@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Poppins:wght@600;700;800&display=swap');

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #dbeafe;
  --accent: #7c3aed;
  --success: #059669;
  --warning: #d97706;
  --danger: #dc2626;
  --dark: #0f172a;
  --text: #1e293b;
  --muted: #64748b;
  --border: #e2e8f0;
  --bg: #f8fafc;
  --white: #ffffff;
  --card-shadow: 0 1px 3px rgba(0,0,0,.08), 0 4px 16px rgba(37,99,235,.06);
  --card-shadow-hover: 0 4px 12px rgba(0,0,0,.12), 0 8px 32px rgba(37,99,235,.12);
  --radius: 12px;
  --radius-sm: 8px;
  --transition: .2s ease;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 16px;
}

/* ── NAVBAR ── */
.navbar {
  background: rgba(255,255,255,.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: .9rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
}
.navbar-brand {
  font-family: 'Poppins', sans-serif;
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--primary) !important;
  text-decoration: none;
}
.navbar-brand span { color: var(--dark); }
.nav-link {
  color: var(--text) !important;
  font-weight: 500;
  font-size: .9rem;
  padding: .4rem .8rem !important;
  border-radius: var(--radius-sm);
  transition: background var(--transition);
}
.nav-link:hover { background: var(--primary-light); color: var(--primary) !important; }

/* ── HERO ── */
.hero {
  background: linear-gradient(135deg, #1e3a8a 0%, #2563eb 50%, #7c3aed 100%);
  padding: 5rem 0 4rem;
  color: #fff;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.04'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  pointer-events: none;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  background: rgba(255,255,255,.15);
  border: 1px solid rgba(255,255,255,.25);
  border-radius: 50px;
  padding: .3rem .9rem;
  font-size: .8rem;
  font-weight: 600;
  margin-bottom: 1.2rem;
  backdrop-filter: blur(8px);
}
.hero h1 {
  font-family: 'Poppins', sans-serif;
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
}
.hero p { font-size: 1.1rem; opacity: .88; max-width: 560px; margin-bottom: 2rem; }

/* ── SMART INPUT ── */
.smart-input-wrap {
  background: rgba(255,255,255,.12);
  border: 1px solid rgba(255,255,255,.2);
  border-radius: var(--radius);
  padding: 1.5rem;
  backdrop-filter: blur(8px);
}
.input-method-tabs { display: flex; gap: .5rem; margin-bottom: 1rem; flex-wrap: wrap; }
.input-method-tab {
  padding: .35rem .85rem;
  border: 1px solid rgba(255,255,255,.3);
  border-radius: 50px;
  background: transparent;
  color: rgba(255,255,255,.8);
  font-size: .82rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
}
.input-method-tab.active, .input-method-tab:hover {
  background: rgba(255,255,255,.2);
  color: #fff;
  border-color: rgba(255,255,255,.5);
}
.hero-input-group { display: flex; gap: .75rem; }
.hero-input-group input {
  flex: 1;
  padding: .85rem 1.2rem;
  border-radius: var(--radius-sm);
  border: none;
  font-size: .95rem;
  outline: none;
  color: var(--dark);
}
.hero-input-group input::placeholder { color: var(--muted); }
.btn-generate {
  background: var(--dark);
  color: #fff;
  border: none;
  padding: .85rem 1.8rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: .95rem;
  cursor: pointer;
  white-space: nowrap;
  transition: background var(--transition), transform var(--transition);
}
.btn-generate:hover { background: #1e293b; transform: translateY(-1px); }

/* ── MAIN TOOL SECTION ── */
.tool-section { padding: 3rem 0; }
.tool-card {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
  overflow: hidden;
}
.tool-header {
  background: linear-gradient(90deg, var(--primary) 0%, var(--accent) 100%);
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: .5rem;
}
.tool-header h2 { color: #fff; font-size: 1.05rem; font-weight: 600; margin: 0; }
.format-switcher { display: flex; gap: .3rem; }
.fmt-btn {
  padding: .25rem .7rem;
  border-radius: 50px;
  border: 1px solid rgba(255,255,255,.4);
  background: transparent;
  color: rgba(255,255,255,.8);
  font-size: .78rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
}
.fmt-btn.active { background: rgba(255,255,255,.25); color: #fff; border-color: rgba(255,255,255,.7); }
.tool-body { padding: 1.5rem; }

