:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #a5b4fc;
    --accent: #14b8a6;
    --bg: #ffffff;
    --bg-muted: #f1f5f9;
    --bg-subtle: #f8fafc;
    --text: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --border: #e2e8f0;
    --card-shadow: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --card-hover-shadow: 0 12px 40px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.04);
    --category-project: #6366f1;
    --category-work: #10b981;
    --category-software: #8b5cf6;
    --category-hobby: #f59e0b;
    --category-project-bg: #eef2ff;
    --category-work-bg: #ecfdf5;
    --category-software-bg: #f5f3ff;
    --category-hobby-bg: #fffbeb;
    --radius: 12px;
    --radius-sm: 8px;
    --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

html, body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    color: var(--text);
    background: var(--bg-subtle);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    scroll-behavior: smooth;
}

h1, h2, h3 {
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text);
}

a {
    color: var(--primary);
    transition: color var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

/* ─── Animations ─── */

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

@keyframes float {
    0%, 100% { transform: translateY(0) scale(1); }
    50% { transform: translateY(-12px) scale(1.02); }
}

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

@keyframes countUp {
    from { opacity: 0; transform: scale(0.5); }
    to { opacity: 1; transform: scale(1); }
}

.animate-in {
    animation: fadeInUp 0.5s ease both;
}

/* ─── Hero ─── */

.hero {
    position: relative;
    background: linear-gradient(135deg, #111827, #1e293b, #0f172a, #111827);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    color: white;
    padding: 5rem 2.5rem;
    border-radius: var(--radius);
    margin-bottom: 3.5rem;
    text-align: center;
    overflow: hidden;
    isolation: isolate;
}

.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 20% 50%, rgba(99,102,241,0.12) 0%, transparent 55%),
        radial-gradient(ellipse at 80% 50%, rgba(20,184,166,0.08) 0%, transparent 55%);
    z-index: 0;
}

.hero::after {
    content: '';
    position: absolute;
    width: 500px;
    height: 500px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(99,102,241,0.05) 0%, transparent 65%);
    top: -150px;
    right: -150px;
    z-index: 0;
    animation: float 10s ease-in-out infinite;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-name {
    font-size: 3.25rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
    letter-spacing: -0.03em;
    background: linear-gradient(135deg, #ffffff 0%, #c7d2fe 50%, #5eead4 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 0.6s ease;
}

.hero-tagline {
    font-size: 1.15rem;
    color: rgba(255,255,255,0.65);
    max-width: 560px;
    margin: 0 auto 2.5rem;
    line-height: 1.75;
    font-weight: 400;
    animation: fadeInUp 0.6s ease 0.1s both;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 3.5rem;
    flex-wrap: wrap;
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.25rem;
    font-weight: 800;
    color: var(--accent);
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.stat-label {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.45);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-weight: 500;
}

/* ─── Section Headers ─── */

.section {
    margin-bottom: 3.5rem;
}

.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.section-header h2 {
    font-size: 1.5rem;
    margin: 0;
    position: relative;
}

.section-header h2::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 32px;
    height: 3px;
    background: var(--primary);
    border-radius: 2px;
}

.section-header a {
    font-size: 0.9rem;
    font-weight: 500;
}

/* ─── Skill Cloud ─── */

.skill-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.skill-badge {
    display: inline-flex;
    padding: 0.4rem 1rem;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all var(--transition);
    cursor: default;
}

.skill-badge:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99,102,241,0.25);
}

.skill-more {
    background: transparent;
    border-style: dashed;
    color: var(--text-muted);
}

.skill-more:hover {
    background: var(--bg-muted);
    border-color: var(--text-muted);
    color: var(--text-secondary);
    box-shadow: none;
    transform: none;
}

/* ─── Card Grid ─── */

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.25rem;
}

/* ─── Portfolio Card ─── */

.portfolio-card {
    position: relative;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--card-shadow);
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    text-decoration: none;
    color: inherit;
    overflow: hidden;
    background: var(--bg);
    animation: fadeInUp 0.4s ease both;
    animation-delay: calc(var(--i, 0) * 0.05s);
}

.portfolio-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--card-accent, var(--border));
    transition: height var(--transition);
}

.portfolio-card:hover {
    box-shadow: var(--card-hover-shadow);
    transform: translateY(-4px);
    border-color: var(--card-accent, var(--primary));
    color: inherit;
}

.portfolio-card:hover::before {
    height: 4px;
}

.card-body {
    padding: 1.5rem;
}

.card-category {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 0.75rem;
}

.card-category::before {
    content: '';
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: currentColor;
}

.card-category-project { color: var(--category-project); }
.card-category-work { color: var(--category-work); }
.card-category-software { color: var(--category-software); }
.card-category-hobby { color: var(--category-hobby); }

.card-title {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.card-text {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.card-skills {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    margin-top: 1rem;
}

.skill-tag {
    display: inline-flex;
    padding: 0.2rem 0.6rem;
    background: var(--bg-muted);
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: background var(--transition);
}

.portfolio-card:hover .skill-tag {
    background: var(--card-accent-bg, var(--bg-muted));
}

.skill-more-tag {
    color: var(--primary);
    font-weight: 600;
}

.card-links {
    display: flex;
    gap: 1rem;
    margin-top: 0.75rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border);
    font-size: 0.8rem;
}

.link-indicator {
    color: var(--primary);
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.link-indicator::before {
    content: '→';
    transition: transform var(--transition);
}

.portfolio-card:hover .link-indicator::before {
    transform: translateX(3px);
}

/* ─── Page Header Banner ─── */

.page-banner {
    padding: 2.5rem 2rem;
    border-radius: var(--radius);
    margin-bottom: 2.5rem;
    color: white;
}

