/* ============================================
   SnapTok — TikTok Video Downloader
   Premium dark theme with glassmorphism
   ============================================ */

/* --- Reset & Base --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #0a0a0f;
  --surface: rgba(255, 255, 255, 0.04);
  --surface-hover: rgba(255, 255, 255, 0.07);
  --border: rgba(255, 255, 255, 0.08);
  --border-focus: rgba(255, 255, 255, 0.18);
  --text: #e8e8ed;
  --text-muted: #8e8e99;
  --text-dim: #5a5a66;
  --accent-pink: #ff2d55;
  --accent-cyan: #25f4ee;
  --accent-gradient: linear-gradient(135deg, #ff2d55, #fe2c8d, #25f4ee);
  --glass-bg: rgba(20, 20, 30, 0.6);
  --glass-border: rgba(255, 255, 255, 0.06);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.5);
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
}

/* --- Animated Background --- */
.bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 60px 60px;
  z-index: 0;
  pointer-events: none;
}

.blob {
  position: fixed;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.35;
  z-index: 0;
  pointer-events: none;
  animation: blobFloat 20s ease-in-out infinite alternate;
}

.blob-1 {
  width: 500px;
  height: 500px;
  background: var(--accent-pink);
  top: -150px;
  left: -100px;
  animation-delay: 0s;
}

.blob-2 {
  width: 400px;
  height: 400px;
  background: var(--accent-cyan);
  bottom: -100px;
  right: -80px;
  animation-delay: -7s;
}

.blob-3 {
  width: 300px;
  height: 300px;
  background: #8b5cf6;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  opacity: 0.15;
  animation-delay: -14s;
}

@keyframes blobFloat {
  0% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(40px, -30px) scale(1.05); }
  66% { transform: translate(-20px, 20px) scale(0.95); }
  100% { transform: translate(30px, -10px) scale(1.02); }
}

/* --- Layout --- */
main {
  position: relative;
  z-index: 1;
  max-width: 720px;
  margin: 0 auto;
  padding: 60px 24px 40px;
}

/* --- Hero --- */
.hero {
  text-align: center;
  margin-bottom: 48px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 32px;
}

.logo-icon {
  flex-shrink: 0;
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 16px;
}

.gradient-text {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 420px;
  margin: 0 auto;
}

/* --- Download Card --- */
.download-card {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 32px;
  backdrop-filter: blur(40px);
  -webkit-backdrop-filter: blur(40px);
  box-shadow: var(--shadow-lg);
  margin-bottom: 64px;
}

/* --- Input Group --- */
.input-group {
  display: flex;
  gap: 12px;
}

.input-wrapper {
  flex: 1;
  position: relative;
  display: flex;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: border-color 0.2s, box-shadow 0.2s;
}

.input-wrapper:focus-within {
  border-color: var(--accent-pink);
  box-shadow: 0 0 0 3px rgba(255, 45, 85, 0.15);
}

.input-icon {
  position: absolute;
  left: 14px;
  color: var(--text-dim);
  flex-shrink: 0;
  pointer-events: none;
}

#urlInput {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text);
  font-family: var(--font);
  font-size: 0.95rem;
  padding: 14px 14px 14px 44px;
  min-width: 0;
}

#urlInput::placeholder {
  color: var(--text-dim);
}

.paste-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-family: var(--font);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  padding: 8px 14px;
  border-radius: 8px;
  white-space: nowrap;
  transition: color 0.2s, background 0.2s;
  flex-shrink: 0;
}

.paste-btn:hover {
  color: var(--text);
  background: rgba(255,255,255,0.06);
}

.submit-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--accent-gradient);
  border: none;
  border-radius: var(--radius-sm);
  color: #fff;
  font-family: var(--font);
  font-size: 0.95rem;
  font-weight: 600;
  padding: 14px 28px;
  cursor: pointer;
  white-space: nowrap;
  transition: transform 0.15s, box-shadow 0.15s, opacity 0.15s;
  flex-shrink: 0;
}

.submit-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 24px rgba(255, 45, 85, 0.3);
}

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

.submit-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

/* Spinner */
.spinner {
  display: inline-block;
  width: 18px;
  height: 18px;
  border: 2.5px 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); }
}

/* --- Error --- */
.error-msg {
  margin-top: 16px;
  padding: 12px 16px;
  background: rgba(255, 45, 85, 0.1);
  border: 1px solid rgba(255, 45, 85, 0.2);
  border-radius: var(--radius-sm);
  color: #ff6b8a;
  font-size: 0.9rem;
  animation: fadeIn 0.3s ease;
}

/* --- Preview --- */
.preview {
  margin-top: 24px;
  animation: fadeSlideUp 0.4s ease;
}

.preview-card {
  display: flex;
  gap: 16px;
  align-items: center;
  padding: 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
}

.preview-thumb {
  width: 80px;
  height: 80px;
  object-fit: cover;
  border-radius: var(--radius-sm);
  background: var(--surface-hover);
  flex-shrink: 0;
}

.preview-info {
  flex: 1;
  min-width: 0;
}

.preview-title {
  font-size: 0.95rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  margin-bottom: 4px;
}

.preview-author {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 2px;
}

.preview-duration {
  font-size: 0.8rem;
  color: var(--text-dim);
}

.download-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: 100%;
  padding: 16px;
  background: linear-gradient(135deg, #25f4ee, #00c9b7);
  border: none;
  border-radius: var(--radius-sm);
  color: #0a0a0f;
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
}

.download-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(37, 244, 238, 0.3);
}

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

/* --- How It Works --- */
.how-it-works {
  margin-bottom: 64px;
}

.how-it-works h2 {
  text-align: center;
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 32px;
  letter-spacing: -0.02em;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.step {
  text-align: center;
  padding: 28px 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: border-color 0.3s, transform 0.3s;
}

.step:hover {
  border-color: var(--border-focus);
  transform: translateY(-4px);
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--accent-gradient);
  color: #fff;
  font-weight: 700;
  font-size: 1rem;
  margin-bottom: 16px;
}

.step h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.step p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* --- Footer --- */
footer {
  text-align: center;
  padding: 24px 0;
  border-top: 1px solid var(--border);
}

footer p {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* --- Animations --- */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes fadeSlideUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* --- Responsive --- */
@media (max-width: 600px) {
  main {
    padding: 40px 16px 32px;
  }

  .download-card {
    padding: 20px;
  }

  .input-group {
    flex-direction: column;
  }

  .submit-btn {
    width: 100%;
    justify-content: center;
  }

  .steps {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .preview-card {
    flex-direction: column;
    text-align: center;
  }

  .preview-thumb {
    width: 120px;
    height: 120px;
  }
}