/* ============================================
   Portfolio — Apple-Inspired Design System
   With Dark Mode & Enhanced Animations
   ============================================ */

/* ── CSS Custom Properties (Light Mode) ── */
:root {
  --color-bg: #ffffff;
  --color-bg-secondary: #f5f5f7;
  --color-bg-tertiary: #e8e8ed;
  --color-text-primary: #1d1d1f;
  --color-text-secondary: #6e6e73;
  --color-text-tertiary: #6e6e73;
  --color-accent: #0066cc;
  --color-accent-hover: #004499;
  --color-accent-glow: rgba(0, 102, 204, 0.3);
  --color-border: #d2d2d7;
  --color-border-light: #e8e8ed;
  --color-nav-bg: rgba(255, 255, 255, 0.72);
  --color-card-bg: #ffffff;
  --color-shadow: rgba(0, 0, 0, 0.08);
  --color-shadow-hover: rgba(0, 0, 0, 0.15);
  --color-gradient-1: linear-gradient(135deg, #0066cc, #5856d6);
  --color-gradient-2: linear-gradient(135deg, #5856d6, #af52de);
  --color-gradient-3: linear-gradient(135deg, #ff9500, #ffcc02);
  --color-gradient-4: linear-gradient(135deg, #34c759, #30d158);
  --color-gradient-5: linear-gradient(135deg, #ff2d55, #ff3b30);
  --color-hero-bg: #ffffff;
  --color-stat-bg: transparent;
  --color-tag-bg: #f5f5f7;
  --color-tag-text: #6e6e73;
  --color-input-bg: #ffffff;
  --color-success: #34c759;
  --color-error: #ff3b30;

  /* Typography */
  --font-primary: -apple-system, 'SF Pro Display', 'SF Pro Text', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;

  /* Sizing */
  --nav-height: 48px;
  --section-padding: 120px 0;
  --max-width: 1068px;
  --max-width-wide: 1440px;
  --grid-gap: 24px;

  /* Transitions */
  --transition-fast: 0.2s cubic-bezier(0.25, 0.1, 0.25, 1);
  --transition-medium: 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
  --transition-slow: 0.6s cubic-bezier(0.25, 0.1, 0.25, 1);
  --transition-bounce: 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.12);
  --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.15);
}

/* ── Dark Mode ── */
[data-theme="dark"] {
  --color-bg: #000000;
  --color-bg-secondary: #1d1d1f;
  --color-bg-tertiary: #2d2d2f;
  --color-text-primary: #f5f5f7;
  --color-text-secondary: #98989d;
  --color-text-tertiary: #6e6e73;
  --color-accent: #409cff;
  --color-accent-hover: #66b0ff;
  --color-accent-glow: rgba(64, 156, 255, 0.3);
  --color-border: #424245;
  --color-border-light: #2d2d2f;
  --color-nav-bg: rgba(0, 0, 0, 0.8);
  --color-card-bg: #1d1d1f;
  --color-shadow: rgba(0, 0, 0, 0.3);
  --color-shadow-hover: rgba(64, 156, 255, 0.2);
  --color-gradient-1: linear-gradient(135deg, #409cff, #7b7bff);
  --color-gradient-2: linear-gradient(135deg, #7b7bff, #d483ff);
  --color-gradient-3: linear-gradient(135deg, #ff9f0a, #ffd60a);
  --color-gradient-4: linear-gradient(135deg, #30d158, #34c759);
  --color-gradient-5: linear-gradient(135deg, #ff453a, #ff375f);
  --color-hero-bg: #000000;
  --color-stat-bg: #1d1d1f;
  --color-tag-bg: #2d2d2f;
  --color-tag-text: #98989d;
  --color-input-bg: #1d1d1f;
  --color-success: #30d158;
  --color-error: #ff453a;
}

/* Smooth theme transition */
*,
*::before,
*::after {
  transition: background-color 0.3s ease,
              border-color 0.3s ease,
              color 0.3s ease,
              box-shadow 0.3s ease;
}

/* ── Reset & Base ── */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  color: var(--color-text-primary);
  background: var(--color-bg);
  line-height: 1.47059;
  letter-spacing: -0.022em;
  overflow-x: hidden;
}

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

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

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

/* ── Language Toggle ── */
.lang-toggle {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  cursor: pointer;
  padding: 4px 10px;
  font-size: 11px;
  font-weight: 600;
  font-family: var(--font-primary);
  letter-spacing: 0.02em;
  color: var(--color-text-primary);
  opacity: 0.8;
  transition: all var(--transition-fast);
}

