/* ============================================
   Wormhole Lite — 金色虫洞主题
   暖金琥珀 · 半透明交互 · 深空背景
   ============================================ */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  /* —— 金色深渊调色板 —— */
  --bg:             #050302;
  --bg-card:        rgba(18, 12, 8, 0.55);
  --border:         rgba(180, 130, 90, 0.12);
  --border-glow:    rgba(200, 140, 80, 0.25);
  --text:           #f5efe6;
  --text-secondary: #b8a89a;
  --text-muted:     #7a6b5e;

  /* —— 暖金主色 —— */
  --primary:        #c89050;
  --primary-hover:  #a07038;
  --primary-glow:   rgba(200, 140, 80, 0.18);
  --primary-ghost:  rgba(180, 120, 70, 0.07);

  /* —— 琥珀橙点缀 —— */
  --accent:         #e07840;
  --accent-glow:    rgba(224, 120, 64, 0.18);

  /* —— 状态色 —— */
  --success:        #5cb878;
  --success-bg:     rgba(92, 184, 120, 0.10);
  --danger:         #e05555;
  --danger-bg:      rgba(30, 8, 8, 0.55);

  /* —— 形状 —— */
  --radius-sm:      8px;
  --radius:         16px;
  --radius-lg:      22px;

  /* —— 阴影 —— */
  --shadow-sm:      0 2px 8px rgba(0,0,0,0.4);
  --shadow:         0 4px 28px rgba(0,0,0,0.5), 0 1px 4px rgba(0,0,0,0.3);
  --shadow-lg:      0 12px 50px rgba(0,0,0,0.55), 0 2px 8px rgba(0,0,0,0.3);
  --shadow-glow:    0 0 60px rgba(200,140,80,0.15), 0 0 100px rgba(180,100,55,0.06);

  /* —— 过渡 —— */
  --ease-out:       cubic-bezier(0.16, 1, 0.3, 1);
  --ease-spring:    cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ============================================
   基础 & 金色虫洞背景
   ============================================ */

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  position: relative;
  overflow-x: hidden;

  /* 底色与背景图颜色匹配 — 图片加载前不闪白 */
  background-color: #543a33;

  /* 背景图 + 星光 + 渐变遮罩 */
  background-image:
    /* 微星光 */
    radial-gradient(1px 1px at 20% 18%, rgba(220,180,140,0.4), transparent),
    radial-gradient(1px 1px at 50% 8%,  rgba(255,200,140,0.3), transparent),
    radial-gradient(1.5px 1.5px at 78% 22%, rgba(255,180,100,0.35), transparent),
    radial-gradient(1px 1px at 88% 50%, rgba(220,180,140,0.2), transparent),
    radial-gradient(1.5px 1.5px at 12% 58%, rgba(255,180,100,0.3), transparent),
    radial-gradient(1px 1px at 35% 72%, rgba(220,180,140,0.2), transparent),
    radial-gradient(1px 1px at 65% 80%, rgba(255,200,140,0.2), transparent),
    radial-gradient(1.5px 1.5px at 92% 75%, rgba(255,180,100,0.25), transparent),
    radial-gradient(1px 1px at 25% 40%, rgba(220,180,140,0.18), transparent),
    radial-gradient(1px 1px at 58% 32%, rgba(255,200,140,0.22), transparent),
    /* 渐变遮罩 — 上浅下深 */
    linear-gradient(180deg, rgba(5,3,2,0.0) 0%, rgba(5,3,2,0.08) 45%, rgba(5,3,2,0.20) 100%),
    /* ★ 背景图（WebP 仅 151 KB，瞬间加载） ★ */
    url('/wormhole/bg-wormhole.webp');
  background-size: cover;
  background-position: center top;
  background-attachment: fixed;
}

