/* =============================================
   CSS CUSTOM PROPERTIES (variables)
   Dark mode works by changing these variables —
   everything that uses them updates automatically.
   ============================================= */
:root {
    --bg-primary:    #ffffff;
    --bg-secondary:  #f8f9fa;
    --bg-card:       #ffffff;
    --text-primary:  #0a0a0a;
    --text-secondary:#555555;
    --text-muted:    #888888;
    --accent:        #6c3bff;
    --accent-hover:  #5429e0;
    --border:        #e5e5e5;
    --nav-bg:        rgba(255, 255, 255, 0.85);
    --shadow:        0 4px 24px rgba(0,0,0,0.08);
}

/* Dark mode — applied when <html> has class "dark" */
html.dark {
    --bg-primary:    #0a0a0f;
    --bg-secondary:  #111118;
    --bg-card:       #16161f;
    --text-primary:  #f0f0f0;
    --text-secondary:#aaaaaa;
    --text-muted:    #666666;
    --accent:        #8b6fff;
    --accent-hover:  #a084ff;
    --border:        #2a2a3a;
    --nav-bg:        rgba(10, 10, 15, 0.85);
    --shadow:        0 4px 24px rgba(0,0,0,0.4);
}

/* =============================================
   RESET & BASE
   ============================================= */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
    line-height: 1.6;
    overflow-x: hidden; /* prevent horizontal scroll on mobile */
}

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

/* =============================================
   NAVBAR
   ============================================= */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: var(--nav-bg);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: background 0.3s ease;
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2rem;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    letter-spacing: -0.5px;
    flex-shrink: 0; /* never squash the logo */
}

.nav-logo span {
    color: var(--accent);
}

/* Desktop nav links — horizontal */
.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.2s ease;
    white-space: nowrap;
}

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

/* Groups the dark toggle + hamburger on the right */
.nav-right {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    flex-shrink: 0;
}

/* ── Dark mode toggle ── */
.dark-toggle {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    cursor: pointer;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

.dark-toggle:hover {
    border-color: var(--accent);
    transform: scale(1.05);
}

/* =============================================
   HAMBURGER BUTTON
   Hidden on desktop. Three bars → X on open.
   ============================================= */
.hamburger {
    display: none; /* shown only on mobile via media query below */
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    width: 40px;
    height: 40px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    padding: 8px;
    transition: border-color 0.2s ease;
    flex-shrink: 0;
}

.hamburger:hover {
    border-color: var(--accent);
}

.hamburger .bar {
    display: block;
    width: 18px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: transform 0.3s ease, opacity 0.3s ease;
    transform-origin: center;
}

/* Animate bars into X shape when .hamburger--open is added by JS */
.hamburger--open .bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}
.hamburger--open .bar:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
}
.hamburger--open .bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* =============================================
   HERO SECTION
   ============================================= */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: var(--bg-primary);
    padding-top: 64px;
}

.hero-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 4rem 2rem;
    width: 100%;
}

.hero-badge {
    display: inline-block;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 0.4rem 1rem;
    border-radius: 100px;
    font-size: 0.85rem;
    margin-bottom: 1.5rem;
}

.hero-title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: clamp(2rem, 6vw, 5rem);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -1px;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.highlight {
    color: var(--accent);
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.3rem);
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    font-weight: 400;
}

.hero-location {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 2.5rem;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* =============================================
   BUTTONS
   ============================================= */
.btn {
    padding: 0.75rem 1.75rem;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s ease;
    display: inline-block;
    white-space: nowrap;
}

.btn-primary {
    background: var(--accent);
    color: #ffffff;
    border: 2px solid var(--accent);
}

.btn-primary:hover {
    background: var(--accent-hover);
    border-color: var(--accent-hover);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border);
}

.btn-secondary:hover {
    border-color: var(--accent);
    color: var(--accent);
    transform: translateY(-2px);
}

.btn-full {
    width: 100%;
    text-align: center;
}

/* =============================================
   FOOTER
   ============================================= */
.footer {
    text-align: center;
    padding: 2rem;
    color: var(--text-muted);
    font-size: 0.85rem;
    border-top: 1px solid var(--border);
}

/* =============================================
   SECTIONS — shared
   ============================================= */
.section-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 6rem 2rem;
    width: 100%;
}

.section-label {
    display: inline-block;
    color: var(--accent);
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 0.75rem;
}

.section-title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 3rem;
    letter-spacing: -0.5px;
    line-height: 1.2;
}

/* =============================================
   ABOUT SECTION
   ============================================= */
.about {
    background: var(--bg-secondary);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: start;
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
    font-size: 1rem;
    line-height: 1.8;
}

.about-stats {
    display: flex;
    gap: 2rem;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    flex-wrap: wrap;
}

.stat {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.stat-number {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--accent);
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.about-highlights {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.highlight-card {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.25rem;
    transition: border-color 0.2s ease, transform 0.2s ease;
}

