:root{
  --bg:#121212; 
  --card:#1E1E1E; 
  --muted:#9ca3af; 
  --text:#e5e7eb;
  --up:#16a34a; 
  --down:#dc2626;
  --border-color: rgba(255,255,255,0.04);
}
html,body{height:100%;margin:0;background:var(--bg);color:var(--text);font-family:Inter,system-ui,Arial;}
.wrap{max-width:1100px;margin:24px auto;padding:0 16px;}
.card{background:var(--card);border:1px solid rgba(255,255,255,0.03);border-radius:12px;padding:14px;box-shadow:0 8px 30px rgba(0,0,0,.45);}
.row{display:flex;gap:8px;align-items:center;flex-wrap:wrap;}
select,input,button{background:var(--bg);color:var(--text);border:1px solid var(--border-color);padding:8px 10px;border-radius:8px;}
button{cursor:pointer}
label{font-size:13px;color:var(--muted)}
#chart{height:520px;margin-top:12px;}
.info{font-size:13px;color:var(--muted);margin-top:8px;display:flex;justify-content:space-between;align-items:center;}
.small{font-size:12px;color:var(--muted)}
.rate-widget {
  display: flex;
  gap: 16px;
  margin-bottom: 16px;
}
.rate-box {
  background: var(--card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 16px;
  flex-grow: 1;
  text-align: center;
}
.rate-label {
  display: block;
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 8px;
}
.rate-value {
  display: block;
  font-size: 48px;
  font-weight: bold;
  color: var(--text);
}

/* --- Widget de Mejor Precio --- */
.rate-widget-card {
  margin-bottom: 16px;
  padding: 20px;
  position: relative;
  overflow: hidden;
}
.rate-widget-card::after {
  content: '';
  position: absolute;
  top: -20px;
  right: -30px;
  width: 150px;
  height: 150px;
  background-image: url('../img/usdt-logo.svg');
  background-size: contain;
  background-repeat: no-repeat;
  opacity: 0.05;
  z-index: 0;
}
.rate-widget-card > * {
  position: relative;
  z-index: 1;
}

.widget-title {
  text-align: center;
  font-size: 24px;
  margin-bottom: 16px;
  color: var(--text);
}
.rate-container {
  display: flex;
  justify-content: space-around;
  align-items: center;
}
.rate-separator {
  width: 1px;
  height: 60px;
  background-color: var(--border-color);
}
.widget-footer {
  text-align: center;
  font-size: 12px;
  color: var(--muted);
  margin-top: 16px;
}
.rate-widget-card .rate-box {
    border: none;
    padding: 0 16px;
}

/* --- Main Layout --- */
body {
  padding-top: 70px; /* Header height */
  padding-bottom: 60px; /* Footer height */
}

main.wrap {
  padding-top: 24px;
  padding-bottom: 24px;
}

.main-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 60px;
  background-color: var(--card);
  border-bottom: 1px solid var(--border-color);
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.wrap-header {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo {
  font-size: 20px;
  font-weight: bold;
  color: var(--text);
  text-decoration: none;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-links {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 20px;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 15px;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--text);
}

.theme-toggle-btn {
  background: none;
  border: none;
  color: var(--text);
  cursor: pointer;
  font-size: 20px;
  padding: 4px;
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text);
  cursor: pointer;
}

.main-footer {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  background-color: var(--bg);
  border-top: 1px solid var(--border-color);
  z-index: 1000;
  padding: 10px 0;
}

.footer-content {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}

.footer-logo {
  font-size: 14px;
  font-weight: bold;
  color: var(--muted);
}

.footer-disclaimer {
  font-size: 11px;
  color: var(--muted);
  text-align: right;
  margin: 0;
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .main-nav {
    position: absolute;
    top: 60px;
    left: 0;
    width: 100%;
    background-color: var(--card);
    border-bottom: 1px solid var(--border-color);
    flex-direction: column;
    align-items: stretch;
    padding: 10px 0;
    gap: 0;
    display: none; /* Hidden by default */
  }

  .main-nav.is-open {
    display: flex; /* Shown when toggled */
  }

  .nav-links {
    flex-direction: column;
    gap: 0;
  }

  .nav-links a {
    display: block;
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color);
  }
  
  .nav-links li:last-child a {
    border-bottom: none;
  }

  .main-nav .theme-toggle-btn {
    align-self: flex-start;
    margin: 10px 20px;
  }

  .mobile-menu-toggle {
    display: block;
  }
  
  .rate-container {
    flex-direction: column;
    gap: 16px;
  }
  .rate-separator {
    display: none;
  }

  .footer-content {
    flex-direction: column;
    gap: 8px;
  }
  .footer-disclaimer {
    text-align: center;
  }
}