/* style.css - Modern, High-Fidelity Professional Look */
:root {
  --primary: #0f172a;
  --accent: #06b6d4;
  --accent-gradient: linear-gradient(135deg, #06b6d4 0%, #3b82f6 100%);
  --tiktok-gradient: linear-gradient(90deg, #ff0050, #00f2ea);
  --error: #ef4444;
  --success: #10b981;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --shadow: 0 10px 25px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.02);
}

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  margin: 0;
  padding: 0;
  font-family: 'Inter', 'Noto Sans KR', sans-serif;
  background-color: var(--bg);
  color: var(--text-main);
  line-height: 1.6;
}

/* Hero Section */
.hero {
  background-color: var(--primary);
  background-image: radial-gradient(circle at 2px 2px, rgba(255,255,255,0.05) 1px, transparent 0);
  background-size: 32px 32px;
  color: #fff;
  padding: 4rem 1rem 6rem 1rem;
  text-align: center;
  position: relative;
}

.top-nav {
  position: absolute;
  top: 1.5rem;
  left: 1.5rem;
  right: auto;
  z-index: 100;
  text-align: left;
}

.lang-switcher select {
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.2);
  padding: 6px 12px;
  border-radius: 8px;
  font-size: 0.875rem;
  cursor: pointer;
  outline: none;
  backdrop-filter: blur(4px);
}
.lang-switcher select option { color: #000; }

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  margin: 0;
  letter-spacing: -0.05em;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-subtitle {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0.5rem 0 1.5rem 0;
  opacity: 0.9;
}
.brand-badges {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  font-size: 1.75rem;
  opacity: 0.85;
}
.brand-badges i {
  transition: transform 0.2s;
}
.brand-badges i:hover {
  transform: scale(1.2);
  opacity: 1;
}
.fa-tiktok { color: #fff; }
.fa-instagram { color: #E1306C; }
.fa-youtube { color: #FF0000; }
.fa-twitter { color: #1DA1F2; }

.hero-description {
  max-width: 600px;
  margin: 0 auto;
  font-size: 1.1rem;
  color: var(--text-muted);
  color: rgba(255, 255, 255, 0.6);
}

/* Main Container */
.container {
  max-width: 720px;
  margin: -3rem auto 3rem auto;
  padding: 0 1.5rem;
  position: relative;
}

/* Download Card */
.download-card {
  background: var(--card-bg);
  padding: 2rem;
  border-radius: 24px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.input-group {
  display: flex;
  gap: 0.75rem;
  margin-bottom: 0;
}

.url-input {
  flex: 1;
  padding: 1rem 1.25rem;
  border: 2px solid var(--border);
  border-radius: 12px;
  font-size: 1rem;
  transition: all 0.2s ease;
  outline: none;
}
.url-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(6, 182, 212, 0.1);
}

.download-btn {
  background: var(--accent-gradient);
  color: #fff;
  border: none;
  border-radius: 12px;
  padding: 0 1.5rem;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.1s active, opacity 0.2s;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  white-space: nowrap;
}
.download-btn:hover { opacity: 0.9; }
.download-btn:active { transform: scale(0.98); }
.download-btn:disabled { background: #94a3b8; cursor: not-allowed; }

/* Status UI */
.status-ui {
  margin-top: 2rem;
  text-align: center;
  padding: 1.5rem;
  border-radius: 16px;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.status-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.loading .spinner {
  width: 40px;
  height: 40px;
  border: 4px solid #f1f5f9;
  border-top-color: var(--accent);
  border-radius: 50%;
  margin: 0 auto 1rem auto;
  animation: spin 1s linear infinite;
}
@keyframes spin { 100% { transform: rotate(360deg); } }

/* Progress Bar */
.progress-container {
  margin: 2rem 0;
}
.progress-bar-wrapper {
  width: 100%;
  height: 14px;
  background: #f1f5f9;
  border-radius: 100px;
  overflow: hidden;
  margin-bottom: 0.75rem;
}
.progress-fill {
  width: 0%;
  height: 100%;
  background: var(--tiktok-gradient);
  border-radius: 100px;
  transition: width 0.1s linear;
}
.progress-info {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--primary);
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse 1.5s infinite;
}
@keyframes pulse {
  0% { transform: scale(0.8); opacity: 0.5; }
  50% { transform: scale(1.2); opacity: 1; }
  100% { transform: scale(0.8); opacity: 0.5; }
}

