/* ============================================================
   RobotWAI v2 — 专业级设计系统
   设计语言：参考 Linear / Vercel / Notion / Stripe
   ============================================================ */

/* ---------- Design Tokens ---------- */
:root {
  /* 品牌色 */
  --c-brand:        #6366F1;
  --c-brand-light:  #818CF8;
  --c-brand-dark:   #4F46E5;
  --c-accent:       #8B5CF6;

  /* 功能色 */
  --c-success:      #10B981;
  --c-warning:      #F59E0B;
  --c-error:        #EF4444;
  --c-info:         #3B82F6;

  /* 中性色（Slate 灰度系统） */
  --c-slate-50:     #F8FAFC;
  --c-slate-100:    #F1F5F9;
  --c-slate-200:    #E2E8F0;
  --c-slate-300:    #CBD5E1;
  --c-slate-400:    #94A3B8;
  --c-slate-500:    #64748B;
  --c-slate-600:    #475569;
  --c-slate-700:    #334155;
  --c-slate-800:    #1E293B;
  --c-slate-900:    #0F172A;

  /* 语义化映射 */
  --bg-body:        var(--c-slate-50);
  --bg-card:        #FFFFFF;
  --bg-elevated:    #FFFFFF;
  --border:         var(--c-slate-200);
  --border-hover:   var(--c-slate-300);
  --text-primary:   var(--c-slate-900);
  --text-secondary: var(--c-slate-500);
  --text-muted:     var(--c-slate-400);

  /* 字体 */
  --font:           'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono:      'JetBrains Mono', 'SF Mono', Consolas, monospace;

  /* 字号 */
  --ts-xs:          .75rem;    /* 12px */
  --ts-sm:          .875rem;   /* 14px */
  --ts-base:        1rem;      /* 16px */
  --ts-lg:          1.125rem;  /* 18px */
  --ts-xl:          1.25rem;   /* 20px */
  --ts-2xl:         1.5rem;    /* 24px */
  --ts-3xl:         2rem;      /* 32px */
  --ts-4xl:         3rem;      /* 48px */
  --ts-hero:        clamp(2.5rem, 5vw, 4rem);

  /* 行高 */
  --lh-tight:       1.15;
  --lh-normal:      1.6;
  --lh-relaxed:     1.7;

  /* 间距（优化后更宽松的间距系统） */
  --sp-1:           .25rem;    /* 4px */
  --sp-2:           .5rem;     /* 8px */
  --sp-3:           .75rem;    /* 12px */
  --sp-4:           1rem;      /* 16px */
  --sp-5:           1.5rem;    /* 24px */
  --sp-6:           2rem;      /* 32px */
  --sp-7:           3rem;      /* 48px */
  --sp-8:           4rem;      /* 64px */
  --sp-9:           5rem;      /* 80px */
  --sp-10:          6rem;      /* 96px */

  /* 圆角 */
  --r-sm:           6px;
  --r-md:           10px;
  --r-lg:           14px;
  --r-xl:           20px;
  --r-full:         9999px;

  /* 阴影（分层系统） */
  --sh-xs:          0 1px 2px rgba(15,23,42,.04);
  --sh-sm:          0 2px 4px rgba(15,23,42,.04), 0 1px 2px rgba(15,23,42,.06);
  --sh-md:          0 4px 12px rgba(15,23,42,.06), 0 1px 3px rgba(15,23,42,.08);
  --sh-lg:          0 10px 30px rgba(15,23,42,.08), 0 2px 8px rgba(15,23,42,.08);
  --sh-xl:          0 20px 50px rgba(15,23,42,.1), 0 4px 12px rgba(15,23,42,.08);
  --sh-glow:        0 0 40px rgba(99,102,241,.15);

  /* 过渡 */
  --ease-out:       cubic-bezier(.16,1,.3,1);
  --ease-in-out:    cubic-bezier(.65,0,.35,1);
  --dur-fast:       150ms;
  --dur-normal:     250ms;
  --dur-slow:       400ms;

  /* 侧边栏 */
  --sidebar-w:       256px;
  --sidebar-collapsed: 72px;
}

/* ---------- Reset & Base ---------- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
body {
  font-family: var(--font); font-size: var(--ts-base); line-height: var(--lh-normal);
  color: var(--text-primary); background: var(--bg-body); overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
img, svg { display: block; max-width: 100%; }
ul { list-style: none; }

.container {
  width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 var(--sp-6);
}

