:root {
  --bg: #f4f7fb;
  --surface: #ffffff;
  --surface-muted: #eef3fb;
  --text: #121a2b;
  --text-soft: #4f5b75;
  --primary: #2446ff;
  --primary-strong: #1832c2;
  --accent: #19b394;
  --border: #dbe2f0;
  --shadow-sm: 0 8px 24px rgba(9, 27, 70, 0.08);
  --shadow-md: 0 18px 42px rgba(10, 31, 72, 0.14);
  --radius-sm: 12px;
  --radius-md: 18px;
  --radius-lg: 26px;
  --space-1: clamp(.55rem,.5rem + .2vw,.75rem);
  --space-2: clamp(.85rem,.7rem + .5vw,1.2rem);
  --space-3: clamp(1.2rem,1rem + .7vw,1.6rem);
  --space-4: clamp(1.7rem,1.2rem + 1.4vw,2.5rem);
  --space-5: clamp(2.5rem,1.8rem + 2.4vw,4.2rem);
  --font-sans: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
  --font-serif: "DM Serif Display", Georgia, serif;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; font-family: var(--font-sans); background: var(--bg); color: var(--text); }
a { color: inherit; }
a:focus-visible, button:focus-visible, input:focus-visible, summary:focus-visible { outline: 3px solid color-mix(in oklab, var(--primary), white 25%); outline-offset: 2px; }
img { max-width: 100%; display: block; }
.container { width: min(1140px, calc(100% - 2rem)); margin-inline: auto; }
.section { padding: var(--space-5) 0; }
.section.alt { background: var(--surface); }
.section-head h2, h1, h2 { line-height: 1.15; letter-spacing: -.02em; }
h1, h2 { font-family: var(--font-serif); }
h1 { font-size: clamp(2rem, 1.35rem + 2.7vw, 3.8rem); }
h2 { font-size: clamp(1.6rem, 1.15rem + 1.6vw, 2.7rem); margin: 0 0 .8rem; }
p { font-size: clamp(1rem, .95rem + .3vw, 1.1rem); color: var(--text-soft); margin: 0 0 1rem; }
.btn { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; border-radius: 999px; padding: .75rem 1.3rem; font-weight: 600; border: 1px solid transparent; text-decoration: none; gap: .5rem; }
.btn.primary { background: var(--primary); color: #fff; }
.btn.primary:hover { background: var(--primary-strong); }
.btn.secondary { background: var(--surface); border-color: var(--border); }
.btn.ghost { border-color: color-mix(in oklab, var(--primary), white 65%); color: var(--primary-strong); }
.badge { display:inline-flex; padding:.3rem .8rem; border-radius:999px; font-size:.84rem; background: color-mix(in oklab, var(--primary), white 88%); color:var(--primary-strong); font-weight:600; }
.site-header { position: sticky; top: 0; z-index: 30; backdrop-filter: blur(12px); background: color-mix(in oklab, var(--bg), white 25%); border-bottom: 1px solid var(--border); }
.site-header__bar { display:flex; align-items:center; justify-content:space-between; min-height:72px; gap:1rem; }
.brand { font-weight: 800; text-decoration:none; }
.site-nav { display:flex; gap:1rem; align-items:center; }
.site-nav a { text-decoration:none; color:var(--text-soft); font-weight:600; }
.site-nav a:hover { color: var(--text); }
.mobile-toggle { display:none; min-width:44px; min-height:44px; border:1px solid var(--border); border-radius:10px; background:#fff; }
.hero { display:grid; gap:var(--space-4); grid-template-columns: 1.2fr 1fr; align-items:center; }
.hero-card, .card { background:var(--surface); border:1px solid var(--border); border-radius: var(--radius-md); box-shadow:var(--shadow-sm); }
.hero-card { padding: var(--space-4); }
.hero-actions { display:flex; flex-wrap:wrap; gap:.8rem; }
.stats { display:grid; grid-template-columns:repeat(3,minmax(0,1fr)); gap:.8rem; }
.stats .card { padding:1rem; }
.stats strong { display:block; font-size:1.3rem; }
.grid { display:grid; gap:1rem; }
.grid.cols-3 { grid-template-columns: repeat(3,minmax(0,1fr)); }
.grid.cols-2 { grid-template-columns: repeat(2,minmax(0,1fr)); }
.card { padding:1.1rem; }
.quote-card { border-left: 3px solid var(--accent); }
.principle-icon { width:40px; height:40px; border-radius: 12px; background: var(--surface-muted); display:grid; place-items:center; margin-bottom:.7rem; }
.number-list { margin:0; padding-left:1.2rem; display:grid; gap:.7rem; }
.edu-icon { width:58px; aspect-ratio:1; transform: rotate(45deg); background:var(--surface-muted); border-radius:12px; display:grid; place-items:center; margin-bottom:1rem; }
