/* ==========================================
   GLOBAL THEME COLORS
   ========================================== */

:root {
  --bs-primary: #1e1780;
}

/* ==========================================
   NAVBAR
   ========================================== */

.navbar {
  background-color: #1e1780 !important;
}

.navbar-dark .navbar-nav .nav-link,
.navbar-brand {
  color: #ffffff !important;
  font-weight: 500;
}

.navbar-dark .navbar-nav .nav-link:hover,
.navbar-brand:hover {
  color: #e5e7eb !important;
}

/* ==========================================
   LINKS
   ========================================== */

a {
  color: #1e1780;
  text-decoration: none;
}

a:hover {
  color: #1e1780;
  text-decoration: underline;
}

/* ==========================================
   HEADINGS
   ========================================== */

h1,
h2,
h3 {
  color: #2c3e50;
  font-weight: 700;
  margin-top: 1.5em;
}

h4,
h5,
h6 {
  color: #34495e;
}

/* ==========================================
   LISTS
   ========================================== */

ul li {
  margin-bottom: 8px;
}

/* ==========================================
   TABLE OF CONTENTS (TOC)
   ========================================== */

#TOC-title {
  color: #1e1780;
  font-weight: 700;
}

#TOC a {
  color: #4b5563 !important;
}

#TOC a:hover {
  color: #1e1780 !important;
}

#TOC .active,
#TOC .nav-link.active,
.sidebar nav .active {
  color: #1e1780 !important;
  border-left: 3px solid #1e1780 !important;
  font-weight: 600;
}

/* ==========================================
   CODE BLOCKS
   ========================================== */

pre {
  border-radius: 8px;
}

code {
  color: #d63384;
}

/* ==========================================
   BUTTONS
   ========================================== */

.btn-primary {
  background-color: #1e1780;
  border-color: #1e1780;
}

.btn-primary:hover {
  background-color: #1e1780;
  border-color: #1e1780;
}

/* ==========================================
   FOOTER
   ========================================== */

footer {
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid #dee2e6;
  color: #6c757d;
  font-size: 0.9rem;
}

/* ==========================================
   CONTENT AREA
   ========================================== */

main {
  line-height: 1.7;
}

/* ==========================================
   SMOOTH SCROLL
   ========================================== */

html {
  scroll-behavior: smooth;
}

/* ==========================================
   MÀN HÌNH LOADING (PRELOADER) 
============================================= */
#preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: #0b0c10;
    z-index: 999999;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: opacity 0.6s ease, visibility 0.6s ease;
}

.loader-content {
    text-align: center;
}

.spinner {
    position: relative;
    width: 110px;
    height: 110px;
    margin: 0 auto;
    border-radius: 50%;
    background: conic-gradient(
        #00b894,
        #00d2d3,
        #ffb800,
        #ff2a4b,
        #00b894
    );
    mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    mask-composite: exclude;
    -webkit-mask-composite: xor;
    padding: 3px;
    box-shadow: 0 0 15px rgba(0, 210, 211, 0.25);
    animation: spin 1.4s cubic-bezier(0.42, 0, 0.58, 1) infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loader-text {
    color: #f3a683 !important;
    font-family: 'Courier New', Courier, monospace !important;
    letter-spacing: 5px !important;
    font-size: 16px !important;
    font-weight: bold;
    margin-bottom: 8px;
    text-transform: uppercase;
}

.loader-subtext {
    color: #57606f !important;
    font-size: 11px !important;
    letter-spacing: 3px !important;
    text-transform: uppercase;
}

#preloader.fade-out {
    opacity: 0;
    visibility: hidden;
}

.loader-center-group {
    position: relative;
    width: 110px;
    height: 110px;
    margin: 0 auto 35px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.loader-letter-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

.loader-letter {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    font-size: 36px;
    font-weight: 700;
    background: linear-gradient(135deg, #00cec9, #a55eea);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* ============================================================ */
/* ÉP CÁC CHỮ TRÊN NAVBAR NẰM TRÊN 1 DÒNG DUY NHẤT             */
/* ============================================================ */

.navbar-nav .nav-item .nav-link,
.navbar-nav .nav-item {
    white-space: nowrap !important;
}

.navbar-nav .nav-link {
    padding-left: 10px !important;
    padding-right: 10px !important;
    font-size: 0.95rem !important;
}

.navbar-collapse {
    flex-grow: 1;
    justify-content: flex-end;
}