/* ===== FONTS (self-hosted, latin subset — CJK 由系统字体兜底) ===== */
@font-face{font-family:'HarmonyOS Sans';font-style:normal;font-weight:400;font-display:swap;src:local('HarmonyOS Sans'),url('../fonts/harmonyos-sans-400.woff2') format('woff2')}
@font-face{font-family:'HarmonyOS Sans';font-style:normal;font-weight:500;font-display:swap;src:local('HarmonyOS Sans'),url('../fonts/harmonyos-sans-500.woff2') format('woff2')}
@font-face{font-family:'HarmonyOS Sans';font-style:normal;font-weight:700;font-display:swap;src:local('HarmonyOS Sans'),url('../fonts/harmonyos-sans-700.woff2') format('woff2')}
@font-face{font-family:'HarmonyOS Sans';font-style:normal;font-weight:900;font-display:swap;src:local('HarmonyOS Sans'),url('../fonts/harmonyos-sans-900.woff2') format('woff2')}

*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
:root{
  --primary:#40A8C4;
  --primary-hover:#3590A8;
  --text:#1a1a1a;
  --text-secondary:#555;
  --bg:#fff;
  --bg-light:#f8f8f8;
  --card-bg:#fdf5ec;
  --border:#e5e5e5;
  --header-bg:rgba(255,255,255,.92);
  --radius:12px;
  --radius-lg:20px;
  --max-w:1200px;
  --font-sans:'HarmonyOS Sans',-apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
}
/* 深浅主题完全跟随操作系统：没有切换按钮，也不读写任何本地偏好。
   全部深色规则都写在这个媒体查询里，别再引入 [data-theme] 之类的手动开关。 */
@media(prefers-color-scheme:dark){
  :root{
    --text:#e8e8e8;
    --text-secondary:#aaa;
    --bg:#111;
    --bg-light:#1a1a1a;
    --card-bg:#1e1e1e;
    --border:#333;
    --header-bg:rgba(17,17,17,.92);
    --primary:#5BBDD4;
    --primary-hover:#4AACC4;
  }
}
html{scroll-behavior:smooth;font-size:16px}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation-duration:0.01ms!important;transition-duration:0.01ms!important}}
body{font-family:var(--font-sans);font-weight:400;color:var(--text);background:var(--bg);line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:hidden}
a{text-decoration:none;color:inherit}
/* height:auto 让 img 的 width/height 属性只提供宽高比（用于占位、防止 CLS），
   实际高度仍由 CSS 决定；需要固定高度的规则各自显式声明 */
img{max-width:100%;height:auto;display:block}
h1,h2,h3{font-weight:700}
.container{max-width:var(--max-w);margin:0 auto;padding:0 24px}

/* ===== INLINE SVG ICONS ===== */
/* 内联 <svg> 的 width:auto 会被解析为 100%，必须显式给宽度。
   宽度 = viewBox 宽 / 512，与 Font Awesome 的字形步进一致 */
.svg-sprite{display:none}
.icon{height:1em;width:1em;fill:currentColor;display:inline-block;vertical-align:-.125em;flex-shrink:0}
.icon-w75{width:.75em}
.icon-w88{width:.875em}
.icon-w97{width:.96875em}
.icon-w113{width:1.125em}
.icon-w125{width:1.25em}

