/* =========================================================
   Personal Site — Glass / Modern Theme
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* ---------- Design tokens ---------- */
:root {
    --color-bg: #08080c;
    --color-bg-elevated: rgba(255, 255, 255, 0.05);
    --color-bg-elevated-hover: rgba(255, 255, 255, 0.08);
    --color-text: #f5f5f7;
    --color-text-muted: rgba(245, 245, 247, 0.65);
    --color-text-faint: rgba(245, 245, 247, 0.42);
    --color-border: rgba(255, 255, 255, 0.08);
    --color-border-strong: rgba(255, 255, 255, 0.16);
    --color-accent: #a855f7;
    --color-accent-2: #06b6d4;
    --gradient-accent: linear-gradient(135deg, #a855f7 0%, #06b6d4 100%);
    --gradient-text: linear-gradient(135deg, #c084fc 0%, #67e8f9 100%);

    --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem;
    --space-4: 1rem;    --space-5: 1.25rem; --space-6: 1.5rem;
    --space-8: 2rem;    --space-10: 2.5rem; --space-12: 3rem;
    --space-16: 4rem;   --space-20: 5rem;   --space-24: 6rem;
    --space-32: 8rem;

    --radius-sm: 8px; --radius-md: 12px;
    --radius-lg: 16px; --radius-xl: 24px;
    --radius-full: 9999px;

    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI Variable', 'Segoe UI', 'PingFang SC', 'Microsoft YaHei UI', 'Microsoft YaHei', 'Noto Sans SC', system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, Monaco, Consolas, monospace;

    --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.32);
    --shadow-card-hover: 0 16px 48px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(168, 85, 247, 0.35);
    --shadow-glow: 0 0 40px rgba(168, 85, 247, 0.3);

    --container-max: 1100px;
    --container-narrow: 720px;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.65;
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}
img, video { max-width: 100%; display: block; }
a { color: inherit; }
::selection { background: rgba(168, 85, 247, 0.4); color: white; }

/* ---------- Layout ---------- */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-6);
    position: relative;
    z-index: 1;
}

/* ---------- Navigation ---------- */
nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(8, 8, 12, 0.65);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-4) 0;
}
nav .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    font-size: 1.0625rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}
.nav-links {
    display: flex;
    list-style: none;
    gap: var(--space-8);
}
.nav-links a {
    text-decoration: none;
    color: var(--color-text-muted);
    font-weight: 500;
    font-size: 0.9375rem;
    position: relative;
    padding: var(--space-2) 0;
    transition: color 0.2s ease;
}
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--gradient-accent);
    transition: width 0.3s ease;
}
.nav-links a:hover { color: var(--color-text); }
.nav-links a:hover::after { width: 100%; }

/* ---------- Language switcher ---------- */
.lang-switcher {
    display: inline-flex;
    align-items: center;
    gap: 2px;
    padding: 3px;
    margin-left: var(--space-6);
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}
.lang-switcher button {
    appearance: none;
    background: transparent;
    border: none;
    color: var(--color-text-muted);
    font-family: inherit;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    padding: 4px 10px;
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: color 0.2s ease, background 0.2s ease;
    line-height: 1;
}
.lang-switcher button:hover {
    color: var(--color-text);
}
.lang-switcher button.is-active {
    background: var(--gradient-accent);
    color: white;
}

/* 文章中文专属提示（非中文模式才显示） */
.post-cjk-notice {
    background: rgba(168, 85, 247, 0.08);
    border: 1px solid rgba(168, 85, 247, 0.2);
    color: var(--color-text-muted);
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-md);
    margin: 0 0 var(--space-8);
    font-size: 0.875rem;
    text-align: center;
}
html[lang="zh-CN"] .post-cjk-notice {
    display: none;
}

/* ---------- Hero (homepage) ---------- */
.hero {
    padding: var(--space-32) 0 var(--space-24);
    text-align: center;
}
.hero-eyebrow {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    margin-bottom: var(--space-6);
    padding: var(--space-2) var(--space-5);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    background: var(--color-bg-elevated);
    backdrop-filter: blur(10px);
}
.hero h1 {
    font-size: clamp(2.5rem, 6vw, 4.25rem);
    font-weight: 700;
    line-height: 1.05;
    letter-spacing: -0.045em;
    margin-bottom: var(--space-6);
}
.hero h1 .highlight {
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}
.hero p.subtitle {
    font-size: clamp(1rem, 1.5vw, 1.1875rem);
    color: var(--color-text-muted);
    max-width: 580px;
    margin: 0 auto var(--space-10);
    line-height: 1.65;
}
.hero-actions {
    display: flex;
    gap: var(--space-4);
    justify-content: center;
    flex-wrap: wrap;
}

