:root {
  --bg-main: #050505;
  --bg-alt: #141414;
  --bg-card: #1f1f1f;
  --bg-card-soft: #262626;
  --accent: #ffffff;
  --accent-subtle: #00c3ff;
  --text-main: #f5f5f5;
  --text-muted: #b0b0b0;
  --border-soft: rgba(255, 255, 255, 0.12);
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-pill: 999px;
  --shadow-soft: 0 18px 45px rgba(0, 0, 0, 0.55);
  --container-width: 1120px;
}

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

html,
body {
  margin: 0;
  padding: 0;
}

body {
  font-family: "Poppins", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-main);
  color: var(--text-main);
  line-height: 1.6;
}

/* ========== HEADER ========== */
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
}

.logo {
    font-size: 1.0em;
    font-weight: 700;
    color: #fff;
    text-decoration: none; /* important */
    cursor: pointer;
}
.logo:hover {
    opacity: 0.8;
}

.nav {
  display: flex;
  gap: 1.25rem;
}

.nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  position: relative;
  padding-bottom: 0.25rem;
}



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

.nav a:hover::after {
  width: 100%;
}

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(10px);
    padding: 1rem 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: #00d4ff;
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-link {
    color: #e0e0e0;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-link:hover {
    color: #00d4ff;
}

.footer {
    background: #0a0a0a;
    padding: 2rem 0;
    text-align: center;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: 4rem;
}

.footer p {
    color: #888;
    margin: 0;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: #0a0e1a;
    color: #e4e6eb;
    line-height: 1.6;
}

/* ========== SECTION STYLES ========== */
.section {
    padding: 80px 20px;
    background: linear-gradient(180deg, #0a0e1a 0%, #0f1420 100%);
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

.section-title {
    font-size: 3rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #00d9ff 0%, #0080ff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInDown 0.8s ease-out;
}

.section-subtitle {
    text-align: center;
    font-size: 1.125rem;
    color: #a0a8b8;
    margin-bottom: 4rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}



/* ========== NOTES SECTION ========== */
.notes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.5rem;
  margin-top: 2.5rem;
}

.note-card {
  background: linear-gradient(135deg, rgba(30, 30, 30, 0.9) 0%, rgba(20, 20, 20, 0.95) 100%);
  border-radius: 16px;
  padding: 1.75rem;
  border: 1px solid rgba(0, 195, 255, 0.15);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.note-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-subtle), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.note-card:hover {
  transform: translateY(-6px);
  border-color: rgba(0, 195, 255, 0.4);
  box-shadow: 0 12px 30px rgba(0, 195, 255, 0.2);
}

.note-card:hover::before {
  opacity: 1;
}

.note-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
  gap: 0.75rem;
}

.note-date {
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.note-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  justify-content: flex-end;
}
.note-link {
    text-decoration: none;
    color: inherit;
}

.note-tag {
  background: rgba(0, 195, 255, 0.1);
  border: 1px solid rgba(0, 195, 255, 0.3);
  color: var(--accent-subtle);
  padding: 4px 10px;
  border-radius: 12px;
  font-size: 0.7rem;
  font-weight: 500;
  transition: all 0.2s ease;
}

.note-card:hover .note-tag {
  background: rgba(0, 195, 255, 0.2);
  border-color: rgba(0, 195, 255, 0.5);
}

.note-title {
  margin: 0 0 0.75rem;
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--accent);
  line-height: 1.3;
}

.note-excerpt {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--text-muted);
}