/* ========== SIDEBAR ========== */
.sidebar {
  position: fixed; top: 0; left: 0; bottom: 0; z-index: 100;
  width: var(--sidebar-w); background: var(--bg-card);
  border-right: 1px solid var(--border);
  display: flex; flex-direction: column;
  transition: width var(--dur-normal) var(--ease-out); overflow: hidden;
}
.sidebar.collapsed { width: var(--sidebar-collapsed); }

.sidebar-brand {
  padding: var(--sp-5) var(--sp-4); border-bottom: 1px solid var(--border);
}
.brand-link {
  display: flex; align-items: center; gap: var(--sp-3); min-width: 0;
  cursor: pointer; transition: opacity var(--dur-fast);
}
.brand-link:hover { opacity: .8; }
.brand-icon { width: 32px; height: 32px; flex-shrink: 0; border-radius: var(--r-md); }
.brand-text {
  font-size: var(--ts-xl); font-weight: 700; letter-spacing: -.02em;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  background: linear-gradient(135deg, var(--c-brand), var(--c-accent));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.sidebar.collapsed .brand-text { display: none; }

/* Nav */
.sidebar-nav { flex: 1; padding: var(--sp-3) 0; overflow-y: auto; }
.nav-list { display: flex; flex-direction: column; gap: 2px; padding: 0 var(--sp-3); }
.nav-item { border-radius: var(--r-sm); }
.nav-link {
  display: flex; align-items: center; gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-3); border-radius: var(--r-sm);
  color: var(--text-secondary); font-size: var(--ts-sm); font-weight: 500;
  transition: all var(--dur-fast) ease;
}
.nav-link:hover { background: var(--c-slate-50); color: var(--text-primary); }
.nav-item.active > .nav-link {
  background: rgba(99,102,241,.07); color: var(--c-brand);
  box-shadow: inset 3px 0 0 var(--c-brand);
}
.nav-icon { width: 20px; height: 20px; flex-shrink: 0; opacity: .7; display: inline-flex; align-items: center; justify-content: center; }
.nav-item.active .nav-icon { opacity: 1; }
.nav-label { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.sidebar.collapsed .nav-label { display: none; }

/* ========== MAIN CONTENT ========== */
.main {
  margin-left: var(--sidebar-w);
  transition: margin-left var(--dur-normal) var(--ease-out);
  min-height: 100vh;
}
.sidebar.collapsed ~ .main { margin-left: var(--sidebar-collapsed); }

/* ========== HERO ========== */
.hero {
  position: relative; overflow: hidden;
  min-height: 52vh;
  display: flex; align-items: center;
  background: linear-gradient(135deg, #4338CA 0%, #6366F1 30%, #8B5CF6 70%, #A78BFA 100%);
  padding: var(--sp-5) var(--sp-6);
  color: #fff;
}

.hero-bg { position: absolute; inset: 0; pointer-events: none; overflow: hidden; }
.hero-glow {
  position: absolute; border-radius: 50%; filter: blur(80px); opacity: .4;
}
.hero-glow--1 { width: 500px; height: 500px; right: -100px; top: -80px; background: #818CF8; }
.hero-glow--2 { width: 400px; height: 400px; left: -60px; bottom: -120px; background: #C084FC; opacity: .25; }
.hero-grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.03) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
}

.hero-inner {
  position: relative; max-width: 1200px; margin: 0 auto; width: 100%;
  display: grid; grid-template-columns: 1fr 340px; gap: var(--sp-6); align-items: center;
}

/* Hero 文字内容 — 更紧凑的信息层级 */
.hero-content { padding-right: var(--sp-2); }

.hero-title {
  font-size: var(--ts-hero); font-weight: 800; line-height: 1.1;
  letter-spacing: -.03em; margin-bottom: var(--sp-2);
}
.title-brand {
  display: inline-block;
  background: linear-gradient(135deg, #FDE68A 0%, #F59E0B 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: var(--ts-lg); font-weight: 500; letter-spacing: .15em;
  opacity: .75; margin-bottom: var(--sp-2);
}

.hero-desc {
  font-size: var(--ts-lg); line-height: var(--lh-relaxed);
  opacity: .9; max-width: 480px; margin-bottom: var(--sp-1);
  font-weight: 400;
}

.hero-tagline {
  font-size: var(--ts-base); letter-spacing: .2em;
  opacity: .55; margin-bottom: var(--sp-4);
  font-weight: 300;
}

.hero-actions { display: flex; gap: var(--sp-3); flex-wrap: wrap; margin-bottom: var(--sp-3); }

