/* ==========================================================================
   PORTFOLIO REDESIGN - "THE DEVELOPER'S DESK"
   ========================================================================== */

/* ==================== ROOT VARIABLES ==================== */
:root {
  /* Color Palette (Dark Theme) - Monochrome Professional */
  --bg-primary-dark: #121212;
  --bg-secondary-dark: #1E1E1E;
  --text-primary-dark: #E0E0E0;
  --text-secondary-dark: #A0A0A0;
  --accent-primary-dark: #FFFFFF;
  --accent-secondary-dark: #E0E0E0;
  --border-dark: #2C2C2C;

  /* Color Palette (Light Theme) - Monochrome Professional */
  --bg-primary-light: #FFFFFF;
  --bg-secondary-light: #F5F5F5;
  --text-primary-light: #212121;
  --text-secondary-light: #757575;
  --accent-primary-light: #000000;
  --accent-secondary-light: #212121;
  --border-light: #EEEEEE;

  /* Typography */
  --font-heading: 'Space Grotesk', sans-serif;
  --font-body: 'Space Grotesk', sans-serif;
  --font-mono: 'Fira Code', monospace;

  /* Sizing & Spacing */
  --sidebar-width: 280px;
  --mobile-header-height: 70px;
  --max-width: 1100px;
  --border-radius: 8px;
  --transition: all 0.3s ease-in-out;
}

/* ==================== THEME SETUP ==================== */
body {
  transition: background-color 0.3s ease, color 0.3s ease;
}

[data-theme="dark"] {
  --bg-primary: var(--bg-primary-dark);
  --bg-secondary: var(--bg-secondary-dark);
  --text-primary: var(--text-primary-dark);
  --text-secondary: var(--text-secondary-dark);
  --accent-primary: var(--accent-primary-dark);
  --accent-secondary: var(--accent-secondary-dark);
  --border-color: var(--border-dark);
}

[data-theme="light"] {
  --bg-primary: var(--bg-primary-light);
  --bg-secondary: var(--bg-secondary-light);
  --text-primary: var(--text-primary-light);
  --text-secondary: var(--text-secondary-light);
  --accent-primary: var(--accent-primary-light);
  --accent-secondary: var(--accent-secondary-light);
  --border-color: var(--border-light);
}

/* ==================== RESET & BASE ==================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 4rem; /* For section jumps */
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--accent-primary);
  text-decoration: none;
  transition: var(--transition);
}

a:hover {
  color: var(--accent-secondary);
}

/* ==================== ACCESSIBILITY ==================== */
.skip-link {
  position: absolute;
  top: -100px;
  left: 0;
  background: var(--accent-primary);
  color: white;
  padding: 1rem 1.5rem;
  z-index: 9999;
  transition: top 0.3s ease;
}

.skip-link:focus {
  top: 0;
}

/* ==================== LOADING OVERLAY ==================== */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--bg-primary-dark);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  transition: opacity 0.5s ease;
}

.loading-overlay.hidden {
  opacity: 0;
  pointer-events: none;
}

.loader-text {
  font-family: var(--font-mono);
  color: var(--accent-primary-dark);
  font-size: 1.2rem;
}

.loader-text::after {
  content: '_';
  animation: blink 1s step-end infinite;
}

@keyframes blink {
  50% { opacity: 0; }
}

/* ==================== LAYOUT ==================== */
.main-container {
  margin-left: var(--sidebar-width);
}

/* ==================== SIDEBAR NAVIGATION ==================== */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--bg-primary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  padding: 2rem;
  z-index: 1000;
  transition: transform 0.4s ease;
}

.sidebar-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 4rem;
}

.logo .logo-text {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
}

.theme-toggle {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1.25rem;
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 50%;
  transition: var(--transition);
}

.theme-toggle:hover {
  color: var(--accent-primary);
  background: var(--bg-secondary);
}

.nav-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.nav-link {
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 1rem;
  position: relative;
  padding: 0.5rem 0;
}

.nav-link span {
  color: var(--accent-primary);
}

.nav-link::before {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background: var(--accent-primary);
  transition: width 0.3s ease;
}

