:root {
  --brg-ultra-dark: #001F12; /* เขียวบริติชเข้มพิเศษ */
  --brg-dark: #002B18;       /* เขียวบริติชเข้มหลัก */
  --brg-main: #004225;       /* เขียวบริติชมาตรฐาน */
  --brg-light: #0D5C36;
  --gold-accent: #C5A059;   /* สีทอง */
  --gold-hover: #A3803C;
  --bg-cream: #F4F6F4;
  --card-bg: #FFFFFF;
  --text-main: #1A2820;
  --text-muted: #52635A;
  --border-color: #D2DDD7;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Sarabun', system-ui, sans-serif;
}

body {
  background-color: var(--bg-cream);
  color: var(--text-main);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ===================================================
   HEADER & NAVBAR (DARK BRITISH RACING GREEN)
   =================================================== */
header, .navbar {
  background: linear-gradient(135deg, var(--brg-ultra-dark), var(--brg-dark));
  color: #ffffff;
  padding: 1.25rem 2rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  border-bottom: 3px solid var(--gold-accent);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

header h1, .navbar .logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: #ffffff;
  text-decoration: none;
  letter-spacing: 0.5px;
}

/* เมนูเนวิเกชันแบบตัวหนังสือล้วน (ไม่มีกรอบกล่อง) */
nav ul, .nav-links {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  gap: 1.5rem;
  align-items: center;
  margin: 0;
  padding: 0;
}

nav a, .nav-links a {
  color: #E2ECE6 !important;
  text-decoration: none;
  font-weight: 500;
  padding: 0.3rem 0;
  background: transparent !important;
  border: none !important;
  transition: color 0.2s ease-in-out;
}

nav a:hover, .nav-links a:hover {
  color: var(--gold-accent) !important;
  background: transparent !important;
}

/* ===================================================
   MAIN CONTENT & LAYOUT STRUCTURE
   =================================================== */
main {
  max-width: 900px;
  width: 90%;
  margin: 2rem auto;
  flex: 1;
}

.page-layout {
  display: flex;
  gap: 2rem;
  max-width: 1100px;
  width: 90%;
  margin: 2rem auto;
  flex: 1;
}

.main-content {
  flex: 1;
}

/* Card & Grid */
section, .card {
  background-color: var(--card-bg);
  padding: 2rem;
  border-radius: 12px;
  border: 1px solid var(--border-color);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  margin-bottom: 1.5rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.card h3 {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.5rem;
  margin-bottom: 0.8rem;
  display: block;
}

.card .btn {
  display: inline-block;
  margin-top: 1rem;
  background-color: var(--brg-main);
  color: #ffffff;
  padding: 0.5rem 1rem;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  transition: background-color 0.2s;
}

.card .btn:hover {
  background-color: var(--brg-dark);
}

h2, h3 {
  color: var(--brg-main);
  margin-bottom: 1rem;
  border-bottom: 2px solid var(--gold-accent);
  padding-bottom: 0.3rem;
  display: inline-block;
}

aside {
  background-color: #EBF1EE;
  border-left: 4px solid var(--brg-main);
  padding: 1.25rem;
  margin: 1.5rem 0;
  border-radius: 0 8px 8px 0;
}

blockquote {
  font-style: italic;
  color: var(--brg-dark);
  font-weight: bold;
  margin-bottom: 0.5rem;
}

/* ===================================================
   FORM STYLING
   =================================================== */
form p, form fieldset {
  margin-bottom: 1.2rem;
}

label {
  font-weight: 600;
  color: var(--brg-dark);
  display: inline-block;
  margin-bottom: 0.3rem;
}

input[type="text"],
input[type="email"],
input[type="url"],
input[type="password"],
input[type="number"],
input[type="date"],
input[type="tel"],
select {
  width: 100%;
  padding: 0.6rem 0.8rem;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 1rem;
  background-color: #FAFDFC;
}

input:focus, select:focus {
  outline: none;
  border-color: var(--brg-light);
  box-shadow: 0 0 0 3px rgba(13, 92, 54, 0.15);
}

fieldset {
  border: 1px solid var(--border-color);
  padding: 1rem;
  border-radius: 8px;
}

legend {
  font-weight: bold;
  color: var(--brg-main);
  padding: 0 0.5rem;
}

button {
  background-color: var(--brg-main);
  color: #ffffff;
  border: none;
  padding: 0.7rem 1.5rem;
  font-size: 1rem;
  font-weight: bold;
  border-radius: 6px;
  cursor: pointer;
  transition: background-color 0.2s;
}

button:hover {
  background-color: var(--brg-dark);
}

button[type="reset"] {
  background-color: #6C757D;
}

button[type="reset"]:hover {
  background-color: #5A6268;
}

/* ===================================================
   DEFINITION LIST (RESULT PAGE)
   =================================================== */
dl {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 0.8rem 1rem;
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

dt {
  font-weight: bold;
  color: var(--brg-main);
}

dd {
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

/* ===================================================
   FOOTER
   =================================================== */
footer, .site-footer {
  background-color: var(--brg-ultra-dark);
  color: #A3B8AC;
  padding: 1.5rem;
  margin-top: auto;
  border-top: 3px solid var(--gold-accent);
}

.site-footer {
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  gap: 1.5rem;
  text-align: left;
}

.footer-section h4 {
  color: var(--gold-accent);
  margin-bottom: 0.5rem;
}

.footer-section a {
  color: #E2ECE6;
  text-decoration: none;
}

.footer-section a:hover {
  color: var(--gold-accent);
}

footer p {
  text-align: center;
  font-size: 0.9rem;
}