.btn {
  display: inline-flex; align-items: center; gap: var(--sp-2);
  padding: 13px 28px; border-radius: var(--r-md);
  font-size: var(--ts-sm); font-weight: 600;
  transition: all var(--dur-fast) ease;
}
.btn--primary {
  background: #fff; color: var(--c-brand-dark);
  box-shadow: 0 4px 14px rgba(0,0,0,.15);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,.22); }
.btn--ghost {
  background: rgba(255,255,255,.1); color: #fff;
  border: 1px solid rgba(255,255,255,.2);
}
.btn--ghost:hover { background: rgba(255,255,255,.18); }

.hero-stats {
  display: flex; align-items: center; justify-content: flex-start;
  padding-top: var(--sp-3); border-top: 1px solid rgba(255,255,255,.14);
}
.stat-flow {
  font-size: var(--ts-xs); letter-spacing: .05em;
  opacity: .55; font-weight: 400;
}

/* Hero 内精简版精神股东 */
.hero-supporters {
  display: flex; flex-direction: column; align-items: flex-start;
  gap: var(--sp-2); padding-top: var(--sp-3);
}
.supporters-label {
  font-size: var(--ts-xs); letter-spacing: .06em;
  opacity: .45; font-weight: 500;
}
.supporters-mini {
  display: flex; align-items: center; gap: var(--sp-2); flex-wrap: wrap;
}
.mini-avatar {
  width: 28px; height: 28px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 9px; font-weight: 700; color: #fff;
  background: hsl(var(--hue, 220), 65%, 55%);
  border: 2px solid rgba(255,255,255,.2);
  transition: transform var(--dur-fast), box-shadow var(--dur-fast);
  cursor: pointer;
}
.mini-avatar:hover { transform: scale(1.15); box-shadow: 0 0 12px hsla(var(--hue, 220), 65%, 55%, .4); }
.mini-avatar.mini-more {
  background: rgba(255,255,255,.15);
  color: rgba(255,255,255,.7);
  border-style: dashed;
  font-size: 9px;
}

/* Hero Visual — 右侧机器人区域 */
.hero-visual { display: flex; justify-content: center; align-items: center; }
.visual-card {
  position: relative; width: 240px; height: 240px;
  display: flex; align-items: center; justify-content: center;
}
.visual-inner {
  width: 150px; height: 150px; border-radius: var(--r-xl);
  background: rgba(255,255,255,.12); backdrop-filter: blur(12px);
  border: 1px solid rgba(255,255,255,.18);
  display: flex; align-items: center; justify-content: center;
  animation: float-card 6s ease-in-out infinite;
}
@keyframes float-card {
  0%,100%{transform:translateY(0)} 50%{transform:translateY(-12px)}
}
.robot-face { width: 110px; height: 110px; }

.visual-ring {
  position: absolute; border-radius: 50%; border: 1px solid rgba(255,255,255,.1);
  animation: ring-pulse 4s ease-in-out infinite;
}
.visual-ring--1 { width: 190px; height: 190px; animation-delay: 0s; }
.visual-ring--2 { width: 220px; height: 220px; animation-delay: 1.5s; }
@keyframes ring-pulse {
  0%,100%{transform:scale(1); opacity:.4} 50%{transform:scale(1.05); opacity:.15}
}

.visual-dots { position: absolute; inset: 0; }
.visual-dots i {
  position: absolute; width: 4px; height: 4px; border-radius: 50%;
  background: rgba(255,255,255,.4);
  animation: twinkle 3s ease-in-out infinite;
}
.visual-dots i:nth-child(1){top:10%;left:20%;animation-delay:0s}
.visual-dots i:nth-child(2){top:15%;right:15%;animation-delay:.5s}
.visual-dots i:nth-child(3){bottom:20%;left:10%;animation-delay:1s}
.visual-dots i:nth-child(4){bottom:15%;right:22%;animation-delay:1.5s}
.visual-dots i:nth-child(5){top:45%;left:-5%;animation-delay:2s}
.visual-dots i:nth-child(6){top:55%;right:-3%;animation-delay:2.5s}
@keyframes twinkle { 0%,100%{opacity:.4} 50%{opacity:0} }