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

.nav-link.active::before {
  width: 100%;
}

.sidebar-footer {
  margin-top: auto;
}

.sidebar-footer .social-links {
  display: flex;
  gap: 1.5rem;
  justify-content: center;
  font-size: 1.5rem;
}

.sidebar-footer .social-links a {
  color: var(--text-secondary);
}
.sidebar-footer .social-links a:hover {
  color: var(--accent-primary);
  transform: translateY(-3px);
}

/* ==================== MOBILE HEADER & NAVIGATION ==================== */
.mobile-header {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--mobile-header-height);
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  padding: 0 1.5rem;
  justify-content: space-between;
  align-items: center;
  z-index: 1001;
}

.menu-toggle {
  background: none;
  border: none;
  cursor: pointer;
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1002;
}

.hamburger {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  position: relative;
  transition: background 0.2s ease;
}
.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  transition: transform 0.3s ease, top 0.3s ease;
}
.hamburger::before { top: -8px; }
.hamburger::after { top: 8px; }

.menu-toggle.active .hamburger {
  background: transparent;
}
.menu-toggle.active .hamburger::before {
  top: 0;
  transform: rotate(45deg);
}
.menu-toggle.active .hamburger::after {
  top: 0;
  transform: rotate(-45deg);
}


/* ==================== MAIN CONTENT & SECTIONS ==================== */
main {
  padding: 4rem 3rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.section {
  min-height: 80vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 6rem 0;
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.section.visible {
  opacity: 1;
  transform: translateY(0);
}


.section-title {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  margin-bottom: 3rem;
  position: relative;
  padding-left: 4.5rem;
}

.section-title::before {
  content: "0" attr(data-number) ".";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  color: var(--accent-primary);
  font-size: 1.5rem;
}


/* ==================== HOME/HERO SECTION ==================== */
#home {
  justify-content: center;
  min-height: 100vh;
}

.hero-intro {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--accent-primary);
  margin-bottom: 1rem;
}

.hero-title {
  font-family: var(--font-heading);
  font-size: clamp(3rem, 7vw, 5rem);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.hero-subtitle {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  font-weight: 500;
  line-height: 1.2;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  min-height: 80px; /* Reserve space for typing */
}

.hero-description {
  max-width: 600px;
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 3rem;
}

.hero-cta {
  font-size: 1.1rem;
}


/* ==================== ABOUT SECTION ==================== */
.about-grid {
  display: grid;
  grid-template-columns: 3fr 2fr;
  gap: 3rem;
  align-items: flex-start;
}

.about-text p {
  margin-bottom: 1.5rem;
  color: var(--text-secondary);
  font-size: 1.05rem;
}
.about-text .btn {
  margin-top: 2rem;
}

.about-image {
  position: relative;
}

.image-wrapper {
  position: relative;
  border-radius: var(--border-radius);
  background: var(--accent-primary);
  width: fit-content;
}

.image-wrapper::after {
  content: '';
  position: absolute;
  top: 15px;
  left: 15px;
  width: 100%;
  height: 100%;
  border: 2px solid var(--accent-primary);
  border-radius: var(--border-radius);
  z-index: -1;
  transition: var(--transition);
}
.image-wrapper:hover::after {
  top: 10px;
  left: 10px;
}

.profile-img {
  border-radius: var(--border-radius);
  position: relative;
  mix-blend-mode: multiply;
  filter: grayscale(100%) contrast(1.2);
  transition: var(--transition);
}

[data-theme="dark"] .profile-img {
  mix-blend-mode: screen;
}

.image-wrapper:hover .profile-img {
  mix-blend-mode: normal;
  filter: none;
}


/* ==================== SKILLS SECTION ==================== */
.skills-list {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.95rem;
}
.skill-item {
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  padding: 0.75rem 1.25rem;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  transition: var(--transition);
  cursor: default;
}

.skill-item:hover {
  color: var(--accent-primary);
  border-color: var(--accent-primary);
  transform: translateY(-3px);
  box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.skill-item span {
  color: var(--accent-primary);
  font-weight: 600;
}


/* ==================== PROJECTS SECTION ==================== */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
}

.project-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}
.project-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px -15px rgba(0,0,0,0.2);
  border-color: var(--accent-primary);
}

