/* ═══════════════════════════════════════════════════════════════════════════════
   JAVASCRIPT PROJECTS - STYLESHEET
   ═══════════════════════════════════════════════════════════════════════════════ */

/* ── Root Variables & Theme ── */
:root {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --accent: #06b6d4;
    --accent-hover: #0891b2;
    --success: #22c55e;
    --warning: #f59e0b;
    --danger: #ef4444;
    --border: #475569;

    --easy: #10b981;
    --medium: #f59e0b;
    --intermediate: #8b5cf6;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 48px rgba(0, 0, 0, 0.6);

    --transition-fast: 0.15s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.6s ease;
}

/* Light Theme */
html.light-theme {
    --bg-primary: #f8fafc;
    --bg-secondary: #f1f5f9;
    --bg-tertiary: #e2e8f0;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --accent: #0891b2;
    --accent-hover: #06b6d4;
    --border: #cbd5e1;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 48px rgba(0, 0, 0, 0.2);
}

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

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
        'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
        sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color var(--transition-slow),
                color var(--transition-slow);
}

/* ── Page Wrapper ── */
.page-wrapper {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    position: relative;
    overflow-x: hidden;
}

/* ── Navigation ── */
.navbar {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background-color: rgba(30, 41, 59, 0.8);
    box-shadow: var(--shadow-md);
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    gap: 2rem;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--accent) 0%, #06b6d4 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    min-width: -webkit-fill-available;
    min-width: fit-content;
}

.nav-title {
    flex: 1;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.back-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: 0.5rem;
    transition: all var(--transition-base);
    background: rgba(6, 182, 212, 0.1);
}

.back-link:hover {
    color: var(--accent);
    background: rgba(6, 182, 212, 0.2);
    transform: translateX(-2px);
}

.back-link svg {
    transition: transform var(--transition-base);
}

.back-link:hover svg {
    transform: translateX(-3px);
}

@media (max-width: 768px) {
    .nav-inner {
        padding: 0 1rem;
        gap: 1rem;
    }

    .nav-title {
        display: none;
    }
}

/* ── Page Header ── */
.page-header {
    max-width: 1400px;
    margin: 0 auto;
    padding: 4rem 2rem;
    text-align: center;
}

.page-header h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
    margin-bottom: 1rem;
    line-height: 1.2;
    color: var(--text-primary);
}

.page-header .highlight {
    background: linear-gradient(135deg, var(--accent) 0%, #06b6d4 50%, var(--success) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
}

.page-header p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

@media (max-width: 768px) {
    .page-header {
        padding: 2rem 1rem;
    }
}

/* ── Main Container ── */
.main-container {
    flex: 1;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
    padding: 0 2rem 2rem;
}

.projects-main {
    width: 100%;
}

/* ── Project Section ── */
.project-section {
    margin-bottom: 4rem;
    opacity: 0;
    transform: translateY(20px);
}

.section-header {
    margin-bottom: 2rem;
}

.section-header h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.section-header p {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* ── Projects Grid ── */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
    width: 100%;
}

@media (max-width: 1024px) {
    .projects-grid {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 1.5rem;
    }
}

@media (max-width: 640px) {
    .projects-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
}

/* ── Project Card ── */
.project-card {
    perspective: 1000px;
    height: 320px;
    cursor: pointer;
    border-radius: 0.75rem;
    overflow: hidden;
    outline: none;
}

.project-card:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.card-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform var(--transition-slow);
    transform-style: preserve-3d;
}

.project-card.flipped .card-inner {
    transform: rotateY(180deg);
}

/* ── Card Front ── */
.card-front,
.card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    border-radius: 0.75rem;
    transition: all var(--transition-base);
}

.card-front {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    border: 1px solid var(--border);
    gap: 1rem;
    text-align: center;
}

.project-card:hover:not(.flipped) .card-front {
    background: linear-gradient(135deg, var(--bg-tertiary) 0%, var(--bg-secondary) 100%);
    border-color: var(--accent);
    box-shadow: var(--shadow-lg), 0 0 20px rgba(6, 182, 212, 0.2);
    transform: translateY(-4px);
}

.card-icon {
    font-size: 3.5rem;
    line-height: 1;
}

.card-front h3 {
    font-size: 1.5rem;
    color: var(--text-primary);
}

.difficulty {
    display: inline-block;
    padding: 0.375rem 1rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.difficulty.easy {
    background: rgba(16, 185, 129, 0.15);
    color: var(--easy);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.difficulty.medium {
    background: rgba(245, 158, 11, 0.15);
    color: var(--medium);
    border: 1px solid rgba(245, 158, 11, 0.3);
}

.difficulty.intermediate {
    background: rgba(139, 92, 246, 0.15);
    color: var(--intermediate);
    border: 1px solid rgba(139, 92, 246, 0.3);
}