.small-notice {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.btn-secondary {
  background: #f1f5f9;
  color: var(--text-main);
  border: 1px solid var(--border);
  padding: 0.75rem 1.5rem;
  border-radius: 10px;
  font-weight: 600;
  cursor: pointer;
}

.error-msg { color: var(--error); margin-bottom: 1.5rem; }

/* How to Use (Compact Horizontal Flow) */
.how-to {
  margin-top: 4rem;
  padding: 3rem 0;
  background: linear-gradient(180deg, #fff 0%, #f8faff 100%);
  border-radius: 40px;
}

.howto-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 3rem;
  max-width: 1100px;
  margin-left: auto;
  margin-right: auto;
}

.howto-step {
  background: #fff;
  padding: 2.5rem 1.5rem;
  border-radius: 28px;
  text-align: center;
  border: 1px solid rgba(0, 0, 0, 0.04);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.03);
  transition: all 0.4s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.howto-step::before {
  content: attr(data-step);
  position: absolute;
  top: -5px;
  right: 15px;
  font-size: 5rem;
  font-weight: 900;
  color: rgba(37, 99, 235, 0.03);
  line-height: 1;
  z-index: 0;
}

.howto-step:hover {
  transform: translateY(-8px);
  border-color: var(--primary);
  box-shadow: 0 15px 35px rgba(37, 99, 235, 0.08);
}

.step-icon {
  font-size: 3rem;
  margin-bottom: 1.25rem;
  position: relative;
  z-index: 1;
}

.howto-step h4 {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 0.75rem;
  position: relative;
  z-index: 1;
}

.howto-step p {
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--text-muted);
  font-weight: 500;
  position: relative;
  z-index: 1;
  margin: 0;
}

@media (max-width: 900px) {
  .howto-grid {
    grid-template-columns: 1fr;
    max-width: 450px;
    gap: 2rem;
  }
}

/* Features */
.features {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
  margin-top: 3rem;
}
.feature-item {
  background: #fff;
  padding: 1.5rem;
  border-radius: 20px;
  text-align: center;
  border: 1px solid var(--border);
}
.feature-icon { font-size: 2rem; margin-bottom: 0.5rem; }
.feature-item h4 { margin: 0 0 0.5rem 0; font-size: 1.1rem; }
.feature-item p { margin: 0; font-size: 0.9rem; color: var(--text-muted); }

/* FAQ */
.faq { margin-top: 4rem; }
.section-title { text-align: center; margin-bottom: 2rem; }
.faq-item {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 12px;
  margin-bottom: 0.75rem;
  overflow: hidden;
}
.faq-question {
  width: 100%;
  padding: 1.25rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: none;
  border: none;
  font-size: 1rem;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
}
.faq-answer {
  display: none;
  padding: 0 1.25rem 1.25rem 1.25rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}
.faq-item.active .faq-answer { display: block; }
.faq-item.active .fa-chevron-down { transform: rotate(180deg); }

.legal-box {
  margin-top: 3rem;
  padding: 1.5rem;
  background: #fffbeb;
  border: 1px solid #fef3c7;
  border-radius: 12px;
  font-size: 0.9rem;
  color: #92400e;
}

/* Footer */
.footer {
  text-align: center;
  padding: 4rem 1rem;
  background: #fff;
  border-top: 1px solid var(--border);
}
.footer-links { margin-bottom: 1rem; display: flex; justify-content: center; gap: 1.5rem; }
.footer-links a { color: var(--text-muted); text-decoration: none; font-size: 0.9rem; }
.copyright { color: var(--text-muted); font-size: 0.85rem; }

/* Ad Space */
.ad-section { margin-top: 2rem; }
.ad-placeholder {
  height: 250px;
  background: #f1f5f9;
  border: 2px dashed var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 16px;
  color: var(--text-muted);
  font-weight: 700;
}

/* Mobile Adjustments */
@media (max-width: 640px) {
  .hero-title { font-size: 2.75rem; }
  .input-group { flex-direction: column; }
  .download-btn { padding: 1rem; width: 100%; justify-content: center; }
  .features { grid-template-columns: 1fr; }
  .container { margin-top: -2rem; }
}

.hidden { display: none !important; }