/* ===== CSS Variables ===== */
:root {
  --red: #C74B3C;
  --red-dark: #8B1A1A;
  --red-light: #E85D4A;
  --gold: #D4A84B;
  --gold-light: #F0D080;
  --gold-dark: #B8860B;
  --ink: #2C1810;
  --ink-light: #5C4033;
  --paper: #FFF8F0;
  --paper-dark: #F5EDE0;
  --cream: #FAF0E6;
  --white: #FFFDF9;
  --shadow: rgba(139, 26, 26, 0.12);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
  background: var(--paper);
  color: var(--ink);
  min-height: 100vh;
  overflow-x: hidden;
}

/* Top Border */
.top-border {
  height: 4px;
  background: linear-gradient(90deg, var(--red-dark), var(--gold), var(--red), var(--gold), var(--red-dark));
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
}

/* Header */
header {
  position: fixed;
  top: 4px;
  left: 0;
  right: 0;
  z-index: 99;
  background: rgba(255, 248, 240, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(212, 168, 75, 0.25);
  height: 60px;
  transition: all 0.3s;
}
header.scrolled {
  box-shadow: 0 2px 20px var(--shadow);
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}
.logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--red), var(--red-dark));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gold-light);
  font-size: 20px;
  font-weight: bold;
  box-shadow: 0 2px 8px rgba(199, 75, 60, 0.3);
}
.logo-text {
  font-size: 24px;
  font-weight: 700;
  background: linear-gradient(135deg, var(--red-dark), var(--red));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: 4px;
}

nav.desktop {
  display: flex;
  gap: 6px;
}
nav a {
  text-decoration: none;
  color: var(--ink-light);
  font-size: 14px;
  padding: 6px 14px;
  border-radius: 6px;
  transition: all 0.2s;
  white-space: nowrap;
}
nav a:hover {
  background: rgba(199, 75, 60, 0.08);
  color: var(--red);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  color: var(--ink);
  cursor: pointer;
  padding: 4px;
}

/* Mobile Nav */
.mobile-nav {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 98;
  background: rgba(44, 24, 16, 0.95);
  backdrop-filter: blur(8px);
  padding: 80px 24px 40px;
  overflow-y: auto;
}
.mobile-nav.open { display: block; }
.mobile-nav a {
  display: block;
  padding: 14px 0;
  color: rgba(255,255,255,0.8);
  text-decoration: none;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  font-size: 16px;
  letter-spacing: 2px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.25s;
  cursor: pointer;
  border: none;
  white-space: nowrap;
}
.btn-primary {
  background: linear-gradient(135deg, var(--red), var(--red-dark));
  color: white;
  box-shadow: 0 4px 15px rgba(199, 75, 60, 0.3);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 25px rgba(199, 75, 60, 0.4);
}
.btn-secondary {
  border: 2px solid var(--gold);
  color: var(--gold-dark);
  background: transparent;
}
.btn-secondary:hover {
  background: rgba(212, 168, 75, 0.1);
  transform: translateY(-2px);
}
.btn-sm {
  padding: 8px 20px;
  font-size: 13px;
}

/* Page Header */
.page-header {
  padding: 100px 20px 40px;
  text-align: center;
  background: linear-gradient(180deg, rgba(199,75,60,0.06), transparent);
}
.page-header h1 {
  font-size: 32px;
  color: var(--red-dark);
  letter-spacing: 4px;
}
.page-header p {
  color: var(--ink-light);
  margin-top: 8px;
  font-size: 15px;
}

/* Section */
.section {
  padding: 60px 20px;
  max-width: 900px;
  margin: 0 auto;
}

/* Footer */
footer {
  background: var(--ink);
  color: rgba(255,255,255,0.6);
  padding: 48px 20px 32px;
  text-align: center;
}
footer .quote {
  color: var(--gold-light);
  font-size: 14px;
  line-height: 2;
  margin-bottom: 16px;
  opacity: 0.8;
}
footer .links {
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
  margin-bottom: 20px;
}
footer .links a {
  color: var(--gold);
  text-decoration: none;
  font-size: 13px;
  transition: opacity 0.2s;
}
footer .links a:hover { opacity: 0.7; }
footer .divider {
  width: 60px;
  height: 1px;
  background: rgba(212,168,75,0.3);
  margin: 20px auto;
}
footer .copyright {
  font-size: 12px;
  line-height: 1.8;
  color: rgba(255,255,255,0.4);
}

/* Card */
.card {
  background: var(--white);
  border: 1px solid rgba(212, 168, 75, 0.2);
  border-radius: 14px;
  padding: 28px;
  transition: all 0.3s;
  margin-bottom: 16px;
}
.card h3 {
  font-size: 20px;
  color: var(--ink);
  margin-bottom: 10px;
}
.card p, .card > div {
  font-size: 14px;
  color: var(--ink-light);
  line-height: 1.8;
}

/* Form elements */
input, textarea, select {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid rgba(212, 168, 75, 0.3);
  border-radius: 8px;
  font-size: 15px;
  background: var(--white);
  color: var(--ink);
  transition: border-color 0.2s;
  font-family: inherit;
}
input:focus, textarea:focus, select:focus {
  outline: none;
  border-color: var(--red);
  box-shadow: 0 0 0 3px rgba(199, 75, 60, 0.1);
}
label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink-light);
  margin-bottom: 6px;
}
.form-group {
  margin-bottom: 20px;
}

/* Alert / Result */
.alert {
  padding: 16px 20px;
  border-radius: 10px;
  margin-bottom: 16px;
  font-size: 14px;
  line-height: 1.7;
}
.alert-info {
  background: rgba(212, 168, 75, 0.1);
  border: 1px solid rgba(212, 168, 75, 0.3);
  color: var(--ink);
}
.alert-success {
  background: rgba(76, 175, 80, 0.08);
  border: 1px solid rgba(76, 175, 80, 0.25);
  color: #2E7D32;
}

/* Result box */
.result-box {
  background: var(--cream);
  border: 1px solid rgba(212, 168, 75, 0.2);
  border-radius: 14px;
  padding: 28px;
  margin-top: 24px;
  line-height: 1.9;
}
.result-box h3 {
  color: var(--red-dark);
  margin-bottom: 12px;
  font-size: 18px;
}
.result-box .label {
  font-weight: 600;
  color: var(--gold-dark);
}

/* Shake animation */
@keyframes shake {
  0%, 100% { transform: rotate(0deg); }
  20% { transform: rotate(-8deg); }
  40% { transform: rotate(8deg); }
  60% { transform: rotate(-6deg); }
  80% { transform: rotate(6deg); }
}
.shake {
  animation: shake 0.6s ease-in-out;
}

/* Fade in */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.6s ease-out;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Loading spinner */
.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2px solid rgba(199, 75, 60, 0.2);
  border-top-color: var(--red);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}
@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Tooltip */
.tooltip {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--ink);
  color: white;
  padding: 12px 24px;
  border-radius: 10px;
  font-size: 14px;
  z-index: 200;
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}
.tooltip.show { opacity: 1; }

/* Responsive */
@media (max-width: 768px) {
  nav.desktop { display: none; }
  .menu-toggle { display: block; }
  .page-header h1 { font-size: 26px; letter-spacing: 2px; }
}

/* Back link */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--ink-light);
  text-decoration: none;
  font-size: 14px;
  margin-bottom: 20px;
  transition: color 0.2s;
}
.back-link:hover { color: var(--red); }