/* ---------- Page hero (secondary pages) ---------- */
.page-hero {
    padding: var(--space-20) 0 var(--space-12);
    text-align: center;
}
.page-eyebrow {
    display: inline-block;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    margin-bottom: var(--space-4);
}
.page-title {
    font-size: clamp(2rem, 4.5vw, 2.875rem);
    font-weight: 700;
    letter-spacing: -0.035em;
    line-height: 1.1;
    margin-bottom: var(--space-4);
}
.page-subtitle {
    font-size: 1.0625rem;
    color: var(--color-text-muted);
    max-width: 580px;
    margin: 0 auto;
    line-height: 1.6;
}

/* ---------- Buttons ---------- */
.btn,
.cta-button {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: 0.9375rem;
    text-decoration: none;
    cursor: pointer;
    border: 1px solid transparent;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
    white-space: nowrap;
}
.btn-primary,
.cta-button {
    background: var(--gradient-accent);
    color: white;
    box-shadow: 0 4px 24px rgba(168, 85, 247, 0.35);
}
.btn-primary:hover,
.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 32px rgba(168, 85, 247, 0.5);
}
.btn-secondary {
    background: var(--color-bg-elevated);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    color: var(--color-text);
    border-color: var(--color-border-strong);
}
.btn-secondary:hover {
    transform: translateY(-2px);
    border-color: var(--color-accent);
    background: rgba(168, 85, 247, 0.12);
}

/* ---------- Content sections ---------- */
.content {
    background: transparent;
    padding: var(--space-12) 0 var(--space-20);
}
.section { margin-bottom: var(--space-20); }
.section:last-child { margin-bottom: 0; }
.section h2 {
    font-size: clamp(1.5rem, 2.5vw, 2rem);
    font-weight: 700;
    letter-spacing: -0.025em;
    margin-bottom: var(--space-10);
    text-align: center;
}

/* ---------- Glass cards ---------- */
.cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-6);
    margin-top: var(--space-8);
}
.card {
    background: var(--color-bg-elevated);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
    box-shadow: var(--shadow-card);
    transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
    position: relative;
    overflow: hidden;
}
.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(168, 85, 247, 0.5), rgba(6, 182, 212, 0.5), transparent);
    opacity: 0;
    transition: opacity 0.3s ease;
}
.card:hover {
    transform: translateY(-4px);
    border-color: var(--color-border-strong);
    background: var(--color-bg-elevated-hover);
    box-shadow: var(--shadow-card-hover);
}
.card:hover::before { opacity: 1; }
.card h3 {
    font-size: 1.1875rem;
    font-weight: 600;
    margin-bottom: var(--space-3);
    color: var(--color-text);
    letter-spacing: -0.015em;
}
.card p {
    color: var(--color-text-muted);
    line-height: 1.7;
    font-size: 0.9375rem;
}

/* about/contact specific containers */
.about-content,
.contact-content {
    max-width: var(--container-narrow);
    margin: 0 auto;
}

/* ---------- Ad space ---------- */
.ad-space {
    background: var(--color-bg-elevated);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px dashed var(--color-border-strong);
    padding: var(--space-8);
    text-align: center;
    margin: var(--space-12) 0 0;
    border-radius: var(--radius-lg);
}
.ad-space p {
    color: var(--color-text-faint);
    font-size: 0.875rem;
}

/* ---------- Footer ---------- */
footer {
    background: rgba(8, 8, 12, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    color: var(--color-text-faint);
    text-align: center;
    padding: var(--space-10) 0;
    border-top: 1px solid var(--color-border);
    font-size: 0.875rem;
    margin-top: var(--space-12);
}
footer a {
    color: var(--color-text-muted);
    text-decoration: none;
    border-bottom: 1px solid var(--color-border-strong);
    transition: color 0.2s ease, border-color 0.2s ease;
}
footer a:hover {
    color: var(--color-text);
    border-bottom-color: var(--color-accent);
}

