/* --- Roadmap Header Polish --- */
/* SECTION CONTAINER */
.intro-section {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: var(--spacing-xxl) var(--spacing-lg);
  background: var(--bg-primary);
  color: var(--text-primary);
  position: relative;
  overflow: hidden;
  min-height: 90vh;
   padding-top: calc(var(--spacing-xxl) + 60px);
  transition: background 0.3s ease, color 0.3s ease;
}

.intro-section .container {
  display: flex;
  flex-wrap: wrap;
  max-width: 1200px;
  gap: var(--spacing-xxl);
  align-items: center;
}

/* LEFT SIDE */
.intro-left {
  flex: 1;
  min-width: 320px;
  animation: fadeInLeft 1s ease forwards;
}

.intro-left .section-title {
  font-size: 3rem;
  font-family: var(--font-heading);
  margin-bottom: var(--spacing-md);
  color: var(--accent-color);
  line-height: 1.2;
}

.intro-left .section-desc {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
}

/* STEPS LIST */
.steps-list {
  list-style: none;
  padding: 0;
  margin-bottom: var(--spacing-xl);
}

.step-item {
  display: flex;
  align-items: center;
  font-size: 1.125rem;
  margin-bottom: var(--spacing-md);
  padding: var(--spacing-md);
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 8px 20px rgba(0,0,0,0.08);
  transition: all 0.35s ease;
  cursor: default;
}

.step-item:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: 0 12px 30px rgba(0,170,255,0.2);
  border-left: 4px solid var(--accent-color);
}

.step-icon {
  font-size: 1.75rem;
  margin-right: var(--spacing-md);
}

/* RIGHT SIDE - ANIMATION CARD */
.intro-right {
  flex: 1;
  min-width: 320px;
  position: relative;
}

.animation-card {
  position: relative;
  width: 100%;
  max-width: 400px;
  height: 400px;
  margin: auto;
  perspective: 1000px;
}

/* FLOATING PYTHON LOGO */
.floating-img {
  width: 130px;
  animation: float 5s ease-in-out infinite;
  position: absolute;
  top: 40%;
  left: 40%;
  z-index: 10;
  transition: transform 0.3s ease;
}

.floating-img:hover {
  transform: rotateY(20deg) rotateX(10deg) scale(1.1);
}

/* FLOATING CIRCLES */
.floating-circle {
  position: absolute;
  border-radius: 50%;
  opacity: 0.25;
  animation: floatCircle 6s ease-in-out infinite;
}

.circle1 {
  width: 100px;
  height: 100px;
  background: var(--accent-color);
  top: 10%;
  left: 5%;
}

.circle2 {
  width: 60px;
  height: 60px;
  background: var(--accent-secondary);
  bottom: 10%;
  right: 10%;
}

.circle3 {
  width: 140px;
  height: 140px;
  background: var(--accent-color);
  top: 50%;
  right: 5%;
}

/* BUTTON */
.btn-primary {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-xl);
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  border-radius: var(--border-radius-lg);
  text-decoration: none;
  font-weight: bold;
  transition: all 0.35s ease;
  box-shadow: 0 6px 20px rgba(0,170,255,0.2);
}

.btn-primary:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 12px 30px rgba(0,170,255,0.4);
  background: linear-gradient(135deg, var(--accent-secondary), var(--accent-color));
}

/* ANIMATIONS */
@keyframes float {
  0%, 100% { transform: translateY(0px); }
  25% { transform: translateY(-15px) translateX(5px); }
  50% { transform: translateY(-25px) translateX(-5px); }
  75% { transform: translateY(-15px) translateX(5px); }
}

@keyframes floatCircle {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(45deg); }
}

@keyframes fadeInLeft {
  0% { opacity: 0; transform: translateX(-50px); }
  100% { opacity: 1; transform: translateX(0); }
}

/* RESPONSIVE */
@media (max-width: 1024px) {
  .intro-left .section-title { font-size: 2.5rem; }
  .intro-left .section-desc { font-size: 1.15rem; }
}

@media (max-width: 768px) {
  .intro-section .container { flex-direction: column; gap: var(--spacing-xl); }
  .intro-right { margin-top: var(--spacing-xl); }
}

