/* ===== ROOT VARIABLES ===== */
:root {
  /* Warm Dark Color Palette */
  --bg-primary: #1a1410;
  --bg-secondary: #2a2218;
  --bg-tertiary: #3a3228;
  --text-primary: #f5f1ed;
  --text-secondary: #d4ccc4;
  --text-tertiary: #a89f96;
  --accent-warm: #d4a574;
  --accent-warm-light: #e8c4a0;
  --accent-warm-dark: #b8845c;
  --border-color: #3a3228;
  --shadow-color: rgba(0, 0, 0, 0.3);

  /* Typography */
  --font-family: "Inter", -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  --h1: 700 3rem/1.2em var(--font-family);
  --h2: 600 2.25rem/1.2em var(--font-family);
  --h3: 600 1.5rem/1.2em var(--font-family);
  --h4: 500 1.25rem/1.6em var(--font-family);
  --font-size-large: 400 1rem/1.6em var(--font-family);
  --font-size-medium: 400 0.95rem/1.6em var(--font-family);
  --font-size-small: 400 0.875rem/1.8em var(--font-family);

  /* Spacing */
  --margin-xs: 0.5rem;
  --margin-s: 0.75rem;
  --margin-m: 1rem;
  --margin-l: 1.25rem;
  --margin-xl: 1.75rem;
  --margin-xxl: 2.5rem;
  --padding-xs: 0.5rem;
  --padding-s: 0.75rem;
  --padding-m: 1rem;
  --padding-l: 1.25rem;
  --padding-xl: 1.75rem;
  --padding-xxl: 2.5rem;

  /* Effects */
  --border-radius: 10px;
  --shadow-sm: 0 2px 8px var(--shadow-color);
  --shadow-md: 0 4px 16px var(--shadow-color);
  --shadow-lg: 0 8px 24px var(--shadow-color);
  --transition: all 0.3s ease;
}

/* ===== GLOBAL STYLES ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-family);
  font-size: 1rem;
  line-height: 1.6;
  font-weight: 400;
}

/* ===== TYPOGRAPHY ===== */
h1 {
  font: var(--h1);
  letter-spacing: -0.05em;
  color: var(--text-primary);
}

h2 {
  font: var(--h2);
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: var(--margin-l);
  margin-top: var(--margin-xl);
}

h3 {
  font: var(--h3);
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

h4 {
  font: var(--h4);
  color: var(--text-primary);
}

p {
  color: var(--text-secondary);
  line-height: 1.7;
}

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

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

code {
  font-family: "Courier New", "Courier", monospace;
  font-size: 0.9em;
  background-color: var(--bg-tertiary);
  padding: 2px 6px;
  border-radius: 4px;
  color: var(--accent-warm-light);
}

hr {
  border: none;
  height: 1px;
  background-color: var(--border-color);
  margin: var(--margin-xxl) 0;
}

/* ===== LAYOUT ===== */
.center-container {
  max-width: 768px;
  margin: 0 auto;
  padding: var(--padding-m);
}

/* ===== HEADER ===== */
header {
  text-align: center;
  margin-bottom: var(--margin-xxl);
  padding-top: var(--margin-xl);
}

.title {
  color: var(--text-primary);
  margin-bottom: var(--margin-m);
}

header > p {
  font-size: 1.125rem;
  margin-bottom: var(--margin-l);
  color: var(--text-secondary);
}

header > p span {
  color: var(--text-tertiary);
  font-size: 0.95rem;
}

/* ===== NAVIGATION / CONNECT ===== */
.mode-area {
  position: fixed;
  top: var(--margin-m);
  right: var(--margin-m);
  display: flex;
  gap: 0.5rem;
  z-index: 100;
}

.mode {
  padding: 0.5rem 0.75rem;
  font-size: 1rem;
  border: 2px solid var(--border-color);
  border-radius: 8px;
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  cursor: pointer;
  transition: var(--transition);
}

.mode:hover {
  border-color: var(--accent-warm);
  background-color: var(--bg-tertiary);
  transform: translateY(-2px);
}

.mode.active {
  background-color: var(--accent-warm);
  border-color: var(--accent-warm);
  color: var(--bg-primary);
}

.connect {
  display: flex;
  justify-content: center;
  gap: var(--margin-l);
  margin-top: var(--margin-l);
  flex-wrap: wrap;
}

.connect a {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-secondary);
  font-size: 1rem;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  transition: var(--transition);
}

.connect a:hover {
  color: var(--accent-warm-light);
  background-color: var(--bg-secondary);
  transform: translateY(-2px);
}

.connect svg {
  width: 20px;
  height: 20px;
  stroke: currentColor;
  fill: currentColor;
}

/* ===== MAIN CONTENT ===== */
main {
  margin-bottom: var(--margin-xxl);
}

.content h2:first-child {
  margin-top: 0;
}

/* ===== JOB / SECTION CARDS ===== */
.job {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: var(--padding-l);
  margin-bottom: var(--margin-l);
  transition: var(--transition);
}

.job:hover {
  background-color: var(--bg-tertiary);
  border-color: var(--accent-warm);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.job h3 {
  margin-bottom: var(--margin-s);
  color: var(--text-primary);
}

.job p {
  margin-bottom: var(--margin-s);
}

.job ul {
  margin-left: 1.5rem;
  color: var(--text-secondary);
}

.job ul li {
  margin-bottom: 0.5rem;
  line-height: 1.7;
}

.job a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: var(--margin-m);
  padding: 0.5rem 1rem;
  background-color: var(--bg-tertiary);
  border-radius: 6px;
  transition: var(--transition);
}

.job a:hover {
  background-color: var(--accent-warm);
  color: var(--bg-primary);
}

