/* ==========================================================================
   Speak.Hub.Landing Layout & Structural Styles
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 1.5rem);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  max-width: 100%;
}

body {
  font-family: var(--font-body);
  color: var(--text-main);
  background-color: var(--bg-app);
  line-height: 1.6;
  overflow-x: hidden;
  max-width: 100%;
  transition: background-color var(--transition-normal), color var(--transition-normal);
  position: relative;
}

/* Typography Base */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-main);
  letter-spacing: -0.02em;
}

p {
  color: var(--text-muted);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

img,
svg {
  display: block;
  max-width: 100%;
}

button,
input,
select,
textarea {
  font-family: inherit;
  font-size: inherit;
}

/* ==========================================================================
   Container & Grid System
   ========================================================================== */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
  position: relative;
  z-index: 1;
}

.section {
  padding: 6rem 0;
  position: relative;
  overflow: hidden;
}

.section-alt {
  background-color: var(--bg-surface-alt);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 4rem auto;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.9rem;
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-radius: var(--radius-pill);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
}

[data-theme="dark"] .section-tag {
  background: rgba(67, 97, 238, 0.15);
  color: hsl(var(--primary-h), 85%, 70%);
  border: 1px solid rgba(67, 97, 238, 0.3);
}

.section-title {
  font-size: clamp(2rem, 3.5vw, 2.75rem);
  margin-bottom: 1.25rem;
  color: var(--text-main);
}

.section-desc {
  font-size: 1.125rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* Grid Utilities */
.grid {
  display: grid;
  gap: 2rem;
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.header {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background-color: var(--bg-surface-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  z-index: var(--z-header);
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.35rem;
  color: var(--text-main);
}

.brand-logo-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  box-shadow: 0 4px 12px var(--color-primary-glow);
  font-size: 1.2rem;
}

.brand-logo-badge {
  font-size: 0.65rem;
  font-weight: 700;
  background: var(--color-accent);
  color: #032b24;
  padding: 0.15rem 0.4rem;
  border-radius: var(--radius-xs);
  text-transform: uppercase;
  margin-left: 0.25rem;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color var(--transition-fast);
  position: relative;
  padding: 0.5rem 0;
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  border-radius: var(--radius-pill);
  transition: width var(--transition-normal);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.nav-toggle-btn {
  display: none;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--text-main);
  font-size: 1.5rem;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  padding: 5rem 0 2rem 0;
  position: relative;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.8fr repeat(3, 1fr);
  gap: 3rem;
  margin-bottom: 4rem;
}

.footer-brand p {
  margin: 1rem 0 1.5rem 0;
  max-width: 320px;
  font-size: 0.95rem;
}

.footer-col-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 1.25rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.925rem;
  transition: color var(--transition-fast), transform var(--transition-fast);
  display: inline-block;
}

.footer-links a:hover {
  color: var(--color-primary);
  transform: translateX(3px);
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.875rem;
  color: var(--text-subtle);
}

.footer-socials {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  flex-wrap: wrap;
}

.footer-social-link {
  width: 40px;
  height: 40px;
  min-width: 40px;
  max-width: 40px;
  border-radius: var(--radius-md);
  background: var(--bg-surface-alt);
  border: 1px solid var(--border-subtle);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  text-decoration: none;
  transition: all var(--transition-fast);
  flex-shrink: 0;
  padding: 0;
}

.footer-social-link svg {
  width: 20px;
  height: 20px;
  transition: transform var(--transition-fast);
}

.footer-social-link:hover {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
  transform: translateY(-3px);
  box-shadow: 0 6px 16px var(--color-primary-glow);
}

.footer-social-link:hover svg {
  transform: scale(1.1);
}

.footer-social-link.social-facebook:hover {
  background: #1877f2;
  border-color: #1877f2;
  box-shadow: 0 6px 16px rgba(24, 119, 242, 0.4);
}

.footer-social-link.social-youtube:hover {
  background: #ff0000;
  border-color: #ff0000;
  box-shadow: 0 6px 16px rgba(255, 0, 0, 0.4);
}

.footer-social-link.social-zalo:hover {
  background: #0068ff;
  border-color: #0068ff;
  box-shadow: 0 6px 16px rgba(0, 104, 255, 0.4);
}

.footer-social-link.social-phone:hover {
  background: #10b981;
  border-color: #10b981;
  box-shadow: 0 6px 16px rgba(16, 185, 129, 0.4);
}

.footer-social-link.social-email:hover {
  background: #f59e0b;
  border-color: #f59e0b;
  box-shadow: 0 6px 16px rgba(245, 158, 11, 0.4);
}

/* ==========================================================================
   Custom Scrollbar & Top Scroll Progress Bar
   ========================================================================== */
.scroll-progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: var(--gradient-primary);
  box-shadow: 0 0 10px var(--color-primary-glow);
  z-index: calc(var(--z-header) + 50);
  transition: width 0.08s linear;
  pointer-events: none;
}

/* Webkit Scrollbar */
::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: var(--bg-app);
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, hsl(var(--primary-h), 65%, 45%), hsl(var(--secondary-h), 70%, 50%));
  border-radius: var(--radius-pill);
  border: 2px solid var(--bg-app);
  transition: background var(--transition-fast);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--gradient-primary);
  box-shadow: 0 0 12px var(--color-primary-glow);
}

/* Firefox scrollbar */
* {
  scrollbar-width: thin;
  scrollbar-color: hsl(var(--primary-h), 65%, 45%) var(--bg-app);
}