.page-banner-project {
    background: linear-gradient(135deg, #4338ca, #6366f1);
}

.page-banner-work {
    background: linear-gradient(135deg, #065f46, #10b981);
}

.page-banner-software {
    background: linear-gradient(135deg, #5b21b6, #8b5cf6);
}

.page-banner-hobby {
    background: linear-gradient(135deg, #92400e, #f59e0b);
}

.page-banner h1 {
    color: white;
    font-size: 2rem;
    margin-bottom: 0.4rem;
}

.page-banner p {
    color: rgba(255,255,255,0.75);
    font-size: 1rem;
    margin: 0;
    max-width: 500px;
}

/* ─── Detail Page ─── */

.detail-page {
    max-width: 820px;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    margin-bottom: 1.5rem;
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
    transition: color var(--transition);
}

.back-link:hover {
    color: var(--primary);
    gap: 0.6rem;
}

.detail-card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--card-shadow);
    overflow: hidden;
}

.detail-banner {
    position: relative;
    padding: 2.5rem 2.5rem;
    color: white;
    overflow: hidden;
}

.detail-banner-projects {
    background: linear-gradient(135deg, #312e81, #6366f1);
}

.detail-banner-work {
    background: linear-gradient(135deg, #1a3d2e, #10b981);
}

.detail-banner-software {
    background: linear-gradient(135deg, #2d1b69, #8b5cf6);
}

.detail-banner-hobbies {
    background: linear-gradient(135deg, #4a2c0a, #f59e0b);
}

.detail-category-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    padding: 0.3rem 0.85rem;
    border-radius: 20px;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    background: rgba(255,255,255,0.15);
    backdrop-filter: blur(4px);
    color: rgba(255,255,255,0.9);
    margin-bottom: 0.75rem;
}

.detail-banner h1 {
    color: white;
    font-size: 2.25rem;
    font-weight: 700;
    margin: 0;
}

.detail-banner h1 small {
    font-size: 0.5em;
    opacity: 0.5;
    font-weight: 400;
}

.detail-banner-decoration {
    position: absolute;
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255,255,255,0.05) 0%, transparent 65%);
    top: -100px;
    right: -80px;
    z-index: 0;
}

.detail-banner > *:not(.detail-banner-decoration) {
    position: relative;
    z-index: 1;
}

.detail-content {
    padding: 2.5rem;
}

.detail-description {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text);
    margin-bottom: 2.5rem;
}

.detail-section {
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border);
}

.detail-section:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.detail-section h3 {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.detail-links {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

/* ─── Skill tag colors on detail page ─── */
.detail-page .skill-badge {
    background: var(--bg-muted);
}

.detail-page .skill-badge:hover {
    background: var(--primary);
}

/* ─── Buttons ─── */

.btn {
    padding: 0.5rem 1.25rem;
    font-size: 0.9rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    transition: all var(--transition);
}

.btn-primary {
    background: var(--primary);
    border-color: var(--primary);
}

.btn-primary:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99,102,241,0.3);
}

.btn-outline-primary {
    color: var(--primary);
    border-color: var(--primary);
}

.btn-outline-primary:hover {
    background: var(--primary);
    border-color: var(--primary);
    transform: translateY(-1px);
}

.btn-outline-secondary {
    color: var(--text-secondary);
    border-color: var(--border);
}

.btn-outline-secondary:hover {
    color: var(--text);
    border-color: var(--text-muted);
    background: var(--bg-muted);
    transform: translateY(-1px);
}

.see-all-btn {
    margin-top: 1.5rem;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
}

.see-all-btn::after {
    content: '→';
    transition: transform var(--transition);
}

.see-all-btn:hover::after {
    transform: translateX(3px);
}

/* ─── Load Screen ─── */

@keyframes spin {
    to { transform: rotate(360deg); }
}

@keyframes loadPulse {
    0%, 100% { opacity: 0.4; }
    50% { opacity: 1; }
}

.load-screen {
    position: fixed;
    inset: 0;
    background: #111827;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
    z-index: 9999;
}

.load-logo {
    width: 56px;
    height: 56px;
    border: 2px solid rgba(255,255,255,0.2);
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Inter', system-ui, sans-serif;
    font-weight: 700;
    font-size: 1.2rem;
    color: white;
}

.load-spinner {
    width: 28px;
    height: 28px;
    border: 2.5px solid rgba(255,255,255,0.08);
    border-top-color: #6366f1;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
}

.load-text {
    font-family: 'Inter', system-ui, sans-serif;
    font-size: 0.85rem;
    font-weight: 500;
    color: rgba(255,255,255,0.45);
    letter-spacing: 0.04em;
    animation: loadPulse 2s ease-in-out infinite;
}

/* ─── Not Found ─── */

.not-found-page {
    text-align: center;
    padding: 5rem 0;
}

.not-found-page h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.not-found-page p {
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

/* ─── Responsive ─── */

@media (max-width: 768px) {
    .hero {
        padding: 3rem 1.5rem;
    }

    .hero-name {
        font-size: 2.25rem;
    }

    .hero-stats {
        gap: 2rem;
    }

    .stat-number {
        font-size: 1.75rem;
    }

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

    .page-banner {
        padding: 1.75rem 1.25rem;
    }

    .page-banner h1 {
        font-size: 1.5rem;
    }

    .detail-banner {
        padding: 1.75rem 1.25rem;
    }

    .detail-banner h1 {
        font-size: 1.5rem;
    }

    .detail-content {
        padding: 1.5rem;
    }

    .detail-description {
        font-size: 1rem;
    }
}

/* ─── Utility ─── */

.text-muted {
    color: var(--text-muted);
}