/* ── SOURCE TYPE GRID ── */
.source-type-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: .5rem;
  margin-bottom: 1.5rem;
}
.src-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: .25rem;
  padding: .6rem .5rem;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  cursor: pointer;
  font-size: .75rem;
  font-weight: 500;
  color: var(--muted);
  transition: all var(--transition);
  text-align: center;
}
.src-btn .src-icon { font-size: 1.4rem; line-height: 1; }
.src-btn.active, .src-btn:hover {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary);
}

/* ── FORM FIELDS ── */
.form-section { animation: fadeIn .25s ease; }
@keyframes fadeIn { from { opacity:0; transform:translateY(6px); } to { opacity:1; transform:none; } }
.form-label { font-size: .82rem; font-weight: 600; color: var(--text); margin-bottom: .35rem; display: block; }
.form-control {
  width: 100%;
  padding: .6rem .9rem;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: .9rem;
  background: var(--white);
  color: var(--text);
  transition: border-color var(--transition);
  font-family: inherit;
}
.form-control:focus { border-color: var(--primary); outline: none; box-shadow: 0 0 0 3px rgba(37,99,235,.12); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: .75rem; }
.form-row-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: .75rem; }
.form-group { margin-bottom: .85rem; }
.add-author-btn {
  display: inline-flex;
  align-items: center;
  gap: .3rem;
  font-size: .82rem;
  color: var(--primary);
  background: var(--primary-light);
  border: none;
  border-radius: var(--radius-sm);
  padding: .4rem .8rem;
  cursor: pointer;
  font-weight: 500;
  margin-top: .25rem;
  transition: background var(--transition);
}
.add-author-btn:hover { background: #bfdbfe; }
.author-row { display: flex; gap: .5rem; align-items: flex-start; margin-bottom: .5rem; }
.author-row .remove-author {
  flex-shrink: 0;
  width: 30px;
  height: 30px;
  margin-top: 6px;
  border-radius: var(--radius-sm);
  border: none;
  background: #fee2e2;
  color: var(--danger);
  cursor: pointer;
  font-size: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ── WARNINGS ── */
.citation-warning {
  display: flex;
  align-items: center;
  gap: .4rem;
  font-size: .8rem;
  color: var(--warning);
  background: #fef3c7;
  border: 1px solid #fde68a;
  border-radius: var(--radius-sm);
  padding: .4rem .7rem;
  margin-bottom: .5rem;
}

/* ── OUTPUT PANEL ── */
.output-panel {
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--card-shadow);
}
.output-header {
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.output-header h3 { font-size: .95rem; font-weight: 600; color: var(--text); margin: 0; }
.output-actions { display: flex; gap: .4rem; }
.btn-action {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  padding: .4rem .85rem;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--border);
  background: var(--white);
  font-size: .8rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: all var(--transition);
}
.btn-action:hover { border-color: var(--primary); color: var(--primary); background: var(--primary-light); }
.btn-action.success { background: #d1fae5; border-color: #6ee7b7; color: var(--success); }
.citation-output {
  padding: 1.5rem;
  min-height: 100px;
  font-family: 'Georgia', serif;
  font-size: .95rem;
  line-height: 1.8;
  color: var(--dark);
  white-space: pre-wrap;
  word-break: break-word;
}
.citation-output em { font-style: italic; }
.citation-placeholder {
  color: var(--muted);
  font-style: italic;
  font-family: 'Inter', sans-serif;
  font-size: .88rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  min-height: 100px;
}
.citation-placeholder svg { opacity: .3; }
.in-text-box {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border);
  background: var(--bg);
  border-radius: 0 0 var(--radius) var(--radius);
}
.in-text-label { font-size: .75rem; font-weight: 600; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); margin-bottom: .3rem; }
.in-text-value { font-family: 'Georgia', serif; font-size: .9rem; color: var(--dark); }