/* —— 暖金光球装饰 —— */
body::before,
body::after {
  content: '';
  position: fixed;
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}

body::before {
  width: 480px;
  height: 480px;
  background: radial-gradient(circle, rgba(200,140,80,0.09) 0%, rgba(200,140,80,0.015) 40%, transparent 70%);
  top: -140px;
  left: -60px;
  filter: blur(90px);
  animation: orbFloat1 12s ease-in-out infinite;
}

body::after {
  width: 360px;
  height: 360px;
  background: radial-gradient(circle, rgba(180,100,55,0.06) 0%, rgba(180,100,55,0.01) 40%, transparent 70%);
  bottom: -80px;
  right: -40px;
  filter: blur(75px);
  animation: orbFloat2 15s ease-in-out infinite;
}

@keyframes orbFloat1 {
  0%, 100% { transform: translate(0,0) scale(1);    opacity: 0.45; }
  25%      { transform: translate(40px,15px) scale(1.1); opacity: 0.55; }
  50%      { transform: translate(10px,40px) scale(0.9);  opacity: 0.35; }
  75%      { transform: translate(-20px,10px) scale(1.05); opacity: 0.5; }
}

@keyframes orbFloat2 {
  0%, 100% { transform: translate(0,0) scale(1);     opacity: 0.3; }
  33%      { transform: translate(-30px,-15px) scale(1.12); opacity: 0.4; }
  66%      { transform: translate(-5px,-30px) scale(0.85);  opacity: 0.22; }
}

/* ============================================
   头部
   ============================================ */

.header {
  text-align: center;
  padding: 8px 20px 8px;
  position: relative;
  z-index: 1;
}

.logo {
  font-size: 34px;
  font-weight: 800;
  letter-spacing: -1px;
  background: linear-gradient(135deg, #c89860 0%, #e0b870 30%, #c08050 60%, #c89050 100%);
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: logoShine 5s linear infinite;
  position: relative;
}

/* Logo 金色光晕 — 用伪元素避免 filter 与 background-clip 冲突 */
.header::before {
  content: '';
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 280px; height: 50px;
  background: radial-gradient(ellipse, rgba(200,140,80,0.18) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  z-index: -1;
  animation: headerGlow 3s ease-in-out infinite;
}

@keyframes headerGlow {
  0%, 100% { opacity: 0.5; transform: translate(-50%, -50%) scale(1); }
  50%      { opacity: 1;   transform: translate(-50%, -50%) scale(1.15); }
}

@keyframes logoShine {
  to { background-position: 200% center; }
}

.logo span {
  font-weight: 500;
  background: linear-gradient(135deg, var(--text) 0%, var(--text-secondary) 100%);
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  margin-top: 10px;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 400;
  letter-spacing: 0.4px;
}

/* ============================================
   主容器
   ============================================ */

.container {
  width: 100%;
  max-width: 560px;
  padding: 0 20px;
  position: relative;
  z-index: 1;
}

/* ============================================
   拖拽上传区 — 半透明交互卡片
   ============================================ */

.drop-zone {
  background: var(--bg-card);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  cursor: pointer;
  transition: all 0.4s var(--ease-out);
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
}

.drop-zone::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 300px 200px at 50% 60%, rgba(200,140,80,0.05) 0%, transparent 70%),
    radial-gradient(ellipse 150px 100px at 50% 55%, rgba(180,100,55,0.03) 0%, transparent 60%);
  opacity: 0.6;
  transition: opacity 0.5s var(--ease-out);
  pointer-events: none;
}

.drop-zone::after {
  content: '';
  position: absolute;
  inset: -2px;
  border-radius: var(--radius-lg);
  padding: 2px;
  background: conic-gradient(
    from 0deg,
    transparent, transparent,
    rgba(200,140,80,0.14), transparent,
    rgba(180,100,55,0.08), transparent,
    transparent
  );
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity 0.5s var(--ease-out);
  pointer-events: none;
}

.drop-zone:hover::before,
.drop-zone.drag-over::before { opacity: 1; }
.drop-zone:hover::after,
.drop-zone.drag-over::after { opacity: 1; }

.drop-zone:hover,
.drop-zone.drag-over {
  border-color: var(--border-glow);
  box-shadow: var(--shadow-glow), var(--shadow-lg);
  transform: translateY(-3px);
}

.drop-zone.drag-over {
  border-style: solid;
  background: rgba(40, 22, 10, 0.55);
}