.edu-icon > span { transform: rotate(-45deg); font-weight:700; color:var(--primary); }
.article-card { overflow:hidden; padding:0; }
.article-card img { aspect-ratio: 16/9; object-fit:cover; }
.article-card__body { padding:1rem; }
.flash-card-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(170px,1fr)); gap:.9rem; }
.flash-card { background:var(--surface); border:1px solid var(--border); border-radius:14px; padding:.8rem; min-height: 190px; text-decoration:none; }
.flash-card p { font-size:.9rem; margin-bottom:.5rem; }
.flash-card img { width:56px; height:56px; object-fit:contain; margin-bottom:.7rem; }
.site-footer { background:#0e1730; color:#d8dded; padding:2.8rem 0; }
.site-footer a { color:#fff; opacity:.9; text-decoration:none; }
.drawer { position: fixed; inset:0; display:none; }
.drawer[aria-hidden="false"] { display:block; }
.drawer__backdrop { position:absolute; inset:0; background:rgba(7,11,24,.45); }
.drawer__panel { position: absolute; right:0; top:0; bottom:0; width:min(84vw,360px); background:#fff; padding:1rem; display:grid; align-content:start; gap:.8rem; }
.calculator-layout { display:grid; grid-template-columns: 1.05fr .95fr; gap:1rem; }
.calculator-form .input-group { margin-bottom:.9rem; }
.calculator-form label { display:block; font-weight:600; margin-bottom:.4rem; color:var(--text); }
.calculator-form input { width:100%; min-height:44px; border:1px solid var(--border); border-radius:12px; padding:.6rem .75rem; }
.calculator-sticky-summary { position: sticky; bottom: .5rem; display:none; }
.faq details { background:var(--surface); border:1px solid var(--border); border-radius:12px; padding:.8rem .95rem; }
.faq details + details { margin-top:.6rem; }
@media (max-width: 992px) {
  .hero, .calculator-layout, .grid.cols-3, .grid.cols-2 { grid-template-columns: 1fr; }
  .site-nav { display:none; }
  .mobile-toggle { display:inline-grid; place-items:center; }
  .calculator-sticky-summary { display:flex; justify-content:space-between; align-items:center; background:#0f1933; color:#fff; border-radius:14px; padding:.8rem 1rem; gap:.7rem; }
}
@media (max-width: 480px) { .container { width: min(1140px, calc(100% - 1.1rem)); } }
.mc-modal,.mc-bottom-sheet{position:fixed;inset:0;display:none;z-index:50}.mc-modal--open,.mc-bottom-sheet--open{display:block}.mc-modal__overlay,.mc-bottom-sheet__overlay{position:absolute;inset:0;background:rgba(9,16,35,.56)}.mc-modal__dialog,.mc-bottom-sheet__panel{position:relative;background:#fff;border-radius:16px;padding:1rem;width:min(92vw,520px);margin:8vh auto;z-index:1}.mc-bottom-sheet__panel{width:min(96vw,760px)}.mc-modal__close,.mc-bottom-sheet__close{position:absolute;top:.5rem;right:.5rem;min-width:44px;min-height:44px;border:1px solid var(--border);background:#fff;border-radius:10px}

/* Flashcards (legacy structure styled in new system) */
.flashcards .major { margin-bottom: .8rem; }
.flash-card { perspective: 1000px; min-height: 220px; background: transparent; border: 0; padding: 0; }
.flash-card-inner { position: relative; height: 100%; min-height: 220px; transform-style: preserve-3d; transition: transform .45s ease; }
.flash-card:hover .flash-card-inner,
.flash-card:focus-within .flash-card-inner,
.flash-card:focus .flash-card-inner { transform: rotateY(180deg); }
.flash-card-front,
.flash-card-back { position: absolute; inset: 0; backface-visibility: hidden; border: 1px solid var(--border); border-radius: 14px; background: var(--surface); box-shadow: var(--shadow-sm); padding: .9rem; display: flex; flex-direction: column; justify-content: center; gap: .5rem; }
.flash-card-front .image { display:flex; justify-content:center; }
.flash-card-front img { width: 64px; height: 64px; object-fit: contain; margin: 0 auto; }
.flash-card-back { transform: rotateY(180deg); }
.flash-card .tagline { font-size: .88rem; margin: 0; }
.button.small { display:inline-flex; align-items:center; justify-content:center; min-height:44px; padding:.55rem .9rem; border-radius: 999px; text-decoration:none; background:var(--primary); color:#fff; font-weight:600; }
@media (max-width: 992px) {
  .flash-card { min-height: 210px; }
  .flash-card-inner { min-height: 210px; }
}