/*
Theme Name: Minimal XL
Theme URI: http://47.113.186.231
Author: XL
Description: A modern blog theme — clean typography, generous whitespace, clear hierarchy.
Version: 4.8
*/

:root {
  --bg: #fafbfc;
  --card-bg: #ffffff;
  --text: #1d2129;
  --text-secondary: #4e5969;
  --text-tertiary: #86909c;
  --accent: #4361ee;
  --accent-hover: #3451d1;
  --accent-light: #eef1ff;
  --accent-gradient: linear-gradient(135deg, #4361ee 0%, #7c3aed 100%);
  --green: #10b981;
  --green-light: #ecfdf5;
  --orange: #f59e0b;
  --orange-light: #fef3c7;
  --red: #ef4444;
  --red-light: #fef2f2;
  --purple: #7c3aed;
  --purple-light: #f3e8ff;
  --light: #86909c;
  --border: #e5e6eb;
  --content-width: 860px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.04);
  --shadow: 0 4px 16px rgba(0,0,0,.06);
  --shadow-hover: 0 8px 32px rgba(0,0,0,.1);
  --radius-sm: 8px;
  --radius: 12px;
  --radius-lg: 16px;
  --timeline-line: #d4d8e0;
  --serif: 'Noto Serif SC','Source Han Serif SC','STSong',Georgia,serif;
  --sans: -apple-system,'PingFang SC','Hiragino Sans GB','Microsoft YaHei','Helvetica Neue',Arial,sans-serif;
  --mono: 'JetBrains Mono','Fira Code','SF Mono',Consolas,monospace;
}

*{margin:0;padding:0;box-sizing:border-box}
html{font-size:16px;scroll-behavior:smooth;-webkit-text-size-adjust:100%}

body{
  font-family:var(--sans);
  background:var(--bg);color:var(--text);line-height:1.75;
  -webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;
  overflow-x:hidden;
}
a{color:var(--accent);text-decoration:none;transition:color .2s}
a:hover{color:var(--accent-hover)}
img{max-width:100%;height:auto;display:block}

::selection{background:var(--accent);color:#fff}

/* ========== Header ========== */
.site-header{
  background:rgba(255,255,255,.92);
  backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);
  border-bottom:1px solid var(--border);
  position:sticky;top:0;z-index:100;
}
.header-inner{
  max-width:var(--content-width);margin:0 auto;
  display:flex;align-items:center;justify-content:space-between;
  height:56px;padding:0 24px;
}
.header-left{display:flex;align-items:center;gap:12px;min-width:0;flex-shrink:1}
.site-title{font-size:1.08rem;font-weight:800;letter-spacing:-.3px;white-space:nowrap}
.site-title a{
  background:var(--accent-gradient);
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;
}
.site-description{display:none}
.site-nav{display:flex;align-items:center;gap:2px;flex-shrink:0}
.site-nav a{
  padding:5px 14px;font-size:.84rem;color:var(--text-tertiary);
  font-weight:500;border-radius:6px;transition:all .2s;white-space:nowrap;
}
.site-nav a:hover,.site-nav a.nav-active{color:var(--accent);background:var(--accent-light)}

.mobile-menu-toggle{display:none;background:none;border:none;cursor:pointer;flex-direction:column;gap:5px;padding:4px}
.mobile-menu-toggle span{display:block;width:20px;height:2px;background:var(--text);border-radius:2px;transition:.3s}

/* ========== Hero ========== */
.hero-section{
  background:var(--accent-gradient);
  padding:56px 24px 48px;
  margin-bottom:0;
}
.hero-inner{
  max-width:var(--content-width);margin:0 auto;
  display:grid;grid-template-columns:1fr auto;gap:40px;align-items:center;
}
.hero-text{min-width:0;overflow:hidden}
.hero-greeting{display:inline-block;font-size:.92rem;color:rgba(255,255,255,.75);margin-bottom:8px}
.hero-title{
  font-size:2rem;font-weight:800;color:#fff;line-height:1.3;
  margin-bottom:12px;word-break:break-word;
}
.hero-desc{font-size:1rem;color:rgba(255,255,255,.85);margin-bottom:24px;line-height:1.6}
.hero-stats{display:flex;gap:14px}
.stat-item{background:rgba(255,255,255,.14);padding:12px 22px;border-radius:10px;text-align:center}
.stat-num{display:block;font-size:1.5rem;font-weight:800;color:#fff}
.stat-label{font-size:.72rem;color:rgba(255,255,255,.8)}