.drop-zone-icon {
  font-size: 48px;
  margin-bottom: 14px;
  position: relative;
  z-index: 1;
  transition: transform 0.4s var(--ease-spring);
  filter: drop-shadow(0 0 20px rgba(200,140,80,0.3));
}

.drop-zone:hover .drop-zone-icon,
.drop-zone.drag-over .drop-zone-icon {
  transform: scale(1.15);
  filter: drop-shadow(0 0 35px rgba(200,140,80,0.45));
}

.drop-zone-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 6px;
  position: relative;
  z-index: 1;
  color: var(--text);
}

.drop-zone-hint {
  font-size: 13px;
  color: var(--text-secondary);
  position: relative;
  z-index: 1;
}

.file-input { display: none; }

/* ============================================
   文件信息卡片
   ============================================ */

.file-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 22px 24px;
  margin-top: 16px;
  box-shadow: var(--shadow);
  display: none;
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border);
  transition: box-shadow 0.3s var(--ease-out);
  position: relative;
  overflow: hidden;
}

.file-card::before {
  content: '';
  position: absolute;
  top: 0; left: 20px; right: 20px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(200,140,80,0.25), transparent);
  pointer-events: none;
}

.file-card.visible { display: block; }

.file-card-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 14px;
}

.file-icon {
  width: 46px;
  height: 46px;
  background: rgba(200,140,80,0.08);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  flex-shrink: 0;
  border: 1px solid rgba(200,140,80,0.14);
}

.file-name {
  font-weight: 600;
  font-size: 14px;
  word-break: break-all;
  color: var(--text);
}

.file-size {
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 2px;
}

/* ============================================
   进度条 — 金色流光
   ============================================ */

.progress-bar {
  height: 6px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 3px;
  overflow: hidden;
  position: relative;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #c89050, #b07040, #c89860);
  background-size: 200% 100%;
  border-radius: 3px;
  width: 0%;
  transition: width 0.5s var(--ease-out);
  position: relative;
  animation: progressFlow 2s linear infinite;
}

@keyframes progressFlow {
  to { background-position: 200% 0; }
}

.progress-fill::after {
  content: '';
  position: absolute;
  right: 0; top: 0; bottom: 0;
  width: 30px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2));
  border-radius: 0 3px 3px 0;
}

.progress-text {
  text-align: center;
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 8px;
  font-weight: 500;
}

/* ============================================
   设置面板
   ============================================ */

.settings-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 20px 24px;
  margin-top: 14px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

.settings-card::before {
  content: '';
  position: absolute;
  top: 0; left: 20px; right: 20px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(200,140,80,0.18), transparent);
  pointer-events: none;
}

.settings-row {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.settings-row + .settings-row {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid rgba(200,140,80,0.07);
}

.settings-label {
  font-size: 12px;
  font-weight: 700;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.8px;
}

.settings-options {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

/* Chip */
.chip {
  padding: 7px 16px;
  border-radius: 20px;
  border: 1.5px solid var(--border);
  background: transparent;
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.25s var(--ease-out);
  font-family: inherit;
  color: var(--text-secondary);
  position: relative;
  overflow: hidden;
}

.chip::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(200,140,80,0.07), rgba(180,100,55,0.04));
  opacity: 0;
  transition: opacity 0.25s var(--ease-out);
  border-radius: inherit;
}

.chip:hover::before { opacity: 1; }

.chip:hover {
  border-color: var(--border-glow);
  color: var(--text);
  transform: translateY(-1px);
}

.chip.active {
  background: linear-gradient(135deg, #a07038, #c89050);
  border-color: transparent;
  color: #1a1006;
  box-shadow: 0 2px 16px rgba(200,140,80,0.28);
  font-weight: 700;
}

.chip.active::before { opacity: 0; }

.custom-input-wrap {
  display: flex;
  align-items: center;
  gap: 6px;
}

.custom-input {
  width: 90px;
  padding: 7px 10px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-family: inherit;
  color: var(--text);
  background: rgba(255,255,255,0.05);
  text-align: center;
  transition: all 0.25s var(--ease-out);
  /* 隐藏默认数字箭头 */
  -moz-appearance: textfield;
}