.lang-toggle:hover {
  opacity: 1;
  background: var(--color-bg-secondary);
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ── Dark Mode Toggle ── */
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-primary);
  opacity: 0.8;
  transition: all var(--transition-fast);
  position: relative;
  width: 32px;
  height: 32px;
}

.theme-toggle:hover {
  opacity: 1;
  background: var(--color-bg-secondary);
}

.theme-toggle svg {
  width: 18px;
  height: 18px;
  transition: transform var(--transition-bounce);
}

.theme-toggle:hover svg {
  transform: rotate(15deg);
}

.theme-toggle .sun-icon {
  display: none;
}

.theme-toggle .moon-icon {
  display: block;
}

[data-theme="dark"] .theme-toggle .sun-icon {
  display: block;
}

[data-theme="dark"] .theme-toggle .moon-icon {
  display: none;
}

/* ── Navigation ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--color-nav-bg);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  z-index: 1000;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-fast), background var(--transition-fast);
}

.nav.scrolled {
  border-bottom-color: var(--color-border);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 22px;
}

.nav-left {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-logo {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--color-text-primary);
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-logo svg {
  width: 18px;
  height: 18px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-link {
  font-size: 12px;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--color-text-primary);
  opacity: 0.8;
  transition: opacity var(--transition-fast);
  text-decoration: none;
}

.nav-link:hover {
  opacity: 1;
  color: var(--color-text-primary);
}

.nav-link.active {
  opacity: 1;
  color: var(--color-accent);
}

/* Mobile nav toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 1px;
  background: var(--color-text-primary);
  margin: 5px 0;
  transition: all var(--transition-fast);
}

/* ── Hero Section ── */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  text-align: left;
  padding: 0 0 80px;
  padding-top: calc(var(--nav-height) + 60px);
  position: relative;
  overflow: hidden;
  background: var(--color-hero-bg);
}

.hero::before {
  content: '';
  position: absolute;
  top: 30%;
  left: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--color-accent-glow) 0%, transparent 70%);
  opacity: 0.12;
  pointer-events: none;
}

/* Container căn trái, giới hạn chiều rộng */
.hero-container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 22px;
  display: flex;
  align-items: center;
  flex: 1;
}

.hero-content {
  max-width: 800px;
  width: 100%;
  text-align: left;
  transition: transform 0.1s ease-out, opacity 0.1s ease-out;
  will-change: transform, opacity;
  position: relative;
  z-index: 1;
}

.hero-subtitle {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 24px;
  opacity: 0;
  transform: translateY(20px);
  animation: fadeUp 0.8s cubic-bezier(0.25, 0.1, 0.25, 1) 0.2s forwards;
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
}

.hero-subtitle::before {
  content: '';
  display: inline-block;
  width: 32px;
  height: 2px;
  background: var(--color-accent);
  border-radius: 1px;
  flex-shrink: 0;
}

.hero-title {
  font-size: clamp(40px, 6.5vw, 76px);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.08;
  margin-bottom: 28px;
  max-width: 780px;
  opacity: 0;
  transform: translateY(30px);
  animation: fadeUp 0.8s cubic-bezier(0.25, 0.1, 0.25, 1) 0.4s forwards;
  position: relative;
}

.hero-title .highlight {
  background: var(--color-gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-description {
  font-size: clamp(16px, 1.6vw, 20px);
  font-weight: 400;
  color: var(--color-text-secondary);
  max-width: 580px;
  line-height: 1.65;
  margin-bottom: 40px;
  opacity: 0;
  transform: translateY(20px);
  animation: fadeUp 0.8s cubic-bezier(0.25, 0.1, 0.25, 1) 0.6s forwards;
  position: relative;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: flex-start;
  flex-wrap: wrap;
  opacity: 0;
  transform: translateY(20px);
  animation: fadeUp 0.8s cubic-bezier(0.25, 0.1, 0.25, 1) 0.8s forwards;
}

.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  opacity: 0;
  animation: fadeUp 0.8s cubic-bezier(0.25, 0.1, 0.25, 1) 1.2s forwards;
  cursor: pointer;
}

.hero-scroll span {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
}

.scroll-indicator {
  width: 1px;
  height: 32px;
  background: var(--color-text-tertiary);
  animation: scrollPulse 2s ease-in-out infinite;
}

