/* ============================================================
   データマネジメント入門講座 — Snow Village
   v2: site-design.png 忠実版（毛筆: 花鳥風月）
   ============================================================ */

/* ---------- Font: 花鳥風月（毛筆見出し用） ---------- */
@font-face {
  font-family: "Kachoufuugetsu";
  src: url("fonts/kachoufuugetsu.ttf") format("truetype");
  font-display: swap;
  font-weight: 400;
  font-style: normal;
}

/* ---------- Design Tokens ---------- */
:root {
  --color-bg:        #F6EFE3;  /* Ivory（紙の地色） */
  --color-text:      #2A2118;  /* Espresso */
  --color-text-sub:  #6B5B49;  /* Cocoa */
  --color-divider:   #C9B79C;  /* Sepia line */

  --font-brush: "Kachoufuugetsu", "Yu Mincho", "YuMincho", "Hiragino Mincho ProN", serif;
  --font-body:  "Klee One", "Yu Mincho", "Hiragino Mincho ProN", serif;
  --font-meta:  "Cormorant Garamond", "Times New Roman", serif;

  --content-max: 1344px;  /* Full HD 1920px の約 70% */
}

/* ---------- Reset / Base ---------- */
*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.9;
  letter-spacing: 0.04em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--color-text);
  text-decoration: none;
}
a:focus-visible {
  outline: 2px solid var(--color-text-sub);
  outline-offset: 4px;
  border-radius: 2px;
}

ul, ol { padding: 0; margin: 0; list-style: none; }

h1, h2, h3 { margin: 0; line-height: 1.5; font-weight: 400; }

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

strong { font-weight: 600; }

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0);
  white-space: nowrap; border: 0;
}

.handwritten { mix-blend-mode: multiply; }

.brush-heading {
  font-family: var(--font-brush);
  font-weight: 400;
  letter-spacing: 0.06em;
  color: var(--color-text);
}

/* ---------- Hero（全幅で写真 1 枚） ---------- */
.hero {
  width: 100%;
  margin: 0;
  padding: 0;
}
.hero img {
  width: 100%;
  height: auto;
  display: block;
}

/* ---------- About（入門講座の説明） ---------- */
.about {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: clamp(80px, 12vw, 140px) 24px 0;
  text-align: center;
}
.about-heading {
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  margin-bottom: 56px;
}

.about-frame {
  position: relative;
  max-width: 720px;
  margin: 0 auto;
  padding: 28px clamp(56px, 9vw, 96px);
  /* isolation: isolate を外す。frame-bracket は z-index:-1 で root 文脈に逃がし、
     body の Ivory 背景と multiply 合成させて白を透過させる */
}
.frame-bracket {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: fill;
  pointer-events: none;
  z-index: -1;
}
.about-text {
  text-align: left;
  font-family: var(--font-body);
  font-size: 1.0rem;
  line-height: 2.0;
  color: var(--color-text);
}
.about-text p { margin: 0 0 0.8em; }
.about-text p:last-child { margin-bottom: 0; }

/* ---------- Sessions ---------- */
.sessions {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: clamp(96px, 14vw, 160px) 24px 0;
}
.session-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}
.session {
  display: grid;
  grid-template-columns: 440px 1fr;
  gap: 44px;
  padding: 56px 0;
  border-top: 1px solid var(--color-divider);
}
.session:first-child { border-top: none; padding-top: 8px; }

.session-thumb {
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--color-divider);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}
.session-thumb img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 0.4s ease;
}
a.session-thumb:hover img { transform: scale(1.03); }
a.session-thumb:hover { box-shadow: 0 8px 24px rgba(60, 40, 20, 0.18); }

a.session-thumb[aria-disabled="true"] {
  pointer-events: none;
  cursor: not-allowed;
}

.session-thumb-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  background:
    radial-gradient(ellipse at 30% 30%, rgba(255,255,255,0.5), transparent 70%),
    linear-gradient(135deg, #EFE2C7 0%, #D9C7AB 100%);
}

/* Thumb overlay: dark gradient + white text on top of image */
.session-thumb-overlay { position: relative; }
.session-thumb-overlay img { width: 100%; height: 100%; object-fit: cover; }
.session-thumb-overlay::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(20, 14, 8, 0.35) 0%, rgba(20, 14, 8, 0.72) 100%);
  pointer-events: none;
  z-index: 1;
}
.thumb-overlay-text {
  position: absolute;
  inset: 0;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #FFFFFF;
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.55);
  padding: 20px;
  line-height: 1.65;
}
.session-thumb-overlay--cta .thumb-overlay-text {
  font-family: var(--font-brush);
  font-size: clamp(1.35rem, 2.2vw, 1.85rem);
  letter-spacing: 0.08em;
}
.session-thumb-overlay--coming .thumb-overlay-text {
  font-family: var(--font-meta);
  font-style: italic;
  font-weight: 500;
  font-size: clamp(1.9rem, 3vw, 2.6rem);
  letter-spacing: 0.18em;
}
.session-thumb-placeholder::before {
  content: "Ep. " attr(data-episode);
  font-family: var(--font-meta);
  font-style: italic;
  font-size: clamp(2.4rem, 5vw, 3.2rem);
  color: var(--color-text-sub);
  opacity: 0.7;
  letter-spacing: 0.04em;
}