/* ========== SECTION COMMON ========== */
.section { padding: var(--sp-5) 0; }
.section-header { text-align: center; margin-bottom: var(--sp-4); }
.section-label {
  display: inline-block; font-size: var(--ts-xs); font-weight: 600;
  letter-spacing: .08em; text-transform: uppercase; color: var(--c-brand);
  margin-bottom: var(--sp-2);
}
.section-title {
  font-size: var(--ts-3xl); font-weight: 750; letter-spacing: -.02em;
  color: var(--text-primary); margin-bottom: var(--sp-2);
}
.section-desc {
  font-size: var(--ts-base); color: var(--text-secondary);
  max-width: 520px; margin: 0 auto;
}

/* ========== TIMELINE (Updates) ========== */
.section--updates { background: var(--bg-card); }

.timeline {
  display: flex; flex-direction: column; gap: var(--sp-2);
  max-width: 760px; margin: 0 auto;
}

.timeline-card {
  display: grid; grid-template-columns: auto 1fr; gap: var(--sp-3);
  padding: var(--sp-3) var(--sp-4); border-radius: var(--r-lg);
  background: var(--bg-body); border: 1px solid var(--border);
  transition: all var(--dur-normal) var(--ease-out);
}
.timeline-card:hover {
  border-color: var(--c-brand-light);
  box-shadow: var(--sh-md);
  transform: translateY(-2px);
}

.timeline-status {
  display: inline-flex; align-items: center; gap: var(--sp-1);
  padding: 4px 10px; border-radius: var(--r-full);
  font-size: var(--ts-xs); font-weight: 600; white-space: nowrap;
  height: fit-content;
}
.status--active  { background: rgba(16,185,129,.08); color: var(--c-success); }
.status--done    { background: rgba(59,130,246,.08); color: var(--c-info); }
.status--pending { background: rgba(245,158,11,.08); color: var(--c-warning); }

.timeline-title {
  font-size: var(--ts-lg); font-weight: 650;
  color: var(--text-primary); margin-bottom: var(--sp-1);
}
.timeline-desc {
  font-size: var(--ts-sm); color: var(--text-secondary);
  line-height: var(--lh-relaxed); margin-bottom: var(--sp-2);
}
.timeline-tags { display: flex; flex-wrap: wrap; gap: var(--sp-2); }
.timeline-tags span {
  padding: 3px 10px; border-radius: var(--r-full);
  background: var(--c-slate-100); color: var(--text-secondary);
  font-size: var(--ts-xs); font-weight: 500;
}

/* ========== PROJECTS ========== */
.section--projects { background: var(--bg-body); } /* 与 updates 形成交替背景 */

.filter-bar {
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--sp-5); margin-bottom: var(--sp-5); flex-wrap: wrap;
}
.search-input-wrap {
  display: flex; align-items: center; gap: var(--sp-2);
  padding: 11px 18px; background: var(--bg-card);
  border: 1px solid var(--border); border-radius: var(--r-lg);
  transition: all var(--dur-fast);
  min-width: 260px;
}
.search-input-wrap:focus-within {
  border-color: var(--c-brand);
  box-shadow: 0 0 0 3px rgba(99,102,241,.1);
}
.search-icon { color: var(--text-muted); flex-shrink: 0; }
.search-input {
  border: none; outline: none; background: transparent;
  font-size: var(--ts-sm); color: var(--text-primary); width: 100%;
}
.search-input::placeholder { color: var(--text-muted); }

.filter-group { display: flex; gap: var(--sp-2); flex-wrap: wrap; }
.filter-chip {
  padding: 8px 18px; border-radius: var(--r-full);
  font-size: var(--ts-xs); font-weight: 500;
  background: var(--bg-card); border: 1px solid var(--border);
  color: var(--text-secondary); cursor: pointer;
  transition: all var(--dur-fast);
}
.filter-chip:hover { border-color: var(--c-brand-light); color: var(--c-brand); }
.filter-chip.active { background: var(--c-brand); border-color: var(--c-brand); color: #fff; }

/* Project Cards Grid */
.projects-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: var(--sp-4);
}

.project-card {
  border-radius: var(--r-lg); overflow: hidden;
  background: var(--bg-card); border: 1px solid var(--border);
  transition: all var(--dur-normal) var(--ease-out);
}
.project-card:hover {
  border-color: var(--c-brand-light);
  box-shadow: var(--sh-xl);
  transform: translateY(-4px);
}