/* ── FETCH BUTTON ── */
.btn-fetch {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .55rem 1rem;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: .85rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition);
  margin-left: .4rem;
}
.btn-fetch:hover { background: var(--primary-dark); }
.btn-fetch:disabled { opacity: .6; cursor: not-allowed; }
.fetch-row { display: flex; align-items: center; }
.fetch-row .form-control { border-radius: var(--radius-sm) 0 0 var(--radius-sm); }
.fetch-row .btn-fetch { border-radius: 0 var(--radius-sm) var(--radius-sm) 0; padding: .62rem 1rem; }
.spinner { width: 14px; height: 14px; border: 2px solid rgba(255,255,255,.3); border-top-color: #fff; border-radius: 50%; animation: spin .7s linear infinite; display: inline-block; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ── BIBLIOGRAPHY ── */
.bibliography-section { padding: 2rem 0; }
.bib-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 1rem; flex-wrap: wrap; gap: .5rem; }
.bib-list { min-height: 80px; border: 2px dashed var(--border); border-radius: var(--radius); padding: .75rem; background: var(--white); }
.bib-empty { text-align: center; padding: 1.5rem; color: var(--muted); font-size: .88rem; }
.bib-item {
  display: flex;
  align-items: flex-start;
  gap: .75rem;
  padding: .75rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  margin-bottom: .5rem;
  cursor: grab;
  transition: box-shadow var(--transition);
}
.bib-item:hover { box-shadow: var(--card-shadow); }
.bib-item.sortable-ghost { opacity: .4; }
.bib-drag { color: var(--muted); font-size: 1rem; flex-shrink: 0; margin-top: 2px; }
.bib-text { flex: 1; font-family: 'Georgia', serif; font-size: .88rem; line-height: 1.7; }
.bib-remove {
  flex-shrink: 0;
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
  font-size: 1rem;
  padding: 2px 4px;
  border-radius: 4px;
  transition: color var(--transition);
}
.bib-remove:hover { color: var(--danger); background: #fee2e2; }
.bib-actions { display: flex; gap: .5rem; flex-wrap: wrap; }
.btn-export {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .45rem 1rem;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--border);
  background: var(--white);
  font-size: .83rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: all var(--transition);
}
.btn-export:hover { border-color: var(--primary); color: var(--primary); }
.btn-add-bib {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .45rem 1rem;
  border-radius: var(--radius-sm);
  border: none;
  background: var(--primary);
  color: #fff;
  font-size: .83rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition);
}
.btn-add-bib:hover { background: var(--primary-dark); }

/* ── FEATURES ── */
.features-section { padding: 4rem 0; background: var(--white); }
.section-tag { display: inline-block; background: var(--primary-light); color: var(--primary); font-size: .78rem; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; padding: .3rem .8rem; border-radius: 50px; margin-bottom: .8rem; }
.section-title { font-family: 'Poppins', sans-serif; font-size: clamp(1.5rem, 3vw, 2rem); font-weight: 700; color: var(--dark); margin-bottom: .5rem; }
.section-sub { color: var(--muted); font-size: .95rem; max-width: 540px; }
.feature-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  height: 100%;
  transition: all var(--transition);
}
.feature-card:hover { transform: translateY(-3px); box-shadow: var(--card-shadow-hover); border-color: var(--primary-light); }
.feature-icon { width: 48px; height: 48px; border-radius: 12px; background: var(--primary-light); display: flex; align-items: center; justify-content: center; font-size: 1.4rem; margin-bottom: 1rem; }
.feature-card h4 { font-size: 1rem; font-weight: 600; margin-bottom: .4rem; }
.feature-card p { font-size: .88rem; color: var(--muted); }

/* ── SOURCE TYPES SECTION ── */
.sources-section { padding: 4rem 0; }
.source-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  text-align: center;
  text-decoration: none;
  color: var(--text);
  display: block;
  height: 100%;
  transition: all var(--transition);
}
.source-card:hover { transform: translateY(-3px); box-shadow: var(--card-shadow-hover); border-color: var(--primary); color: var(--primary); text-decoration: none; }
.source-card .icon { font-size: 2rem; margin-bottom: .5rem; display: block; }
.source-card h5 { font-size: .9rem; font-weight: 600; margin-bottom: .25rem; }
.source-card p { font-size: .78rem; color: var(--muted); margin: 0; }

/* ── HOW IT WORKS ── */
.how-section { padding: 4rem 0; background: var(--white); }
.step-card { text-align: center; padding: 1.5rem 1rem; }
.step-num {
  width: 52px; height: 52px; border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff; font-weight: 700; font-size: 1.2rem;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 1rem;
}
.step-card h5 { font-weight: 600; margin-bottom: .4rem; }
.step-card p { font-size: .88rem; color: var(--muted); }

