/* =============================================================
   快传 (KuaiChuan) — HyperOS White Minimal
   ============================================================= */

/* ---------- CSS Custom Properties ---------- */
:root {
  /* HyperOS 配色 */
  --bg-page: #f2f3f7;
  --bg-card: #ffffff;
  --bg-hover: #f5f5f5;
  --bg-active: #e8e8e8;
  --bg-input: #f5f5f5;

  --accent: #0A84FF;
  --accent-hover: #0071E3;
  --accent-light: #E8F2FF;
  --accent-gradient: linear-gradient(135deg, #0A84FF 0%, #5856D6 100%);
  --success: #34C759;
  --success-light: #E8F8ED;
  --warning: #FF9500;
  --error: #FF3B30;

  --text-primary: #1c1c1e;
  --text-secondary: #8e8e93;
  --text-muted: #aeaeb2;
  --text-inverse: #ffffff;

  --border: #e5e5e7;
  --border-light: #f0f0f2;
  --separator: #e5e5e7;

  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 4px 16px rgba(0,0,0,0.06);
  --shadow-elevated: 0 4px 12px rgba(0,0,0,0.08), 0 12px 32px rgba(0,0,0,0.06);
  --shadow-btn: 0 2px 8px rgba(10,132,255,0.25);

  --font: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'PingFang SC', 'Helvetica Neue', system-ui, sans-serif;

  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.45s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ---------- Reset & Base ---------- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:16px;-webkit-text-size-adjust:100%}
body{
  font-family:var(--font);
  background:var(--bg-page);
  color:var(--text-primary);
  min-height:100vh;
  line-height:1.5;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  padding-bottom:env(safe-area-inset-bottom);
}

/* ---------- App Container ---------- */
#app{
  max-width:640px;
  margin:0 auto;
  padding:0 16px 40px;
  min-height:100vh;
  display:flex;
  flex-direction:column;
}

/* =============================================================
   Header — HyperOS 风格
   ============================================================= */
.header{
  padding:18px 20px 12px;
  margin:0 -16px 16px;
  background:var(--bg-card);
  border-bottom:1px solid var(--border-light);
  position:sticky;
  top:0;
  z-index:10;
}
.header-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
}
.brand{display:flex;align-items:center;gap:12px}
.brand-icon{
  width:36px;height:36px;
  background:var(--accent-gradient);
  border-radius:10px;
  display:flex;align-items:center;justify-content:center;
  font-size:18px;
  color:#fff;
}
.brand-text h1{
  font-size:18px;font-weight:700;letter-spacing:-0.3px;
  color:var(--text-primary);
  line-height:1.2;
}
.brand-sub{font-size:12px;color:var(--text-secondary);font-weight:400}

/* Status Badge */
.status-badge{
  display:flex;align-items:center;gap:5px;
  padding:4px 12px;
  border-radius:20px;
  background:var(--bg-input);
  font-size:12px;font-weight:500;color:var(--text-secondary);
  white-space:nowrap;
  transition:var(--transition);
}
.status-dot{
  width:7px;height:7px;border-radius:50%;
  background:#c7c7cc;
  transition:var(--transition);
}
.status-badge.connected{background:var(--success-light);color:#34A853}
.status-badge.connected .status-dot{background:var(--success)}
.status-badge.connecting{background:#FFF3E0;color:#E65100}
.status-badge.connecting .status-dot{background:var(--warning);animation:pulse-dot 1s ease-in-out infinite}
.status-badge.error{background:#FFEBEE;color:#C62828}
.status-badge.error .status-dot{background:var(--error)}
@keyframes pulse-dot{0%,100%{opacity:1}50%{opacity:0.4}}

/* =============================================================
   Card — HyperOS 白色卡片
   ============================================================= */
.card{
  background:var(--bg-card);
  border-radius:var(--radius-lg);
  box-shadow:var(--shadow-card);
  margin-bottom:14px;
  overflow:hidden;
}
.card-body{padding:20px}

/* =============================================================
   Connection Panel — HyperOS 双列布局
   ============================================================= */
.connection-grid{
  display:flex;
  flex-direction:column;
  gap:12px;
}
.conn-option{
  text-align:center;
  padding:20px 16px;
  border-radius:var(--radius-md);
  background:var(--bg-page);
  transition:var(--transition);
  cursor:default;
}
.conn-option:active{background:var(--bg-active)}
.conn-icon-wrap{
  width:48px;height:48px;border-radius:14px;
  display:flex;align-items:center;justify-content:center;
  margin:0 auto 10px;
}
.conn-icon{font-size:22px}
.conn-title{font-size:16px;font-weight:600;margin-bottom:2px}
.conn-desc{font-size:13px;color:var(--text-secondary);margin-bottom:14px}
.conn-divider{
  display:flex;align-items:center;gap:12px;
  color:var(--text-muted);font-size:12px;padding:0 4px;
  margin:0 0 2px;
}
.conn-divider::before,.conn-divider::after{
  content:'';flex:1;height:1px;
  background:var(--separator);
}