/* ===== HEADER ===== */
header{position:sticky;top:0;z-index:100;background:var(--header-bg);backdrop-filter:blur(12px);border-bottom:1px solid var(--border)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.logo{display:flex;align-items:center}
.logo img{height:30px;width:auto}
.header-right{display:flex;align-items:center;gap:24px}
.nav-links{display:flex;gap:32px;align-items:center}
/* 一律用直接子选择器 .nav-links>a：语言下拉里的每一项现在也是 <a>，
   但它嵌在 .nav-actions 里，不该套用导航项的字号、下划线和移动端分隔线 */
.nav-links>a{font-size:.95rem;font-weight:500;color:var(--text-secondary);transition:color .2s;position:relative}
.nav-links>a:hover,.nav-links>a.active{color:var(--text)}
.nav-links>a.active::after{content:'';position:absolute;bottom:-4px;left:0;right:0;height:2px;background:var(--primary);border-radius:1px}
.nav-actions{display:flex;align-items:center;gap:16px}
.nav-actions .nav-icon{font-size:1.15rem;color:var(--text-secondary);transition:color .2s}
.nav-actions .nav-icon:hover{color:var(--text)}
.nav-actions .lang-toggle{padding:0;font-size:1.05rem;background:none;border:none;cursor:pointer;color:var(--text-secondary);transition:color .2s;line-height:1}
.nav-actions .lang-toggle:hover{color:var(--text)}
.lang-wrapper{position:relative}
.lang-dropdown{position:absolute;top:calc(100% + 8px);right:0;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);padding:4px;box-shadow:0 8px 24px rgba(0,0,0,.1);opacity:0;visibility:hidden;transform:translateY(4px);transition:opacity .2s,visibility .2s,transform .2s;z-index:50;min-width:120px}
.lang-dropdown.open{opacity:1;visibility:visible;transform:translateY(0)}
.lang-option{display:block;width:100%;padding:8px 16px;background:none;border:none;cursor:pointer;font-size:.85rem;font-weight:500;color:var(--text-secondary);text-align:left;white-space:nowrap;border-radius:8px;transition:background .15s,color .15s;font-family:var(--font-sans)}
.lang-option:hover{background:var(--bg-light);color:var(--text)}
.lang-option.active{color:var(--text);font-weight:700}
.hamburger{display:none;background:none;border:none;cursor:pointer;padding:4px;flex-direction:column;gap:5px}
.hamburger span{display:block;width:22px;height:2px;background:var(--text);border-radius:2px;transition:transform .3s,opacity .3s}
.hamburger.active span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.hamburger.active span:nth-child(2){opacity:0}
.hamburger.active span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* ===== HERO ===== */
.hero{padding:80px 0 60px;position:relative;overflow:visible}
.hero-grid{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center}
.hero-text{position:relative}
.hero-text h1{font-size:2.8rem;line-height:1.3;font-weight:900;margin-bottom:16px}
.hero-text h1.doodle{position:relative;display:inline-block;z-index:1}
.hero-text h1.doodle::before{content:'';position:absolute;right:0;bottom:2%;width:35%;height:35%;background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 300 60'%3E%3Cellipse cx='150' cy='30' rx='145' ry='22' fill='%2340A8C4' opacity='.45' transform='rotate(-3 150 30)'/%3E%3Cellipse cx='135' cy='33' rx='110' ry='16' fill='%2340A8C4' opacity='.25' transform='rotate(2 135 33)'/%3E%3C/svg%3E") no-repeat;background-size:100% 100%;z-index:-1}

.doodle-deco{position:absolute;top:0;left:0;width:100%;height:100%;pointer-events:none;z-index:0}
.deco-zigzag{position:absolute;top:-35px;left:70px;width:60px;height:40px;background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 60 40'%3E%3Cpath d='M8 38L20 4L30 22L40 4L52 38' fill='none' stroke='%234A7DDB' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") no-repeat center;background-size:contain}
.hero-text p{color:var(--text-secondary);font-size:.95rem;line-height:1.8;font-weight:400}
.hero-image{position:relative}
.hero-image img{width:100%;border-radius:24px 8px 8px 24px;object-fit:cover;aspect-ratio:4/3;transition:transform .4s ease}
.hero-image:hover img{transform:scale(1.03)}
.hero-blob-blue{position:absolute;width:160px;height:160px;background:#C5D8F0;border-radius:50%;top:-50px;right:-30px;opacity:.6;z-index:-1}
.hero-blob-beige{position:absolute;width:120px;height:120px;background:#F5E6C8;border-radius:50%;bottom:-20px;right:60px;opacity:.5;z-index:-1}