.custom-input::-webkit-outer-spin-button,
.custom-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.custom-input:focus {
  border-color: var(--primary);
  outline: none;
  box-shadow: 0 0 0 3px var(--primary-glow);
  background: rgba(200,140,80,0.04);
}

.custom-input::placeholder { color: var(--text-muted); }

.custom-unit {
  font-size: 12px;
  color: var(--text-secondary);
  font-weight: 500;
}

/* ============================================
   按钮
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 28px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all 0.25s var(--ease-out);
  font-family: inherit;
  position: relative;
  overflow: hidden;
}

.btn::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at center, rgba(255,255,255,0.22) 0%, transparent 70%);
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}

.btn:active::after { opacity: 1; transition: opacity 0s; }

.btn-primary {
  background: linear-gradient(135deg, #a07038 0%, #c89050 50%, #b07040 100%);
  color: #1a1006;
  width: 100%;
  box-shadow: 0 4px 24px rgba(200,140,80,0.22);
  animation: btnPulse 3s ease-in-out infinite;
}

@keyframes btnPulse {
  0%, 100% { box-shadow: 0 4px 24px rgba(200,140,80,0.22); }
  50%      { box-shadow: 0 4px 35px rgba(200,140,80,0.35), 0 0 50px rgba(180,100,55,0.10); }
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 35px rgba(200,140,80,0.38), 0 0 60px rgba(180,100,55,0.12);
  animation: none;
}

.btn-primary:active { transform: translateY(0); }

.btn-primary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
  animation: none;
}

.btn-outline {
  background: transparent;
  border: 1.5px solid var(--border);
  color: var(--text);
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(200,140,80,0.06);
  transform: translateY(-1px);
}

/* ============================================
   分享结果
   ============================================ */

.share-result {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 30px 24px;
  margin-top: 16px;
  box-shadow: var(--shadow-lg);
  display: none;
  text-align: center;
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

.share-result::before {
  content: '';
  position: absolute;
  top: 0; left: 20px; right: 20px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(92,184,120,0.35), transparent);
  pointer-events: none;
}

.share-result::after {
  content: '';
  position: absolute;
  top: -50px;
  left: 50%;
  transform: translateX(-50%);
  width: 250px;
  height: 100px;
  background: radial-gradient(ellipse, rgba(92,184,120,0.08) 0%, transparent 70%);
  pointer-events: none;
}

.share-result.visible { display: block; }

.share-result-icon {
  font-size: 56px;
  margin-bottom: 10px;
  animation: popIn 0.5s var(--ease-spring);
}

.share-result-title {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--text);
}

.share-result-hint {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 16px;
  font-weight: 500;
}

.share-status {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-bottom: 14px;
  padding: 10px 16px;
  background: rgba(200,140,80,0.07);
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 500;
  color: var(--primary);
  border: 1px solid rgba(200,140,80,0.10);
}

.qr-wrap {
  margin: 0 auto 16px;
  width: 200px;
  height: 200px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: #fff;
  padding: 6px;
  box-shadow: 0 4px 20px rgba(200,140,80,0.12);
}

.qr-wrap canvas {
  width: 100%;
  height: 100%;
  image-rendering: pixelated;
  border-radius: 4px;
}

.share-link-box {
  display: flex;
  gap: 8px;
}

.share-link-input {
  flex: 1;
  padding: 11px 16px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  color: var(--text);
  background: rgba(255,255,255,0.03);
  transition: border-color 0.2s var(--ease-out);
}

.share-link-input:focus {
  border-color: var(--primary);
  outline: none;
  box-shadow: 0 0 0 3px rgba(200,140,80,0.1);
}

.btn-copy {
  padding: 11px 18px;
  background: linear-gradient(135deg, #a07038, #c89050);
  color: #1a1006;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  white-space: nowrap;
  transition: all 0.2s var(--ease-out);
  font-family: inherit;
  position: relative;
  overflow: hidden;
}

.btn-copy:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(200,140,80,0.28);
}