.hero-visual{display:flex;justify-content:center;flex-shrink:0}
.hero-code-window{
  background:#1e1e2e;border-radius:var(--radius);overflow:hidden;
  box-shadow:0 16px 40px rgba(0,0,0,.25);width:280px;
}
.code-titlebar{padding:10px 14px;display:flex;gap:6px;background:rgba(0,0,0,.2)}
.dot{width:10px;height:10px;border-radius:50%}
.dot.r{background:#ff5f57}.dot.y{background:#ffbd2e}.dot.g{background:#28ca41}
.hero-code{padding:18px;margin:0;font-family:var(--mono);font-size:.74rem;line-height:1.7;color:#cdd6f4;overflow:hidden}

/* ========== Category Bar ========== */
.category-nav{background:#fff;border-bottom:1px solid var(--border);position:sticky;top:56px;z-index:50}
.category-inner{max-width:var(--content-width);margin:0 auto;padding:10px 24px;display:flex;gap:6px;overflow-x:auto;scrollbar-width:none}
.category-inner::-webkit-scrollbar{display:none}
.nav-item{display:flex;flex-direction:column;align-items:center;gap:1px;padding:6px 14px;border-radius:8px;text-decoration:none;color:var(--text);background:var(--bg);border:1px solid transparent;transition:all .2s;min-width:48px;flex-shrink:0}
.nav-item:hover{background:var(--accent-light);color:var(--accent)}
.nav-item.active{background:var(--accent);color:#fff}
.nav-item .n{font-size:.95rem;font-weight:800;line-height:1}
.nav-item .l{font-size:.68rem;font-weight:500;white-space:nowrap}

/* ========== Content Layout ========== */
.content-layout{max-width:var(--content-width);margin:0 auto;display:grid;grid-template-columns:200px 1fr;min-height:60vh}

.timeline-aside{background:var(--bg);border-right:1px solid var(--border);padding:20px 12px;position:sticky;top:104px;height:calc(100vh - 104px);overflow-y:auto;align-self:start}
.timeline-bar{position:relative;padding-left:16px}
.timeline-line{position:absolute;left:0;top:8px;bottom:40px;width:2px;background:var(--timeline-line)}

.tl-folder{margin-bottom:8px}
.tl-folder-head{display:flex;align-items:center;gap:6px;cursor:pointer;padding:4px 0;user-select:none}
.tl-folder-head:hover .tl-month{color:var(--accent)}
.tl-arrow{font-size:.55rem;color:var(--accent);transition:transform .25s;flex-shrink:0}
.tl-folder.open .tl-arrow{transform:rotate(90deg)}
.tl-month{font-size:.76rem;font-weight:700;color:var(--text);white-space:nowrap}
.tl-count{font-size:.62rem;color:var(--text-tertiary);margin-left:auto;background:#e8eaed;padding:1px 6px;border-radius:6px;flex-shrink:0}
.tl-folder-body{max-height:0;overflow:hidden;transition:max-height .35s ease}
.tl-folder.open .tl-folder-body{max-height:800px}

.tl-item{display:flex;align-items:center;gap:6px;padding:3px 0 3px 14px;text-decoration:none;position:relative;font-size:.72rem}
.tl-item:hover .tl-title{color:var(--accent)}
.tl-dot{position:absolute;left:-4px;top:50%;transform:translateY(-50%);width:6px;height:6px;border-radius:50%;background:var(--accent);border:2px solid var(--bg);box-shadow:0 0 0 1px var(--accent)}
.tl-date{color:var(--text-tertiary);font-size:.66rem;min-width:36px;flex-shrink:0}
.tl-title{color:var(--text-secondary);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;min-width:0}

/* ========== Posts Main ========== */
.posts-main{padding:28px 24px 40px}

.post-summary{padding:24px 0;border-bottom:1px solid var(--border)}
.post-summary:first-child{padding-top:0}
.ps-title{font-size:1.15rem;font-weight:700;margin-bottom:8px;line-height:1.45;word-break:break-word}
.ps-title a{color:var(--text);text-decoration:none}
.ps-title a:hover{color:var(--accent)}
.ps-meta{display:flex;align-items:center;gap:8px;margin-bottom:8px;flex-wrap:wrap}
.ps-date{font-size:.78rem;color:var(--text-tertiary)}
.ps-cat{font-size:.7rem;padding:2px 10px;border-radius:10px;background:var(--accent-light);color:var(--accent);font-weight:600}
.ps-excerpt{font-size:.9rem;color:var(--text-secondary);line-height:1.75;margin-bottom:12px;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.ps-link{font-size:.82rem;color:var(--accent);font-weight:600;text-decoration:none;display:inline-flex;align-items:center;gap:4px}
.ps-link:hover{color:var(--accent-hover);text-decoration:underline}
.ps-more{padding-top:28px;text-align:center}
.ps-more a{font-size:.86rem;color:var(--accent);font-weight:600;text-decoration:none}
.ps-more a:hover{text-decoration:underline}

