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

:root {
  --bg: #0a0a0f;
  --surface: rgba(255,255,255,0.04);
  --surface-hover: rgba(255,255,255,0.08);
  --border: rgba(255,255,255,0.08);
  --border-hover: rgba(255,255,255,0.15);
  --text: #f0f0f5;
  --text-sec: #8888aa;
  --text-muted: #555577;
  --accent: #6c63ff;
  --accent2: #00d4aa;
  --glow: rgba(108,99,255,0.25);
  --radius: 16px;
  --radius-sm: 10px;
}

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
}

.noise {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  opacity: 0.03;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.gradient-bg {
  position: fixed; inset: 0; z-index: 0; pointer-events: none; overflow: hidden;
}
.gradient-sphere {
  position: absolute; border-radius: 50%; filter: blur(80px); opacity: 0.15;
  animation: floatSphere 20s ease-in-out infinite;
}
.s1 { width: 600px; height: 600px; background: #6c63ff; top: -200px; left: -200px; }
.s2 { width: 500px; height: 500px; background: #00d4aa; bottom: -150px; right: -150px; animation-delay: -7s; }
.s3 { width: 400px; height: 400px; background: #ff6b6b; top: 50%; left: 50%; transform: translate(-50%,-50%); animation-delay: -14s; }

@keyframes floatSphere {
  0%,100% { transform: translate(0,0) scale(1); }
  25% { transform: translate(50px,-50px) scale(1.05); }
  50% { transform: translate(-30px,30px) scale(0.95); }
  75% { transform: translate(40px,40px) scale(1.02); }
}

.container { position: relative; z-index: 1; max-width: 960px; margin: 0 auto; padding: 20px; min-height: 100vh; display: flex; flex-direction: column; }

header { text-align: center; padding: 28px 0 20px; }
.logo { display: flex; align-items: center; justify-content: center; gap: 14px; margin-bottom: 6px; }

.logo-icon-3d {
  width: 50px; height: 50px; perspective: 200px; position: relative;
  animation: logoFloat 3s ease-in-out infinite;
}
@keyframes logoFloat {
  0%,100% { transform: translateY(0); }
  50% { transform: translateY(-5px); }
}
.logo-icon-front, .logo-icon-back {
  position: absolute; inset: 0; border-radius: 14px; display: flex; align-items: center; justify-content: center;
  font-size: 22px; font-weight: 800; backface-visibility: hidden; transition: transform 0.6s;
}
.logo-icon-front {
  background: linear-gradient(135deg, #6c63ff, #8b83ff); color: #fff;
  box-shadow: 0 4px 24px var(--glow);
}
.logo-icon-3d:hover .logo-icon-front { transform: rotateY(180deg); }
.logo-icon-3d:hover .logo-icon-back { transform: rotateY(0); }
.logo-icon-back {
  background: linear-gradient(135deg, #00d4aa, #00e5c0); color: #fff;
  transform: rotateY(-180deg);
}
.logo-text { display: flex; align-items: baseline; gap: 6px; }
.logo-text h1 { font-size: 2rem; font-weight: 800; letter-spacing: -1px; background: linear-gradient(135deg, #f0f0f5, #8888aa); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.logo-sub { font-size: 1rem; font-weight: 400; color: var(--text-sec); }
.tagline { color: var(--text-sec); font-size: 0.9rem; }

.glass {
  background: var(--surface);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.input-section { margin: 20px 0; padding: 8px; }
.input-group { display: flex; gap: 10px; }
.input-group input {
  flex: 1; background: transparent; border: none; padding: 16px 20px;
  color: var(--text); font-size: 1rem; outline: none; font-family: inherit;
}
.input-group input::placeholder { color: var(--text-muted); }

