/* ============================================================
   b次元追漫盒子官网 - 漫画杂志纸感主题（暖黄 × 墨黑）
   bciyuan.net.cn
   ============================================================ */

/* ---------- 设计变量 ---------- */
:root {
  --bg: #fdf8ec;
  --bg-alt: #fff3d6;
  --surface: #ffffff;
  --surface-2: #ffe9b8;
  --ink: #1a1410;
  --line: rgba(26, 20, 16, 0.14);
  --line-strong: rgba(26, 20, 16, 0.32);
  --text: #241d16;
  --muted: #7a6f61;
  --accent: #ffb800;
  --accent-2: #ff7a00;
  --gold: #ff7a00;
  --grad: linear-gradient(120deg, #ffc81c 0%, #ff9500 100%);
  --radius-lg: 18px;
  --radius-md: 12px;
  --shadow-card: 6px 6px 0 rgba(26, 20, 16, 0.14);
  --font: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Source Han Sans SC", sans-serif;
}

/* ---------- 基础 ---------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  overflow-x: hidden;
}

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

a {
  color: var(--accent-2);
  text-decoration: none;
}

ul,
ol {
  list-style: none;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 999;
  background: var(--ink);
  color: #fff;
  padding: 10px 18px;
  border-radius: 0 0 10px 0;
}

.skip-link:focus {
  left: 0;
}

.container {
  width: min(1120px, 92%);
  margin: 0 auto;
}

/* 漫画网点装饰 */
.dots {
  background-image: radial-gradient(rgba(26, 20, 16, 0.16) 1.4px, transparent 1.4px);
  background-size: 14px 14px;
}

/* ---------- 通用标题 ---------- */
.eyebrow {
  font-size: 12px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--accent-2);
  margin-bottom: 14px;
  font-weight: 700;
}

.section {
  padding: 72px 0;
}

.section-alt {
  background: var(--bg-alt);
}

.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 46px;
}

.section-head h2 {
  font-size: clamp(26px, 4.6vw, 36px);
  line-height: 1.3;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.section-desc {
  color: var(--muted);
  margin-top: 12px;
  font-size: 15px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 34px;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.04em;
  border: 2px solid var(--ink);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
  min-height: 48px;
}

.btn:active {
  transform: scale(0.97) translate(2px, 2px);
  box-shadow: none;
}

.btn-primary {
  background: var(--ink);
  color: #ffd76a;
  box-shadow: 5px 5px 0 rgba(255, 149, 0, 0.55);
}

.btn-primary:hover {
  transform: translateY(-2px);
  background: #241d16;
  box-shadow: 7px 7px 0 rgba(255, 149, 0, 0.55);
}

.btn-ghost {
  background: var(--surface);
  color: var(--ink);
  box-shadow: 5px 5px 0 rgba(26, 20, 16, 0.16);
}

.btn-ghost:hover {
  background: var(--surface-2);
}

.btn-light {
  background: #ffd76a;
  color: var(--ink);
  box-shadow: 5px 5px 0 rgba(26, 20, 16, 0.35);
}

.btn-light:hover {
  transform: translateY(-2px);
  background: #ffe194;
}

.btn-lg {
  padding: 18px 54px;
  font-size: 18px;
}

/* ---------- 头部导航 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(253, 248, 236, 0.86);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 2px solid transparent;
  transition: background 0.3s ease, border-color 0.3s ease;
}

.site-header.is-scrolled {
  background: rgba(253, 248, 236, 0.97);
  border-bottom-color: var(--line);
}

.header-inner {
  width: min(1120px, 92%);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.brand-icon {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  object-fit: cover;
  border: 2px solid var(--ink);
}

.brand-name {
  font-size: 19px;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 26px;
}

.main-nav > a:not(.btn-download) {
  color: var(--text);
  font-size: 15px;
  font-weight: 600;
  opacity: 0.88;
  transition: opacity 0.2s ease, color 0.2s ease;
}

.main-nav > a:not(.btn-download):hover {
  opacity: 1;
  color: var(--accent-2);
}