/* ========== Single Post ========== */
.single-post{max-width:720px;margin:0 auto;padding:44px 24px 80px}
.back-home{display:inline-block;margin-bottom:20px;font-size:.86rem;color:var(--text-tertiary)}
.back-home:hover{color:var(--accent)}
.post-header .post-title{font-size:1.72rem;font-weight:800;line-height:1.4;margin-bottom:16px;word-break:break-word}
.post-meta{margin-bottom:20px}
.post-author{display:flex;align-items:center;gap:10px;margin-bottom:20px}
.author-avatar img{border-radius:50%}
.author-name{font-size:.86rem;color:var(--text-secondary);font-weight:500}
.post-thumbnail{border-radius:var(--radius);overflow:hidden;margin-bottom:24px}
.post-content{font-size:1.02rem;line-height:1.9;color:var(--text)}
.post-content h2{font-size:1.38rem;margin:2em 0 .8em;font-weight:700}
.post-content h3{font-size:1.18rem;margin:1.5em 0 .6em;font-weight:600}
.post-content p{margin-bottom:1.2em}
.post-content code{background:var(--bg);padding:2px 6px;border-radius:4px;font-size:.86em;font-family:var(--mono)}
.post-content pre{background:#1e1e2e;color:#cdd6f4;padding:20px;border-radius:var(--radius);overflow-x:auto;margin:1.5em 0;font-size:.84rem;line-height:1.6}
.post-content pre code{background:none;padding:0;color:inherit}
.post-content blockquote{border-left:3px solid var(--accent);padding:14px 20px;margin:1.5em 0;background:var(--accent-light);border-radius:0 var(--radius-sm) var(--radius-sm) 0;color:var(--text-secondary)}
.post-content ul,.post-content ol{padding-left:24px;margin-bottom:1em}
.post-content li{margin-bottom:.4em}
.post-content img{border-radius:var(--radius);margin:1em 0}
.post-tags-bottom{display:flex;gap:8px;flex-wrap:wrap;margin:32px 0;padding-top:24px;border-top:1px solid var(--border)}
.post-nav{display:flex;justify-content:space-between;gap:16px;margin-top:40px;padding-top:24px;border-top:1px solid var(--border);font-size:.86rem}

/* ========== Footer ========== */
.site-footer{background:#1a1a2e;color:rgba(255,255,255,.7);padding:20px 24px 10px}
.footer-inner{max-width:520px;margin:0 auto}
.footer-top{display:grid;grid-template-columns:2fr 1fr;gap:14px;margin-bottom:10px}
.footer-brand h3{font-size:.8rem;font-weight:700;color:#fff;margin-bottom:2px}
.footer-brand p{font-size:.68rem;line-height:1.4}
.footer-links{display:grid;grid-template-columns:1fr 1fr;gap:24px}
.footer-col h4{font-size:.66rem;color:#fff;margin-bottom:4px;font-weight:600}
.footer-col a{display:block;font-size:.66rem;color:rgba(255,255,255,.55);padding:1px 0;transition:color .2s}
.footer-col a:hover{color:#fff}
.footer-bottom{padding-top:8px;border-top:1px solid rgba(255,255,255,.1);text-align:center;font-size:.66rem;color:rgba(255,255,255,.4)}

/* ========== Pagination ========== */
.pagination{max-width:var(--content-width);margin:0 auto;padding:0 24px 40px}
.nav-links{display:flex;gap:8px;justify-content:center;flex-wrap:wrap}
.nav-links a,.nav-links span{padding:7px 14px;border-radius:8px;font-size:.84rem;background:var(--card-bg);border:1px solid var(--border);color:var(--text-secondary);transition:all .2s}
.nav-links a:hover{background:var(--accent-light);color:var(--accent);border-color:var(--accent)}
.nav-links span.current{background:var(--accent);color:#fff;border-color:var(--accent)}

/* ========== Empty State ========== */
.empty-state{text-align:center;padding:80px 24px;color:var(--light)}
.empty-icon{font-size:3rem;margin-bottom:16px}

