:root {
  --primary: #D4654A;
  --primary-hover: #BF5740;
  --primary-text: #B5462E;
  --accent: #3D8B8A;
  --accent-light: #E5F0F0;
  --accent-text: #2E7170;
  --surface: #FFFBF7;
  --surface-raised: #FFF7F0;
  --surface-2: #F5EFE8;
  --text: #2D2A26;
  --text-muted: #8A8480;
  --border: #E8E2DB;
  --border-strong: #D4CEC7;
  --success: #3D8B3D;
  --warning: #D4954A;
  --error: #C44B3F;
  --info: #4A7FB5;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
}
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'DM Sans', sans-serif; background: var(--surface); color: var(--text); line-height: 1.6; }
.container { max-width: 960px; margin: 0 auto; padding: 0 24px; }

/* Nav */
.site-header { border-bottom: 1px solid var(--border); background: var(--surface); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 56px; }
.nav-logo { text-decoration: none; font-family: 'Fraunces', serif; font-size: 22px; font-weight: 700; }
.logo-convert { color: var(--text); }
.logo-cal { color: var(--primary); }
.nav-links { display: flex; gap: 24px; }
.nav-links a { text-decoration: none; color: var(--text-muted); font-size: 14px; font-weight: 500; }
.nav-links a:hover { color: var(--text); }

/* Page */
.page-title { font-family: 'Fraunces', serif; font-size: clamp(28px, 5vw, 42px); font-weight: 700; line-height: 1.2; margin: 32px 0 8px; }
.page-subtitle { color: var(--text-muted); font-size: 16px; margin-bottom: 32px; }

/* Converter Card */
.converter-card { background: var(--surface-raised); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 32px; max-width: 560px; margin-bottom: 32px; }
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 14px; font-weight: 500; margin-bottom: 4px; }
.form-group select, .form-group input {
  width: 100%; padding: 8px 16px; border: 1px solid var(--border); border-radius: var(--radius-md);
  font-family: 'DM Sans', sans-serif; font-size: 16px; background: var(--surface); color: var(--text);
}
.form-group select:focus, .form-group input:focus {
  outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(212,101,74,0.12);
}

/* Result */
.result-display { background: var(--accent-light); border: 1px solid var(--accent); border-radius: var(--radius-md); padding: 16px 24px; margin-top: 24px; }
.result-number { font-family: 'Fraunces', serif; font-size: 36px; font-weight: 700; color: var(--accent-text); font-variant-numeric: tabular-nums; }
.result-unit { font-size: 14px; color: var(--text-muted); margin-top: 2px; }
.result-note { font-size: 13px; color: var(--text-muted); margin-top: 8px; padding-top: 8px; border-top: 1px solid var(--border); }

/* Buttons */
.btn { display: inline-block; padding: 8px 24px; border-radius: var(--radius-md); font-family: 'DM Sans', sans-serif; font-size: 15px; font-weight: 500; cursor: pointer; border: none; text-decoration: none; transition: all 0.15s ease-out; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-hover); }

/* Table */
.data-table { width: 100%; border-collapse: collapse; font-size: 14px; margin: 24px 0; }
.data-table th { text-align: left; padding: 8px 16px; border-bottom: 2px solid var(--border-strong); font-weight: 500; color: var(--text-muted); font-size: 12px; text-transform: uppercase; letter-spacing: 0.5px; }
.data-table td { padding: 8px 16px; border-bottom: 1px solid var(--border); font-variant-numeric: tabular-nums; }
.data-table tr:last-child td { border-bottom: none; }

/* Section */
.section { padding: 32px 0; border-top: 1px solid var(--border); margin-top: 32px; }
.section-title { font-family: 'Fraunces', serif; font-size: 24px; font-weight: 500; margin-bottom: 16px; }

/* Popular links */
.popular-list { list-style: none; columns: 2; gap: 8px; }
.popular-list li { margin-bottom: 8px; }
.popular-list a { color: var(--primary-text); text-decoration: none; font-size: 15px; }
.popular-list a:hover { text-decoration: underline; }

/* Footer */
.site-footer { border-top: 1px solid var(--border); margin-top: 48px; padding: 32px 0; background: var(--surface-2); }
.footer-content { text-align: center; }
.footer-brand { margin-bottom: 16px; }
.footer-brand p { color: var(--text-muted); font-size: 14px; margin-top: 4px; }
.footer-links { display: flex; justify-content: center; gap: 24px; margin-bottom: 16px; }
.footer-links a { color: var(--text-muted); text-decoration: none; font-size: 14px; }
.footer-links a:hover { color: var(--text); }
.footer-copy { color: var(--text-muted); font-size: 12px; }

/* Alert */
.alert { padding: 8px 16px; border-radius: var(--radius-md); font-size: 14px; margin-bottom: 16px; border-left: 3px solid; }
.alert-error { background: #fdf0ef; border-color: var(--error); color: #6b2520; }

/* Responsive */
@media (max-width: 640px) {
  .converter-card { padding: 16px; }
  .popular-list { columns: 1; }
  .nav-links { gap: 16px; }
  .nav-links a { font-size: 13px; }
}