.session-body {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 4px 0;
}
.session-title {
  font-size: clamp(1.7rem, 3vw, 2.4rem);
  margin-bottom: 18px;
  line-height: 1.5;
}
.session-speaker {
  font-size: 0.9rem;
  color: var(--color-text-sub);
  margin: 0 0 14px;
}
.session-desc {
  font-size: 0.98rem;
  color: var(--color-text);
  line-height: 1.95;
  margin: 0 0 auto;
}
.session-desc.is-placeholder {
  color: var(--color-text-sub);
  font-style: italic;
  opacity: 0.55;
}

.session-links {
  display: flex;
  align-items: baseline;
  justify-content: flex-end;
  gap: clamp(12px, 2.4vw, 24px);
  margin-top: 24px;
}
.link-label {
  display: inline-flex;
  align-items: center;
}
.link-label img {
  height: 64px;
  width: auto;
  mix-blend-mode: multiply;
  transition: transform 0.2s ease;
}
.link-label:hover img { transform: rotate(-1.5deg) scale(1.04); }
.link-label[aria-disabled="true"] {
  pointer-events: none;
  cursor: not-allowed;
}
.link-label[aria-disabled="true"] img {
  opacity: 0.3;
  filter: grayscale(0.6);
}

@media (max-width: 720px) {
  .session {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 28px 0;
  }
  .session-thumb { aspect-ratio: 16 / 9; }
  .session-links { gap: 14px; }
  .link-label img { height: 48px; }
}

/* ---------- Footer ---------- */
.site-footer {
  margin-top: clamp(48px, 8vw, 80px);
  padding: 32px 24px 64px;
  text-align: center;
}
.site-footer p { margin: 0; }
.footer-brand {
  font-family: var(--font-brush);
  font-weight: 400;
  font-size: clamp(1.2rem, 2vw, 1.6rem);
  color: var(--color-text);
  letter-spacing: 0.1em;
}

/* ---------- Shared: info-card content (used by floating + bottom panels) ---------- */
.info-eyebrow {
  font-family: var(--font-brush);
  font-weight: 400;
  font-size: 1.15rem;
  color: var(--color-text);
  letter-spacing: 0.08em;
  margin: 0 0 8px;
}
.info-card p { margin: 0 0 8px; line-height: 1.75; }
.info-card p:last-child { margin-bottom: 0; }
.info-card a {
  color: var(--color-text);
  text-decoration: underline;
  text-decoration-color: var(--color-text-sub);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}
.info-card a:hover { color: var(--color-text-sub); }
.info-card code {
  font-family: ui-monospace, "SFMono-Regular", Consolas, monospace;
  font-size: 0.9em;
  background: var(--color-bg);
  padding: 0.05em 0.4em;
  border-radius: 3px;
}
.info-card strong { font-weight: 600; }

/* ---------- Floating panel (PC のみ表示) ---------- */
.floating-panel {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 340px;
  max-width: calc(100vw - 48px);
  background: #FBF7EE;
  border: 1px solid var(--color-divider);
  border-radius: 14px;
  padding: 18px 20px;
  box-shadow: 0 12px 28px rgba(60, 40, 20, 0.18);
  font-size: 0.82rem;
  line-height: 1.75;
  z-index: 100;
}
.floating-panel .info-eyebrow { font-size: 1.05rem; }
.floating-panel .info-card + .info-card {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px dashed var(--color-divider);
}

@media (max-width: 720px) {
  .floating-panel { display: none; }
}

/* ---------- Bottom info（最下部・常時表示） ---------- */
.bottom-info {
  max-width: var(--content-max);
  margin: clamp(96px, 14vw, 160px) auto 0;
  padding: 0 24px;
}
.bottom-info-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(32px, 5vw, 64px);
}
.bottom-info .info-card {
  font-size: 0.95rem;
}
@media (max-width: 720px) {
  .bottom-info-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .bottom-info .info-card + .info-card {
    padding-top: 28px;
    border-top: 1px dashed var(--color-divider);
  }
}

/* ---------- Motion preferences ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition: none !important;
    animation: none !important;
    scroll-behavior: auto !important;
  }
}

/* ---------- About frame: モバイルでは枠を隠す ---------- */
@media (max-width: 560px) {
  .about-frame { padding: 16px 8px; }
  .frame-bracket { display: none; }
}