/* ── FAQ ── */
.faq-section { padding: 4rem 0; }
.accordion-item { border: 1px solid var(--border); border-radius: var(--radius) !important; margin-bottom: .6rem; overflow: hidden; }
.accordion-button {
  font-weight: 600;
  font-size: .95rem;
  color: var(--dark);
  background: var(--white);
  padding: 1rem 1.25rem;
}
.accordion-button:not(.collapsed) { background: var(--primary-light); color: var(--primary); box-shadow: none; }
.accordion-button:focus { box-shadow: none; }
.accordion-body { font-size: .9rem; color: var(--muted); line-height: 1.7; background: var(--white); }

/* ── SEO CONTENT ── */
.seo-section { padding: 4rem 0; background: var(--white); }
.seo-card { background: var(--bg); border-radius: var(--radius); padding: 2rem; border: 1px solid var(--border); }
.seo-card h2 { font-size: 1.35rem; font-weight: 700; margin-bottom: .75rem; }
.seo-card p, .seo-card li { font-size: .92rem; color: var(--muted); line-height: 1.8; }
.seo-card ul { padding-left: 1.2rem; }
.seo-card li { margin-bottom: .3rem; }

/* ── EXAMPLE CITATION BOX ── */
.example-box {
  background: linear-gradient(135deg, var(--primary-light), #ede9fe);
  border: 1px solid #bfdbfe;
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  font-family: 'Georgia', serif;
  font-size: .9rem;
  line-height: 1.8;
  margin: 1rem 0;
  position: relative;
}
.example-box::before { content: 'Example'; position: absolute; top: -10px; left: 1rem; background: var(--primary); color: #fff; font-size: .7rem; font-weight: 700; font-family: 'Inter', sans-serif; padding: .1rem .6rem; border-radius: 50px; }

/* ── FOOTER ── */
footer {
  background: var(--dark);
  color: rgba(255,255,255,.75);
  padding: 3rem 0 1.5rem;
}
.footer-brand { font-family: 'Poppins', sans-serif; font-size: 1.25rem; font-weight: 700; color: #fff; margin-bottom: .5rem; }
.footer-desc { font-size: .85rem; opacity: .7; max-width: 260px; }
.footer-links h6 { color: #fff; font-size: .82rem; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; margin-bottom: .75rem; }
.footer-links a { display: block; color: rgba(255,255,255,.65); font-size: .85rem; text-decoration: none; margin-bottom: .35rem; transition: color var(--transition); }
.footer-links a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.1); margin-top: 2rem; padding-top: 1.25rem; display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: .5rem; font-size: .82rem; }

/* ── AD SLOTS ── */
.ad-slot {
  background: var(--bg);
  border: 1px dashed var(--border);
  border-radius: var(--radius-sm);
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: .78rem;
  margin: 1.5rem 0;
}

/* ── UTILITY ── */
.badge-new { display: inline-block; background: #dcfce7; color: #166534; font-size: .7rem; font-weight: 700; padding: .1rem .5rem; border-radius: 50px; vertical-align: middle; }
.hreflang-lang { display: inline-flex; align-items: center; gap: .4rem; font-size: .8rem; color: var(--muted); margin-top: .5rem; }
.lang-link { font-size: .8rem; color: var(--primary); text-decoration: none; }
.lang-link:hover { text-decoration: underline; }

/* ── RESPONSIVE ── */
@media(max-width: 768px) {
  .hero { padding: 3rem 0 2.5rem; }
  .hero-input-group { flex-direction: column; }
  .form-row, .form-row-3 { grid-template-columns: 1fr; }
  .source-type-grid { grid-template-columns: repeat(4, 1fr); }
  .tool-body { padding: 1rem; }
  .output-header { flex-direction: column; align-items: flex-start; }
  .bib-header { flex-direction: column; align-items: flex-start; }
}
@media(max-width: 480px) {
  .source-type-grid { grid-template-columns: repeat(3, 1fr); }
  .input-method-tabs { gap: .3rem; }
  .format-switcher { flex-wrap: wrap; }
}