:root {
  --bg: #0f1117;
  --bg-card: #1a1d27;
  --bg-hover: #222634;
  --text: #e8e8e8;
  --text-dim: #888;
  --accent: #5b9fff;
  --accent-dim: #3a7bd5;
  --border: #2a2e3a;
  --green: #4caf50;
  --orange: #ff9800;
  --red: #f44336;
  --radius: 10px;
}

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

body {
  font-family: -apple-system, "Segoe UI", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.8;
}

a { color: var(--accent); text-decoration: none; transition: color .2s; }
a:hover { color: #7ab8ff; }

.container { max-width: 800px; margin: 0 auto; padding: 0 20px; }

/* Nav */
.topnav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(15,17,23,0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  padding: 12px 0;
}
.nav-inner { display: flex; justify-content: space-between; align-items: center; }
.nav-logo { font-weight: 700; font-size: 1.1rem; color: var(--text); }
.nav-links { display: flex; gap: 20px; }
.nav-links a { color: var(--text-dim); font-size: 0.9rem; }
.nav-links a:hover { color: var(--text); }

/* Journal header */
.journal-header { padding: 50px 0 30px; border-bottom: 1px solid var(--border); }
.journal-header h1 { font-size: 2.2rem; margin-bottom: 8px; }
.j-desc { color: var(--text-dim); margin-bottom: 10px; }
.j-meta { font-size: 0.85rem; color: var(--text-dim); display: flex; gap: 16px; flex-wrap: wrap; }

/* Sections */
.section { padding: 30px 0; border-bottom: 1px solid var(--border); }
.section h2 { font-size: 1.4rem; margin-bottom: 12px; }
.section-desc { color: var(--text-dim); font-size: 0.9rem; margin-bottom: 16px; }

/* Review policy */
.review-policy {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 24px;
}
.review-policy summary { font-weight: 600; cursor: pointer; }
.policy-body { margin-top: 12px; color: var(--text-dim); font-size: 0.9rem; }

/* Issues */
.issues-list { display: flex; flex-direction: column; gap: 12px; }
.issue-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  transition: all .2s;
}
.issue-card:hover { border-color: var(--accent); }
.issue-card h3 { font-size: 1.1rem; margin-bottom: 6px; }
.issue-card .issue-meta { font-size: 0.8rem; color: var(--text-dim); display: flex; gap: 12px; }
.issue-card .issue-articles { margin-top: 8px; font-size: 0.85rem; color: var(--text-dim); }

/* Article list */
.article-list { display: flex; flex-direction: column; gap: 12px; }
.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  transition: all .2s;
}
.article-card:hover { border-color: var(--accent); }
.article-card h3 { font-size: 1.1rem; margin-bottom: 6px; }
.article-card .article-meta { font-size: 0.8rem; color: var(--text-dim); display: flex; gap: 12px; flex-wrap: wrap; }
.article-card .article-abstract { margin-top: 8px; font-size: 0.9rem; color: var(--text-dim); }

.loading { text-align: center; color: var(--text-dim); padding: 20px; }

/* CTA */
.cta-section { text-align: center; padding: 40px 0; }
.cta-section p { color: var(--text-dim); margin-bottom: 20px; }

/* Buttons */
.btn {
  display: inline-block; padding: 10px 24px; border-radius: var(--radius);
  font-size: 0.95rem; font-weight: 600; transition: all .2s; border: none; cursor: pointer;
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-dim); color: #fff; }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-outline { background: transparent; color: var(--accent); border: 1px solid var(--accent); }
.btn-outline:hover { background: var(--accent); color: #fff; }
.btn-sm { padding: 6px 14px; font-size: 0.85rem; }
.btn-large { padding: 14px 36px; font-size: 1.1rem; }

/* Submit page */
.submit-page { padding: 30px 0; }
.submit-page h1 { font-size: 1.8rem; margin-bottom: 8px; }

