/* ================================================================
   YouTube MP3 Hub — Modern Minimalist Stylesheet
   ================================================================ */
:root {
  --bg: #f8f9fc;
  --surface: #ffffff;
  --text: #1a1a2e;
  --text-secondary: #6b7280;
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --accent: #ec4899;
  --accent-soft: #fdf2f8;
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  --border: #e5e7eb;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 4px 24px rgba(0,0,0,0.06);
  --shadow-lg: 0 12px 48px rgba(0,0,0,0.08);
  --transition: 0.25s cubic-bezier(0.4,0,0.2,1);
  --max-w: 960px;
}

/* ── reset & base ────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--primary-dark); }

/* ── header ──────────────────────────────────────────────────── */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
  position: sticky; top: 0; z-index: 100;
  backdrop-filter: blur(12px);
  background: rgba(255,255,255,0.92);
}
.header-inner {
  max-width: var(--max-w); margin: 0 auto;
  padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between;
}
.logo {
  font-size: 1.4rem; font-weight: 800;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  letter-spacing: -0.5px;
}
.logo span { font-weight: 500; }
.nav-links { display: flex; gap: 28px; list-style: none; }
.nav-links a { font-size: 0.9rem; font-weight: 500; color: var(--text-secondary); }
.nav-links a:hover { color: var(--primary); }

/* ── hero ────────────────────────────────────────────────────── */
.hero {
  text-align: center; padding: 80px 24px 48px;
  max-width: var(--max-w); margin: 0 auto;
}
.hero-badge {
  display: inline-block;
  background: linear-gradient(135deg, rgba(99,102,241,0.1), rgba(236,72,153,0.1));
  color: var(--primary-dark);
  font-size: 0.85rem; font-weight: 600; padding: 6px 18px;
  border-radius: 50px; margin-bottom: 24px;
  border: 1px solid rgba(99,102,241,0.15);
}
.hero h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800; line-height: 1.15;
  letter-spacing: -1px; margin-bottom: 16px;
}
.hero h1 .gradient {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.hero .subtitle {
  font-size: 1.15rem; color: var(--text-secondary);
  max-width: 540px; margin: 0 auto 36px;
}

/* ── converter card ──────────────────────────────────────────── */
.converter {
  max-width: 680px; margin: 0 auto 80px; padding: 0 24px;
}
.converter-card {
  background: var(--surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  padding: 36px 32px;
  border: 1px solid var(--border);
  transition: box-shadow var(--transition);
}
.converter-card:focus-within { box-shadow: var(--shadow-lg), 0 0 0 4px rgba(99,102,241,0.12); }

.input-group {
  display: flex; gap: 12px; margin-bottom: 20px;
}
.input-wrapper {
  flex: 1; position: relative;
}
.input-wrapper .icon {
  position: absolute; left: 16px; top: 50%; transform: translateY(-50%);
  font-size: 1.2rem; color: var(--primary); pointer-events: none;
}
.url-input {
  width: 100%; padding: 16px 16px 16px 48px;
  font-size: 1rem; border: 2px solid var(--border);
  border-radius: var(--radius-sm); outline: none;
  background: var(--bg); color: var(--text);
  transition: border-color var(--transition);
}
.url-input:focus { border-color: var(--primary); }
.url-input::placeholder { color: #b0b7c3; }

.paste-btn {
  padding: 16px 20px; font-size: 0.9rem; font-weight: 600;
  border: 2px solid var(--border); border-radius: var(--radius-sm);
  background: var(--surface); color: var(--text-secondary);
  cursor: pointer; white-space: nowrap;
  transition: all var(--transition);
}
.paste-btn:hover { border-color: var(--primary); color: var(--primary); }

/* quality selector */
.quality-row {
  display: flex; align-items: center; gap: 12px; margin-bottom: 24px;
  flex-wrap: wrap;
}
.quality-label { font-size: 0.85rem; font-weight: 600; color: var(--text-secondary); }
.quality-options { display: flex; gap: 8px; }
.quality-btn {
  padding: 8px 18px; font-size: 0.85rem; font-weight: 600;
  border: 2px solid var(--border); border-radius: 50px;
  background: var(--surface); color: var(--text-secondary);
  cursor: pointer; transition: all var(--transition);
}
.quality-btn:hover { border-color: var(--primary); color: var(--primary); }
.quality-btn.active {
  background: var(--primary); color: #fff; border-color: var(--primary);
}