/* ---- Input ---- */
.input-row{display:flex;gap:8px}
.input{
  flex:1;padding:11px 14px;font-size:15px;
  font-family:var(--font);
  background:var(--bg-input);
  border:1.5px solid transparent;
  border-radius:var(--radius-sm);
  color:var(--text-primary);
  outline:none;
  transition:var(--transition);
}
.input:focus{
  border-color:var(--accent);
  background:var(--bg-card);
  box-shadow:0 0 0 3px rgba(10,132,255,0.12);
}
.input::placeholder{color:var(--text-muted)}

/* ---- Peer ID Display ---- */
.peer-id-box{margin-top:14px;padding:16px;background:var(--accent-light);border-radius:var(--radius-sm)}
.peer-label{font-size:11px;color:var(--text-secondary);text-transform:uppercase;letter-spacing:0.8px;margin-bottom:8px;display:block}
.peer-id-row{display:flex;align-items:center;gap:8px;justify-content:center}
.peer-id{
  font-size:24px;font-weight:700;letter-spacing:3px;
  color:var(--accent);
  font-family:'SF Mono','Menlo','Monaco',monospace;
}
.btn-icon{
  width:34px;height:34px;border-radius:9px;border:none;
  background:var(--bg-card);cursor:pointer;font-size:15px;display:flex;
  align-items:center;justify-content:center;
  transition:var(--transition);color:var(--text-primary);
  box-shadow:0 1px 3px rgba(0,0,0,0.06);
}
.btn-icon:hover{background:var(--bg-hover);transform:scale(1.04)}
.btn-icon:active{transform:scale(0.94)}
.peer-hint{font-size:13px;color:var(--text-secondary);margin-top:8px;text-align:center}
.waiting-dots{display:flex;gap:5px;justify-content:center;margin-top:10px}
.waiting-dots span{
  width:6px;height:6px;border-radius:50%;
  background:var(--accent);
  animation:wait-bounce 1.4s ease-in-out infinite;
  opacity:0.4;
}
.waiting-dots span:nth-child(2){animation-delay:0.2s;opacity:0.6}
.waiting-dots span:nth-child(3){animation-delay:0.4s;opacity:0.8}
@keyframes wait-bounce{0%,60%,100%{transform:translateY(0)}30%{transform:translateY(-7px)}}

/* =============================================================
   Buttons — HyperOS 风格
   ============================================================= */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:6px;
  padding:10px 22px;font-size:14px;font-weight:600;
  font-family:var(--font);
  border:none;border-radius:var(--radius-sm);
  cursor:pointer;transition:var(--transition);
  white-space:nowrap;user-select:none;
  text-decoration:none;
}
.btn:active{transform:scale(0.96)}
.btn-primary{
  background:var(--accent);
  color:var(--text-inverse);
  box-shadow:var(--shadow-btn);
}
.btn-primary:hover{background:var(--accent-hover)}
.btn-secondary{
  background:var(--bg-input);
  color:var(--text-primary);
}
.btn-secondary:hover{background:var(--bg-hover)}
.btn-ghost{
  background:transparent;color:var(--text-secondary);
  padding:6px 12px;font-size:13px;border-radius:8px;
}
.btn-ghost:hover{background:var(--bg-hover);color:var(--text-primary)}
.btn-block{width:100%;margin-top:8px;padding:12px 20px}
.btn-sm{padding:6px 12px;font-size:13px;border-radius:8px}
.btn:disabled{opacity:0.5;cursor:not-allowed;transform:none!important}

/* =============================================================
   Connected Panel
   ============================================================= */
.conn-bar{
  display:flex;align-items:center;justify-content:space-between;
  padding:12px 20px;
  background:var(--success-light);
  font-size:13px;color:var(--text-primary);
}
.conn-bar-left{display:flex;align-items:center;gap:7px}
.conn-bar-dot{width:7px;height:7px;border-radius:50%;background:var(--success)}
.conn-bar-id{color:var(--accent);font-size:13px;font-weight:600}

/* =============================================================
   Drop Zone
   ============================================================= */
.drop-zone{
  margin:14px 20px;
  border:2px dashed var(--border);
  border-radius:var(--radius-md);
  transition:var(--transition);
  cursor:pointer;
}
.drop-zone:hover{border-color:var(--accent);background:var(--accent-light)}
.drop-zone.drag-over{
  border-color:var(--accent);
  background:var(--accent-light);
  transform:scale(1.01);
}
.drop-inner{
  padding:28px 16px;text-align:center;
}
.drop-icon-wrap{
  width:56px;height:56px;border-radius:50%;
  background:var(--accent-light);
  display:flex;align-items:center;justify-content:center;
  margin:0 auto 10px;
  color:var(--accent);
}
.drop-icon-svg{transition:var(--transition-spring);width:40px;height:40px}
.drop-zone.drag-over .drop-icon-svg{transform:translateY(-4px);color:var(--accent)}
.drop-title{font-size:15px;font-weight:600;margin-bottom:2px}
.drop-hint{font-size:13px;color:var(--text-secondary);margin-bottom:12px}