/* ===== NARRALEAF SECTION ===== */
.narraleaf{padding:60px 0 80px}
.section-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:24px;flex-wrap:wrap;gap:16px}
.section-header-text h2{font-size:1.8rem;font-weight:900;margin-bottom:8px}
.section-header-text p{color:var(--text-secondary);font-size:.9rem;max-width:680px;line-height:1.7}
.narraleaf-logo{height:64px;width:auto;object-fit:contain;transition:transform .3s ease}
.narraleaf-logo:hover{transform:scale(1.08)}
.btn-group{display:flex;gap:12px;margin-bottom:32px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:8px;padding:10px 24px;border-radius:8px;font-size:.9rem;font-weight:700;transition:all .2s;cursor:pointer;border:none}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-hover)}
.btn-outline{background:transparent;color:var(--text);border:1.5px solid var(--border)}
.btn-outline:hover{border-color:#999}

.narraleaf-grid{display:grid;grid-template-columns:1fr 1fr;grid-template-rows:auto auto;gap:16px}
.narraleaf-grid .img-large{grid-row:1/3;border-radius:var(--radius-lg);overflow:hidden}
.narraleaf-grid .img-large img{width:100%;height:100%;object-fit:cover;transition:transform .4s ease}
.narraleaf-grid .img-large:hover img{transform:scale(1.05)}
.narraleaf-grid .img-small{border-radius:var(--radius-lg);overflow:hidden}
.narraleaf-grid .img-small img{width:100%;height:100%;object-fit:cover;transition:transform .4s ease}
.narraleaf-grid .img-small:hover img{transform:scale(1.05)}

/* ===== BLOG SECTION ===== */
.blog{padding:60px 0}
.blog-grid{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center}
.blog-text{padding-right:40px}
.blog-text h2{font-size:1.8rem;font-weight:900;margin-bottom:12px}
.blog-desc{color:var(--text-secondary);font-size:1rem;line-height:1.8;margin-bottom:24px}
.blog-btn{padding:14px 36px;font-size:1rem;border-radius:12px}
.blog-image img{width:100%;border-radius:var(--radius-lg)}

/* ===== CONTACT & SOCIAL SECTION ===== */
.contact-social{padding:40px 0 80px}
.cs-grid{display:grid;grid-template-columns:1fr 1fr;gap:40px}
.cs-column{display:flex;flex-direction:column;gap:16px}
.cs-heading{font-size:1.8rem;font-weight:900}
.cs-sub{color:var(--text-secondary);font-size:.9rem;margin-bottom:4px}
.cs-card{display:flex;align-items:center;gap:20px;background:var(--card-bg);border-radius:var(--radius-lg);padding:20px 24px;transition:transform .2s,box-shadow .2s;cursor:pointer}
.cs-card:hover{transform:translateY(-2px);box-shadow:0 6px 20px rgba(0,0,0,.06)}
.cs-icon{width:52px;height:52px;border-radius:14px;display:flex;align-items:center;justify-content:center;font-size:1.5rem;flex-shrink:0;transition:transform .3s ease}
.cs-card:hover .cs-icon{transform:scale(1.1) rotate(-5deg)}
.cs-icon.qq{background:#e3f2fd;color:#1976d2}
.cs-icon.email{background:#e8f5e9;color:#4caf50}
.cs-icon.recruit{background:#fff3e0;color:#ff9800}
.cs-icon.github{background:#f3e8ff;color:#9333ea}
.cs-icon.bilibili{background:#fce4ec;color:#e91e63}
.cs-icon.afdian{background:#fff8e1;color:#f59e0b}
.cs-info{display:flex;align-items:center;justify-content:space-between;flex:1;min-width:0}
.cs-name{font-size:1rem;font-weight:700;white-space:nowrap}
.cs-detail{font-size:.85rem;color:var(--text-secondary);white-space:nowrap}
.wechat-card{position:relative;cursor:pointer}
.cs-icon.wechat{background:#e8f5e9;color:#07c160}
.wechat-popup{position:absolute;bottom:calc(100% + 12px);right:0;width:100%;border-radius:var(--radius);overflow:hidden;box-shadow:0 8px 24px rgba(0,0,0,.15);opacity:0;visibility:hidden;transform:translateY(8px);transition:opacity .25s,visibility .25s,transform .25s;pointer-events:none;z-index:10}
.wechat-popup img{width:100%;display:block}
.wechat-card:hover .wechat-popup{opacity:1;visibility:visible;transform:translateY(0)}
.wechat-card.popup-open .wechat-popup{opacity:1;visibility:visible;transform:translateY(0);pointer-events:auto}

