/* CSS Variables */
:root {
    --accent: #3b82f6;
    --accent-dark: #2563eb;
    --bg: #f8fafc;
    --bg-card: #ffffff;
    --bg-sidebar: #f1f5f9;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-hover: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    --accent: #60a5fa;
    --accent-dark: #3b82f6;
    --bg: #0f172a;
    --bg-card: #1e293b;
    --bg-sidebar: #1e293b;
    --text: #f1f5f9;
    --text-muted: #94a3b8;
    --border: #334155;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
    --shadow-hover: 0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    transition: background 0.3s, color 0.3s;
}

.app-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background: var(--bg-sidebar);
    border-left: 1px solid var(--border);
    position: fixed;
    right: 0;
    top: 0;
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2.5rem 1.5rem;
    z-index: 100;
    transition: var(--transition);
}

.profile-img {
    width: 126px;
    height: 126px;
    margin-bottom: 2rem;
    position: relative;
    border-radius: 50%;
    background: linear-gradient(135deg, #8ec5ff 0%, #4f8df7 55%, #2d5fd3 100%);
    padding: 4px;
    box-shadow: 0 8px 18px rgba(79, 141, 247, 0.18);
}

.profile-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center 23%;
    border-radius: 50%;
    border: 4px solid var(--bg-sidebar);
    display: block;
    transform: scale(1.34);
    box-shadow: 0 0 0 2px rgba(186, 220, 255, 0.7);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.profile-img img:hover {
    transform: scale(1.4);
}

.nav-links {
    list-style: none;
    width: 100%;
    text-align: center;
}

.nav-links li {
    margin-bottom: 0.75rem;
}

.nav-links a {
    display: block;
    padding: 0.875rem 1.25rem;
    color: var(--text);
    text-decoration: none;
    font-weight: 600;
    border-radius: var(--radius);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.nav-links a::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 0;
    background: var(--accent);
    transition: width 0.3s ease;
    z-index: -1;
}

.nav-links a:hover::before,
.nav-links a.active::before {
    width: 100%;
}

.nav-links a:hover,
.nav-links a.active {
    color: #fff;
    transform: translateX(-4px);
}

/* Theme Toggle */
.theme-toggle {
    margin-top: auto;
    background: var(--bg-card);
    border: 2px solid var(--border);
    color: var(--text);
    padding: 0.75rem;
    cursor: pointer;
    font-size: 1.1rem;
    margin-bottom: 1rem;
    border-radius: 50%;
    width: 45px;
    height: 45px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.theme-toggle:hover {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    transform: rotate(20deg) scale(1.1);
}

/* Main Content */
.content {
    margin-right: 280px;
    padding: 3rem;
    flex: 1;
    max-width: 1200px;
    min-height: 100vh;
    background: var(--bg);
}

/* Typography */
.section-label {
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.section-label::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--accent);
    opacity: 0.3;
    max-width: 60px;
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.25rem;
    color: var(--text);
    letter-spacing: -0.02em;
}

.hero-title .highlight {
    color: var(--accent);
    position: relative;
}

.hero-title .highlight::after {
    content: '';
    position: absolute;
    bottom: 4px;
    left: 0;
    width: 100%;
    height: 8px;
    background: var(--accent);
    opacity: 0.2;
    border-radius: 4px;
    z-index: -1;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2.5rem;
    padding-bottom: 1rem;
    border-bottom: 3px solid var(--accent);
    display: inline-block;
    font-weight: 500;
}

.description {
    font-size: 1.125rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
    max-width: 700px;
    line-height: 1.8;
}

/* Section Headers */
.section-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 1.5rem;
    padding-left: 1.25rem;
    border-left: 4px solid var(--accent);
    position: relative;
}

/* Content wrapper */
.content-wrapper {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.content-wrapper:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-2px);
}

/* Lists */
.skill-list {
    list-style: none;
}

.skill-list li {
    padding: 1rem 0;
    border-bottom: 1px solid var(--border);
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: var(--transition);
}

.skill-list li:hover {
    color: var(--text);
    padding-left: 0.5rem;
}

.skill-list li:last-child {
    border-bottom: none;
}

.skill-list .icon {
    color: var(--accent);
    font-size: 1.1rem;
    width: 24px;
    text-align: center;
}

.skill-list strong {
    color: var(--text);
    font-weight: 600;
}

/* Project Cards */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.project-card {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--accent), var(--accent-dark));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.project-card:hover::before {
    transform: scaleX(1);
}

.project-card:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-4px);
}

.project-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.project-header i {
    font-size: 1.5rem;
    color: var(--accent);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg);
    border-radius: 10px;
}

.project-card h3 {
    color: var(--text);
    font-size: 1.25rem;
    font-weight: 700;
}

.project-card p {
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 1.25rem;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    background: var(--bg);
    color: var(--accent);
    border: 1px solid var(--border);
    padding: 0.375rem 0.875rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    transition: var(--transition);
}

.tag:hover {
    background: var(--accent);
    color: #fff;
}

/* Skill Bars */
.skill-bars {
    margin-top: 1rem;
}

.skill-item {
    margin-bottom: 1.5rem;
}

.skill-name {
    display: flex;
    justify-content: space-between;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 0.75rem;
}

.skill-bar {
    background: var(--border);
    height: 10px;
    border-radius: 5px;
    overflow: hidden;
}

.skill-progress {
    background: linear-gradient(90deg, var(--accent), var(--accent-dark));
    height: 100%;
    border-radius: 5px;
    width: 0;
    transition: width 1.5s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}

.skill-progress::after {
    content: '';
    position: absolute;
    right: 0;
    top: 0;
    height: 100%;
    width: 20px;
    background: rgba(255,255,255,0.3);
    border-radius: 0 5px 5px 0;
}

/* Contact Info */
.contact-info {
    margin-top: 1.5rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 0;
    color: var(--text-muted);
    transition: var(--transition);
}

.contact-item:hover {
    color: var(--text);
    padding-left: 0.5rem;
}

.contact-item i {
    color: var(--accent);
    font-size: 1.25rem;
    width: 24px;
    text-align: center;
}

/* Social Links */
.social-links {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 1rem;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    padding: 0.875rem 1.75rem;
    background: var(--bg-card);
    color: var(--text);
    text-decoration: none;
    font-weight: 600;
    border-radius: var(--radius);
    border: 2px solid var(--border);
    transition: var(--transition);
    gap: 0.75rem;
}

.social-links a:hover {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.social-links i {
    font-size: 1.1rem;
}

/* Mobile Menu Button */
.hamburger {
    display: none;
    position: fixed;
    right: 1rem;
    top: 1rem;
    z-index: 101;
    background: var(--accent);
    color: #fff;
    border: none;
    padding: 0.875rem;
    cursor: pointer;
    font-size: 1.25rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.hamburger:hover {
    background: var(--accent-dark);
    transform: scale(1.05);
}

/* Sections */
section {
    display: none;
    padding: 2rem 0;
    animation: fadeIn 0.5s ease;
}

section.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Responsive */
@media (max-width: 1024px) {
    .content {
        margin-right: 0;
        padding: 5rem 1.5rem 2rem;
        width: 100%;
    }

    .sidebar {
        right: -280px;
        box-shadow: var(--shadow-hover);
    }

    .sidebar.active {
        right: 0;
    }

    .hamburger {
        display: flex;
    }

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

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

@media (max-width: 640px) {
    .hero-title {
        font-size: 1.875rem;
    }

    .content {
        padding: 4rem 1rem 2rem;
    }

    .content-wrapper {
        padding: 1.5rem;
    }

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

    .social-links a {
        justify-content: center;
    }
}