.btn-primary {
  display: flex; align-items: center; gap: 8px; padding: 16px 32px;
  background: linear-gradient(135deg, #6c63ff, #5a52e0); color: #fff;
  border: none; border-radius: var(--radius-sm); font-size: 1rem; font-weight: 600;
  cursor: pointer; white-space: nowrap; font-family: inherit;
  transition: transform 0.2s, box-shadow 0.3s;
  box-shadow: 0 4px 20px var(--glow);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 30px var(--glow); }
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; transform: none; box-shadow: none; }
.btn-secondary {
  padding: 10px 24px; background: var(--surface-hover); color: var(--text);
  border: 1px solid var(--border); border-radius: var(--radius-sm); font-size: 0.9rem;
  cursor: pointer; font-family: inherit; transition: background 0.3s;
}
.btn-secondary:hover { background: var(--border); }

.input-hint { margin-top: 8px; font-size: 0.83rem; color: var(--text-muted); text-align: center; }
.input-hint.error { color: #ff6b6b; }

.loading-section { display: flex; flex-direction: column; align-items: center; padding: 60px 0; gap: 24px; }

.spinner-3d { position: relative; width: 60px; height: 60px; perspective: 200px; }
.spinner-ring {
  position: absolute; inset: 0; border-radius: 50%; border: 3px solid transparent;
  border-top-color: var(--accent); animation: spin3d 1s cubic-bezier(0.4,0,0.2,1) infinite;
}
.r2 { inset: 6px; border-top-color: var(--accent2); animation-delay: -0.3s; animation-direction: reverse; }
.r3 { inset: 12px; border-top-color: #ff6b6b; animation-delay: -0.6s; }
@keyframes spin3d { to { transform: rotateZ(360deg) rotateX(10deg); } }

.loading-section p { color: var(--text-sec); font-size: 0.95rem; }

.error-section { margin: 16px 0; }
.error-box { display: flex; align-items: flex-start; gap: 12px; padding: 16px 20px; }
.error-icon { font-size: 1.3rem; flex-shrink: 0; margin-top: 2px; }
.error-box p { color: #ff6b6b; font-size: 0.95rem; flex: 1; }
.retry-btn { margin-left: auto; padding: 6px 16px; background: rgba(255,107,107,0.15); color: #ff6b6b; border: 1px solid rgba(255,107,107,0.3); border-radius: var(--radius-sm); cursor: pointer; font-size: 0.85rem; transition: background 0.3s; }
.retry-btn:hover { background: rgba(255,107,107,0.25); }

.results-section { margin: 20px 0; animation: fadeUp 0.5s ease; }
@keyframes fadeUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }

.video-info { display: flex; gap: 20px; padding: 16px; margin-bottom: 28px; transition: border-color 0.3s; }
.video-info:hover { border-color: var(--border-hover); }

.video-thumbnail { position: relative; flex-shrink: 0; width: 260px; border-radius: var(--radius-sm); overflow: hidden; }
.thumb-wrapper { position: relative; overflow: hidden; border-radius: var(--radius-sm); }
.thumb-wrapper img { width: 100%; height: auto; display: block; transition: transform 0.5s ease; }
.thumb-wrapper:hover img { transform: scale(1.05); }
.thumb-overlay {
  position: absolute; inset: 0; background: linear-gradient(to top, rgba(0,0,0,0.4), transparent);
  pointer-events: none;
}
.duration-badge {
  position: absolute; bottom: 8px; right: 8px;
  background: rgba(0,0,0,0.85); color: #fff; padding: 3px 10px;
  border-radius: 6px; font-size: 0.8rem; font-weight: 600; backdrop-filter: blur(4px);
}

.video-meta { flex: 1; min-width: 0; }
.video-meta h2 { font-size: 1.2rem; font-weight: 700; line-height: 1.4; margin-bottom: 8px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.video-author { color: var(--text-sec); font-size: 0.9rem; margin-bottom: 4px; }
.video-views { color: var(--text-muted); font-size: 0.85rem; }

.format-section { margin-top: 24px; animation: fadeUp 0.5s ease; }
.section-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.section-title { font-size: 1.15rem; font-weight: 700; display: flex; align-items: center; gap: 8px; }
.section-icon { font-size: 1.2rem; }
.section-count { font-size: 0.83rem; color: var(--text-sec); background: var(--surface); padding: 4px 12px; border-radius: 20px; border: 1px solid var(--border); }