.job a svg {
  width: 20px;
  height: 20px;
}

.company {
  color: var(--accent-warm) !important;
  font-weight: 500;
  margin-bottom: var(--margin-xs) !important;
}

.company a {
  color: var(--accent-warm);
}

.company a:hover {
  color: var(--accent-warm-light);
}

.duration {
  color: var(--text-tertiary) !important;
  font-size: 0.875rem;
}

/* ===== PROJECT CARDS ===== */
.project-card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: var(--padding-xl);
  margin-bottom: var(--margin-xl);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  gap: var(--margin-m);
}

.project-card:hover {
  background-color: var(--bg-tertiary);
  border-color: var(--accent-warm);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.project-card img {
  width: 100%;
  height: auto;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.project-card:hover img {
  transform: scale(1.02);
}

.project-card h3 {
  color: var(--text-primary);
  margin-bottom: var(--margin-s);
}

.project-description {
  color: var(--text-secondary);
  font-size: 1rem;
  line-height: 1.7;
}

.tech-stack {
  display: flex;
  flex-wrap: wrap;
  gap: var(--margin-xs);
  margin: var(--margin-m) 0;
}

.tech-stack span {
  background-color: var(--bg-tertiary);
  color: var(--accent-warm);
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  font-size: 0.875rem;
  border: 1px solid var(--border-color);
  transition: var(--transition);
}

.tech-stack span:hover {
  background-color: var(--accent-warm);
  color: var(--bg-primary);
  border-color: var(--accent-warm);
}

.project-links {
  display: flex;
  gap: var(--margin-l);
  flex-wrap: wrap;
}

.project-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background-color: var(--bg-tertiary);
  border-radius: 6px;
  color: var(--accent-warm);
  transition: var(--transition);
}

.project-links a:hover {
  background-color: var(--accent-warm);
  color: var(--bg-primary);
}

.project-links svg {
  width: 20px;
  height: 20px;
}

/* ===== FEATURED PROJECT ===== */
.featured-project {
  border: 2px solid var(--accent-warm);
  position: relative;
  overflow: hidden;
}

.featured-project::before {
  content: "⭐ Featured";
  position: absolute;
  top: 15px;
  right: 15px;
  background-color: var(--accent-warm);
  color: var(--bg-primary);
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  z-index: 10;
}

/* ===== FAILURE CASE BLOCK ===== */
.failure-case-block {
  background-color: var(--bg-tertiary);
  border-left: 4px solid var(--accent-warm);
  border-radius: 8px;
  padding: var(--padding-l);
  margin: var(--margin-l) 0;
}

.failure-case-header {
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: var(--margin-m);
  color: var(--accent-warm);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.failure-case-content {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

.failure-input,
.failure-expected,
.failure-before,
.failure-causes,
.failure-fix,
.failure-result {
  margin-bottom: var(--margin-m);
}

.failure-input code {
  background-color: var(--bg-secondary);
  color: var(--accent-warm-light);
  padding: 2px 6px;
  border-radius: 4px;
}

.failure-badge {
  background-color: var(--bg-secondary);
  color: #ff9999;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
  border: 1px solid #ff9999;
}

.success-badge {
  background-color: var(--bg-secondary);
  color: #99dd99;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 600;
  border: 1px solid #99dd99;
}

.cause-list {
  margin-left: var(--margin-m);
  margin-top: 0.5rem;
  color: var(--text-secondary);
}

.cause-list li {
  margin-bottom: 0.5rem;
}

/* ===== FOOTER ===== */
.footer {
  display: flex;
  justify-content: center;
  gap: var(--margin-l);
  padding: var(--padding-xl) 0;
  border-top: 1px solid var(--border-color);
  margin-top: var(--margin-xxl);
}

.footer a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background-color: var(--bg-secondary);
  transition: var(--transition);
}

.footer a:hover {
  background-color: var(--accent-warm);
  transform: translateY(-4px);
}

.footer img {
  width: 30px;
  height: 30px;
  filter: brightness(0.9);
}

.footer a:hover img {
  filter: brightness(1.2);
}

/* ===== UTILITY CLASSES ===== */
.section-divider {
  border: none;
  height: 1px;
  background-color: var(--border-color);
  margin: var(--margin-xxl) 0;
}

.project-impact {
  text-align: center;
  color: var(--text-tertiary);
  font-size: 0.95rem;
  margin: var(--margin-xl) 0;
  font-style: italic;
}

/* ===== ANIMATIONS ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInHighlight {
  from {
    opacity: 0;
    transform: scaleX(0);
    transform-origin: left;
  }
  to {
    opacity: 1;
    transform: scaleX(1);
  }
}

.featured-project {
  animation: fadeInUp 0.6s ease-out;
}

.failure-case-block {
  animation: slideInHighlight 0.5s ease-out;
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.75rem;
  }

  h3 {
    font-size: 1.25rem;
  }

  .center-container {
    padding: var(--padding-m);
  }

  .connect {
    gap: var(--margin-m);
  }

  .connect a {
    padding: 0.5rem 0.75rem;
    font-size: 0.9rem;
  }

  .mode-area {
    top: var(--margin-s);
    right: var(--margin-s);
  }

  .project-links {
    flex-direction: column;
  }

  .project-links a {
    width: 100%;
    justify-content: center;
  }

  .tech-stack {
    gap: var(--margin-xs);
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  h3 {
    font-size: 1.1rem;
  }

  .connect {
    flex-direction: column;
    gap: var(--margin-m);
  }

  .connect a {
    width: 100%;
    justify-content: center;
  }

  .job,
  .project-card {
    padding: var(--padding-m);
  }

  .featured-project::before {
    top: 10px;
    right: 10px;
    font-size: 0.7rem;
    padding: 0.25rem 0.65rem;
  }
}