/* ===== FRIEND LINKS ===== */
/* 上一节 .contact-social 已带 80px 下内边距，这里只补 20px，合计与其他节间距一致 */
.friends{padding:20px 0 80px}
.friends-heading{font-size:1.8rem;font-weight:900}
.friends-sub{color:var(--text-secondary);font-size:.9rem;margin-bottom:20px}
/* auto-fill + min() ：只有一条友链时不会拉成整行大卡片，之后加友链自动排成多列；
   min(340px,100%) 保证窄于 340px 的视口里不横向溢出 */
.friends-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(340px,100%),1fr));gap:16px}
.friend-card{display:flex;align-items:center;gap:20px;background:var(--card-bg);border-radius:var(--radius-lg);padding:20px 24px;transition:transform .2s,box-shadow .2s}
.friend-card:hover{transform:translateY(-2px);box-shadow:0 6px 20px rgba(0,0,0,.06)}
/* 对方 Logo 是纯黑线稿（透明底），深色主题下整体反相为纯白，否则会糊在深色卡片上 */
.friend-logo{height:104px;width:auto;flex-shrink:0;transition:transform .3s ease}
@media(prefers-color-scheme:dark){.friend-logo{filter:invert(1)}}
.friend-card:hover .friend-logo{transform:scale(1.06)}
.friend-info{display:flex;flex-direction:column;gap:6px;min-width:0}
.friend-name{font-size:1rem;font-weight:700}
.friend-desc{font-size:.85rem;line-height:1.7;color:var(--text-secondary)}

/* ===== FOOTER ===== */
footer{border-top:1px solid var(--border);padding:24px 0}
.footer-inner{display:flex;align-items:center;justify-content:space-between}
.footer-logo{display:flex;align-items:center;font-weight:700}
.footer-logo img{height:24px;width:auto}
.footer-copy{font-size:.8rem;color:#999}

/* ===== LOGO THEME SWITCH ===== */
/* 深色 logo 用在浅色底上，浅色 logo 用在深色底上 */
.light-logo{display:block}
.dark-logo{display:none}
@media(prefers-color-scheme:dark){
  .light-logo{display:none}
  .dark-logo{display:block}
}

/* ===== RESPONSIVE ===== */
@media(max-width:768px){
  .hero-grid{grid-template-columns:1fr;text-align:center}
  .hero-text h1{font-size:2rem}
  .hero-blob-blue,.hero-blob-beige{display:none}
  .hero-text h1.doodle::before,.doodle-deco{display:none}
  .section-header{flex-direction:column}
  .narraleaf-logo{order:-1;align-self:flex-start}
  .narraleaf-grid{grid-template-columns:1fr}
  .narraleaf-grid .img-large{grid-row:auto}
  .blog-grid{grid-template-columns:1fr}
  .blog-text{padding-right:0;text-align:center}
  .blog-btn{margin:0 auto}
  .blog-image{order:-1}
  .cs-grid{grid-template-columns:1fr}
  .header-inner{height:56px}
  .hamburger{display:flex}
  .nav-links{display:none;position:absolute;top:56px;left:0;right:0;flex-direction:column;gap:0;background:var(--header-bg);backdrop-filter:blur(12px);border-bottom:1px solid var(--border);padding:8px 0}
  .nav-links.open{display:flex}
  .nav-links>a{padding:12px 24px;font-size:.95rem;border-bottom:1px solid var(--border)}
  .nav-links>a:last-of-type{border-bottom:none}
  .nav-links>a.active::after{display:none}
  .nav-actions{padding:8px 24px 4px;gap:16px;justify-content:flex-start}
  .nav-actions .nav-icon{font-size:1.3rem}
  .nav-actions .lang-toggle{font-size:1.2rem}
  .logo img{height:27px}
  .footer-inner{flex-direction:column;gap:12px;text-align:center}
  .footer-logo{justify-content:center}
}
@media(max-width:480px){
  .hero-text h1{font-size:1.6rem}
  .header-inner{padding:0 12px}
  .container{padding:0 12px}
  .cs-card{padding:16px}
  .cs-icon{width:44px;height:44px;font-size:1.3rem}
  .friend-card{padding:16px;gap:16px}
  .friend-logo{height:88px}
}