/* SECTION CONTAINER */
.basics-section {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: var(--spacing-xxl) var(--spacing-lg);
  background: var(--bg-primary);
  color: var(--text-primary);
  position: relative;
  overflow: hidden;
  min-height: 90vh;
  transition: background 0.3s ease, color 0.3s ease;
}

.basics-section .container {
  display: flex;
  flex-wrap: wrap;
  max-width: 1200px;
  gap: var(--spacing-xxl);
  align-items: center;
}

/* LEFT SIDE */
.basics-left {
  flex: 1;
  min-width: 320px;
  animation: fadeInLeft 1s ease forwards;
}

.basics-left .section-title {
  font-size: 3rem;
  font-family: var(--font-heading);
  margin-bottom: var(--spacing-md);
  color: var(--accent-color);
  line-height: 1.2;
}

.basics-left .section-desc {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
}

/* BASICS LIST */
.basics-list {
  list-style: none;
  padding: 0;
  margin-bottom: var(--spacing-xl);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
}

.basics-item {
  display: flex;
  align-items: center;
  font-size: 1.125rem;
  padding: var(--spacing-md);
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 8px 20px rgba(0,0,0,0.08);
  transition: all 0.35s ease;
}

.basics-item:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: 0 12px 30px rgba(0,170,255,0.2);
  border-left: 4px solid var(--accent-color);
}

.item-icon {
  font-size: 1.5rem;
  margin-right: var(--spacing-md);
}

/* RIGHT SIDE - ANIMATION CARD */
.basics-right {
  flex: 1;
  min-width: 320px;
  position: relative;
}

.animation-card {
  position: relative;
  width: 100%;
  max-width: 400px;
  height: 400px;
  margin: auto;
  perspective: 1000px;
}

/* FLOATING PYTHON LOGO */
.floating-img {
  width: 130px;
  animation: float 5s ease-in-out infinite;
  position: absolute;
  top: 40%;
  left: 40%;
  z-index: 10;
  transition: transform 0.3s ease;
}

.floating-img:hover {
  transform: rotateY(20deg) rotateX(10deg) scale(1.1);
}

/* FLOATING CIRCLES */
.floating-circle {
  position: absolute;
  border-radius: 50%;
  opacity: 0.25;
  animation: floatCircle 6s ease-in-out infinite;
}

.circle1 {
  width: 100px;
  height: 100px;
  background: var(--accent-color);
  top: 10%;
  left: 5%;
}

.circle2 {
  width: 60px;
  height: 60px;
  background: var(--accent-secondary);
  bottom: 10%;
  right: 10%;
}

.circle3 {
  width: 140px;
  height: 140px;
  background: var(--accent-color);
  top: 50%;
  right: 5%;
}

/* BUTTON */
.btn-primary {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-xl);
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  border-radius: var(--border-radius-lg);
  text-decoration: none;
  font-weight: bold;
  transition: all 0.35s ease;
  box-shadow: 0 6px 20px rgba(0,170,255,0.2);
}

.btn-primary:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 12px 30px rgba(0,170,255,0.4);
  background: linear-gradient(135deg, var(--accent-secondary), var(--accent-color));
}

/* ANIMATIONS */
@keyframes float {
  0%, 100% { transform: translateY(0px); }
  25% { transform: translateY(-15px) translateX(5px); }
  50% { transform: translateY(-25px) translateX(-5px); }
  75% { transform: translateY(-15px) translateX(5px); }
}

@keyframes floatCircle {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(45deg); }
}

@keyframes fadeInLeft {
  0% { opacity: 0; transform: translateX(-50px); }
  100% { opacity: 1; transform: translateX(0); }
}

/* RESPONSIVE */
@media (max-width: 1024px) {
  .basics-left .section-title { font-size: 2.5rem; }
  .basics-left .section-desc { font-size: 1.15rem; }
  .basics-list { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .basics-section .container { flex-direction: column; gap: var(--spacing-xl); }
  .basics-right { margin-top: var(--spacing-xl); }
}

/* GETTING STARTED SECTION */
.getting-started-section {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: var(--spacing-xxl) var(--spacing-lg);
  background: var(--bg-primary);
  color: var(--text-primary);
  position: relative;
  overflow: hidden;
  min-height: 90vh;
  transition: background 0.3s ease, color 0.3s ease;
}