.btn-download {
  padding: 10px 22px;
  border-radius: 10px;
  background: var(--ink);
  color: #ffd76a !important;
  font-weight: 800;
  font-size: 14px;
  border: 2px solid var(--ink);
  box-shadow: 4px 4px 0 rgba(255, 149, 0, 0.5);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  opacity: 1 !important;
}

.btn-download:hover {
  transform: translateY(-1px);
  box-shadow: 6px 6px 0 rgba(255, 149, 0, 0.5);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: transparent;
  border: 0;
  cursor: pointer;
  padding: 10px;
}

.nav-toggle .bar {
  display: block;
  width: 22px;
  height: 3px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-toggle.is-active .bar:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.nav-toggle.is-active .bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle.is-active .bar:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 94vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 0 80px;
  text-align: center;
  overflow: hidden;
  background:
    radial-gradient(ellipse at 16% 22%, rgba(255, 184, 0, 0.28), transparent 46%),
    radial-gradient(ellipse at 84% 20%, rgba(255, 122, 0, 0.2), transparent 46%),
    linear-gradient(180deg, #fff9ea 0%, #fdf8ec 100%);
}

.hero-dots {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(26, 20, 16, 0.1) 1.4px, transparent 1.4px);
  background-size: 16px 16px;
  z-index: 0;
}

.hero-inner {
  position: relative;
  z-index: 1;
  width: min(840px, 92%);
}

.hero-icon {
  width: 92px;
  height: 92px;
  border-radius: 20px;
  margin: 0 auto 24px;
  border: 3px solid var(--ink);
  box-shadow: 6px 6px 0 rgba(26, 20, 16, 0.22);
}

.hero-title {
  font-size: clamp(46px, 9.6vw, 84px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: 0.06em;
  color: var(--ink);
  margin-bottom: 22px;
}

.hero-title .hl {
  background: linear-gradient(120deg, #ffc81c, #ff9500);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-sub {
  color: #5f5344;
  font-size: clamp(15px, 2.4vw, 18px);
  max-width: 600px;
  margin: 0 auto 34px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: clamp(28px, 7vw, 72px);
  margin-top: 54px;
  flex-wrap: wrap;
}

.stat dt {
  font-size: clamp(26px, 4.6vw, 38px);
  font-weight: 900;
  color: var(--accent-2);
  letter-spacing: 0.03em;
}

.stat dd {
  font-size: 13px;
  color: var(--muted);
  margin-top: 2px;
  letter-spacing: 0.1em;
}

/* ---------- 功能介绍 ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
}

.feature-card {
  background: var(--surface);
  border: 2px solid var(--ink);
  border-radius: var(--radius-lg);
  padding: 18px 18px 24px;
  box-shadow: var(--shadow-card);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.feature-card:hover {
  transform: translate(-2px, -3px);
  box-shadow: 9px 9px 0 rgba(26, 20, 16, 0.16);
}

.feature-shot {
  border-radius: 10px;
  overflow: hidden;
  margin-bottom: 16px;
  aspect-ratio: 4 / 5;
  background: var(--bg-alt);
  border: 1px solid var(--ink);
}

.feature-shot img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  transition: transform 0.4s ease;
}

.feature-card:hover .feature-shot img {
  transform: scale(1.05);
}

.feature-card h3 {
  font-size: 19px;
  margin-bottom: 8px;
  letter-spacing: 0.02em;
  color: var(--ink);
  display: inline-block;
  padding: 0 6px;
  background: linear-gradient(transparent 62%, rgba(255, 184, 0, 0.65) 62%);
}

.feature-card p {
  font-size: 14px;
  color: var(--muted);
}

/* ---------- 人气榜 ---------- */
.rank-wrap {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  align-items: start;
}

.rank-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.rank-list li {
  display: flex;
  align-items: center;
  gap: 18px;
  background: var(--surface);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  box-shadow: 4px 4px 0 rgba(26, 20, 16, 0.12);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.rank-list li:hover {
  transform: translateX(4px);
}

.rank-no {
  font-size: 24px;
  font-weight: 900;
  color: var(--accent-2);
  font-style: italic;
  letter-spacing: 0.02em;
  width: 40px;
}