.highlight-card:hover {
    border-color: var(--accent);
    transform: translateX(4px);
}

.highlight-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.highlight-card strong {
    display: block;
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 0.2rem;
}

.highlight-card p {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin: 0;
}

/* =============================================
   SKILLS SECTION
   ============================================= */
.skills {
    background: var(--bg-primary);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.skill-category {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.75rem;
    transition: border-color 0.2s ease, transform 0.2s ease;
}

.skill-category:hover {
    border-color: var(--accent);
    transform: translateY(-4px);
}

.skill-category-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skill-icon { font-size: 1.1rem; }

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

.tag {
    padding: 0.3rem 0.85rem;
    border-radius: 100px;
    font-size: 0.8rem;
    font-weight: 500;
}

.tag-purple { background: rgba(108, 59, 255, 0.12); color: var(--accent); }
.tag-teal   { background: rgba(20, 184, 166, 0.12); color: #0d9488; }
.tag-blue   { background: rgba(59, 130, 246, 0.12); color: #3b82f6; }
.tag-amber  { background: rgba(245, 158, 11, 0.12); color: #d97706; }
.tag-coral  { background: rgba(239, 68, 68, 0.12);  color: #ef4444; }
.tag-green  { background: rgba(34, 197, 94, 0.12);  color: #16a34a; }

html.dark .tag-teal  { color: #2dd4bf; }
html.dark .tag-blue  { color: #60a5fa; }
html.dark .tag-amber { color: #fbbf24; }
html.dark .tag-coral { color: #f87171; }
html.dark .tag-green { color: #4ade80; }

/* =============================================
   PROJECTS SECTION
   ============================================= */
.projects {
    background: var(--bg-secondary);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.project-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.75rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    transition: border-color 0.2s ease, transform 0.2s ease;
    position: relative;
    overflow: hidden;
}

.project-card:hover {
    border-color: var(--accent);
    transform: translateY(-6px);
}

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

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
}

.project-icon { font-size: 2rem; }

.project-links {
    display: flex;
    gap: 0.4rem;
    flex-wrap: wrap;
    justify-content: flex-end;
}

.project-tag {
    background: rgba(108, 59, 255, 0.1);
    color: var(--accent);
    padding: 0.2rem 0.6rem;
    border-radius: 100px;
    font-size: 0.75rem;
    font-weight: 500;
}

.project-title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.3;
}

.project-desc {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.7;
    flex: 1;
}

.project-footer {
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

.project-type {
    font-size: 0.8rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* =============================================
   CONTACT SECTION
   ============================================= */
.contact-section {
    background: var(--bg-secondary);
    min-height: 100vh;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.6fr;
    gap: 4rem;
    align-items: start;
}

.contact-intro {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 2rem;
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
}

.contact-icon {
    font-size: 1.25rem;
    margin-top: 2px;
    flex-shrink: 0;
}

.contact-label {
    display: block;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-muted);
    margin-bottom: 2px;
}

.contact-item a,
.contact-item span {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

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

.contact-form-wrapper {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 2.5rem;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.form-group label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input,
.form-group textarea,
.form-group select {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.75rem 1rem;
    color: var(--text-primary);
    font-size: 0.95rem;
    font-family: 'Inter', sans-serif;
    transition: border-color 0.2s ease;
    outline: none;
    width: 100%;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    border-color: var(--accent);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.input-error { border-color: #ef4444 !important; }
.field-error  { color: #ef4444; font-size: 0.8rem; }

.alert-success {
    background: rgba(34, 197, 94, 0.12);
    border: 1px solid rgba(34, 197, 94, 0.3);
    color: #16a34a;
    padding: 1rem 1.25rem;
    border-radius: 10px;
    margin-bottom: 2rem;
    font-size: 0.95rem;
}

html.dark .alert-success { color: #4ade80; }

/* =============================================
   AI CHAT WIDGET
   ============================================= */
.chat-widget {
    position: fixed;
    bottom: 1.5rem;
    right: 1.5rem;
    z-index: 999;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 1rem;
}

.chat-toggle-btn {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--accent);
    border: none;
    cursor: pointer;
    font-size: 1.4rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 20px rgba(108, 59, 255, 0.4);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    flex-shrink: 0;
}

.chat-toggle-btn:hover {
    transform: scale(1.08);
    box-shadow: 0 6px 28px rgba(108, 59, 255, 0.5);
}

.chat-window {
    width: 340px;
    height: 460px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 20px;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-shadow: var(--shadow);
    opacity: 0;
    transform: translateY(16px) scale(0.97);
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s ease;
}

.chat-window.chat-window--open {
    opacity: 1;
    transform: translateY(0) scale(1);
    pointer-events: all;
}

.chat-header {
    background: var(--accent);
    padding: 1rem 1.25rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-shrink: 0;
}

.chat-header-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.chat-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: 700;
    flex-shrink: 0;
}