.getting-started-section .container {
  display: flex;
  flex-wrap: wrap;
  max-width: 1200px;
  gap: var(--spacing-xxl);
  align-items: center;
}

/* LEFT CONTENT */
.gs-left {
  flex: 1;
  min-width: 320px;
  animation: fadeInLeft 1s ease forwards;
}

.gs-left .section-title {
  font-size: 3rem;
  font-family: var(--font-heading);
  margin-bottom: var(--spacing-md);
  color: var(--accent-color);
}

.gs-left .section-desc {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
}

/* GETTING STARTED LIST */
.gs-list {
  list-style: none;
  padding: 0;
  margin-bottom: var(--spacing-xl);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
}

.gs-item {
  display: flex;
  align-items: center;
  font-size: 1.125rem;
  padding: var(--spacing-md);
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 8px 20px rgba(0,0,0,0.08);
  transition: all 0.35s ease;
}

.gs-item:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: 0 12px 30px rgba(0,170,255,0.2);
  border-left: 4px solid var(--accent-color);
}

.gs-item .item-icon {
  font-size: 1.5rem;
  margin-right: var(--spacing-md);
}

/* RIGHT ANIMATION CARD */
.gs-right {
  flex: 1;
  min-width: 320px;
  position: relative;
}

.gs-right .animation-card {
  position: relative;
  width: 100%;
  max-width: 400px;
  height: 400px;
  margin: auto;
  perspective: 1000px;
}

.gs-right .floating-img {
  width: 130px;
  animation: float 5s ease-in-out infinite;
  position: absolute;
  top: 40%;
  left: 40%;
  z-index: 10;
  transition: transform 0.3s ease;
}

.gs-right .floating-img:hover {
  transform: rotateY(20deg) rotateX(10deg) scale(1.1);
}

.floating-circle {
  position: absolute;
  border-radius: 50%;
  opacity: 0.25;
  animation: floatCircle 6s ease-in-out infinite;
}

.circle1 { width: 100px; height: 100px; background: var(--accent-color); top: 10%; left: 5%; }
.circle2 { width: 60px; height: 60px; background: var(--accent-secondary); bottom: 10%; right: 10%; }
.circle3 { width: 140px; height: 140px; background: var(--accent-color); top: 50%; right: 5%; }

/* BUTTON */
.btn-primary {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-xl);
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  border-radius: var(--border-radius-lg);
  text-decoration: none;
  font-weight: bold;
  transition: all 0.35s ease;
  box-shadow: 0 6px 20px rgba(0,170,255,0.2);
}

.btn-primary:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 12px 30px rgba(0,170,255,0.4);
  background: linear-gradient(135deg, var(--accent-secondary), var(--accent-color));
}

/* ANIMATIONS */
@keyframes float {
  0%, 100% { transform: translateY(0px); }
  25% { transform: translateY(-15px) translateX(5px); }
  50% { transform: translateY(-25px) translateX(-5px); }
  75% { transform: translateY(-15px) translateX(5px); }
}

@keyframes floatCircle {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(45deg); }
}

@keyframes fadeInLeft {
  0% { opacity: 0; transform: translateX(-50px); }
  100% { opacity: 1; transform: translateX(0); }
}

/* RESPONSIVE */
@media (max-width: 1024px) {
  .gs-left .section-title { font-size: 2.5rem; }
  .gs-left .section-desc { font-size: 1.15rem; }
  .gs-list { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .getting-started-section .container { flex-direction: column; gap: var(--spacing-xl); }
  .gs-right { margin-top: var(--spacing-xl); }
}

/* DATA STRUCTURES SECTION */
.data-structures-section {
  background: var(--bg-secondary);
  color: var(--text-primary);
  padding: var(--spacing-xxl) var(--spacing-lg);
  text-align: center;
  position: relative;
  overflow: hidden;
  transition: background 0.3s ease, color 0.3s ease;
}

.ds-header .section-title {
  font-size: 3rem;
  font-family: var(--font-heading);
  color: var(--accent-color);
  margin-bottom: var(--spacing-md);
  animation: fadeInUp 1s ease forwards;
}

