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

:root {
  --bg-1: #0f172a;
  --bg-2: #1e293b;
  --card: rgba(255, 255, 255, 0.08);
  --card-2: rgba(255, 255, 255, 0.05);
  --border: rgba(255, 255, 255, 0.12);
  --text: #ffffff;
  --muted: #cbd5e1;
  --blue: #2563eb;
  --blue-hover: #1d4ed8;
  --slate: #334155;
  --slate-hover: #475569;
  --danger: #dc2626;
  --danger-hover: #b91c1c;
  --success: #86efac;
  --error: #fca5a5;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: Arial, sans-serif;
  background: linear-gradient(135deg, var(--bg-1), var(--bg-2));
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

.container {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.nav {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.logo {
  color: white;
  text-decoration: none;
  font-size: 1.45rem;
  font-weight: 700;
  letter-spacing: 0.3px;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  transition: 0.2s ease;
}

.nav-links a:hover,
.nav-links a.active {
  color: white;
}

.hero {
  text-align: center;
  padding: 56px 0 30px;
}

.hero-badge {
  display: inline-block;
  margin-bottom: 16px;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(37, 99, 235, 0.18);
  border: 1px solid rgba(96, 165, 250, 0.3);
  color: #dbeafe;
  font-size: 0.95rem;
}

.hero h1 {
  font-size: 2.7rem;
  line-height: 1.15;
  margin-bottom: 16px;
}

.hero-text {
  max-width: 760px;
  margin: 0 auto;
  color: var(--muted);
  font-size: 1.06rem;
  line-height: 1.8;
}

.hero-points {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.hero-points span {
  padding: 10px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  color: #e2e8f0;
  font-size: 0.95rem;
}

.tool-card,
.page-card,
.info-card,
.step-card,
.audience-card,
.article-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 18px;
  backdrop-filter: blur(10px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.22);
}

.tool-card {
  padding: 24px;
}

.upload-section {
  margin-bottom: 28px;
}

.upload-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 190px;
  border-radius: 18px;
  border: 2px dashed rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.04);
  cursor: pointer;
  text-align: center;
  padding: 20px;
  transition: 0.25s ease;
}

.upload-box:hover {
  border-color: #60a5fa;
  background: rgba(96, 165, 250, 0.08);
}

.upload-icon {
  font-size: 2.8rem;
  margin-bottom: 10px;
}

.upload-text {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.upload-subtext {
  color: var(--muted);
  font-size: 0.96rem;
}

.options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.input-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.input-group label {
  color: #e2e8f0;
  font-size: 0.95rem;
}

.input-group input,
.input-group select {
  padding: 12px 14px;
  border-radius: 12px;
  border: none;
  outline: none;
  font-size: 1rem;
}

.buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
}

button {
  border: none;
  cursor: pointer;
  padding: 12px 18px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 700;
  transition: 0.2s ease;
}

#convertBtn {
  background: var(--blue);
  color: white;
}

#convertBtn:hover {
  background: var(--blue-hover);
}

.secondary {
  background: var(--slate);
  color: white;
}

.secondary:hover {
  background: var(--slate-hover);
}

.note {
  margin-top: 14px;
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

.section-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}

.section-top h2 {
  font-size: 1.2rem;
}

.section-top span {
  color: var(--muted);
}

.preview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(185px, 1fr));
  gap: 16px;
}

.preview-item {
  background: rgba(255, 255, 255, 0.06);
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.preview-image {
  width: 100%;
  height: 185px;
  object-fit: cover;
  display: block;
  background: #0f172a;
}

.preview-info {
  padding: 10px;
}

.preview-name {
  font-size: 0.9rem;
  word-break: break-word;
  margin-bottom: 8px;
  color: #f8fafc;
  line-height: 1.5;
}

.preview-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
}

.preview-index {
  font-size: 0.85rem;
  color: var(--muted);
}

.remove-btn {
  background: var(--danger);
  color: white;
  padding: 8px 10px;
  font-size: 0.85rem;
  border-radius: 8px;
}

.remove-btn:hover {
  background: var(--danger-hover);
}

.message {
  margin-top: 18px;
  font-size: 0.95rem;
  min-height: 24px;
  color: #fde68a;
}

.success {
  color: var(--success);
}

.error {
  color: var(--error);
}

.content-section {
  margin-top: 34px;
}

.section-heading {
  text-align: center;
  margin-bottom: 22px;
}

.section-heading h2 {
  font-size: 2rem;
  margin-bottom: 10px;
}

.section-heading p {
  color: var(--muted);
  line-height: 1.7;
}

.step-grid,
.info-grid,
.article-grid,
.audience-grid {
  display: grid;
  gap: 18px;
}

.step-grid {
  grid-template-columns: repeat(3, 1fr);
}

.step-card {
  padding: 22px;
}

.step-number {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: rgba(37, 99, 235, 0.2);
  color: #dbeafe;
  font-weight: 700;
  margin-bottom: 14px;
}

.step-card h3,
.info-card h3,
.article-card h3 {
  margin-bottom: 10px;
}

.step-card p,
.info-card p,
.article-card p,
.faq-item p,
.page-card p,
.article-page p,
.article-page li {
  color: #dbe4f0;
  line-height: 1.8;
}

.info-grid {
  grid-template-columns: repeat(3, 1fr);
}

.info-card {
  padding: 22px;
}

.audience-grid {
  grid-template-columns: repeat(3, 1fr);
}

.audience-card {
  padding: 18px;
  text-align: center;
  font-weight: 700;
}

.article-grid {
  grid-template-columns: repeat(3, 1fr);
}

.article-card {
  padding: 22px;
  text-decoration: none;
  color: white;
  transition: transform 0.18s ease, border-color 0.18s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: rgba(96, 165, 250, 0.35);
}

.faq-preview {
  display: grid;
  gap: 16px;
}

.faq-item {
  padding: 18px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.faq-item h3 {
  margin-bottom: 8px;
}

.page-content {
  padding: 44px 0;
}

.page-card,
.article-page {
  max-width: 900px;
  margin: 0 auto;
  padding: 30px;
}

.page-card h1,
.article-page h1 {
  font-size: 2rem;
  margin-bottom: 18px;
}

.article-page h2 {
  font-size: 1.45rem;
  margin: 26px 0 12px;
}

.article-page ul,
.article-page ol {
  padding-left: 20px;
  margin: 10px 0 18px;
}

.article-meta {
  color: var(--muted);
  margin-bottom: 18px;
  font-size: 0.95rem;
}

.contact-box {
  margin: 18px 0;
  padding: 18px;
  border-radius: 14px;
  background: var(--card-2);
}

.site-footer {
  margin-top: 42px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(15, 23, 42, 0.75);
}

.footer-content {
  min-height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-content p {
  color: var(--muted);
}

.footer-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--muted);
  text-decoration: none;
}

.footer-links a:hover {
  color: white;
}

@media (max-width: 980px) {
  .step-grid,
  .info-grid,
  .article-grid,
  .audience-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 700px) {
  .nav {
    padding: 14px 0;
    align-items: flex-start;
    flex-direction: column;
  }

  .hero {
    padding-top: 42px;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .tool-card,
  .page-card,
  .article-page {
    padding: 18px;
  }

  .step-grid,
  .info-grid,
  .article-grid,
  .audience-grid {
    grid-template-columns: 1fr;
  }

  .footer-content {
    padding: 16px 0;
  }
}