.btn-copy:active { transform: translateY(0); }

.btn-copy.copied {
  background: linear-gradient(135deg, #3d8b5e, #5cb878);
  color: #fff;
  box-shadow: 0 4px 20px rgba(92,184,120,0.28);
}

/* ============================================
   下载页面
   ============================================ */

.download-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 38px 28px;
  box-shadow: var(--shadow);
  text-align: center;
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

.download-card::before {
  content: '';
  position: absolute;
  top: 0; left: 20px; right: 20px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(200,140,80,0.22), transparent);
  pointer-events: none;
}

.download-card .file-name {
  font-size: 18px;
  margin: 14px 0 6px;
}

.download-card .file-size {
  font-size: 14px;
  margin-bottom: 24px;
}

/* ============================================
   错误卡片
   ============================================ */

.error-card {
  background: var(--danger-bg);
  border: 1.5px solid rgba(224,85,85,0.22);
  border-radius: var(--radius);
  padding: 38px 28px;
  text-align: center;
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
}

.error-card-icon { font-size: 56px; margin-bottom: 10px; }

.error-card-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--danger);
  margin-bottom: 6px;
}

.error-card-desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ============================================
   底部
   ============================================ */

.footer {
  padding: 24px 20px;
  text-align: center;
  font-size: 12px;
  color: var(--text-muted);
  position: relative;
  z-index: 1;
}

.footer a { color: var(--primary); text-decoration: none; transition: color 0.2s; }
.footer a:hover { color: var(--accent); }

/* ============================================
   动画
   ============================================ */

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes popIn {
  0%   { transform: scale(0.4); opacity: 0; }
  60%  { transform: scale(1.1); }
  100% { transform: scale(1); opacity: 1; }
}

.fade-in { animation: fadeIn 0.45s var(--ease-out); }

/* ============================================
   Lucide 图标尺寸
   ============================================ */

.logo [data-lucide]       { width: 1em; height: 1em; vertical-align: -0.12em; margin-right: 2px; }
.drop-zone-icon [data-lucide] { width: 48px; height: 48px; }
.settings-label [data-lucide] { width: 14px; height: 14px; vertical-align: -0.2em; margin-right: 3px; }
.file-icon [data-lucide]  { width: 22px; height: 22px; }
.share-result-icon [data-lucide] { width: 56px; height: 56px; }
.error-card-icon [data-lucide]   { width: 56px; height: 56px; }
.btn [data-lucide],
.btn-copy [data-lucide]   { width: 16px; height: 16px; }

/* 下载页 */
.loading-icon             { font-size: 44px; margin-bottom: 12px; }
.loading-icon [data-lucide]    { width: 44px; height: 44px; animation: spin 1s linear infinite; }
.download-package-icon        { font-size: 52px; margin-bottom: 8px; }
.download-package-icon [data-lucide] { width: 52px; height: 52px; }
.back-link {
  display: inline-block; margin-top: 16px;
  color: var(--primary); text-decoration: none; font-weight: 600;
  transition: color 0.2s;
}
.back-link:hover { color: var(--accent); }

@keyframes spin { to { transform: rotate(360deg); } }

/* ============================================
   Space Grotesk 字体
   ============================================ */

.logo {
  font-family: 'Space Grotesk', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-weight: 700;
}

.drop-zone-title,
.share-result-title,
.error-card-title,
.download-card .file-name {
  font-family: 'Space Grotesk', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-weight: 600;
}

.settings-label {
  font-family: 'Space Grotesk', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* ============================================
   响应式
   ============================================ */

@media (max-width: 480px) {
  .header { padding: 20px 16px 16px; }
  .logo   { font-size: 27px; }

  body::before,
  body::after { filter: blur(65px); }

  .drop-zone { padding: 28px 18px; }
  .drop-zone-icon { font-size: 40px; }
  .drop-zone-title { font-size: 16px; }
  .share-link-box { flex-direction: column; }
  .settings-row { gap: 8px; }
  .chip { padding: 6px 12px; font-size: 11px; }
  .download-card { padding: 28px 18px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}