.ds-header .section-desc {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xxl);
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
  animation: fadeInUp 1s ease 0.2s forwards;
}

/* CARDS CONTAINER */
.ds-cards-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-xl);
  max-width: 1200px;
  margin: 0 auto var(--spacing-xxl);
}

/* INDIVIDUAL CARD */
.ds-card {
  background: var(--card-bg);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow);
  transition: all 0.35s ease;
  position: relative;
  overflow: hidden;
  cursor: pointer;
}

.ds-card:hover {
  transform: translateY(-8px) scale(1.03);
  box-shadow: var(--shadow-hover-strong);
}

.ds-card-icon {
  font-size: 3rem;
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  width: 80px;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  margin: 0 auto var(--spacing-md);
  animation: float 4s ease-in-out infinite;
}

.ds-card h3 {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-sm);
  color: var(--accent-color);
}

.ds-card p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* BUTTON */
.btn-primary {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-xl);
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  border-radius: var(--border-radius-lg);
  text-decoration: none;
  font-weight: bold;
  transition: all 0.35s ease;
  box-shadow: 0 6px 20px rgba(0,170,255,0.2);
}

.btn-primary:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 12px 30px rgba(0,170,255,0.4);
  background: linear-gradient(135deg, var(--accent-secondary), var(--accent-color));
}

/* ANIMATIONS */
@keyframes float {
  0%, 100% { transform: translateY(0px); }
  25% { transform: translateY(-10px); }
  50% { transform: translateY(-15px); }
  75% { transform: translateY(-10px); }
}

@keyframes fadeInUp {
  0% { opacity: 0; transform: translateY(50px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* RESPONSIVE */
@media (max-width: 768px) {
  .ds-header .section-title { font-size: 2.5rem; }
  .ds-header .section-desc { font-size: 1.15rem; }
  .ds-cards-container { gap: var(--spacing-lg); }
}

/* FUNCTIONS & MODULES SECTION */
.functions-modules-section {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: var(--spacing-xxl) var(--spacing-lg);
  background: var(--bg-secondary);
  color: var(--text-primary);
  position: relative;
  overflow: hidden;
  min-height: 90vh;
  transition: background 0.3s ease, color 0.3s ease;
}

.functions-modules-section .container {
  display: flex;
  flex-wrap: wrap;
  max-width: 1200px;
  gap: var(--spacing-xxl);
  align-items: center;
}

/* LEFT CONTENT */
.fm-left {
  flex: 1;
  min-width: 320px;
  animation: fadeInLeft 1s ease forwards;
}

.fm-left .section-title {
  font-size: 3rem;
  font-family: var(--font-heading);
  margin-bottom: var(--spacing-md);
  color: var(--accent-color);
}

.fm-left .section-desc {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
}

/* LIST ITEMS */
.fm-list {
  list-style: none;
  padding: 0;
  margin-bottom: var(--spacing-xl);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
}

.fm-item {
  display: flex;
  align-items: center;
  font-size: 1.125rem;
  padding: var(--spacing-md);
  background: var(--bg-primary);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 8px 20px rgba(0,0,0,0.08);
  transition: all 0.35s ease;
}

.fm-item:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: 0 12px 30px rgba(0,170,255,0.2);
  border-left: 4px solid var(--accent-color);
}

.fm-item .item-icon {
  font-size: 1.5rem;
  margin-right: var(--spacing-md);
}

/* RIGHT ANIMATION CARD */
.fm-right {
  flex: 1;
  min-width: 320px;
  position: relative;
}

.fm-right .animation-card {
  position: relative;
  width: 100%;
  max-width: 400px;
  height: 400px;
  margin: auto;
  perspective: 1000px;
}

.fm-right .floating-img {
  width: 130px;
  animation: float 5s ease-in-out infinite;
  position: absolute;
  top: 40%;
  left: 40%;
  z-index: 10;
  transition: transform 0.3s ease;
}

.fm-right .floating-img:hover {
  transform: rotateY(20deg) rotateX(10deg) scale(1.1);
}

.floating-circle {
  position: absolute;
  border-radius: 50%;
  opacity: 0.25;
  animation: floatCircle 6s ease-in-out infinite;
}