/* ========== Questions Page ========== */
.questions-page{min-height:60vh}
.questions-hero{background:linear-gradient(135deg,#4361ee 0%,#7c3aed 50%,#a855f7 100%);padding:32px 24px 24px;text-align:center;color:#fff}
.questions-title{font-size:1.4rem;font-weight:800;margin-bottom:6px}
.questions-desc{font-size:.84rem;color:rgba(255,255,255,.85);margin-bottom:16px}
.questions-stats{display:flex;justify-content:center;gap:18px}
.q-stat{background:rgba(255,255,255,.15);padding:8px 18px;border-radius:8px;text-align:center;backdrop-filter:blur(10px)}
.q-stat-num{display:block;font-size:1.1rem;font-weight:800}
.q-stat-label{font-size:.72rem;color:rgba(255,255,255,.8)}

.questions-filter{max-width:var(--content-width);margin:0 auto;padding:18px 24px;display:flex;align-items:center;gap:12px;flex-wrap:wrap;border-bottom:1px solid var(--border)}
.filter-group{display:flex;gap:6px}
.filter-btn{padding:5px 14px;font-size:.8rem;border-radius:18px;color:var(--light);background:var(--card-bg);border:1px solid var(--border);font-weight:500;transition:all .2s;cursor:pointer}
.filter-btn:hover{color:var(--accent);border-color:var(--accent)}
.filter-btn.active{background:var(--accent);color:#fff;border-color:var(--accent)}

/* Date folder */
.folder-item{padding-bottom:10px}
.folder-item .timeline-card{padding:0;overflow:hidden}
.date-folder{width:100%}
.date-folder-header{display:flex;align-items:center;gap:10px;padding:14px 18px;background:var(--bg);cursor:pointer;transition:all .2s;border-bottom:1px solid transparent}
.date-folder.open .date-folder-header{border-bottom-color:var(--border)}
.date-folder-header:hover{background:var(--accent-light)}
.date-folder-icon{transition:transform .3s;font-size:.82rem;color:var(--accent)}
.date-folder.open .date-folder-icon{transform:rotate(90deg)}
.date-folder-label{font-weight:700;font-size:.88rem;color:var(--text)}
.date-folder-count{font-size:.76rem;color:var(--light);margin-left:auto}
.date-folder-body{max-height:0;overflow:hidden;transition:max-height .4s ease}
.date-folder.open .date-folder-body{max-height:5000px}
.question-sub-item{padding:0 18px}
.question-sub-item .timeline-card{margin-bottom:6px;border:none;box-shadow:none;border-radius:0;border-bottom:1px solid var(--border)}
.question-sub-item:last-child .timeline-card{border-bottom:none;margin-bottom:0}
.question-sub-item .timeline-card:hover{box-shadow:var(--shadow-sm);transform:none}

.q-category{font-size:.7rem;padding:2px 10px;border-radius:10px;font-weight:600}
.q-category.bigdata-interview{background:var(--accent-light);color:var(--accent)}
.q-category.algorithm{background:var(--purple-light);color:var(--purple)}
.q-source,.q-author{font-size:.74rem;color:var(--light)}
.q-title{cursor:pointer}
.q-content{max-height:0;overflow:hidden;transition:max-height .4s ease,margin .3s ease}
.timeline-card.expanded .q-content{max-height:600px;margin-top:10px}
.q-text{font-size:.86rem;line-height:1.8;color:var(--text-secondary);white-space:pre-wrap;word-break:break-word;background:var(--bg);padding:14px;border-radius:8px}
.q-footer{display:flex;align-items:center;gap:8px;margin-top:8px}
.q-copy-btn,.q-edit-btn,.q-del-btn{font-size:.76rem;padding:4px 12px;border-radius:6px;border:1px solid var(--border);background:var(--card-bg);color:var(--light);cursor:pointer;transition:all .2s}
.q-copy-btn:hover{border-color:var(--accent);color:var(--accent)}
.q-edit-btn:hover{border-color:var(--green);color:var(--green)}
.q-del-btn:hover{border-color:var(--red);color:var(--red);background:var(--red-light)}
.admin-actions{display:none;gap:6px}