/* ── Stats Section ── */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
  text-align: center;
}

.stat-item {
  padding: 32px 24px;
  border-radius: 16px;
  background: var(--color-stat-bg);
  transition: all var(--transition-medium);
  position: relative;
  overflow: hidden;
}

.stat-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-gradient-1);
  opacity: 0;
  transform: scaleX(0);
  transition: all var(--transition-slow);
}

.stat-item:hover::before {
  opacity: 1;
  transform: scaleX(1);
}

.stat-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.stat-number {
  font-size: 48px;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1;
  margin-bottom: 8px;
  background: var(--color-gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 980px;
  font-size: 14px;
  font-weight: 400;
  letter-spacing: -0.01em;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  text-decoration: none;
  font-family: var(--font-primary);
  position: relative;
  overflow: hidden;
}

.btn::after {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(255, 255, 255, 0.1);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.btn:hover::after {
  opacity: 1;
}

.btn-primary {
  background: var(--color-accent);
  color: #ffffff;
}

.btn-primary:hover {
  background: var(--color-accent-hover);
  color: #ffffff;
  transform: scale(1.02);
  box-shadow: 0 4px 16px var(--color-accent-glow);
}

.btn-secondary {
  background: transparent;
  color: var(--color-accent);
  border: 1px solid var(--color-accent);
}

.btn-secondary:hover {
  background: var(--color-accent);
  color: #ffffff;
  transform: scale(1.02);
  box-shadow: 0 4px 16px var(--color-accent-glow);
}

.btn-outline {
  background: transparent;
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
}

.btn-outline:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: transparent;
}

/* ── Section Styles ── */
.section {
  padding: var(--section-padding);
  position: relative;
}

/* Header section trên các trang nội dung (about, projects, contact) */
.page-hero {
  padding-top: calc(var(--nav-height) + 80px);
  padding-bottom: 60px;
}

/* reveal trong page-hero: visible ngay, không translateY (tránh đè navbar khi JS chưa chạy) */
.page-hero .reveal {
  opacity: 1;
  transform: translateY(0);
  transition: none;
}

@media (max-width: 768px) {
  .page-hero {
    padding-top: calc(var(--nav-height) + 48px);
    padding-bottom: 40px;
  }
}

.section-alt {
  background: var(--color-bg-secondary);
}

.section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 22px;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(32px, 5vw, 56px);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.1;
  margin-bottom: 16px;
}

.section-description {
  font-size: 18px;
  color: var(--color-text-secondary);
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.6;
}

/* ── About Page ── */
.about-single-col {
  max-width: 720px;
  margin: 0 auto;
}

.about-single-col h2 {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  background: var(--color-gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.about-single-col p {
  font-size: 17px;
  line-height: 1.75;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
}

.about-single-col strong {
  color: var(--color-text-primary);
}

/* Legacy about-grid (kept for fallback, hidden) */
.about-grid {
  display: none;
}

.about-content h2 {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  background: var(--color-gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.about-content p {
  font-size: 17px;
  line-height: 1.7;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

.about-content strong {
  color: var(--color-text-primary);
}

.skills-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  list-style: none;
  margin-top: 32px;
}

.skills-grid li {
  padding: 8px 16px;
  background: var(--color-card-bg);
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-fast);
}

.skills-grid li:hover {
  border-color: var(--color-accent);
  transform: translateX(4px);
  box-shadow: 0 2px 8px var(--color-accent-glow);
}

.skills-grid li::before {
  content: "▹";
  color: var(--color-accent);
  font-size: 12px;
}

/* Experience timeline */
.experience-item {
  padding: 20px 0;
  border-bottom: 1px solid var(--color-border-light);
  transition: all var(--transition-fast);
}

.experience-item:last-child {
  border-bottom: none;
}

.experience-item:hover {
  padding-left: 12px;
}

.experience-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 8px;
  flex-wrap: wrap;
  gap: 4px;
}

.experience-header h3 {
  font-size: 17px;
  font-weight: 600;
}

.experience-date {
  font-size: 13px;
  color: var(--color-text-tertiary);
  font-weight: 400;
}

.experience-company {
  font-size: 14px;
  color: var(--color-accent);
  margin-bottom: 8px;
  font-weight: 500;
}

.experience-list {
  list-style: none;
}

.experience-list li {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.6;
  padding: 4px 0;
  padding-left: 16px;
  position: relative;
}

