/* ============================================================
   RESET & ROOT
============================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #0a0b14;
  --bg-2: #0f1020;
  --bg-card: rgba(255,255,255,0.04);
  --bg-card-hover: rgba(255,255,255,0.07);
  --border: rgba(255,255,255,0.08);
  --border-active: rgba(99,102,241,0.5);

  --indigo: #6366f1;
  --indigo-light: #818cf8;
  --violet: #8b5cf6;
  --emerald: #10b981;
  --amber: #f59e0b;
  --rose: #f43f5e;

  --text: #f1f5f9;
  --text-2: #94a3b8;
  --text-3: #64748b;

  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 48px rgba(0,0,0,0.5);

  --font: 'Inter', system-ui, sans-serif;
  --transition: 0.2s cubic-bezier(0.4,0,0.2,1);
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* ============================================================
   CONTAINER
============================================================ */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ============================================================
   HEADER
============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10,11,20,0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--text);
  transition: opacity var(--transition);
}
.logo:hover { opacity: 0.8; }

.header-nav {
  display: flex;
  gap: 32px;
}
.header-nav a {
  color: var(--text-2);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition);
}
.header-nav a:hover { color: var(--text); }

/* ============================================================
   HERO
============================================================ */
.hero {
  position: relative;
  overflow: hidden;
  padding: 80px 0 60px;
  text-align: center;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.25;
}
.hero-orb-1 {
  width: 500px; height: 500px;
  background: var(--indigo);
  top: -200px; left: -100px;
  animation: pulse 8s ease-in-out infinite;
}
.hero-orb-2 {
  width: 400px; height: 400px;
  background: var(--violet);
  top: -100px; right: -100px;
  animation: pulse 8s ease-in-out infinite 2s;
}
.hero-orb-3 {
  width: 300px; height: 300px;
  background: var(--emerald);
  bottom: -100px; left: 50%;
  transform: translateX(-50%);
  animation: pulse 8s ease-in-out infinite 4s;
}

@keyframes pulse {
  0%, 100% { opacity: 0.2; transform: scale(1); }
  50% { opacity: 0.35; transform: scale(1.05); }
}

.hero-content { position: relative; }

.hero-badge {
  display: inline-block;
  background: rgba(99,102,241,0.15);
  border: 1px solid rgba(99,102,241,0.3);
  color: var(--indigo-light);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 20px;
}

.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  font-weight: 800;
  line-height: 1.1;
  background: linear-gradient(135deg, #fff 0%, var(--indigo-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 20px;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: var(--text-2);
  max-width: 600px;
  margin: 0 auto;
}

/* ============================================================
   AD ZONES
============================================================ */
.ad-zone {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 12px 0;
}

.ad-label {
  font-size: 0.65rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.ad-placeholder {
  width: 100%;
  max-width: 728px;
  height: 90px;
  background: rgba(255,255,255,0.025);
  border: 1px dashed rgba(255,255,255,0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-3);
  font-size: 0.75rem;
}

.ad-placeholder--tall {
  max-width: 300px;
  height: 600px;
}

.ad-zone--sidebar .ad-placeholder {
  max-width: 300px;
  height: 250px;
}

.ad-zone--leaderboard {
  background: rgba(0,0,0,0.2);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.ad-zone--in-content {
  margin: 32px 0;
  border-radius: var(--radius);
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border);
  padding: 16px;
}

/* ============================================================
   MAIN LAYOUT
============================================================ */
.main-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 32px;
  padding-top: 32px;
  padding-bottom: 64px;
  align-items: start;
}

.calc-column { min-width: 0; }

.sidebar-column {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.sticky-ad { position: sticky; top: 84px; }

/* ============================================================
   CARDS
============================================================ */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 24px;
  backdrop-filter: blur(10px);
  transition: border-color var(--transition);
}
.card:hover { border-color: rgba(255,255,255,0.12); }

.card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 20px;
  letter-spacing: -0.01em;
}

/* ============================================================
   LOAN TYPE TABS
============================================================ */
.loan-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.loan-tab {
  flex: 1;
  min-width: 100px;
  padding: 10px 16px;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-2);
  font-family: var(--font);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
}
.loan-tab:hover {
  background: rgba(255,255,255,0.07);
  color: var(--text);
}
.loan-tab.active {
  background: rgba(99,102,241,0.15);
  border-color: var(--border-active);
  color: var(--indigo-light);
}

/* ============================================================
   INPUTS
============================================================ */
.input-group {
  margin-bottom: 28px;
}
.input-group:last-of-type { margin-bottom: 24px; }

.input-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.input-row label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-2);
}