.formats-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 12px; }
.audio-grid { grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); }

.format-card {
  position: relative; display: flex; align-items: center; gap: 14px;
  padding: 16px 18px; border-radius: var(--radius); cursor: pointer;
  background: var(--surface); border: 1px solid var(--border);
  animation: cardIn 0.4s ease backwards;
  animation-delay: var(--card-delay, 0s);
  overflow: hidden;
  transition: transform 0.25s cubic-bezier(0.34,1.56,0.64,1), border-color 0.3s, box-shadow 0.3s;
}
@keyframes cardIn { from { opacity: 0; transform: translateY(20px) scale(0.95); } to { opacity: 1; transform: translateY(0) scale(1); } }
.format-card:hover {
  transform: translateY(-3px) scale(1.01);
  border-color: var(--border-hover);
  box-shadow: 0 8px 40px rgba(108,99,255,0.12);
}
.format-card:active { transform: translateY(-1px) scale(0.99); }

.card-glow {
  position: absolute; top: -50%; left: -50%; width: 200%; height: 200%;
  background: radial-gradient(circle at 50% 50%, var(--card-color, #6c63ff), transparent 60%);
  opacity: 0; transition: opacity 0.4s; pointer-events: none;
}
.format-card:hover .card-glow { opacity: 0.06; }

.card-badge {
  flex-shrink: 0; width: 44px; height: 44px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.7rem; font-weight: 800; color: #fff; letter-spacing: 0.5px;
  position: relative; z-index: 1;
  box-shadow: 0 2px 12px rgba(0,0,0,0.2);
}
.audio-badge { background: linear-gradient(135deg, #00d4aa, #00b894) !important; }

.card-icon { font-size: 1.1rem; flex-shrink: 0; }

.card-info { flex: 1; min-width: 0; }
.card-title { font-size: 0.95rem; font-weight: 600; line-height: 1.3; }
.card-meta { display: flex; gap: 10px; margin-top: 3px; font-size: 0.78rem; color: var(--text-sec); }
.card-meta span { display: flex; align-items: center; gap: 3px; }

.card-action { flex-shrink: 0; }
.download-btn {
  display: inline-block; padding: 6px 14px; border-radius: 8px;
  font-size: 0.78rem; font-weight: 600; color: var(--accent);
  background: rgba(108,99,255,0.1); border: 1px solid rgba(108,99,255,0.2);
  transition: background 0.3s, color 0.3s;
}
.format-card:hover .download-btn {
  background: var(--accent); color: #fff; border-color: var(--accent);
}

.download-section {
  position: fixed; inset: 0; background: rgba(0,0,0,0.6);
  backdrop-filter: blur(8px); display: flex; align-items: center; justify-content: center;
  z-index: 1000; padding: 20px;
  animation: fadeIn 0.3s ease;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.download-modal { padding: 28px; width: 100%; max-width: 480px; animation: modalIn 0.3s ease; }
@keyframes modalIn { from { opacity: 0; transform: scale(0.9) translateY(20px); } to { opacity: 1; transform: scale(1) translateY(0); } }

.download-header { display: flex; align-items: center; gap: 16px; margin-bottom: 24px; }
.download-icon-3d {
  width: 54px; height: 54px; border-radius: 14px;
  background: linear-gradient(135deg, rgba(108,99,255,0.2), rgba(0,212,170,0.2));
  display: flex; align-items: center; justify-content: center; font-size: 1.5rem;
  animation: bounce 2s ease-in-out infinite;
}
@keyframes bounce {
  0%,100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}
.download-info { flex: 1; min-width: 0; }
.download-filename { font-weight: 700; font-size: 1rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.download-format { color: var(--text-sec); font-size: 0.85rem; margin-top: 2px; }