.experience-list li::before {
  content: '—';
  position: absolute;
  left: 0;
  color: var(--color-accent);
}

.metric {
  color: var(--color-accent);
  font-weight: 600;
}

/* Education card */
.education-card {
  padding: 20px;
  border-radius: 16px;
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  transition: all var(--transition-fast);
}

.education-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
}

.education-card h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 4px;
}

.education-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.education-card .education-detail {
  font-size: 13px;
  color: var(--color-text-tertiary);
  margin-bottom: 2px;
}

/* ── Projects Grid ── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--grid-gap);
}

.project-card {
  background: var(--color-card-bg);
  border-radius: 20px;
  overflow: hidden;
  transition: all var(--transition-medium);
  border: 1px solid var(--color-border);
  cursor: pointer;
  opacity: 0;
  transform: translateY(30px);
}

.project-card.visible {
  opacity: 1;
  transform: translateY(0);
}

.project-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-xl);
  border-color: transparent;
}

.project-card-image {
  aspect-ratio: 16/10;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
}

.project-card-image .card-icon {
  font-size: 48px;
  opacity: 0.8;
  position: relative;
  z-index: 1;
  transition: transform var(--transition-bounce);
}

.project-card-image .card-icon-img {
  width: 56px;
  height: 56px;
  position: relative;
  z-index: 1;
  filter: brightness(0) invert(1);
  transition: transform var(--transition-bounce);
}

.project-card:hover .card-icon,
.project-card:hover .card-icon-img {
  transform: scale(1.1) rotate(-5deg);
}

.project-card-body {
  padding: 24px;
}

.project-card-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.project-card-tag {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.02em;
  padding: 4px 10px;
  border-radius: 100px;
  background: var(--color-tag-bg);
  color: var(--color-tag-text);
  transition: all var(--transition-fast);
}

.project-card-tag:hover {
  background: var(--color-accent);
  color: #ffffff;
}

.project-card-title {
  font-size: 20px;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.project-card-description {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.project-card-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-top: 16px;
  font-size: 14px;
  font-weight: 500;
}

.project-card-link svg {
  transition: transform var(--transition-fast);
}

.project-card-link:hover svg {
  transform: translateX(4px);
}

/* ── Project Card Tag Icons ── */
.project-card-tags {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.project-card-tags img,
.project-card-tag img {
  width: 14px;
  height: 14px;
  vertical-align: middle;
  display: inline-block;
  flex-shrink: 0;
  object-fit: contain;
}

/* ── Contact Page ── */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 16px;
  border-radius: 16px;
  transition: all var(--transition-fast);
}

.contact-item:hover {
  background: var(--color-bg-secondary);
}

.contact-item-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--color-bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 20px;
  color: var(--color-accent);
}

.contact-item h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
}

.contact-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-group label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
  margin-bottom: 8px;
  display: block;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 14px 16px;
  font-size: 16px;
  font-family: var(--font-primary);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  background: var(--color-input-bg);
  color: var(--color-text-primary);
  transition: all var(--transition-fast);
  outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-glow);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--color-text-tertiary);
}

.form-group textarea {
  min-height: 140px;
  resize: vertical;
}

/* ── Availability Badge ── */
.availability-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-card-bg);
  padding: 8px 20px;
  border-radius: 100px;
  border: 1px solid var(--color-border);
}

.availability-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-success);
  display: inline-block;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.8); }
}

/* ── Tech Stack with Icons ── */
.tech-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  max-width: 620px;
  margin: 0 auto;
}

.tech-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 500;
  padding: 8px 16px;
  border-radius: 100px;
  background: var(--color-tag-bg);
  color: var(--color-tag-text);
  border: 1px solid var(--color-border);
  transition: all var(--transition-fast);
  cursor: default;
}

.tech-tag img {
  width: 18px;
  height: 18px;
  transition: transform var(--transition-bounce);
}

.tech-tag:hover {
  background: var(--color-accent);
  color: #ffffff;
  border-color: var(--color-accent);
  transform: translateY(-3px);
  box-shadow: 0 4px 12px var(--color-accent-glow);
}

.tech-tag:hover img {
  transform: scale(1.2);
  filter: brightness(0) invert(1);
}

/* Icon-only tag (no text) */
.tech-icon-tag {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  padding: 8px;
  border-radius: 12px;
  background: var(--color-tag-bg);
  border: 1px solid var(--color-border);
  transition: all var(--transition-fast);
  cursor: default;
}