.submit-tabs { display: flex; gap: 0; margin-bottom: 24px; border-bottom: 2px solid var(--border); }
.tab-btn {
  padding: 10px 20px; background: none; border: none; color: var(--text-dim);
  font-size: 0.95rem; cursor: pointer; border-bottom: 2px solid transparent; margin-bottom: -2px;
}
.tab-btn.active { color: var(--accent); border-bottom-color: var(--accent); }

.submit-form { display: flex; flex-direction: column; gap: 18px; }
.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-weight: 600; font-size: 0.9rem; }
.form-group .required { color: var(--red); }
.form-group .form-hint { font-size: 0.8rem; color: var(--text-dim); }
.form-group input[type="text"],
.form-group input[type="email"],
.form-group textarea,
.form-group select {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: 8px;
  padding: 10px 14px; color: var(--text); font-size: 0.95rem; font-family: inherit;
}
.form-group input:focus, .form-group textarea:focus, .form-group select:focus {
  outline: none; border-color: var(--accent);
}
.form-group textarea { resize: vertical; font-family: "Consolas", "Courier New", monospace; }

.checkbox-label { display: flex; align-items: flex-start; gap: 8px; font-weight: 400; }
.checkbox-label input { margin-top: 4px; }

.form-message { padding: 10px 14px; border-radius: 8px; font-size: 0.9rem; display: none; }
.form-message.success { display: block; background: rgba(76,175,80,0.15); border: 1px solid var(--green); color: var(--green); }
.form-message.error { display: block; background: rgba(244,67,54,0.15); border: 1px solid var(--red); color: var(--red); }

/* GitHub submit info */
.github-submit-info { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.github-submit-info h3 { margin-bottom: 16px; }
.steps { padding-left: 20px; display: flex; flex-direction: column; gap: 12px; }
.steps li { font-size: 0.9rem; }
.info-box { margin-top: 16px; padding: 12px 16px; background: var(--bg-hover); border-radius: 8px; font-size: 0.85rem; }

/* Article page */
.article-page { padding: 30px 0; }
.article-title { font-size: 2rem; margin-bottom: 12px; }
.article-info { color: var(--text-dim); font-size: 0.9rem; margin-bottom: 24px; padding-bottom: 16px; border-bottom: 1px solid var(--border); }
.article-content { font-size: 1rem; line-height: 1.9; }
.article-content h1 { font-size: 1.5rem; margin: 24px 0 12px; }
.article-content h2 { font-size: 1.3rem; margin: 20px 0 10px; }
.article-content h3 { font-size: 1.1rem; margin: 16px 0 8px; }
.article-content p { margin-bottom: 14px; }
.article-content ul, .article-content ol { padding-left: 24px; margin-bottom: 14px; }
.article-content li { margin-bottom: 6px; }
.article-content code { background: var(--bg-hover); padding: 2px 8px; border-radius: 4px; font-family: "Consolas", monospace; }
.article-content pre { background: var(--bg-card); border: 1px solid var(--border); border-radius: 8px; padding: 14px; overflow-x: auto; margin-bottom: 14px; }
.article-content pre code { background: none; padding: 0; }
.article-content blockquote { border-left: 3px solid var(--accent); padding-left: 16px; margin: 14px 0; color: var(--text-dim); }
.article-content a { color: var(--accent); }
.article-content img { max-width: 100%; border-radius: 8px; }
.article-content table { border-collapse: collapse; width: 100%; margin-bottom: 14px; }
.article-content th, .article-content td { border: 1px solid var(--border); padding: 8px 12px; text-align: left; }
.article-content th { background: var(--bg-card); }
.back-link { margin-bottom: 20px; display: inline-block; font-size: 0.9rem; }

/* Footer */
.footer { text-align: center; padding: 30px 20px; color: var(--text-dim); font-size: 0.85rem; }
.footer-tech { font-family: monospace; font-size: 0.8rem; margin: 4px 0; }

@media (max-width: 640px) {
  .journal-header h1 { font-size: 1.6rem; }
  .nav-links { gap: 10px; }
  .nav-links a { font-size: 0.8rem; }
}