/* ========== Notes Page ========== */
.notes-page{min-height:60vh}
.notes-hero{background:linear-gradient(135deg,#10b981 0%,#4361ee 100%);padding:28px 24px 20px;text-align:center;color:#fff}
.notes-title{font-size:1.4rem;font-weight:800;margin-bottom:4px}
.notes-desc{font-size:.84rem;color:rgba(255,255,255,.85)}
.notes-app{padding-bottom:60px}
.notes-toolbar{max-width:var(--content-width);margin:0 auto;padding:18px 24px;display:flex;align-items:center;gap:12px;flex-wrap:wrap;border-bottom:1px solid var(--border)}
.note-add-btn{padding:7px 18px;font-size:.84rem;font-weight:600;background:var(--accent);color:#fff;border:none;border-radius:8px;cursor:pointer;transition:all .2s}
.note-add-btn:hover{background:var(--accent-hover)}
.notes-search input{padding:7px 14px;border:1px solid var(--border);border-radius:8px;font-size:.84rem;background:var(--card-bg);width:180px}
.notes-search input:focus{outline:none;border-color:var(--accent)}
.notes-filter-tags{display:flex;gap:6px;flex-wrap:wrap}
.tag-filter{padding:4px 14px;font-size:.76rem;border-radius:14px;border:1px solid var(--border);background:var(--card-bg);color:var(--light);cursor:pointer;transition:all .2s;font-weight:500}
.tag-filter:hover{border-color:var(--accent);color:var(--accent)}
.tag-filter.active{background:var(--accent);color:#fff;border-color:var(--accent)}

.note-card-tag{font-size:.7rem;padding:2px 10px;border-radius:10px;font-weight:600}
.note-card-tag.idea{background:var(--orange-light);color:#d97706}
.note-card-tag.knowledge{background:var(--accent-light);color:var(--accent)}
.note-card-tag.todo{background:var(--green-light);color:var(--green)}
.note-card-tag.code{background:var(--purple-light);color:var(--purple)}

.note-card-title{cursor:pointer}
.note-click-hint{font-size:.76rem;color:var(--accent);cursor:pointer;font-weight:500}
.note-click-hint:hover{text-decoration:underline}
.notes-empty{text-align:center;padding:60px 0;color:var(--light)}

/* ========== Admin Panel ========== */
.admin-toggle-btn{margin-left:auto;padding:5px 14px;font-size:.78rem;font-weight:600;border:1px solid var(--border);border-radius:8px;background:var(--card-bg);color:var(--light);cursor:pointer;transition:all .2s}
.admin-toggle-btn:hover{border-color:var(--accent);color:var(--accent)}

.admin-panel{max-width:var(--content-width);margin:0 auto;padding:14px 24px;background:var(--card-bg);border-bottom:1px solid var(--border);border-radius:0 0 var(--radius-sm) var(--radius-sm)}
.admin-login{display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.admin-login h3{font-size:.88rem;font-weight:700}
.admin-input{padding:7px 12px;border:1px solid var(--border);border-radius:6px;font-size:.84rem;width:180px}
.admin-input:focus{outline:none;border-color:var(--accent)}
.admin-btn{padding:7px 18px;font-size:.84rem;font-weight:600;background:var(--accent);color:#fff;border:none;border-radius:6px;cursor:pointer}
.admin-btn:hover{background:var(--accent-hover)}
.admin-toolbar{display:flex;align-items:center;gap:12px}
.admin-status{font-size:.8rem;color:var(--green);font-weight:600}
.admin-action-btn{padding:5px 14px;font-size:.78rem;font-weight:600;border-radius:6px;border:none;cursor:pointer;transition:all .2s}
.admin-action-btn.add-btn{background:var(--accent);color:#fff}
.admin-action-btn.add-btn:hover{background:var(--accent-hover)}
.admin-action-btn.logout-btn{background:var(--red-light);color:var(--red)}
.admin-action-btn.logout-btn:hover{background:var(--red);color:#fff}