.circle1 { width: 100px; height: 100px; background: var(--accent-color); top: 10%; left: 5%; }
.circle2 { width: 60px; height: 60px; background: var(--accent-secondary); bottom: 10%; right: 10%; }
.circle3 { width: 140px; height: 140px; background: var(--accent-color); top: 50%; right: 5%; }
.circle4 { width: 80px; height: 80px; background: var(--accent-secondary); top: 30%; left: 70%; }

/* BUTTON */
.btn-primary {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-xl);
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  border-radius: var(--border-radius-lg);
  text-decoration: none;
  font-weight: bold;
  transition: all 0.35s ease;
  box-shadow: 0 6px 20px rgba(0,170,255,0.2);
}

.btn-primary:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 12px 30px rgba(0,170,255,0.4);
  background: linear-gradient(135deg, var(--accent-secondary), var(--accent-color));
}

/* ANIMATIONS */
@keyframes float {
  0%, 100% { transform: translateY(0px); }
  25% { transform: translateY(-15px) translateX(5px); }
  50% { transform: translateY(-25px) translateX(-5px); }
  75% { transform: translateY(-15px) translateX(5px); }
}

@keyframes floatCircle {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(45deg); }
}

@keyframes fadeInLeft {
  0% { opacity: 0; transform: translateX(-50px); }
  100% { opacity: 1; transform: translateX(0); }
}

/* RESPONSIVE */
@media (max-width: 1024px) {
  .fm-left .section-title { font-size: 2.5rem; }
  .fm-left .section-desc { font-size: 1.15rem; }
  .fm-list { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .functions-modules-section .container { flex-direction: column; gap: var(--spacing-xl); }
  .fm-right { margin-top: var(--spacing-xl); }
}
/* OOP SECTION */
.oop-section {
  background: var(--bg-secondary);
  color: var(--text-primary);
  padding: var(--spacing-xxl) var(--spacing-lg);
  transition: background 0.3s ease, color 0.3s ease;
}

.oop-header .section-title {
  font-size: 3rem;
  color: var(--accent-color);
  text-align: center;
  margin-bottom: var(--spacing-md);
  animation: fadeInUp 1s ease forwards;
}

.oop-header .section-desc {
  text-align: center;
  max-width: 700px;
  margin: 0 auto var(--spacing-xxl);
  color: var(--text-secondary);
  font-size: 1.25rem;
  animation: fadeInUp 1s ease 0.2s forwards;
}

/* CARD GRID */
.oop-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--spacing-xl);
  max-width: 1000px;
  margin: 0 auto;
}

.oop-card {
  perspective: 1000px;
}

.card-front, .card-back {
  background: var(--card-bg);
  color: var(--text-primary);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow);
  min-height: 220px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  transition: transform 0.6s ease, box-shadow 0.3s ease;
  backface-visibility: hidden;
}

.card-front {
  cursor: pointer;
}

.oop-card:hover .card-front {
  transform: rotateY(180deg);
}

.card-back {
  position: absolute;
  top: 0;
  left: 0;
  transform: rotateY(180deg);
}

.oop-card:hover .card-back {
  transform: rotateY(0deg);
}

.card-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: #fff;
  width: 70px;
  height: 70px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  animation: float 4s ease-in-out infinite;
}

.card-back p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ANIMATIONS */
@keyframes fadeInUp {
  0% { opacity: 0; transform: translateY(50px); }
  100% { opacity: 1; transform: translateY(0); }
}

@keyframes float {
  0%,100%{transform:translateY(0px);}
  25%{transform:translateY(-8px);}
  50%{transform:translateY(-12px);}
  75%{transform:translateY(-8px);}
}

/* RESPONSIVE */
@media (max-width: 768px) {
  .oop-header .section-title { font-size: 2.5rem; }
  .oop-header .section-desc { font-size: 1.15rem; }
  .card-front, .card-back { min-height: 200px; padding: var(--spacing-md); }
  .card-icon { width: 60px; height: 60px; font-size: 2.5rem; }
}
/* FILE HANDLING SECTION */
.file-section {
  background: var(--bg-primary);
  color: var(--text-primary);
  padding: var(--spacing-xxl) var(--spacing-lg);
  position: relative;
  transition: background 0.3s ease, color 0.3s ease;
}