.chat-name   { color: white; font-weight: 600; font-size: 0.9rem; }
.chat-status { color: rgba(255,255,255,0.8); font-size: 0.75rem; }

.chat-close {
    background: none;
    border: none;
    color: white;
    cursor: pointer;
    font-size: 1rem;
    opacity: 0.8;
    transition: opacity 0.2s;
    padding: 4px;
}
.chat-close:hover { opacity: 1; }

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 1.25rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.chat-message {
    max-width: 85%;
    padding: 0.65rem 0.9rem;
    border-radius: 12px;
    font-size: 0.875rem;
    line-height: 1.5;
}

.chat-message p { margin: 0; }

.chat-message--bot {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border);
    align-self: flex-start;
    border-bottom-left-radius: 4px;
}

.chat-message--user {
    background: var(--accent);
    color: white;
    align-self: flex-end;
    border-bottom-right-radius: 4px;
}

.chat-message--typing {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    align-self: flex-start;
    border-bottom-left-radius: 4px;
    color: var(--text-muted);
    font-style: italic;
}

.chat-input-area {
    padding: 1rem;
    border-top: 1px solid var(--border);
    display: flex;
    gap: 0.5rem;
    flex-shrink: 0;
}

.chat-input-area input {
    flex: 1;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.6rem 0.9rem;
    color: var(--text-primary);
    font-size: 0.875rem;
    font-family: 'Inter', sans-serif;
    outline: none;
    transition: border-color 0.2s ease;
    min-width: 0; /* prevents flex overflow */
}

.chat-input-area input:focus { border-color: var(--accent); }

.chat-send-btn {
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    width: 38px;
    height: 38px;
    cursor: pointer;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
    flex-shrink: 0;
}

.chat-send-btn:hover    { background: var(--accent-hover); }
.chat-send-btn:disabled { opacity: 0.5; cursor: not-allowed; }

/* =============================================
   RESPONSIVE — TABLET (max 900px)
   ============================================= */
@media (max-width: 900px) {
    .about-grid    { grid-template-columns: 1fr; gap: 2.5rem; }
    .contact-grid  { grid-template-columns: 1fr; gap: 2.5rem; }
    .section-container { padding: 4rem 1.5rem; }
}

/* =============================================
   RESPONSIVE — MOBILE (max 768px)
   ============================================= */
@media (max-width: 768px) {

    /* Show hamburger */
    .hamburger { display: flex; }

    .nav-container { padding: 0 1.25rem; }

    /*
        Mobile dropdown menu.
        We use max-height animation (0 → 320px) because
        you cannot transition display:none. overflow:hidden
        clips it when collapsed.
    */
    .nav-links {
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--nav-bg);
        backdrop-filter: blur(12px);
        border-bottom: 1px solid var(--border);
        flex-direction: column;
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.35s ease;
        z-index: 99;
    }

    .nav-links.nav-open { max-height: 320px; }

    .nav-links li { width: 100%; }

    .nav-links a {
        display: block;
        padding: 1rem 1.5rem;
        border-bottom: 1px solid var(--border);
        font-size: 1rem;
    }

    .nav-links li:last-child a { border-bottom: none; }

    .nav-links a:hover {
        background: var(--bg-secondary);
        color: var(--accent);
    }

    /* Hero */
    .hero-container  { padding: 3rem 1.25rem; }
    .hero-buttons    { flex-direction: column; align-items: stretch; }
    .hero-buttons .btn { width: 100%; text-align: center; }

    /* Sections */
    .section-container { padding: 3.5rem 1.25rem; }

    /* About */
    .about-grid  { grid-template-columns: 1fr; gap: 2rem; }
    .about-stats { gap: 1.25rem; }

    /* Skills & Projects */
    .skills-grid   { grid-template-columns: 1fr; }
    .projects-grid { grid-template-columns: 1fr; }

    /* Contact */
    .contact-grid         { grid-template-columns: 1fr; gap: 2rem; }
    .form-row             { grid-template-columns: 1fr; }
    .contact-form-wrapper { padding: 1.5rem; }

    /* Chat widget — fill most of screen width */
    .chat-widget  { bottom: 1rem; right: 1rem; }
    .chat-window  {
        width: calc(100vw - 2rem);
        max-width: 340px;
        height: 420px;
    }
}

/* =============================================
   RESPONSIVE — SMALL MOBILE (max 480px)
   ============================================= */
@media (max-width: 480px) {
    .hero-title    { font-size: clamp(1.8rem, 8vw, 2.5rem); letter-spacing: -0.5px; }
    .section-title { font-size: clamp(1.5rem, 6vw, 2rem); }
    .nav-logo      { font-size: 1.25rem; }
    .dark-toggle   { width: 36px; height: 36px; font-size: 1rem; }
    .stat-number   { font-size: 1.5rem; }

    .chat-window {
        width: calc(100vw - 1.5rem);
        height: 400px;
    }
}