.rank-info {
  flex: 1;
  min-width: 0;
}

.rank-info h3 {
  font-size: 17px;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.rank-info p {
  font-size: 13px;
  color: var(--muted);
  margin-top: 2px;
}

.rank-heat {
  color: var(--accent-2);
  font-weight: 800;
  font-size: 15px;
}

.rank-quote {
  background:
    radial-gradient(ellipse at 80% 0%, rgba(255, 184, 0, 0.28), transparent 60%),
    radial-gradient(ellipse at 10% 100%, rgba(255, 122, 0, 0.2), transparent 60%),
    var(--surface);
  border: 2px solid var(--ink);
  border-radius: var(--radius-lg);
  padding: 30px 26px;
  text-align: center;
  box-shadow: 6px 6px 0 rgba(26, 20, 16, 0.14);
}

.quote-img {
  width: 88px;
  height: 88px;
  border-radius: 20px;
  object-fit: cover;
  margin: 0 auto 18px;
  border: 2px solid var(--ink);
  box-shadow: 5px 5px 0 rgba(255, 149, 0, 0.5);
}

.rank-quote blockquote {
  font-size: 15px;
  color: var(--text);
  line-height: 1.9;
  margin-bottom: 8px;
}

.rank-quote cite {
  display: block;
  font-style: normal;
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 22px;
}

/* ---------- 次元分类 ---------- */
.cat-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}

.cat-item {
  background: var(--surface);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  box-shadow: 4px 4px 0 rgba(26, 20, 16, 0.1);
  transition: border-color 0.2s ease, background 0.2s ease, transform 0.2s ease;
}

.cat-item:hover {
  background: var(--surface-2);
  transform: translate(-1px, -2px);
}

.cat-icon {
  width: 30px;
  height: 30px;
  color: var(--accent-2);
  margin-bottom: 6px;
}

.cat-item h3 {
  font-size: 17px;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.cat-item p {
  font-size: 13.5px;
  color: var(--muted);
}

/* ---------- 更新手记 ---------- */
.note-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
  max-width: 720px;
  margin: 0 auto;
}

.note-list li {
  display: flex;
  gap: 20px;
  background: var(--surface);
  border: 2px solid var(--ink);
  border-radius: var(--radius-md);
  padding: 20px 22px;
  box-shadow: 4px 4px 0 rgba(26, 20, 16, 0.1);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.note-list li:hover {
  transform: translateY(-3px);
  box-shadow: 7px 7px 0 rgba(26, 20, 16, 0.12);
}

.note-list time {
  flex: 0 0 auto;
  align-self: flex-start;
  font-weight: 900;
  color: var(--ink);
  font-size: 15px;
  padding: 4px 12px;
  background: var(--grad);
  border: 2px solid var(--ink);
  border-radius: 8px;
  letter-spacing: 0.04em;
  margin-top: 2px;
}

.note-body h3 {
  font-size: 17px;
  margin-bottom: 6px;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.note-body p {
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 8px;
}

.note-body a {
  font-size: 14px;
  font-weight: 700;
}

.note-body a:hover {
  text-decoration: underline;
}

/* ---------- 关于 b次元 ---------- */
.about {
  background:
    radial-gradient(ellipse at 18% 24%, rgba(255, 184, 0, 0.22), transparent 48%),
    radial-gradient(ellipse at 82% 72%, rgba(255, 122, 0, 0.16), transparent 48%),
    var(--bg);
  position: relative;
}

.about-dots {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(26, 20, 16, 0.08) 1.4px, transparent 1.4px);
  background-size: 18px 18px;
  z-index: 0;
}

.about-inner {
  position: relative;
  z-index: 1;
  width: min(760px, 92%);
  margin: 0 auto;
  text-align: center;
}

.about-inner h2 {
  font-size: clamp(28px, 5.2vw, 42px);
  line-height: 1.35;
  letter-spacing: 0.03em;
  color: var(--ink);
  margin-bottom: 20px;
}

.about-text {
  color: #5f5344;
  font-size: 15.5px;
  max-width: 600px;
  margin: 0 auto 30px;
}

.about-points {
  display: flex;
  flex-direction: column;
  gap: 10px;
  align-items: center;
  color: var(--muted);
  font-size: 14.5px;
}