/* ── Card Back ── */
.card-back {
    background: linear-gradient(135deg, rgba(6, 182, 212, 0.1) 0%, rgba(139, 92, 246, 0.1) 100%),
                var(--bg-secondary);
    border: 1px solid var(--accent);
    gap: 1rem;
    padding: 1.5rem;
    transform: rotateY(180deg);
    text-align: left;
    justify-content: flex-start;
    overflow-y: auto;
}

.card-back h3 {
    font-size: 1.25rem;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.card-back p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 0.5rem;
}

.card-back p strong {
    color: var(--accent);
    display: block;
    margin-bottom: 0.25rem;
}

.start-btn {
    display: inline-block;
    margin-top: auto;
    padding: 0.75rem 1.25rem;
    background: linear-gradient(135deg, var(--accent) 0%, #0891b2 100%);
    color: white;
    text-decoration: none;
    border-radius: 0.5rem;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all var(--transition-base);
    border: none;
    cursor: pointer;
    white-space: nowrap;
}

.start-btn:hover {
    background: linear-gradient(135deg, var(--accent-hover) 0%, #0e7490 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.start-btn:active {
    transform: translateY(0);
}

/* ── Animations ── */
@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes glow {
    0%, 100% {
        box-shadow: 0 0 10px rgba(6, 182, 212, 0.3);
    }
    50% {
        box-shadow: 0 0 20px rgba(6, 182, 212, 0.6);
    }
}

/* ── Page Footer ── */
.page-footer {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    border-top: 1px solid var(--border);
    padding: 2rem;
    margin-top: 4rem;
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1400px;
    margin: 0 auto;
    gap: 2rem;
}

.footer-inner span {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.footer-link {
    color: var(--accent);
    text-decoration: none;
    transition: all var(--transition-base);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    background: rgba(6, 182, 212, 0.1);
}

.footer-link:hover {
    color: var(--accent-hover);
    background: rgba(6, 182, 212, 0.2);
    transform: translateX(2px);
}

@media (max-width: 640px) {
    .footer-inner {
        flex-direction: column;
        text-align: center;
    }
}

/* ── Responsive Design ── */
@media (max-width: 768px) {
    .main-container {
        padding: 0 1rem 1rem;
    }

    .section-header h2 {
        font-size: 1.5rem;
    }

    .project-card {
        height: 280px;
    }

    .card-front,
    .card-back {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .projects-grid {
        grid-template-columns: 1fr;
    }

    .card-front h3 {
        font-size: 1.25rem;
    }

    .card-icon {
        font-size: 2.5rem;
    }
}

/* ── Scrollbar Styling ── */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--accent);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-hover);
}

/* ── Selection ── */
::selection {
    background: var(--accent);
    color: white;
}

/* ── Featured Section ── */
.featured-section {
    background: linear-gradient(135deg, rgba(6, 182, 212, 0.1) 0%, rgba(139, 92, 246, 0.1) 100%);
    border: 1px solid rgba(6, 182, 212, 0.3);
    border-radius: 1rem;
    padding: 3rem 2rem;
    margin-bottom: 4rem;
}

.featured-content {
    text-align: center;
    width: 100%;
}

.featured-box {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
    border: 1px solid var(--accent);
    border-radius: 0.75rem;
    padding: 2.5rem;
    max-width: 700px;
    margin: 0 auto;
    box-shadow: var(--shadow-md), 0 0 30px rgba(6, 182, 212, 0.15);
    transition: all var(--transition-base);
}

.featured-box:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg), 0 0 40px rgba(6, 182, 212, 0.25);
    border-color: var(--accent-hover);
}

.featured-text {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.featured-btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    background: linear-gradient(135deg, var(--accent) 0%, #0891b2 100%);
    color: white;
    text-decoration: none;
    border-radius: 0.5rem;
    font-weight: 600;
    font-size: 1rem;
    transition: all var(--transition-base);
    border: none;
    cursor: pointer;
    white-space: nowrap;
    box-shadow: var(--shadow-md);
}

.featured-btn:hover {
    background: linear-gradient(135deg, var(--accent-hover) 0%, #0e7490 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 20px rgba(6, 182, 212, 0.4);
}

.featured-btn:active {
    transform: translateY(0);
}

@media (max-width: 768px) {
    .featured-section {
        padding: 2rem 1rem;
        margin-bottom: 3rem;
    }

    .featured-box {
        padding: 1.5rem;
    }

    .featured-text {
        font-size: 1rem;
    }

    .featured-btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.95rem;
    }
}

/* ── Accessibility ── */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}


/* ── Print Styles ── */
@media print {
    .navbar,
    .page-footer {
        display: none;
    }

    .card-back {
        display: block !important;
        transform: none;
    }
}