/* download button */
.convert-btn {
  width: 100%; padding: 18px; font-size: 1.1rem; font-weight: 700;
  border: none; border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--primary), #7c3aed);
  color: #fff; cursor: pointer;
  transition: all var(--transition);
  display: flex; align-items: center; justify-content: center; gap: 10px;
  box-shadow: 0 4px 20px rgba(99,102,241,0.3);
}
.convert-btn:hover { transform: translateY(-1px); box-shadow: 0 8px 28px rgba(99,102,241,0.4); }
.convert-btn:active { transform: translateY(0); }
.convert-btn:disabled { opacity: 0.6; cursor: not-allowed; transform: none; box-shadow: none; }

/* ── preview card ────────────────────────────────────────────── */
.preview {
  margin-top: 24px; padding: 20px;
  background: var(--bg); border-radius: var(--radius-sm);
  display: none; gap: 16px; align-items: center;
  border: 1px solid var(--border);
}
.preview.show { display: flex; }
.preview-thumb {
  width: 120px; height: 68px; border-radius: 8px;
  object-fit: cover; flex-shrink: 0; background: #e5e7eb;
}
.preview-info { flex: 1; min-width: 0; }
.preview-title {
  font-weight: 700; font-size: 0.95rem;
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.preview-meta {
  font-size: 0.82rem; color: var(--text-secondary);
  margin-top: 4px; display: flex; gap: 16px;
}

/* ── progress ────────────────────────────────────────────────── */
.progress-wrap { display: none; margin-top: 24px; }
.progress-wrap.show { display: block; }
.progress-bar-bg {
  height: 8px; background: var(--border);
  border-radius: 10px; overflow: hidden;
}
.progress-bar-fill {
  height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 10px; transition: width 0.5s ease;
}
.progress-text {
  text-align: center; margin-top: 10px;
  font-size: 0.85rem; color: var(--text-secondary); font-weight: 500;
}

/* ── result ──────────────────────────────────────────────────── */
.result { display: none; margin-top: 24px; }
.result.show { display: block; }
.result-card {
  background: linear-gradient(135deg, rgba(16,185,129,0.08), rgba(99,102,241,0.06));
  border: 1px solid rgba(16,185,129,0.3);
  border-radius: var(--radius-sm); padding: 24px;
  text-align: center;
}
.result-icon { font-size: 2.8rem; margin-bottom: 8px; }
.result-title { font-weight: 700; font-size: 1rem; margin-bottom: 16px;
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.download-link {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 36px; font-size: 1rem; font-weight: 700;
  background: var(--success); color: #fff;
  border-radius: 50px; transition: all var(--transition);
  box-shadow: 0 4px 16px rgba(16,185,129,0.3);
}
.download-link:hover { background: #059669; color: #fff; transform: translateY(-1px); }
.file-size { font-size: 0.82rem; color: var(--text-secondary); margin-top: 8px; }

/* error */
.error-msg {
  display: none; margin-top: 20px;
  padding: 14px 20px; background: #fef2f2;
  border: 1px solid #fecaca; border-radius: var(--radius-sm);
  color: var(--error); font-size: 0.9rem; font-weight: 500;
}
.error-msg.show { display: block; }

/* ── how it works ────────────────────────────────────────────── */
.section { max-width: var(--max-w); margin: 0 auto; padding: 64px 24px; }
.section-title {
  text-align: center; font-size: 2rem; font-weight: 800;
  margin-bottom: 12px; letter-spacing: -0.5px;
}
.section-sub {
  text-align: center; color: var(--text-secondary);
  margin-bottom: 48px; font-size: 1.05rem;
}
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.step-card {
  background: var(--surface); padding: 36px 28px;
  border-radius: var(--radius); border: 1px solid var(--border);
  text-align: center; transition: all var(--transition);
  position: relative;
}
.step-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.step-number {
  width: 48px; height: 48px; margin: 0 auto 20px;
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  font-size: 1.2rem; font-weight: 800; color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--accent));
}
.step-card h3 { font-size: 1.1rem; margin-bottom: 8px; }
.step-card p { color: var(--text-secondary); font-size: 0.92rem; }

/* ── features ────────────────────────────────────────────────── */
.features { background: var(--surface); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.feature-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.feature-item {
  display: flex; gap: 16px; padding: 24px;
  border-radius: var(--radius-sm); transition: background var(--transition);
}
.feature-item:hover { background: var(--bg); }
.feature-icon {
  width: 44px; height: 44px; flex-shrink: 0;
  border-radius: 12px; display: flex; align-items: center; justify-content: center;
  font-size: 1.3rem; background: var(--accent-soft);
}
.feature-text h4 { font-size: 1rem; margin-bottom: 4px; }
.feature-text p { color: var(--text-secondary); font-size: 0.88rem; }