/* =============================================================
   Section Blocks
   ============================================================= */
.section-block{
  padding:0 20px 14px;
}
.section-head{
  display:flex;align-items:center;justify-content:space-between;
  padding:10px 0 8px;
  border-bottom:1px solid var(--border-light);
  margin-bottom:8px;
}
.section-title{font-size:15px;font-weight:600;color:var(--text-primary)}
.section-badge{font-size:12px;color:var(--text-secondary)}

/* =============================================================
   File List
   ============================================================= */
.file-list{display:flex;flex-direction:column;gap:6px}
.file-item{
  display:flex;align-items:center;gap:10px;
  padding:10px 12px;
  background:var(--bg-page);
  border-radius:var(--radius-sm);
  transition:var(--transition);
  animation:file-in 0.3s ease-out;
}
.file-item:hover{background:var(--bg-hover)}
@keyframes file-in{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}
.file-icon{font-size:20px;flex-shrink:0}
.file-info{flex:1;min-width:0}
.file-name{font-size:14px;font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.file-meta{font-size:12px;color:var(--text-secondary);margin-top:1px}
.file-action{flex-shrink:0}

.btn-file-remove{
  width:26px;height:26px;border-radius:7px;border:none;
  background:transparent;color:var(--text-muted);
  cursor:pointer;font-size:14px;display:flex;align-items:center;justify-content:center;
  transition:var(--transition);
}
.btn-file-remove:hover{background:var(--error);color:#fff}

/* =============================================================
   Transfer Items
   ============================================================= */
.transfer-items{display:flex;flex-direction:column;gap:10px}
.transfer-item{
  padding:12px 14px;
  background:var(--bg-page);
  border-radius:var(--radius-sm);
}
.transfer-header{display:flex;justify-content:space-between;margin-bottom:5px}
.transfer-name{font-size:14px;font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.transfer-status{font-size:12px;font-weight:600;color:var(--text-secondary)}
.transfer-status.done{color:var(--success)}
.transfer-progress{
  height:3px;border-radius:2px;
  background:#e5e5e7;
  overflow:hidden;margin-bottom:5px;
}
.transfer-progress-bar{
  height:100%;border-radius:2px;
  background:var(--accent-gradient);
  transition:width 0.3s ease;
  width:0%;
}
.transfer-footer{display:flex;justify-content:space-between;font-size:11px;color:var(--text-muted)}

/* ---- Download Button ---- */
.btn-download{
  padding:4px 10px;font-size:11px;font-weight:600;
  background:var(--accent);
  color:#fff;border:none;border-radius:6px;
  cursor:pointer;font-family:var(--font);
  transition:var(--transition);
}
.btn-download:hover{background:var(--accent-hover)}

/* =============================================================
   Toast — 顶部横幅风格
   ============================================================= */
.toast-wrap{
  position:fixed;top:0;left:0;right:0;
  z-index:9999;
  display:flex;flex-direction:column;align-items:center;
  padding:12px 16px 0;
  gap:6px;
  pointer-events:none;
}
.toast{
  max-width:480px;width:100%;
  padding:12px 16px;
  background:rgba(28,28,30,0.92);
  backdrop-filter:blur(16px);
  -webkit-backdrop-filter:blur(16px);
  border-radius:var(--radius-sm);
  font-size:14px;
  color:#fff;
  box-shadow:0 8px 24px rgba(0,0,0,0.2);
  animation:toast-in 0.3s ease-out;
  pointer-events:auto;
  display:flex;align-items:center;gap:8px;
  transform-origin:top center;
}
.toast.leaving{animation:toast-out 0.25s ease-in forwards}
.toast-error{background:rgba(255,59,48,0.95)}
.toast-success{background:rgba(52,199,89,0.95)}
.toast-info{background:rgba(10,132,255,0.95)}
@keyframes toast-in{from{opacity:0;transform:translateY(-12px) scale(0.96)}to{opacity:1;transform:translateY(0) scale(1)}}
@keyframes toast-out{from{opacity:1}to{opacity:0;transform:translateY(-8px)}}

/* =============================================================
   Footer
   ============================================================= */
.footer{
  margin-top:auto;
  text-align:center;
  padding:24px 0 8px;
  font-size:12px;
  color:var(--text-muted);
}

/* =============================================================
   Utilities
   ============================================================= */
.hidden{display:none!important}

/* =============================================================
   Responsive
   ============================================================= */
@media(min-width:480px){
  .connection-grid{flex-direction:row;gap:12px}
  .conn-option{flex:1}
  .conn-divider{flex-direction:column;gap:8px;padding:8px 0}
  .conn-divider::before,.conn-divider::after{width:1px;height:auto;flex:1;min-height:20px}
}
@media(min-width:640px){
  #app{padding:0 24px 48px}
  .header{margin:0 -24px 16px;padding:18px 28px 12px}
}