.file-header .section-title {
  font-size: 3rem;
  color: var(--accent-color);
  margin-bottom: var(--spacing-md);
  text-align: center;
  animation: fadeInUp 1s ease forwards;
}

.file-header .section-desc {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto var(--spacing-xxl);
  text-align: center;
  animation: fadeInUp 1s ease 0.2s forwards;
}

/* TIMELINE */
.file-timeline {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
  position: relative;
  max-width: 900px;
  margin: 0 auto var(--spacing-xxl);
}

.file-step {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-md);
  background: var(--card-bg);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
  position: relative;
  transition: transform 0.35s ease, box-shadow 0.35s ease;
}

.file-step:hover {
  transform: translateY(-5px) scale(1.02);
  box-shadow: var(--shadow-hover-strong);
}

.step-icon {
  font-size: 2.5rem;
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  flex-shrink: 0;
  animation: float 4s ease-in-out infinite;
}

.step-content h3 {
  font-size: 1.5rem;
  color: var(--accent-color);
  margin-bottom: var(--spacing-sm);
}

.step-content p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* BUTTON */
.file-section .btn-primary {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-xl);
  background: linear-gradient(135deg, var(--accent-color), var(--accent-secondary));
  color: white;
  border-radius: var(--border-radius-lg);
  text-decoration: none;
  font-weight: bold;
  transition: all 0.35s ease;
  box-shadow: 0 6px 20px rgba(0,170,255,0.2);
  text-align: center;
  margin-top: var(--spacing-xl);
}

.file-section .btn-primary:hover {
  transform: translateY(-5px) scale(1.05);
  box-shadow: 0 12px 30px rgba(0,170,255,0.4);
  background: linear-gradient(135deg, var(--accent-secondary), var(--accent-color));
}

/* ANIMATIONS */
@keyframes float {
  0%, 100% { transform: translateY(0px); }
  25% { transform: translateY(-8px); }
  50% { transform: translateY(-12px); }
  75% { transform: translateY(-8px); }
}

@keyframes fadeInUp {
  0% { opacity: 0; transform: translateY(50px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* RESPONSIVE */
@media (max-width: 768px) {
  .file-header .section-title { font-size: 2.5rem; }
  .file-header .section-desc { font-size: 1.15rem; }
  .file-step {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }
  .step-icon { margin-bottom: var(--spacing-sm); }
}
/* ADVANCED SECTION */
.advanced-section {
  background: var(--bg-primary);
  color: var(--text-primary);
  padding: var(--spacing-xxl) var(--spacing-lg);
  transition: background 0.3s ease, color 0.3s ease;
}

.advanced-header .section-title {
  font-size: 3rem;
  color: var(--accent-color);
  text-align: center;
  margin-bottom: var(--spacing-md);
  animation: fadeInUp 1s ease forwards;
}

.advanced-header .section-desc {
  text-align: center;
  max-width: 800px;
  margin: 0 auto var(--spacing-xxl);
  color: var(--text-secondary);
  font-size: 1.25rem;
  animation: fadeInUp 1s ease 0.2s forwards;
}

/* BUBBLE GRID */
.advanced-bubbles {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--spacing-lg);
}

.bubble {
  background: var(--card-bg);
  color: var(--text-primary);
  border-radius: 50%;
  width: 140px;
  height: 140px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--spacing-md);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.4s ease;
  position: relative;
  box-shadow: var(--shadow);
}

.bubble span {
  display: block;
  transition: transform 0.3s ease;
}

.bubble::after {
  content: attr(data-title);
  position: absolute;
  width: 220px;
  background: var(--accent-color);
  color: #fff;
  font-size: 0.9rem;
  padding: var(--spacing-sm);
  border-radius: var(--border-radius-md);
  text-align: center;
  opacity: 0;
  transform: translateY(-10px);
  pointer-events: none;
  transition: opacity 0.3s ease, transform 0.3s ease;
  z-index: 10;
}