/* ── faq ─────────────────────────────────────────────────────── */
.faq-list { max-width: 720px; margin: 0 auto; }
.faq-item {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-sm); margin-bottom: 12px;
  overflow: hidden; transition: all var(--transition);
}
.faq-q {
  padding: 20px 24px; font-weight: 700; font-size: 0.95rem;
  cursor: pointer; display: flex; justify-content: space-between; align-items: center;
  user-select: none;
}
.faq-q::after {
  content: '+'; font-size: 1.3rem; font-weight: 400;
  color: var(--primary); transition: transform var(--transition);
}
.faq-item.open .faq-q::after { content: '−'; }
.faq-a {
  max-height: 0; overflow: hidden; transition: max-height 0.3s ease, padding 0.3s ease;
  padding: 0 24px; font-size: 0.9rem; color: var(--text-secondary); line-height: 1.7;
}
.faq-item.open .faq-a { max-height: 400px; padding: 0 24px 20px; }

/* ── cta ─────────────────────────────────────────────────────── */
.cta {
  text-align: center; padding: 80px 24px;
  background: linear-gradient(135deg, rgba(99,102,241,0.04), rgba(236,72,153,0.04));
}
.cta h2 { font-size: 1.8rem; font-weight: 800; margin-bottom: 12px; }
.cta p { color: var(--text-secondary); margin-bottom: 28px; font-size: 1.05rem; }

/* ── footer ──────────────────────────────────────────────────── */
.site-footer {
  background: var(--text); color: rgba(255,255,255,0.7);
  padding: 48px 24px 32px; font-size: 0.88rem;
}
.footer-inner {
  max-width: var(--max-w); margin: 0 auto;
  display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px;
}
.footer-col h4 {
  color: #fff; font-size: 0.95rem; margin-bottom: 16px; font-weight: 700;
}
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 8px; }
.footer-col ul li a { color: rgba(255,255,255,0.6); }
.footer-col ul li a:hover { color: var(--accent); }
.footer-bottom {
  max-width: var(--max-w); margin: 32px auto 0; padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.1);
  text-align: center; font-size: 0.82rem; color: rgba(255,255,255,0.4);
}

/* ── responsive ──────────────────────────────────────────────── */
@media (max-width: 768px) {
  .steps { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; }
  .input-group { flex-direction: column; }
  .paste-btn { width: 100%; }
  .preview { flex-direction: column; text-align: center; }
  .nav-links { display: none; }
  .hero { padding-top: 48px; }
}

/* spinner */
@keyframes spin { to { transform: rotate(360deg); } }
.spinner {
  display: inline-block; width: 20px; height: 20px;
  border: 3px solid rgba(255,255,255,0.3);
  border-top-color: #fff; border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

/* cookie inline */
.cookie-inline {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  margin-top: 14px; padding: 10px 16px;
  background: rgba(245,158,11,0.06); border: 1px solid rgba(245,158,11,0.2);
  border-radius: var(--radius-sm); font-size: 0.82rem;
}
.cookie-inline.has-cookie {
  background: rgba(16,185,129,0.06); border-color: rgba(16,185,129,0.2);
}
.cookie-inline-icon { font-size: 1.1rem; }
.cookie-inline-status { color: var(--warning); font-weight: 500; flex: 1; min-width: 0; }
.cookie-inline.has-cookie .cookie-inline-status { color: var(--success); }
.cookie-inline-btn {
  padding: 6px 14px; font-size: 0.78rem; font-weight: 600;
  border: 1px dashed var(--warning);
  border-radius: 6px; color: var(--warning); cursor: pointer;
  background: transparent; white-space: nowrap; transition: all var(--transition);
}
.cookie-inline.has-cookie .cookie-inline-btn { border-color: var(--success); color: var(--success); }
.cookie-inline-btn:hover { background: rgba(245,158,11,0.1); }
.cookie-inline.has-cookie .cookie-inline-btn:hover { background: rgba(16,185,129,0.1); }
.cookie-inline-result { font-size: 0.78rem; }
.cookie-inline-result.success { color: var(--success); }
.cookie-inline-result.error { color: var(--error); }

/* cookie toast */
.cookie-toast {
  display: none; margin-top: 12px; padding: 14px 20px;
  background: #fef3c7; border: 1px solid #fcd34d;
  border-radius: var(--radius-sm); font-size: 0.85rem; color: #92400e;
  text-align: center; font-weight: 500;
}
.cookie-toast.show { display: block; }