/* 边学边玩 Hub — 视觉 v2A 贴纸徽章（Scrapbook Stickers）
   CSS-only；保留原有 class / SEO 骨架。
   签名：白纸底 + 黑描边贴纸卡 + 柠檬主 CTA / 莓红强调。不用奶油珊瑚。 */

:root {
  --bg: #fafaf7;
  --surface: #ffffff;
  --text: #1c1917;
  --muted: #57534e;
  --ink: #1c1917;
  --border: #1c1917;
  --brand: #f5e74e;          /* 柠檬贴 */
  --brand-ink: #1c1917;
  --berry: #e11d48;          /* 莓红贴 */
  --berry-soft: #ffe4e9;
  --teal: #0d9488;           /* 青绿贴 */
  --teal-soft: #ccfbf1;
  --lemon-soft: #fef9c3;
  --warn-bg: #fff7ed;
  --warn-border: #1c1917;
  --radius: 0.75rem;
  --radius-lg: 1rem;
  --tap: 2.85rem;
  --max: 42rem;
  --max-wide: 58rem;
  --shadow-sticker: 4px 4px 0 var(--ink);
  --shadow-sticker-hover: 6px 6px 0 var(--ink);
  --font: "Fredoka", "ZCOOL KuaiLe", system-ui, -apple-system, "Segoe UI",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--text);
  background-color: var(--bg);
  background-image:
    radial-gradient(circle at 1px 1px, rgba(28, 25, 23, 0.06) 1px, transparent 0);
  background-size: 18px 18px;
}

a { color: var(--berry); }
a:hover { color: #be123c; }
img { max-width: 100%; height: auto; }
code {
  font-size: 0.92em;
  background: var(--lemon-soft);
  border: 1.5px solid var(--ink);
  padding: 0.1em 0.4em;
  border-radius: 0.35rem;
}

/* —— Header：白底厚描边 —— */
.site-header {
  background: var(--surface);
  border-bottom: 3px solid var(--ink);
  position: sticky;
  top: 0;
  z-index: 20;
}
.site-header-inner {
  max-width: var(--max-wide);
  margin: 0 auto;
  padding: 0.85rem 1.15rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.65rem 1.25rem;
  justify-content: space-between;
}
.brand-lockup {
  display: flex;
  flex-direction: column;
  gap: 0.05rem;
  text-decoration: none;
  color: inherit;
}
.brand-lockup .name {
  font-weight: 800;
  font-size: 1.28rem;
  letter-spacing: 0.01em;
  color: var(--ink);
}
.brand-lockup .tag {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--muted);
}
.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem 0.45rem;
  align-items: center;
  font-size: 0.95rem;
}
.nav a {
  text-decoration: none;
  color: var(--muted);
  font-weight: 700;
  padding: 0.35rem 0.7rem;
  border-radius: var(--radius);
  border: 2px solid transparent;
}
.nav a:hover {
  color: var(--ink);
  background: var(--lemon-soft);
  border-color: var(--ink);
}
.nav a[aria-current="page"] {
  color: #fff;
  background: var(--berry);
  border-color: var(--ink);
}
.lang-switch {
  display: inline-flex;
  border: 2px solid var(--ink);
  border-radius: var(--radius);
  overflow: hidden;
  font-size: 0.8rem;
  margin-left: 0.25rem;
}
.lang-switch a {
  padding: 0.3rem 0.7rem;
  text-decoration: none;
  color: var(--muted);
  background: var(--surface);
  font-weight: 700;
  border-radius: 0;
  border: none;
}
.lang-switch a[aria-current="true"] {
  background: var(--brand);
  color: var(--ink);
}

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 1.5rem 1.15rem 2.75rem;
}
.wrap-wide {
  max-width: var(--max-wide);
  margin: 0 auto;
  padding: 1.5rem 1.15rem 2.75rem;
}

/* —— Hero：贴纸大卡 —— */
.hero {
  background: var(--surface);
  border: 3px solid var(--ink);
  border-radius: var(--radius-lg);
  padding: 1.65rem 1.45rem 1.75rem;
  box-shadow: var(--shadow-sticker);
  margin-bottom: 1.85rem;
  position: relative;
}
.hero::before {
  content: "PLAY";
  position: absolute;
  top: -0.7rem;
  right: 1.1rem;
  background: var(--brand);
  color: var(--ink);
  border: 2px solid var(--ink);
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  padding: 0.2rem 0.65rem;
  box-shadow: 2px 2px 0 var(--ink);
}
.hero h1 {
  font-size: clamp(1.5rem, 4vw, 2rem);
  line-height: 1.28;
  margin: 0 0 0.7rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}
.hero .lede {
  margin: 0;
  color: var(--muted);
  font-size: 1.06rem;
  font-weight: 600;
}
.hero .pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 1.15rem;
}
.pill {
  display: inline-block;
  font-size: 0.82rem;
  font-weight: 800;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius);
  background: var(--lemon-soft);
  border: 2px solid var(--ink);
  color: var(--ink);
  box-shadow: 2px 2px 0 var(--ink);
}