.card-top { position: relative; height: 140px; overflow: hidden; }
.card-bg {
  position: absolute; inset: 0;
  transition: transform var(--dur-slow) var(--ease-out);
}
.project-card:hover .card-bg { transform: scale(1.05); }
.card-bg--chat   { background: linear-gradient(135deg, #4338CA, #6366F1); }
.card-bg--image  { background: linear-gradient(135deg, #7C3AED, #A78BFA); }
.card-bg--code   { background: linear-gradient(135deg, #059669, #34D399); }
.card-bg--voice  { background: linear-gradient(135deg, #D97706, #FBBF24); }
.card-bg--write  { background: linear-gradient(135deg, #DB2777, #F472B6); }
.card-bg--data   { background: linear-gradient(135deg, #0284C7, #38BDF8); }

.card-pattern {
  position: absolute; inset: 0;
  background-image:
    radial-gradient(circle at 30% 40%, rgba(255,255,255,.08) 0%, transparent 50%),
    radial-gradient(circle at 70% 70%, rgba(255,255,255,.06) 0%, transparent 45%);
}

.card-icon-wrap {
  position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
  width: 52px; height: 52px; border-radius: var(--r-lg);
  background: rgba(255,255,255,.12); backdrop-filter: blur(8px);
  border: 1px solid rgba(255,255,255,.2);
  display: flex; align-items: center; justify-content: center;
  transition: all var(--dur-normal) var(--ease-out);
}
.project-card:hover .card-icon-wrap {
  transform: translate(-50%, -50%) scale(1.08);
  background: rgba(255,255,255,.18);
}
.card-icon { width: 26px; height: 26px; }

.card-body { padding: var(--sp-4); }
.card-title { font-size: var(--ts-lg); font-weight: 650; color: var(--text-primary); margin-bottom: var(--sp-1); }
.card-desc { font-size: var(--ts-sm); color: var(--text-secondary); line-height: var(--lh-relaxed); margin-bottom: var(--sp-3); }
.card-tags { display: flex; flex-wrap: wrap; gap: var(--sp-2); margin-bottom: var(--sp-3); }
.card-tags span {
  padding: 4px 12px; border-radius: var(--r-full);
  background: var(--c-slate-50); color: var(--text-secondary);
  font-size: var(--ts-xs); font-weight: 500;
}
.card-btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--sp-2);
  width: 100%; padding: 11px 0; border-radius: var(--r-md);
  background: var(--c-brand); color: #fff;
  font-size: var(--ts-sm); font-weight: 600;
  transition: all var(--dur-fast);
}
.card-btn:hover { background: var(--c-brand-dark); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(99,102,241,.3); }

/* ========== ABOUT - 版本二：极简极客 ========== */
.section--about { background: var(--bg-card); }

.about-content {
  max-width: 600px; margin: 0 auto;
  display: flex; flex-direction: column;
  gap: 0;
}

/* 内容块：统一细线分隔 */
.about-block {
  padding: var(--sp-2) 0;
  border-top: 1px solid var(--border);
}
.about-block:first-of-type { border-top: none; }
.about-subtitle {
  font-size: var(--ts-base); font-weight: 600;
  color: var(--text-primary); margin-bottom: var(--sp-2);
}

/* 工具链代码行 */
.about-body-code {
  font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
  font-size: var(--ts-sm); color: var(--c-slate-500);
  background: var(--c-slate-50); padding: var(--sp-2) var(--sp-3);
  border-radius: var(--r-sm); letter-spacing: .01em;
  margin-bottom: var(--sp-2);
}
.about-body {
  font-size: var(--ts-sm); color: var(--text-secondary);
  line-height: 1.7;
}

/* 态度模块：独立视觉块 */
.about-block--motto {
  text-align: center; border-top: none; border-bottom: none;
  padding: var(--sp-3) 0; position: relative;
}
.about-block--motto::before,
.about-block--motto::after {
  content: ''; display: block;
  height: 1px; width: 48px;
  background: linear-gradient(90deg, transparent, var(--border), transparent);
  margin: 0 auto;
}
.about-block--motto::before { margin-bottom: var(--sp-2); }
.about-block--motto::after { margin-top: var(--sp-2); }
.about-motto {
  font-size: clamp(1rem, 2.5vw, 1.15rem);
  font-weight: 650; letter-spacing: .15em;
  color: var(--c-brand);
  white-space: nowrap;
}

/* 列表 */
.about-list {
  list-style: none; padding: 0; margin: 0;
  display: flex; flex-direction: column; gap: 0;
}
.about-list li {
  font-size: var(--ts-sm); color: var(--text-secondary);
  line-height: 1.8; padding-left: var(--sp-3);
  position: relative;
}
.about-list li::before {
  content: ''; position: absolute; left: 0; top: .7em;
  width: 4px; height: 4px; border-radius: 50%;
  background: var(--c-brand); opacity: .45;
}