.tech-icon-tag img {
  width: 24px;
  height: 24px;
  transition: transform var(--transition-bounce);
}

.tech-icon-tag:hover {
  background: var(--color-accent);
  border-color: var(--color-accent);
  transform: translateY(-3px);
  box-shadow: 0 4px 12px var(--color-accent-glow);
}

.tech-icon-tag:hover img {
  transform: scale(1.2);
  filter: brightness(0) invert(1);
}

/* ── Animations ── */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes scrollPulse {
  0%, 100% { opacity: 1; transform: scaleY(1); }
  50% { opacity: 0.3; transform: scaleY(0.6); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

@keyframes shimmer {
  0% { background-position: -200% center; }
  100% { background-position: 200% center; }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.95);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* ── Reveal on Scroll ── */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all var(--transition-slow);
}

.reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }

/* Staggered reveal for grid items */
.stagger-children > * {
  opacity: 0;
  transform: translateY(20px);
  transition: all var(--transition-slow);
}

.stagger-children.revealed > *:nth-child(1) { transition-delay: 0s; }
.stagger-children.revealed > *:nth-child(2) { transition-delay: 0.1s; }
.stagger-children.revealed > *:nth-child(3) { transition-delay: 0.2s; }
.stagger-children.revealed > *:nth-child(4) { transition-delay: 0.3s; }
.stagger-children.revealed > *:nth-child(5) { transition-delay: 0.4s; }
.stagger-children.revealed > *:nth-child(6) { transition-delay: 0.5s; }

.stagger-children.revealed > * {
  opacity: 1;
  transform: translateY(0);
}

/* ── Skip to Main Content (Accessibility) ── */
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  z-index: 10000;
  padding: 8px 16px;
  background: var(--color-accent);
  color: #fff;
  font-size: 14px;
  text-decoration: none;
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 0;
  color: #fff;
}

/* ── Page Transitions ── */
.page-transition {
  animation: fadeIn 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
}

/* ── Call to Action Section ── */
.cta-section {
  text-align: center;
  background: var(--color-bg-secondary);
  padding: var(--section-padding);
}

/* ── Responsive ── */  @media (max-width: 768px) {
  .nav-links {
    display: flex;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--color-nav-bg);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    flex-direction: column;
    padding: 0 22px;
    gap: 0;
    border-bottom: 1px solid var(--color-border);
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.25, 0.1, 0.25, 1),
                opacity 0.3s cubic-bezier(0.25, 0.1, 0.25, 1),
                padding 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
  }

  .nav-links.open {
    max-height: 300px;
    opacity: 1;
    padding: 16px 22px;
  }

  .nav-links .nav-link {
    padding: 8px 0;
    display: block;
  }

  .nav-toggle {
    display: block;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .about-visual {
    position: static;
    aspect-ratio: 16/9;
  }

  .contact-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .skills-grid {
    grid-template-columns: 1fr;
  }

  .projects-grid {
    grid-template-columns: 1fr;
  }

  .hero-title {
    font-size: clamp(32px, 10vw, 52px);
  }

  .hero-description {
    font-size: 16px;
    max-width: 100%;
  }

  .section {
    padding: 80px 0;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .stat-item {
    padding: 24px 16px;
  }

  .stat-number {
    font-size: 36px;
  }
}

@media (max-width: 480px) {
  .nav-inner {
    padding: 0 16px;
  }

  .hero {
    padding-left: 16px;
    padding-right: 16px;
  }

  .section-inner {
    padding: 0 16px;
  }

  .hero-actions {
    flex-direction: column;
    width: 100%;
  }

  .hero-actions .btn {
    width: 100%;
    justify-content: center;
  }

  .stats-grid {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }
}

/* ── Footer ── */
.footer {
  border-top: 1px solid var(--color-border);
  padding: 40px 0;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 22px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-text {
  font-size: 12px;
  color: var(--color-text-tertiary);
}

.footer-links {
  display: flex;
  gap: 24px;
  list-style: none;
}

.footer-links a {
  font-size: 12px;
  color: var(--color-text-tertiary);
  transition: color var(--transition-fast);
}

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

/* ── Utility ── */
.text-gradient {
  background: var(--color-gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.text-center {
  text-align: center;
}

.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mt-48 { margin-top: 48px; }