/* ---------- Blog list ---------- */
.blog-list {
    max-width: var(--container-narrow);
    margin: 0 auto;
    padding: var(--space-6) 0;
}
.blog-item {
    background: var(--color-bg-elevated);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-8);
    margin-bottom: var(--space-5);
    box-shadow: var(--shadow-card);
    transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
}
.blog-item:hover {
    transform: translateY(-4px);
    border-color: var(--color-border-strong);
    background: var(--color-bg-elevated-hover);
    box-shadow: var(--shadow-card-hover);
}
.blog-date {
    color: var(--color-text-faint);
    font-size: 0.8125rem;
    font-weight: 500;
    letter-spacing: 0.06em;
    margin-bottom: var(--space-3);
    font-variant-numeric: tabular-nums;
}
.blog-title {
    font-size: 1.4375rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: var(--space-3);
    text-decoration: none;
    display: block;
    letter-spacing: -0.02em;
    line-height: 1.3;
    transition: opacity 0.2s ease;
}
.blog-title:hover {
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}
.blog-excerpt {
    color: var(--color-text-muted);
    line-height: 1.7;
    margin-bottom: var(--space-5);
    font-size: 0.9375rem;
}
.read-more {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--color-accent);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9375rem;
    transition: gap 0.2s ease, color 0.2s ease;
}
.read-more:hover {
    gap: var(--space-3);
    color: #c084fc;
}
.blog-tags {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    margin-top: var(--space-5);
}
.tag {
    background: rgba(168, 85, 247, 0.1);
    border: 1px solid rgba(168, 85, 247, 0.22);
    padding: 4px 10px;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    color: rgba(192, 132, 252, 0.95);
    font-weight: 500;
    letter-spacing: 0.02em;
}

/* ---------- Post (single article) ---------- */
.post-container {
    max-width: var(--container-narrow);
    margin: 0 auto;
    padding: var(--space-12) var(--space-6) var(--space-20);
    position: relative;
    z-index: 1;
}
.post-header {
    margin-bottom: var(--space-12);
    padding-bottom: var(--space-8);
    border-bottom: 1px solid var(--color-border);
}
.post-date {
    color: var(--color-accent);
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    margin-bottom: var(--space-4);
}
.post-title {
    font-size: clamp(1.875rem, 4vw, 2.625rem);
    font-weight: 700;
    color: var(--color-text);
    letter-spacing: -0.03em;
    line-height: 1.15;
}
.post-content {
    line-height: 1.78;
    color: rgba(245, 245, 247, 0.88);
    font-size: 1.0625rem;
}
.post-content h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin: var(--space-12) 0 var(--space-4);
    color: var(--color-text);
    letter-spacing: -0.02em;
}
.post-content h3 {
    font-size: 1.1875rem;
    font-weight: 600;
    margin: var(--space-8) 0 var(--space-4);
    color: var(--color-text);
}
.post-content p { margin-bottom: var(--space-5); }
.post-content ul, .post-content ol {
    margin: var(--space-5) 0;
    padding-left: var(--space-6);
}
.post-content li { margin-bottom: var(--space-2); }
.post-content code {
    background: rgba(168, 85, 247, 0.13);
    padding: 0.15em 0.45em;
    border-radius: 5px;
    font-family: var(--font-mono);
    font-size: 0.88em;
    color: rgb(232, 217, 255);
    border: 1px solid rgba(168, 85, 247, 0.2);
}
.post-content pre {
    background: rgba(8, 8, 12, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    color: var(--color-text);
    padding: var(--space-6);
    border-radius: var(--radius-md);
    overflow-x: auto;
    margin: var(--space-6) 0;
    border: 1px solid var(--color-border);
    font-family: var(--font-mono);
    font-size: 0.875rem;
    line-height: 1.6;
}
.post-content pre code {
    background: none; padding: 0;
    color: var(--color-text); border: none;
}
.post-content a {
    color: var(--color-accent-2);
    text-decoration: none;
    border-bottom: 1px solid rgba(6, 182, 212, 0.3);
    transition: border-color 0.2s ease, color 0.2s ease;
}
.post-content a:hover {
    color: rgb(103, 232, 249);
    border-bottom-color: rgb(103, 232, 249);
}
.post-content strong {
    color: var(--color-text);
    font-weight: 600;
}
.post-footer {
    margin-top: var(--space-16);
    padding-top: var(--space-8);
    border-top: 1px solid var(--color-border);
}
.back-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--color-text-muted);
    text-decoration: none;
    font-weight: 500;
    transition: gap 0.2s ease, color 0.2s ease;
}
.back-link:hover {
    color: var(--color-accent);
    gap: var(--space-3);
}