.about-points li {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.about-points li::before {
  content: "";
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--grad);
  border: 1px solid var(--ink);
  flex: 0 0 auto;
}

/* ---------- 下载 ---------- */
.cta {
  padding: 60px 0;
}

.cta-card {
  position: relative;
  overflow: hidden;
  text-align: center;
  background:
    radial-gradient(ellipse at 50% 0%, rgba(255, 200, 28, 0.24), transparent 60%),
    var(--ink);
  border: 2px solid var(--ink);
  border-radius: 22px;
  padding: 64px 24px;
  box-shadow: 8px 8px 0 rgba(255, 149, 0, 0.4);
  color: #fff6e0;
}

.cta-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(255, 215, 106, 0.14) 1.4px, transparent 1.4px);
  background-size: 16px 16px;
}

.cta-card > * {
  position: relative;
  z-index: 1;
}

.cta-card .eyebrow {
  color: #ffd76a;
}

.cta-card h2 {
  font-size: clamp(26px, 4.8vw, 38px);
  margin-bottom: 14px;
  letter-spacing: 0.02em;
  color: #fff6e0;
}

.cta-desc {
  color: rgba(255, 246, 224, 0.85);
  max-width: 520px;
  margin: 0 auto 30px;
  font-size: 15px;
}

.cta-note {
  margin-top: 20px;
  font-size: 13px;
  color: rgba(255, 246, 224, 0.82);
  letter-spacing: 0.04em;
}

/* ---------- 页脚 ---------- */
.site-footer {
  background: #1a1410;
  color: #f3e9d8;
  padding: 48px 0 36px;
}

.footer-inner {
  width: min(1120px, 92%);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 26px;
  align-items: flex-start;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.footer-brand .brand-icon {
  width: 34px;
  height: 34px;
  border-color: #f3e9d8;
}

.footer-brand strong {
  font-size: 18px;
  letter-spacing: 0.04em;
  color: #fff6e0;
}

.footer-brand p {
  display: none;
}

.footer-nav {
  display: flex;
  gap: 22px;
  flex-wrap: wrap;
}

.footer-nav a {
  color: rgba(243, 233, 216, 0.7);
  font-size: 14px;
  transition: color 0.2s ease;
}

.footer-nav a:hover {
  color: #ffd76a;
}

.footer-meta a {
  color: rgba(243, 233, 216, 0.7);
  font-size: 14px;
}

.footer-meta a:hover {
  color: #ffd76a;
}

.footer-meta p {
  color: rgba(243, 233, 216, 0.55);
  font-size: 12.5px;
  margin-top: 4px;
}

/* ---------- 回到顶部 ---------- */
.back-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  width: 48px;
  height: 48px;
  border-radius: 12px;
  border: 2px solid var(--ink);
  background: var(--accent);
  color: var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease, box-shadow 0.3s ease;
  z-index: 90;
  box-shadow: 4px 4px 0 rgba(26, 20, 16, 0.25);
}

.back-top svg {
  width: 20px;
  height: 20px;
}

.back-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-top:hover {
  box-shadow: 6px 6px 0 rgba(26, 20, 16, 0.25);
}

/* ---------- 响应式 ---------- */
@media (min-width: 960px) {
  .feature-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .rank-wrap {
    grid-template-columns: 1.4fr 1fr;
  }

  .cat-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .note-list {
    max-width: 860px;
  }

  .about-points {
    flex-direction: row;
    justify-content: center;
    gap: 34px;
  }

  .footer-inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
  }

  .footer-brand p {
    display: block;
    font-size: 13px;
    color: rgba(243, 233, 216, 0.6);
  }

  .footer-brand {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
}

@media (min-width: 640px) and (max-width: 959px) {
  .cat-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .main-nav {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    background: rgba(253, 248, 236, 0.98);
    border-bottom: 2px solid var(--line);
    padding: 10px 5vw 18px;
    display: none;
  }

  .main-nav.is-open {
    display: flex;
  }

  .main-nav > a {
    padding: 12px 6px;
  }

  .btn-download {
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }
}