/* 联系方式：小红书图片 */
.about-block--contact {
  text-align: center; border-top: none;
  padding: var(--sp-3) 0 0;
}
.contact-image {
  max-width: 280px; width: 100%;
  border-radius: var(--r-lg);
  box-shadow: var(--sh-md);
  display: block; margin: 0 auto;
}

/* 结尾：英文收尾 */
.about-closing {
  padding: var(--sp-5) 0 0;
  text-align: center;
}
.about-closing p {
  font-size: var(--ts-sm); color: var(--c-slate-400);
  font-style: italic; line-height: 1.7;
}

/* ========== FOOTER ========== */
.footer {
  background: var(--c-slate-900); color: var(--c-slate-500);
  padding: var(--sp-4) 0; margin-top: 0;
}
.footer-inner { display: flex; justify-content: center; align-items: center; }
.footer-copy { font-size: var(--ts-xs); letter-spacing: .02em; }

/* ========== REVEAL ANIMATION ========== */
.reveal {
  opacity: 0; transform: translateY(24px);
  transition: opacity .6s var(--ease-out), transform .6s var(--ease-out);
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ========== RESPONSIVE ========== */

/* 平板：Hero 单列 + 关于单列 */
@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center; gap: var(--sp-5);
  }
  .hero-content { order: 1; }
  .hero-visual { order: 0; }
  .hero-desc { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }
  .hero-stats { justify-content: center; }
  .hero-supporters { align-items: center; }
  .visual-card { width: 200px; height: 200px; }
  .visual-inner { width: 130px; height: 130px; }
  .robot-face { width: 100px; height: 100px; }
  .about-content { gap: 0; }
  .about-block { padding: var(--sp-2) 0; }
  .contact-card { flex-direction: column; text-align: center; padding: var(--sp-3); }
  .projects-grid { grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); }
}

/* 手机：侧边栏变顶栏 + 单列布局 */
@media (max-width: 768px) {
  :root { --sidebar-w: 0; }
  .sidebar {
    position: fixed; top: 0; left: 0; right: 0; bottom: auto;
    width: 100%; height: auto; flex-direction: row;
    border-right: none; border-bottom: 1px solid var(--border);
    padding: 0 var(--sp-4);
    z-index: 110;
  }
  .sidebar.collapsed { width: 100%; }
  .sidebar-brand { padding: var(--sp-3) 0; border-bottom: none; border-right: 1px solid var(--border); padding-right: var(--sp-4); }
  .sidebar-nav { padding: var(--sp-2) 0; flex: 1; }
  .nav-list { flex-direction: row; gap: 0; padding: 0; }
  .nav-item { border-bottom: 2px solid transparent; }
  .nav-item.active > .nav-link { box-shadow: none; border-bottom-color: var(--c-brand); background: none; }
  .nav-label { display: none; }
  .nav-icon { width: 22px; height: 22px; }
  .nav-link { padding: var(--sp-2) var(--sp-3); }
  .main { margin-left: 0; }
  .hero { min-height: auto; padding: var(--sp-6) var(--sp-4); }
  .section { padding: var(--sp-6) 0; }
  .container { padding: 0 var(--sp-4); }
  .projects-grid { grid-template-columns: 1fr; }
  .filter-bar { flex-direction: column; align-items: stretch; }
  .search-input-wrap { min-width: auto; }
  .filter-group { justify-content: flex-start; }
  .timeline-card { grid-template-columns: 1fr; gap: var(--sp-3); padding: var(--sp-5); }
  .timeline-status { align-self: flex-start; }
  .hero-glow--1, .hero-glow--2 { opacity: .2; }
}

/* 小屏手机 */
@media (max-width: 480px) {
  .hero-title { font-size: clamp(1.75rem, 7vw, 2.5rem); }
  .hero-subtitle { font-size: var(--ts-base); letter-spacing: .1em; }
  .btn { padding: 11px 20px; font-size: var(--ts-xs); }
  .hero-stats { flex-direction: column; gap: 0; align-items: flex-start; }
  .avatar-row { gap: var(--sp-3); }
  .avatar-circle { width: 44px; height: 44px; font-size: var(--ts-xs); }
  .section-header { margin-bottom: var(--sp-4); }
  .card-body { padding: var(--sp-4); }
  .about-content { gap: 0; }
  .about-block { padding: var(--sp-2) 0; }
}