/* ========== Editor Overlay ========== */
.note-editor-overlay{position:fixed;inset:0;background:rgba(0,0,0,.45);z-index:1000;display:flex;align-items:center;justify-content:center;backdrop-filter:blur(4px)}
.note-editor{background:var(--card-bg);border-radius:var(--radius-lg);width:90%;max-width:580px;max-height:85vh;overflow-y:auto;box-shadow:0 20px 60px rgba(0,0,0,.18)}
.editor-header{display:flex;justify-content:space-between;align-items:center;padding:18px 22px;border-bottom:1px solid var(--border)}
.editor-header h3{font-size:1.04rem;font-weight:700}
.editor-close{width:30px;height:30px;border:none;background:var(--bg);border-radius:6px;font-size:.96rem;cursor:pointer;color:var(--light)}
.editor-body{padding:18px 22px}
.editor-title-input{width:100%;padding:10px 14px;font-size:1rem;border:1px solid var(--border);border-radius:8px;margin-bottom:12px;background:var(--bg)}
.editor-title-input:focus{outline:none;border-color:var(--accent)}
.editor-tag-select{display:flex;gap:6px;flex-wrap:wrap;align-items:center;margin-bottom:12px}
.editor-tag-select label{font-size:.82rem;color:var(--light)}
.tag-select-btn{padding:4px 12px;font-size:.76rem;border:1px solid var(--border);background:var(--card-bg);border-radius:12px;cursor:pointer;transition:all .2s;color:var(--light)}
.tag-select-btn.active{background:var(--accent);color:#fff;border-color:var(--accent)}
.editor-content{width:100%;min-height:180px;padding:12px;font-size:.9rem;border:1px solid var(--border);border-radius:8px;resize:vertical;background:var(--bg);line-height:1.7;font-family:inherit}
.editor-content:focus{outline:none;border-color:var(--accent)}
.editor-footer{padding:14px 22px;border-top:1px solid var(--border);display:flex;gap:10px}
.editor-save{padding:8px 24px;font-size:.86rem;font-weight:600;color:#fff;background:var(--accent);border:none;border-radius:8px;cursor:pointer;transition:all .2s}
.editor-save:hover{background:var(--accent-hover)}
.editor-delete{padding:8px 18px;font-size:.86rem;font-weight:600;color:var(--red);background:var(--red-light);border:none;border-radius:8px;cursor:pointer;transition:all .2s}
.editor-delete:hover{background:var(--red);color:#fff}

/* ========== Post Admin ========== */
.post-admin-section{padding:28px 0}
.post-admin-section h3{font-size:1.04rem;font-weight:700;margin-bottom:14px;padding-left:80px}
.post-admin-actions{display:flex;gap:8px;flex-wrap:wrap;padding-left:80px;margin-bottom:20px}

/* ========== Responsive ========== */
@media(max-width:768px){
  html{font-size:15px}

  .hero-inner{grid-template-columns:1fr;text-align:center}
  .hero-stats{justify-content:center}
  .hero-visual{display:none}
  .hero-section{padding:40px 16px 32px}
  .hero-title{font-size:1.6rem}
  .hero-desc{font-size:.9rem}

  .site-nav{
    display:none;position:fixed;top:56px;left:0;right:0;bottom:0;
    background:var(--card-bg);flex-direction:column;padding:16px;gap:4px;
    box-shadow:var(--shadow);z-index:90;overflow-y:auto;
  }
  .site-nav.active{display:flex}
  .site-nav a{padding:12px 16px;font-size:.92rem;border-radius:8px}
  .mobile-menu-toggle{display:flex}
.site-nav.nav-open{display:flex!important;flex-direction:column!important;position:fixed!important;top:56px!important;left:0!important;right:0!important;bottom:0!important;background:#fff;padding:12px 20px;gap:10px;z-index:100;box-shadow:0 4px 12px rgba(0,0,0,.08);overflow-y:auto!important}
.site-nav.nav-open a{padding:8px 0;border-bottom:1px solid #f0f0f0;font-size:.92rem}

  .content-layout{grid-template-columns:1fr}
  .timeline-aside{display:none}
  .posts-main{padding:20px 16px 32px}

  .category-inner{padding:10px 12px}
  .nav-item{padding:5px 10px;min-width:40px}
  .nav-item .n{font-size:.84rem}
  .nav-item .l{font-size:.64rem}

  .questions-filter,.notes-toolbar{padding:14px 12px;flex-direction:column;align-items:flex-start}
  .admin-toggle-btn{margin-left:0}
  .footer-top{grid-template-columns:1fr;gap:20px}
  .single-post{padding:24px 16px 40px}
  .post-header .post-title{font-size:1.4rem}

  /* Fix: 登录按钮在移动端 */
  .nav-login-btn{margin-left:auto;margin-right:4px}
  .admin-login-dropdown{right:12px;left:12px;top:52px;min-width:auto}
}

/* ========== Smooth Transitions ========== */
.timeline-card,.post-summary,.cat-card{transition:all .25s ease}
.timeline-card:hover{box-shadow:var(--shadow-hover);transform:translateY(-1px)}

/* ========== Scrollbar ========== */
::-webkit-scrollbar{width:6px;height:6px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:#c4c7cc;border-radius:3px}
::-webkit-scrollbar-thumb:hover{background:#a0a4ab}