h1.page-title {
  font-size: clamp(1.4rem, 3.5vw, 1.8rem);
  line-height: 1.3;
  margin: 0 0 0.55rem;
  font-weight: 800;
}
h2 {
  font-size: 1.28rem;
  margin: 1.85rem 0 0.65rem;
  font-weight: 800;
  color: var(--text);
}
.meta {
  color: var(--muted);
  font-size: 1rem;
  margin: 0 0 1.1rem;
  font-weight: 600;
}
.clarify {
  background: var(--teal-soft);
  border: 3px solid var(--ink);
  border-left: 10px solid var(--teal);
  padding: 1rem 1.15rem;
  margin: 1.15rem 0 1.5rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sticker);
  font-weight: 600;
}
.todo {
  background: var(--warn-bg);
  border: 3px solid var(--ink);
  padding: 0.95rem 1.1rem;
  border-radius: var(--radius);
  font-size: 0.98rem;
  box-shadow: 3px 3px 0 var(--ink);
}
.todo strong { display: block; margin-bottom: 0.3rem; font-weight: 800; }

/* —— 学科贴纸卡 —— */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 1.25rem;
  margin: 1.25rem 0 1.85rem;
}
.card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 3px solid var(--ink);
  border-radius: var(--radius-lg);
  padding: 1.3rem 1.15rem 1.25rem;
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow-sticker);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
  min-height: 11rem;
}
.card:hover {
  transform: translate(-2px, -2px) rotate(-0.6deg);
  box-shadow: var(--shadow-sticker-hover);
  color: inherit;
}
.card .emoji {
  font-size: 2.2rem;
  margin-bottom: 0.4rem;
  line-height: 1;
}
.card h2 {
  margin: 0 0 0.35rem;
  font-size: 1.18rem;
  color: var(--text);
}
.card p {
  margin: 0;
  flex: 1;
  font-size: 0.98rem;
  color: var(--muted);
  font-weight: 600;
}
.card .more {
  margin-top: 1rem;
  font-size: 0.95rem;
  font-weight: 800;
  color: #9f1239; /* 加深：粉洗底上对比更稳 */
  text-decoration: underline;
  text-underline-offset: 0.18em;
}

.card-grid .card:nth-child(1) { background: linear-gradient(180deg, #fff 70%, var(--berry-soft) 100%); }
.card-grid .card:nth-child(2) { background: linear-gradient(180deg, #fff 70%, var(--teal-soft) 100%); }
.card-grid .card:nth-child(2) .more { color: #115e59; }
.card-grid .card:nth-child(3) { background: linear-gradient(180deg, #fff 70%, var(--lemon-soft) 100%); }
.card-grid .card:nth-child(3) .more { color: #854d0e; }

/* —— CTA：矩形徽章，非胶囊 —— */
.cta-row { margin: 1.35rem 0 0.55rem; }
.cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: var(--tap);
  margin: 0.35rem 0.5rem 0.35rem 0;
  padding: 0.7rem 1.25rem;
  background: var(--brand);
  color: var(--brand-ink) !important;
  text-decoration: none;
  border-radius: var(--radius);
  font-weight: 800;
  font-size: 1.02rem;
  border: 3px solid var(--ink);
  box-shadow: var(--shadow-sticker);
  transition: transform 0.1s ease, box-shadow 0.1s ease;
}
.cta:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-sticker-hover);
}
.cta:active {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 var(--ink);
}
.cta.secondary {
  background: #fff;
  color: var(--ink) !important;
}
.cta.ghost {
  background: var(--bg);
  color: var(--muted) !important;
  box-shadow: 3px 3px 0 #a8a29e;
}

.note {
  font-size: 0.9rem;
  color: var(--muted);
  margin-top: 0.95rem;
  font-weight: 600;
}

.faq-list { margin: 0; padding: 0; list-style: none; }
.faq-list li {
  background: var(--surface);
  border: 3px solid var(--ink);
  border-radius: var(--radius);
  padding: 1rem 1.15rem;
  margin-bottom: 0.75rem;
  box-shadow: 3px 3px 0 var(--ink);
}
.faq-list strong {
  display: block;
  margin-bottom: 0.3rem;
  font-weight: 800;
  font-size: 1.05rem;
}

.site-footer {
  border-top: 3px solid var(--ink);
  background: var(--surface);
  margin-top: 2.25rem;
}
.site-footer-inner {
  max-width: var(--max-wide);
  margin: 0 auto;
  padding: 1.45rem 1.15rem 1.85rem;
  font-size: 0.9rem;
  color: var(--muted);
  font-weight: 600;
}
.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 0.75rem;
  margin-bottom: 0.75rem;
}
.site-footer a {
  color: var(--berry);
  text-decoration: none;
  font-weight: 700;
}
.site-footer a:hover { text-decoration: underline; }
.disclaimer {
  font-size: 0.84rem;
  line-height: 1.55;
  margin: 0.55rem 0 0;
  font-weight: 560;
}

.wrap > h1.page-title::before {
  content: "★ ";
  color: var(--berry);
  font-weight: 800;
}

@media (max-width: 560px) {
  .site-header-inner { align-items: flex-start; }
  .hero { padding: 1.35rem 1.1rem 1.5rem; }
  .hero::before { right: 0.75rem; }
  .cta { width: 100%; margin-right: 0; }
  body { font-size: 1.02rem; }
}

@media (prefers-reduced-motion: reduce) {
  .card, .cta { transition: none; }
  .card:hover { transform: none; }
}