/* ---------- Animations ---------- */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}
.fade-in {
    animation: fadeInUp 0.7s cubic-bezier(0.16, 1, 0.3, 1) backwards;
}
.fade-in-1 { animation-delay: 0s; }
.fade-in-2 { animation-delay: 0.1s; }
.fade-in-3 { animation-delay: 0.2s; }
.fade-in-4 { animation-delay: 0.3s; }

/* ---------- Premium interactions (effects.js) ---------- */

/* 粒子网络 canvas — 在视频背景之上 / 内容之下 */
#particle-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
    mix-blend-mode: screen;
    opacity: 0.85;
}

/* Scroll Reveal — 默认隐藏，进入视口加 .is-visible 触发 */
.reveal {
    opacity: 0;
    transform: translateY(28px);
    transition:
        opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
        transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
    will-change: opacity, transform;
}
.reveal.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* 鼠标光晕 cursor-glow（桌面） */
.cursor-glow {
    position: fixed;
    top: 0;
    left: 0;
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background:
        radial-gradient(circle, rgba(168, 85, 247, 0.18) 0%, rgba(168, 85, 247, 0.08) 30%, transparent 70%);
    pointer-events: none;
    z-index: 50;
    opacity: 0;
    transition: opacity 0.3s ease, width 0.3s ease, height 0.3s ease;
    mix-blend-mode: screen;
    will-change: transform;
}
.cursor-glow--hover {
    background:
        radial-gradient(circle, rgba(192, 132, 252, 0.32) 0%, rgba(6, 182, 212, 0.15) 35%, transparent 70%);
}

/* 3D 倾斜过渡（card 已经有 transition, 加上 transform 平滑） */
.card,
.blog-item {
    transition:
        transform 0.4s cubic-bezier(0.16, 1, 0.3, 1),
        border-color 0.3s ease,
        box-shadow 0.3s ease,
        background 0.3s ease;
    transform-style: preserve-3d;
}

/* 可变字重呼吸（Hero highlight 词） */
@keyframes weight-breath {
    0%, 100% { font-variation-settings: 'wght' 700; }
    50%      { font-variation-settings: 'wght' 350; }
}
.hero h1 .highlight {
    /* Inter 是 variable font，wght 在 100–900 之间 */
    animation: weight-breath 8s ease-in-out infinite;
    font-variation-settings: 'wght' 700;
}

/* 数字滚动统计 — 大字号 mono 数字 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: var(--space-6);
    margin-top: var(--space-10);
    padding: var(--space-10) var(--space-6);
    background: var(--color-bg-elevated);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
}
.stat-cell {
    text-align: center;
}
.stat-num {
    font-family: var(--font-mono);
    font-size: clamp(2rem, 4vw, 2.75rem);
    font-weight: 700;
    line-height: 1;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    letter-spacing: -0.02em;
    font-variant-numeric: tabular-nums;
}
.stat-label {
    margin-top: var(--space-3);
    font-size: 0.8125rem;
    font-weight: 500;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--color-text-muted);
}

/* 隐藏粒子背景 在 prefers-reduced-motion 下 */
@media (prefers-reduced-motion: reduce) {
    .reveal { opacity: 1; transform: none; transition: none; }
    .hero h1 .highlight { animation: none; }
    .cursor-glow { display: none; }
    #particle-canvas { display: none; }
}

/* 移动端不显示粒子 + 不显示光晕 */
@media (max-width: 768px) {
    #particle-canvas { display: none; }
    .cursor-glow { display: none; }
    /* 移动端卡片不要 3D 倾斜 */
    .card, .blog-item { transform: none !important; }
}

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
    .nav-links { display: none; }
    .lang-switcher { margin-left: 0; }
    .container { padding: 0 var(--space-4); }
    .hero { padding: var(--space-20) 0 var(--space-16); }
    .page-hero { padding: var(--space-12) 0 var(--space-8); }
    .post-container { padding: var(--space-8) var(--space-4) var(--space-16); }
    .card, .blog-item { padding: var(--space-6); }
    .hero-actions { flex-direction: column; align-items: stretch; }
    .blog-title { font-size: 1.25rem; }
}