.input-value-box {
  display: flex;
  align-items: center;
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 6px 12px;
  gap: 6px;
  transition: border-color var(--transition);
}
.input-value-box:focus-within { border-color: var(--border-active); }

.input-value-box input {
  background: none;
  border: none;
  outline: none;
  color: var(--text);
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 600;
  width: 100px;
  text-align: right;
}

.currency-symbol {
  color: var(--text-3);
  font-size: 0.875rem;
  font-weight: 500;
}

/* Range Slider */
.slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  border-radius: 100px;
  background: rgba(255,255,255,0.1);
  outline: none;
  cursor: pointer;
}
.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--indigo), var(--violet));
  cursor: pointer;
  box-shadow: 0 0 0 3px rgba(99,102,241,0.2);
  transition: box-shadow var(--transition);
}
.slider::-webkit-slider-thumb:hover {
  box-shadow: 0 0 0 6px rgba(99,102,241,0.2);
}
.slider::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--indigo), var(--violet));
  cursor: pointer;
  border: none;
}

.slider-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 6px;
  font-size: 0.7rem;
  color: var(--text-3);
}

/* Calculate Button */
.btn-calculate {
  width: 100%;
  padding: 14px 24px;
  background: linear-gradient(135deg, var(--indigo) 0%, var(--violet) 100%);
  border: none;
  border-radius: var(--radius-sm);
  color: #fff;
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  box-shadow: 0 4px 20px rgba(99,102,241,0.4);
}
.btn-calculate:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 28px rgba(99,102,241,0.5);
}
.btn-calculate:active { transform: translateY(0); }

/* ============================================================
   RESULTS
============================================================ */
.results-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 24px;
}

.result-item {
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px;
}

.result-item--primary {
  grid-column: 1 / -1;
  background: linear-gradient(135deg, rgba(99,102,241,0.1) 0%, rgba(139,92,246,0.1) 100%);
  border-color: rgba(99,102,241,0.3);
  text-align: center;
  padding: 24px;
}

.result-label {
  font-size: 0.75rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 8px;
}

.result-value {
  font-size: 2.4rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.02em;
}
.result-value--sm { font-size: 1.5rem; }
.result-value--accent { color: var(--indigo-light); }

/* Cost Breakdown Bar */
.cost-breakdown { margin-top: 8px; }

.breakdown-bar {
  display: flex;
  height: 8px;
  border-radius: 100px;
  overflow: hidden;
  margin-bottom: 10px;
}
.bar-principal {
  background: linear-gradient(90deg, var(--indigo), var(--indigo-light));
  transition: width 0.5s ease;
}
.bar-interest {
  background: linear-gradient(90deg, var(--violet), #a78bfa);
  transition: width 0.5s ease;
}

.breakdown-legend {
  display: flex;
  gap: 20px;
  font-size: 0.8rem;
  color: var(--text-2);
  align-items: center;
}
.legend-dot {
  display: inline-block;
  width: 10px; height: 10px;
  border-radius: 50%;
  margin-right: 6px;
}
.legend-dot--principal { background: var(--indigo); }
.legend-dot--interest { background: var(--violet); }

/* ============================================================
   CHARTS
============================================================ */
.chart-tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 24px;
  background: rgba(255,255,255,0.04);
  border-radius: var(--radius-sm);
  padding: 4px;
}

.chart-tab {
  flex: 1;
  padding: 8px 12px;
  background: none;
  border: none;
  border-radius: 8px;
  color: var(--text-2);
  font-family: var(--font);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}
.chart-tab:hover { color: var(--text); }
.chart-tab.active {
  background: rgba(99,102,241,0.2);
  color: var(--indigo-light);
}

.chart-container {
  position: relative;
  height: 300px;
}
.chart-container canvas { max-height: 300px; }

/* ============================================================
   AMORTIZATION TABLE
============================================================ */
.amort-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.amort-desc {
  font-size: 0.875rem;
  color: var(--text-2);
  margin-bottom: 20px;
}

.btn-export {
  padding: 8px 16px;
  background: rgba(16,185,129,0.1);
  border: 1px solid rgba(16,185,129,0.3);
  border-radius: var(--radius-sm);
  color: var(--emerald);
  font-family: var(--font);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
}
.btn-export:hover {
  background: rgba(16,185,129,0.2);
}