.progress-container { margin-bottom: 20px; }
.progress-bar { width: 100%; height: 8px; background: rgba(255,255,255,0.06); border-radius: 4px; overflow: hidden; margin-bottom: 12px; }
.progress-fill { height: 100%; width: 0%; background: linear-gradient(90deg, var(--accent), #8b83ff, var(--accent)); background-size: 200% 100%; border-radius: 4px; transition: width 0.3s ease; animation: shimmer 2s linear infinite; }
@keyframes shimmer { 0% { background-position: 200% 0; } 100% { background-position: -200% 0; } }
.progress-details { display: flex; justify-content: space-between; font-size: 0.83rem; color: var(--text-sec); }
.progress-percent { font-weight: 700; color: var(--text); }

.download-status { text-align: center; margin-bottom: 16px; }
.status-text { color: var(--text-sec); font-size: 0.9rem; }
.status-text.success { color: var(--accent2); }
.status-text.error { color: #ff6b6b; }

.toast-container { position: fixed; top: 20px; right: 20px; z-index: 9999; display: flex; flex-direction: column; gap: 8px; }
.toast {
  display: flex; align-items: center; gap: 10px;
  padding: 14px 22px; border-radius: var(--radius-sm); color: #fff;
  font-size: 0.88rem; font-weight: 500; box-shadow: 0 8px 32px rgba(0,0,0,0.4);
  backdrop-filter: blur(10px); border: 1px solid rgba(255,255,255,0.1);
  transform: translateX(120%); transition: transform 0.3s cubic-bezier(0.34,1.56,0.64,1);
  max-width: 380px;
}
.toast.show { transform: translateX(0); }
.toast.success { background: rgba(0,212,170,0.2); border-color: rgba(0,212,170,0.3); }
.toast.error { background: rgba(255,107,107,0.2); border-color: rgba(255,107,107,0.3); }
.toast.info { background: rgba(108,99,255,0.2); border-color: rgba(108,99,255,0.3); }
.toast-icon { font-size: 1.1rem; }

footer { margin-top: auto; padding: 40px 0 16px; text-align: center; }
footer p { color: var(--text-muted); font-size: 0.83rem; }
.footer-note { font-size: 0.73rem; margin-top: 4px; opacity: 0.6; }

.hidden { display: none !important; }

.spinner-sm {
  display: inline-block; width: 18px; height: 18px;
  border: 2px solid rgba(255,255,255,0.3); border-top-color: #fff;
  border-radius: 50%; animation: spin 0.6s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

@media (max-width: 768px) {
  .container { padding: 12px; }
  .input-group { flex-direction: column; }
  .btn-primary { justify-content: center; }
  .video-info { flex-direction: column; }
  .video-thumbnail { width: 100%; }
  .formats-grid { grid-template-columns: 1fr; }
  .audio-grid { grid-template-columns: 1fr; }
  .format-card { padding: 14px 16px; }
  .download-modal { padding: 20px; }
  .progress-details { flex-wrap: wrap; gap: 4px; }
  header { padding: 20px 0 16px; }
  .logo-text h1 { font-size: 1.6rem; }
}

@media (max-width: 480px) {
  .formats-grid { grid-template-columns: 1fr; }
  .format-card { gap: 10px; }
  .card-badge { width: 36px; height: 36px; font-size: 0.6rem; }
  .download-modal { padding: 16px; }
  .toast { max-width: calc(100vw - 24px); }
}

@media (min-width: 1200px) {
  .formats-grid { grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); }
  .container { max-width: 1100px; }
}

.direct-download-section {
  margin-top: 16px;
  padding: 16px;
  background: rgba(255, 107, 107, 0.1);
  border: 1px solid rgba(255, 107, 107, 0.3);
  border-radius: var(--radius-sm);
  text-align: center;
}
.direct-download-notice {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-sec);
  margin-bottom: 12px;
  text-align: left;
}
.notice-icon { font-size: 1.1rem; flex-shrink: 0; }
.direct-download-btn {
  display: inline-block;
  padding: 12px 24px;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9rem;
  transition: all 0.2s;
}
.direct-download-btn:hover {
  background: #7b73ff;
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(108, 99, 255, 0.4);
}
.direct-download-hint {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 8px;
}
.status-text.warning { color: #ffa726; }
.status-text.error { color: #ff6b6b; }
.status-text.success { color: #66bb6a; }