fg); }
.tag-badge--yellow { background: rgba(232,200,64,.3);  color: var(--fg); }
.tag-badge--sand   { background: rgba(212,197,176,.4); color: var(--fg); }

/* section-label のタグ用バリエーション（大文字変換なし） */
.section-label--tag { text-transform: none; letter-spacing: normal; }

/* Colored dots */
.dot {
  display: inline-block;
  width: 7px; height: 7px;
  border-radius: 50%;
  flex-shrink: 0;
}
.dot--green  { background: var(--green); }
.dot--yellow { background: var(--yellow); }
.dot--sand   { background: var(--sand); }

/* ===== SIDEBAR ===== */
.sidebar { display: flex; flex-direction: column; gap: 2.5rem; }


.sidebar__section {}
.sidebar__heading {
  font-size: 0.875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: .75rem;
  font-weight: 500;
}

/* Category list */
.cat-list { display: flex; flex-direction: column; gap: .4rem; }
.cat-list__link {
  display: flex;
  align-items: center;
  gap: .5rem;
  justify-content: space-between;
  padding: .5rem 0;
  font-size: 0.875rem;
  color: var(--muted);
  transition: color .2s;
}
.cat-list__link:hover { color: var(--fg); }
.cat-list__link--active { color: var(--green-deep); }
.cat-count {
  font-size: 0.875rem;
  background: var(--section-bg);
  padding: 2px 8px;
  border-radius: 999px;
}

/* Recent list */
.recent-list { display: flex; flex-direction: column; }
.recent-item {
  display: flex;
  gap: .75rem;
  align-items: flex-start;
  padding: .75rem 0;
  border-bottom: 1px solid var(--border);
  transition: opacity .2s;
}
.recent-item:last-child { border-bottom: none; }
.recent-item:hover { opacity: .65; }
.recent-item__bar {
  display: block;
  width: 3px; height: 2.5rem;
  border-radius: 2px;
  flex-shrink: 0;
  margin-top: 2px;
}
.recent-item__bar--green  { background: var(--green); }
.recent-item__bar--yellow { background: var(--yellow); }
.recent-item__bar--sand   { background: var(--sand); }
.recent-item__title {
  font-family: var(--font-heading);
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--fg);
  margin-bottom: .2rem;
}
.recent-item__date { font-size: 0.875rem; color: var(--muted); }

/* Tag cloud */
.tag-cloud { display: flex; flex-wrap: wrap; gap: .5rem; }
.tag-pill {
  font-size: 0.875rem;
  color: var(--muted);
  border: 1px solid var(--border);
  padding: 4px 12px;
  border-radius: 999px;
  transition: color .2s, border-color .2s;
}
.tag-pill:hover { color: var(--green-deep); border-color: var(--green); }

/* ===== FOOTER ===== */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 2.5rem 0;
  margin-top: 4rem;
}
.site-footer .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}
.footer__title {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  letter-spacing: 0.04em;
  margin-bottom: .2rem;
}
.footer__sub { font-size: 0.875rem; color: var(--muted); }
.footer__copy {
  display: flex; align-items: center; gap: .5rem;
  font-size: 0.875rem; color: var(--muted);
}
.footer__dot {
  display: inline-block;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--green);
}

/* ===== BACK TO TOP ===== */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--green);
  color: var(--white);
  border: none;
  font-size: 1.1rem;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: opacity .25s, visibility .25s, background .2s;
  z-index: 100;
}
.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
}
.back-to-top:hover { background: var(--green-deep); }

/* ===== RESPONSIVE ===== */
@media (max-width: 720px) {
  .layout {
    grid-template-columns: 1fr;
  }
  .sidebar { order: -1; }
  .nav { display: none; }
  .nav-toggle { display: flex; }
  .hero__title { font-size: 1.35rem; }
  .card { flex-direction: column; }
  .card__thumb { width: 100%; height: 80px; }
  .card--featured .card__thumb { height: 100px; }
}