.bubble:hover {
  transform: scale(1.25);
  box-shadow: var(--shadow-hover);
}

.bubble:hover::after {
  opacity: 1;
  transform: translateY(-50px);
}

/* ANIMATIONS */
@keyframes fadeInUp {
  0% { opacity: 0; transform: translateY(50px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* RESPONSIVE */
@media (max-width: 768px) {
  .bubble {
    width: 110px;
    height: 110px;
    font-size: 0.9rem;
  }

  .bubble::after {
    width: 180px;
    font-size: 0.8rem;
  }
  .step-icon { margin-bottom: var(--spacing-sm); }
}
/* OOP SECTION */
.oop-section {
  background: var(--bg-secondary);
  color: var(--text-primary);
  padding: var(--spacing-xxl) var(--spacing-lg);
  transition: background 0.3s ease, color 0.3s ease;
}

.oop-header .section-title {
  font-size: 3rem;
  color: var(--accent-color);
  text-align: center;
  margin-bottom: var(--spacing-md);
  animation: fadeInUp 1s ease forwards;
}
/* PROJECTS SECTION - ENHANCED */
.projects-section {
  background: var(--bg-primary);
  color: var(--text-primary);
  padding: var(--spacing-xxl) var(--spacing-lg);
  position: relative;
  overflow: hidden;
  transition: background 0.3s ease, color 0.3s ease;
}

.projects-header .section-title {
  font-size: 3.2rem;
  color: var(--accent-color);
  text-align: center;
  margin-bottom: var(--spacing-md);
  animation: fadeInUp 1s ease forwards;
  letter-spacing: 1px;
}

.projects-header .section-desc {
  text-align: center;
  max-width: 850px;
  margin: 0 auto var(--spacing-xxl);
  color: var(--text-secondary);
  font-size: 1.25rem;
  animation: fadeInUp 1s ease 0.2s forwards;
  line-height: 1.6;
}

/* PROJECT CARDS - HORIZONTAL */
.projects-cards {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xl);
  flex-wrap: wrap;
  margin-bottom: var(--spacing-xxl);
}

.project-card {
  background: linear-gradient(145deg, var(--accent-color), #00ffaa);
  color: white;
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-xl);
  width: 280px;
  box-shadow: 0 8px 25px rgba(0,0,0,0.15);
  transform: translateY(50px);
  opacity: 0;
  animation: fadeInUp 0.8s forwards;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.project-card:nth-child(1) { animation-delay: 0.2s; }
.project-card:nth-child(2) { animation-delay: 0.4s; }
.project-card:nth-child(3) { animation-delay: 0.6s; }

.project-card:hover {
  transform: translateY(-10px) scale(1.03);
  box-shadow: 0 12px 35px rgba(0,0,0,0.25);
}

.project-card h3 {
  font-size: 1.7rem;
  margin-bottom: var(--spacing-sm);
}

.project-card ul {
  list-style: disc;
  margin-left: var(--spacing-md);
  font-size: 1rem;
}

/* BEST PRACTICES CARDS */
.best-practices {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

.practice-card {
  background: var(--card-bg);
  color: var(--text-primary);
  padding: var(--spacing-md) var(--spacing-xl);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow);
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.4s ease, box-shadow 0.4s ease, background 0.3s ease;
}

.practice-card:hover {
  transform: translateY(-8px) scale(1.05);
  box-shadow: var(--shadow-hover-strong);
  background: var(--accent-color);
  color: #fff;
}

/* DECORATIVE GRADIENT SHAPE */
.gradient-shape {
  position: absolute;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(0,170,255,0.2), transparent 70%);
  border-radius: 50%;
  top: -150px;
  right: -150px;
  z-index: 0;
  pointer-events: none;
}

/* ANIMATIONS */
@keyframes fadeInUp {
  0% { opacity: 0; transform: translateY(50px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* RESPONSIVE */
@media (max-width: 1024px) {
  .projects-cards { gap: var(--spacing-lg); }
}

@media (max-width: 768px) {
  .projects-cards { flex-direction: column; align-items: center; }
  .gradient-shape { width: 300px; height: 300px; top: -100px; right: -100px; }
}

[data-theme='dark'] {
  .project-card {
    background: linear-gradient(145deg, #00aaff, #0aff9d);
    color: #fff;
  }
}