/* ===== THEME TRANSITION ===== */
body,.header-inner,.card,.btn,.nav-links>a{transition:background .3s,color .3s,border-color .3s,box-shadow .3s}

/* ===== SELECTION ===== */
::selection{background:rgba(64,168,196,.25);color:inherit}

/* ===== SKIP LINK ===== */
.skip-link{position:absolute;top:-100%;left:16px;background:var(--primary);color:#fff;padding:8px 16px;border-radius:0 0 8px 8px;font-size:.85rem;font-weight:600;z-index:999;transition:top .2s}
.skip-link:focus{top:0}

/* ===== BACK TO TOP ===== */
.back-to-top{position:fixed;bottom:32px;right:32px;width:44px;height:44px;border-radius:50%;background:var(--primary);color:#fff;border:none;cursor:pointer;font-size:1rem;display:flex;align-items:center;justify-content:center;opacity:0;visibility:hidden;transform:translateY(12px);transition:opacity .3s,visibility .3s,transform .3s,background .2s;z-index:90;box-shadow:0 4px 12px rgba(0,0,0,.15)}
.back-to-top.visible{opacity:1;visibility:visible;transform:translateY(0)}
.back-to-top:hover{background:var(--primary-hover)}

/* ===== LANGUAGE SUGGESTION BANNER =====
   仅当浏览器环境为英文/日文、且用户尚未选择过语言时，由 main.js 动态插入。
   刻意不写进 index.html：静态源码里保持纯中文，爬虫抓到的仍是中文页面。
   定位避开 .back-to-top（右下 32px，44px 见方）：桌面端靠左，移动端上移。 */
.lang-banner{position:fixed;bottom:24px;left:24px;z-index:95;max-width:400px;display:flex;align-items:flex-start;gap:12px;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);padding:16px;box-shadow:0 8px 24px rgba(0,0,0,.12);opacity:0;visibility:hidden;transform:translateY(12px);transition:opacity .3s,visibility .3s,transform .3s}
.lang-banner.show{opacity:1;visibility:visible;transform:translateY(0)}
.lang-banner-icon{margin-top:3px;color:var(--primary)}
.lang-banner-body{flex:1;min-width:0}
.lang-banner-text{font-size:.85rem;line-height:1.5;color:var(--text-secondary);margin-bottom:12px}
/* 是 <a> 不是 <button>：切换语言 = 跳转到另一个 URL，所以要 display 成块级可点区域 */
.lang-banner-switch{display:inline-block;padding:8px 16px;border-radius:8px;background:var(--primary);color:#fff;border:none;cursor:pointer;font-size:.8rem;font-weight:700;font-family:var(--font-sans);transition:background .2s}
.lang-banner-switch:hover{background:var(--primary-hover);color:#fff}
.lang-banner-close{flex-shrink:0;width:22px;height:22px;display:flex;align-items:center;justify-content:center;background:none;border:none;cursor:pointer;border-radius:6px;font-size:1.1rem;line-height:1;color:var(--text-secondary);font-family:var(--font-sans);transition:background .15s,color .15s}
.lang-banner-close:hover{background:var(--bg-light);color:var(--text)}
@media(max-width:768px){
  .lang-banner{left:12px;right:12px;bottom:88px;max-width:none}
}
@media(prefers-reduced-motion:reduce){
  .lang-banner{transition:none}
}