.project-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
}
.project-header > i {
  font-size: 2.5rem;
  color: var(--accent-primary);
}
.project-links {
  display: flex;
  gap: 1rem;
}
.project-links a {
  font-size: 1.25rem;
  color: var(--text-secondary);
}
.project-links a:hover {
  color: var(--accent-primary);
}

.project-title {
  font-family: var(--font-heading);
  font-size: 1.4rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.project-description {
  color: var(--text-secondary);
  font-size: 0.95rem;
  flex-grow: 1;
  margin-bottom: 1.5rem;
}

.project-footer .project-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-secondary);
}


/* ==================== EXPERIENCE SECTION ==================== */
.experience-container {
  display: flex;
  gap: 2rem;
}
.experience-tabs {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.tab-link {
  font-family: var(--font-mono);
  font-size: 0.95rem;
  background: none;
  border: none;
  border-left: 2px solid var(--border-color);
  color: var(--text-secondary);
  padding: 0.75rem 1.25rem;
  cursor: pointer;
  text-align: left;
  transition: var(--transition);
  position: relative;
}
.tab-link:hover {
  background: var(--bg-secondary);
  color: var(--accent-primary);
}
.tab-link.active {
  color: var(--accent-primary);
  border-left-color: var(--accent-primary);
}
.experience-content {
  flex-grow: 1;
}
.tab-panel {
  display: none;
}
.tab-panel.active {
  display: block;
}

.experience-title {
  font-size: 1.4rem;
  font-weight: 500;
  margin-bottom: 0.25rem;
}
.experience-company {
  color: var(--accent-primary);
}
.experience-duration {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
}
.experience-list {
  list-style: none;
}
.experience-list li {
  position: relative;
  padding-left: 1.5rem;
  margin-bottom: 0.75rem;
  color: var(--text-secondary);
}
.experience-list li::before {
  content: '▹';
  position: absolute;
  left: 0;
  color: var(--accent-primary);
}

/* ==================== CONTACT SECTION ==================== */
#contact {
  text-align: center;
}
.contact-content {
  max-width: 600px;
  margin: 0 auto;
}
.contact-content h3 {
  font-family: var(--font-heading);
  font-size: 2rem;
  margin-bottom: 1rem;
}
.contact-content p {
  color: var(--text-secondary);
  margin-bottom: 2rem;
  font-size: 1.1rem;
}


/* ==================== BUTTONS ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.8rem 1.75rem;
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 500;
  border: 1px solid var(--accent-primary);
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: var(--transition);
}
.btn-primary {
  background: var(--accent-primary);
  color: var(--bg-primary);
}
.btn-primary:hover {
  background: transparent;
  color: var(--accent-primary);
}
.btn-secondary {
  background: transparent;
  color: var(--accent-primary);
}
.btn-secondary:hover {
  background: var(--accent-primary);
  color: var(--bg-primary);
}


/* ==================== RESPONSIVE DESIGN ==================== */
@media (max-width: 1024px) {
  .about-grid {
    grid-template-columns: 1fr;
  }
  .about-image {
    margin: 0 auto;
    max-width: 350px;
  }
}

@media (max-width: 768px) {
  .main-container {
    margin-left: 0;
  }
  
  .sidebar {
    transform: translateX(-100%);
    box-shadow: 5px 0 25px rgba(0,0,0,0.3);
  }
  
  .sidebar.active {
    transform: translateX(0);
  }
  
  .mobile-header {
    display: flex;
  }

  body.menu-open {
    overflow: hidden;
  }

  main {
    padding: 2rem 1.5rem;
  }

  .section {
    padding: 4rem 0;
  }
  
  .section-title {
    padding-left: 0;
    text-align: center;
  }
  .section-title::before {
    display: none;
  }

  .experience-container {
    flex-direction: column;
  }
  .experience-tabs {
    flex-direction: row;
    overflow-x: auto;
    border-bottom: 1px solid var(--border-color);
  }
  .tab-link {
    border-left: none;
    border-bottom: 2px solid transparent;
    white-space: nowrap;
  }
  .tab-link.active {
    border-left: none;
    border-bottom-color: var(--accent-primary);
  }
}