.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
}

thead {
  background: rgba(255,255,255,0.04);
}

th {
  padding: 12px 16px;
  text-align: right;
  font-weight: 600;
  font-size: 0.75rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  white-space: nowrap;
}
th:first-child, th:nth-child(2) { text-align: left; }

td {
  padding: 11px 16px;
  text-align: right;
  color: var(--text-2);
  border-top: 1px solid rgba(255,255,255,0.04);
}
td:first-child, td:nth-child(2) { text-align: left; color: var(--text-3); }

tbody tr:hover { background: rgba(255,255,255,0.03); }

.td-principal { color: var(--indigo-light) !important; font-weight: 500; }
.td-interest  { color: #a78bfa !important; }
.td-balance   { color: var(--text) !important; font-weight: 600; }

/* Pagination */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-top: 20px;
}

.page-btn {
  padding: 8px 18px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-2);
  font-family: var(--font);
  font-size: 0.875rem;
  cursor: pointer;
  transition: all var(--transition);
}
.page-btn:hover:not(:disabled) {
  background: rgba(99,102,241,0.15);
  border-color: var(--border-active);
  color: var(--indigo-light);
}
.page-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.page-info {
  font-size: 0.875rem;
  color: var(--text-2);
  min-width: 100px;
  text-align: center;
}

/* ============================================================
   CONTENT SECTIONS
============================================================ */
.content-section {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px;
  margin-bottom: 24px;
}

.content-section h2 {
  font-size: 1.6rem;
  font-weight: 800;
  margin-bottom: 16px;
  background: linear-gradient(135deg, var(--text) 0%, var(--indigo-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.content-section h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text);
  margin: 24px 0 10px;
}

.content-section p {
  color: var(--text-2);
  font-size: 0.95rem;
  line-height: 1.75;
}

.info-box {
  background: rgba(99,102,241,0.08);
  border: 1px solid rgba(99,102,241,0.25);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  color: var(--indigo-light);
  font-size: 0.9rem;
  margin-top: 20px;
}

.formula-box {
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  margin-top: 12px;
  font-size: 0.9rem;
}
.formula-box strong {
  display: block;
  font-size: 1.1rem;
  color: var(--text);
  margin-bottom: 14px;
  font-family: 'Courier New', monospace;
}
.formula-box ul { padding-left: 20px; }
.formula-box li {
  color: var(--text-2);
  margin-bottom: 6px;
}

/* ============================================================
   FAQ
============================================================ */
.faq-list { display: flex; flex-direction: column; gap: 8px; }

.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color var(--transition);
}
.faq-item:hover { border-color: rgba(255,255,255,0.12); }

.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  background: rgba(255,255,255,0.03);
  border: none;
  color: var(--text);
  font-family: var(--font);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
  transition: background var(--transition);
}
.faq-question:hover { background: rgba(255,255,255,0.06); }

.faq-icon {
  font-size: 1.4rem;
  color: var(--indigo-light);
  transition: transform var(--transition);
  flex-shrink: 0;
  margin-left: 12px;
}
.faq-question[aria-expanded="true"] .faq-icon { transform: rotate(45deg); }

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.2s ease;
}
.faq-answer.open {
  max-height: 300px;
  padding: 0 20px 16px;
}
.faq-answer p {
  color: var(--text-2);
  font-size: 0.9rem;
  line-height: 1.7;
  padding-top: 10px;
}

/* ============================================================
   SIDEBAR WIDGETS
============================================================ */
.widget-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
}

.widget-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 14px;
}

.tips-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.tips-list li {
  font-size: 0.825rem;
  color: var(--text-2);
  line-height: 1.5;
  padding-left: 16px;
  position: relative;
}
.tips-list li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--indigo-light);
  font-weight: 700;
}

/* ============================================================
   FOOTER
============================================================ */
.site-footer {
  background: var(--bg-2);
  border-top: 1px solid var(--border);
  padding: 36px 0;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  text-align: center;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
}

.footer-disclaimer {
  max-width: 640px;
  font-size: 0.8rem;
  color: var(--text-3);
  line-height: 1.6;
}

.footer-copyright {
  font-size: 0.8rem;
  color: var(--text-3);
}

/* ============================================================
   ANIMATIONS
============================================================ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}
.card { animation: fadeInUp 0.4s ease both; }

/* ============================================================
   RESPONSIVE
============================================================ */
@media (max-width: 1024px) {
  .main-layout {
    grid-template-columns: 1fr;
  }
  .sidebar-column {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }
  .sticky-ad { position: static; }
}

@media (max-width: 640px) {
  .header-nav { display: none; }
  .hero { padding: 48px 0 40px; }
  .loan-tabs { flex-wrap: wrap; }
  .loan-tab { min-width: calc(50% - 4px); }
  .results-grid { grid-template-columns: 1fr; }
  .result-item--primary { grid-column: 1; }
  .chart-tabs { flex-direction: column; }
  .content-section { padding: 24px 20px; }
  .sidebar-column { grid-template-columns: 1fr; }
}