/* Calme — kiểu dáng dùng chung cho mọi trang (tông xanh lá dịu + be) */
:root {
  --nen: #F6F1E7; --nen-dam: #EDE5D6; --the: #FFFDF8;
  --xanh: #5E8466; --xanh-dam: #3E5C46; --xanh-nhat: #DCE6D8;
  --chu: #2F3A32; --chu-nhat: #5F6A61; --vien: #E2D9C7;
  --do: #A4472C;
  --bong: 0 14px 40px rgba(62, 92, 70, 0.10);
  --serif: "Lora", Georgia, serif;
  --sans: "Be Vietnam Pro", "Segoe UI", Arial, sans-serif;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: var(--sans); background: var(--nen); color: var(--chu); line-height: 1.75; font-size: 16.5px; -webkit-font-smoothing: antialiased; overflow-x: hidden; min-height: 100vh; display: flex; flex-direction: column; }
main { flex: 1; }
a { color: var(--xanh-dam); }
.khung { max-width: 760px; margin: 0 auto; padding: 0 20px; }

/* Thanh trên */
header { position: sticky; top: 0; z-index: 10; background: rgba(246, 241, 231, 0.92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--vien); }
header .khung { display: flex; align-items: center; justify-content: space-between; height: 60px; max-width: 980px; }
.logo { font-family: var(--serif); font-size: 24px; font-weight: 600; color: var(--xanh-dam); text-decoration: none; display: flex; align-items: center; gap: 8px; }
.logo svg { width: 26px; height: 26px; }
.nut-khan { font-size: 14px; font-weight: 500; color: var(--do); text-decoration: none; border: 1.5px solid #E3B9A9; padding: 6px 14px; border-radius: 999px; background: #FBEDE6; }
.nut-khan:hover { background: #F6DDD1; }
.ve { display: inline-flex; align-items: center; gap: 6px; font-size: 14.5px; color: var(--chu-nhat); text-decoration: none; margin: 24px 0 8px; }
.ve:hover { color: var(--xanh-dam); }

/* Chữ */
h1 { font-family: var(--serif); font-weight: 600; font-size: clamp(32px, 8vw, 44px); color: var(--xanh-dam); line-height: 1.2; margin-bottom: 10px; }
h2 { font-family: var(--serif); font-weight: 600; font-size: clamp(24px, 5.5vw, 30px); color: var(--xanh-dam); margin-bottom: 10px; line-height: 1.3; }
.dan { color: var(--chu-nhat); margin-bottom: 26px; }
.trang { padding: 8px 0 64px; }

/* Nút */
.nut { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 13px 24px; border-radius: 999px; font: 500 15.5px var(--sans); text-decoration: none; cursor: pointer; border: 1.5px solid var(--xanh); transition: .2s; }
.nut-chinh { background: var(--xanh); color: #fff; }
.nut-chinh:hover { background: var(--xanh-dam); border-color: var(--xanh-dam); }
.nut-phu { background: transparent; color: var(--xanh-dam); }
.nut-phu:hover { background: var(--xanh-nhat); }
.nut:disabled { opacity: .6; cursor: wait; }

/* Biểu mẫu */
.the-mau { background: var(--the); border: 1px solid var(--vien); border-radius: 22px; padding: 28px 26px; box-shadow: var(--bong); }
@media (max-width: 420px) { .the-mau { padding: 22px 18px; } }
label { display: block; font-weight: 500; font-size: 15px; margin: 18px 0 6px; }
label:first-of-type { margin-top: 0; }
.tuy { font-weight: 400; color: var(--chu-nhat); font-size: 13.5px; }
input, textarea, select { width: 100%; font: 400 16px var(--sans); color: var(--chu); background: var(--nen); border: 1.5px solid var(--vien); border-radius: 12px; padding: 12px 14px; outline: none; transition: .2s; }
input:focus, textarea:focus, select:focus { border-color: var(--xanh); background: #fff; }
textarea { resize: vertical; min-height: 160px; line-height: 1.7; }
.hang-2 { display: grid; grid-template-columns: 140px 1fr; gap: 10px; }
@media (max-width: 480px) { .hang-2 { grid-template-columns: 1fr; } }
.ghi-chu { font-size: 13.5px; color: var(--chu-nhat); margin-top: 6px; line-height: 1.55; }
.bay { position: absolute; left: -9999px; width: 1px; height: 1px; overflow: hidden; }
.the-mau .nut { margin-top: 22px; width: 100%; }
.bao { display: none; margin-top: 16px; padding: 14px 16px; border-radius: 12px; font-size: 15px; }
.bao.ok { display: block; background: var(--xanh-nhat); color: var(--xanh-dam); }
.bao.loi { display: block; background: #F5E1DA; color: #8A3D27; }
.bao a { color: inherit; font-weight: 600; }
.dem { text-align: right; font-size: 12.5px; color: var(--chu-nhat); margin-top: 4px; }
.o-tick { display: flex; gap: 10px; align-items: flex-start; margin-top: 18px; padding: 14px; border-radius: 12px; background: var(--nen); border: 1px solid var(--vien); cursor: pointer; font-weight: 400; }
.o-tick input { width: 20px; height: 20px; flex: none; margin-top: 3px; accent-color: var(--xanh); }
.o-tick b { font-weight: 600; }

/* Nội quy */
.noi-quy { background: var(--xanh-nhat); border-radius: 16px; padding: 16px 18px; font-size: 14.5px; color: var(--xanh-dam); line-height: 1.65; }
.noi-quy strong { display: block; margin-bottom: 4px; }
.noi-quy ul { padding-left: 18px; }

/* Chân trang */
footer { padding: 36px 0 44px; text-align: center; font-size: 14px; color: var(--chu-nhat); border-top: 1px solid var(--vien); }
footer .logo { justify-content: center; font-size: 20px; margin-bottom: 6px; }
.cau-cuoi { font-family: var(--serif); font-style: italic; font-size: 16px; max-width: 420px; margin: 0 auto 14px; }
.lien-ket-chan { display: flex; flex-wrap: wrap; justify-content: center; gap: 6px 18px; font-size: 14px; }
.lien-ket-chan a { color: var(--chu-nhat); text-decoration: none; }
.lien-ket-chan a:hover { color: var(--xanh-dam); }
.lien-ket-chan a.khan { color: var(--do); font-weight: 500; }

@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }