/* =====================================================================
   PATRICK KIRUI - DEVELOPER PORTFOLIO DESIGN SYSTEM
   Modern, Authentic, High-Contrast UI/UX Architecture
   ===================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600&family=Material+Symbols+Outlined:opsz,wght,FILL,GRAD@20..48,100..700,0..1,-50..200&display=swap');

/* --- Root Color Tokens & Variables --- */
:root {
    /* Exact Pure Colors for Light Mode */
    --bg-page: #FFFFFF;
    --text-primary: #000000;
    --text-secondary: #4B5563;
    --text-muted: #6B7280;
    --surface-card: #FFFFFF;
    --surface-subtle: #F9FAFB;
    --surface-hover: #F3F4F6;
    --border-color: #E5E7EB;
    --border-subtle: #F0F2F5;
    
    /* Accents & Actions */
    --accent: #2563EB;
    --accent-hover: #1D4ED8;
    --accent-subtle: rgba(37, 99, 235, 0.08);
    --btn-primary-bg: #000000;
    --btn-primary-text: #FFFFFF;
    --btn-primary-hover: #1F2937;
    --btn-secondary-bg: #F3F4F6;
    --btn-secondary-text: #111827;
    --btn-secondary-border: #E5E7EB;
    --btn-secondary-hover: #E5E7EB;

    /* Status Colors */
    --success: #16A34A;
    --success-bg: #DCFCE7;
    --warning: #D97706;
    --warning-bg: #FEF3C7;
    --danger: #DC2626;
    --danger-bg: #FEE2E2;

    /* Typography & Sizing */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-full: 9999px;

    /* Transitions & Shadows */
    --transition-fast: 150ms cubic-bezier(0.16, 1, 0.3, 1);
    --transition-base: 250ms cubic-bezier(0.16, 1, 0.3, 1);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.08);
    --container-max: 1200px;
    --header-height: 72px;
}

/* Exact Pure Colors for Dark Mode */
[data-theme="dark"] {
    --bg-page: #000000;
    --text-primary: #FFFFFF;
    --text-secondary: #A1A1AA;
    --text-muted: #71717A;
    --surface-card: #09090B;
    --surface-subtle: #121214;
    --surface-hover: #18181B;
    --border-color: #27272A;
    --border-subtle: #1F1F23;

    --accent: #3B82F6;
    --accent-hover: #60A5FA;
    --accent-subtle: rgba(59, 130, 246, 0.12);
    --btn-primary-bg: #FFFFFF;
    --btn-primary-text: #000000;
    --btn-primary-hover: #E4E4E7;
    --btn-secondary-bg: #18181B;
    --btn-secondary-text: #FFFFFF;
    --btn-secondary-border: #27272A;
    --btn-secondary-hover: #27272A;

    --success: #22C55E;
    --success-bg: rgba(34, 197, 94, 0.15);
    --warning: #F59E0B;
    --warning-bg: rgba(245, 158, 11, 0.15);
    --danger: #EF4444;
    --danger-bg: rgba(239, 68, 68, 0.15);

    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.6);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.7);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
    color-scheme: light dark;
}

body {
    background-color: var(--bg-page);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background-color var(--transition-base), color var(--transition-base);
}

img, svg, picture {
    max-width: 100%;
    display: block;
}

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

button, input, select, textarea {
    font: inherit;
    color: inherit;
}

/* Material Symbols Icon helper */
.material-symbols-outlined {
    font-family: 'Material Symbols Outlined';
    font-weight: normal;
    font-style: normal;
    font-size: 20px;
    line-height: 1;
    letter-spacing: normal;
    text-transform: none;
    display: inline-block;
    white-space: nowrap;
    word-wrap: normal;
    direction: ltr;
    vertical-align: middle;
    user-select: none;
}

/* --- Container & Grid System --- */
.container,
.container.section {
    width: 100%;
    max-width: var(--container-max);
    margin-left: auto;
    margin-right: auto;
    padding-left: 1.5rem;
    padding-right: 1.5rem;
    box-sizing: border-box;
}

.container-narrow {
    width: 100%;
    max-width: 860px;
    margin-left: auto;
    margin-right: auto;
}

/* --- Navigation & Header --- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    height: var(--header-height);
    background-color: var(--bg-page);
    border-bottom: 1px solid var(--border-color);
    transition: background-color var(--transition-base), border-color var(--transition-base);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.brand-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 700;
    font-size: 1.15rem;
    letter-spacing: -0.02em;
}

.brand-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: var(--radius-sm);
    background-color: var(--btn-primary-bg);
    color: var(--btn-primary-text);
    font-size: 0.85rem;
    font-weight: 800;
    font-family: var(--font-mono);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    list-style: none;
}

.nav-link {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    padding: 0.4rem 0.6rem;
    border-radius: var(--radius-sm);
    position: relative;
    transition: color var(--transition-fast);
}

.nav-link:hover, .nav-link.active {
    color: var(--text-primary);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0.6rem;
    right: 0.6rem;
    height: 2px;
    background-color: var(--accent);
    border-radius: var(--radius-full);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* Theme Toggle Button */
.theme-toggle-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    cursor: pointer;
    transition: background-color var(--transition-fast), border-color var(--transition-fast), transform 150ms ease;
}

.theme-toggle-btn:hover {
    background-color: var(--surface-hover);
    transform: translateY(-1px);
}

.mobile-menu-btn {
    display: none;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    cursor: pointer;
}

/* --- Mobile Navigation Drawer --- */
.mobile-nav-drawer {
    display: none;
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--bg-page);
    border-top: 1px solid var(--border-color);
    padding: 2rem 1.5rem;
    z-index: 99;
    flex-direction: column;
    gap: 1.5rem;
    overflow-y: auto;
}

.mobile-nav-drawer.active {
    display: flex;
}

.mobile-nav-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.mobile-nav-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.85rem 1rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
}

/* --- Hero Section --- */
.hero-section {
    padding: 1.5rem 0 1rem;
    position: relative;
    border-bottom: 1px solid var(--border-subtle);
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.15fr 1fr;
    gap: 2.5rem;
    align-items: center;
}

.hero-text-col {
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.hero-tag {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.35rem 0.85rem;
    border-radius: var(--radius-full);
    background-color: var(--accent-subtle);
    border: 1px solid var(--accent);
    color: var(--accent);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.hero-tag .status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--success);
    box-shadow: 0 0 0 2px var(--success-bg);
}

.hero-title {
    font-size: clamp(2.4rem, 4.5vw, 3.5rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1.12;
    margin-bottom: 0.6rem;
    color: var(--text-primary);
}

.hero-headline {
    font-size: clamp(1.2rem, 2.2vw, 1.45rem);
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 0.85rem;
}

.hero-intro {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.65;
    margin-bottom: 1.35rem;
    max-width: 560px;
}

.hero-ctas {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.85rem;
    margin-bottom: 1.25rem;
}

.hero-meta-strip {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.75rem 1rem;
    font-size: 0.88rem;
    color: var(--text-muted);
}

.hero-meta-item {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.hero-meta-item .material-symbols-outlined {
    font-size: 1.05rem;
    color: var(--accent);
}

.hero-meta-divider {
    color: var(--border-color);
}

.hero-meta-link {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color var(--transition-fast);
}

.hero-meta-link .material-symbols-outlined {
    font-size: 0.95rem;
}

.hero-meta-link:hover {
    color: var(--accent);
}

/* Profile Photo / Avatar Presentation */
.hero-media-col {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
}

.profile-avatar-frame {
    width: 100%;
    max-width: 440px;
    margin: 0 auto;
    background: transparent !important;
    background-color: transparent !important;
    border: none !important;
    padding: 0;
    box-shadow: none !important;
    position: relative;
    overflow: visible;
    display: flex;
    align-items: center;
    justify-content: center;
}

.profile-avatar-img {
    width: auto;
    max-width: 100%;
    height: auto;
    max-height: 540px;
    object-fit: contain;
    border-radius: 0;
    display: block;
    transform: none;
    transition: transform var(--transition-base);
}

/* --- Buttons & UI Elements --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    border: 1px solid transparent;
    transition: all var(--transition-fast);
    text-decoration: none;
    line-height: 1;
    white-space: nowrap;
}

.btn:active {
    transform: scale(0.98);
}

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

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

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

.btn-secondary:hover {
    background-color: var(--btn-secondary-hover);
    color: var(--btn-secondary-text);
}

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

.btn-outline:hover {
    background-color: var(--surface-hover);
    border-color: var(--text-primary);
}

.btn-accent {
    background-color: var(--accent);
    color: #FFFFFF;
    border-color: var(--accent);
}

.btn-accent:hover {
    background-color: var(--accent-hover);
    color: #FFFFFF;
}

.btn-sm {
    padding: 0.5rem 0.9rem;
    font-size: 0.85rem;
    border-radius: var(--radius-sm);
}

.btn-lg {
    padding: 0.9rem 1.8rem;
    font-size: 1.05rem;
}

/* --- Section Headers --- */
.section-header {
    margin-bottom: 2.5rem;
}

.section-label {
    display: inline-block;
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.section-title {
    font-size: clamp(1.8rem, 3.5vw, 2.5rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
    max-width: 600px;
}

/* --- Section Container Vertical Spacing --- */
.section {
    padding-top: 3rem;
    padding-bottom: 3.5rem;
}

.hero-section + .section {
    padding-top: 2rem;
}

.section-subtle {
    background-color: var(--surface-subtle);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

/* --- Project Grid & Cards --- */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 2rem;
}

.project-card {
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast);
}

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

.project-card-media {
    width: 100%;
    aspect-ratio: 16 / 9;
    background-color: var(--surface-subtle);
    border-bottom: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.project-card-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-base);
}

.project-card:hover .project-card-img {
    transform: scale(1.03);
}

.project-media-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    color: var(--text-muted);
}

.project-card-content {
    padding: 1.75rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.project-meta-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 0.75rem;
}

.project-category-badge {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--accent);
}

.project-featured-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    font-size: 0.75rem;
    font-weight: 600;
    background-color: var(--accent-subtle);
    color: var(--accent);
    padding: 0.2rem 0.5rem;
    border-radius: var(--radius-full);
}

.project-card-title {
    font-size: 1.35rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
    line-height: 1.3;
}

.project-card-summary {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.project-tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 1.5rem;
}

.tech-tag {
    font-size: 0.8rem;
    font-weight: 500;
    font-family: var(--font-mono);
    padding: 0.25rem 0.6rem;
    border-radius: var(--radius-sm);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.project-card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.project-links-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.icon-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: var(--radius-sm);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.icon-btn:hover {
    color: var(--text-primary);
    border-color: var(--text-primary);
}

/* --- Project Filters & Search --- */
.filter-bar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 2.5rem;
    padding: 1.25rem;
    border-radius: var(--radius-lg);
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
}

.category-pills {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.pill-link {
    display: inline-block;
    padding: 0.45rem 1rem;
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    font-weight: 600;
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.pill-link:hover, .pill-link.active {
    background-color: var(--btn-primary-bg);
    color: var(--btn-primary-text);
    border-color: var(--btn-primary-bg);
}

.search-form {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    min-width: 260px;
}

.search-input {
    width: 100%;
    padding: 0.55rem 1rem;
    border-radius: var(--radius-md);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-size: 0.9rem;
    outline: none;
    transition: border-color var(--transition-fast);
}

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

/* --- Empty States --- */
.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    border-radius: var(--radius-lg);
    background-color: var(--surface-card);
    border: 1px dashed var(--border-color);
    max-width: 560px;
    margin: 2rem auto;
}

.empty-state-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    margin-bottom: 1.25rem;
}

.empty-state-icon .material-symbols-outlined {
    font-size: 32px;
}

.empty-state-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.empty-state-text {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

/* --- Skills Layout --- */
.skills-categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.75rem;
}

.skill-category-card {
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.75rem;
    transition: border-color var(--transition-fast);
}

.skill-category-card:hover {
    border-color: var(--accent);
}

.skill-category-title {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
}

.skill-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.45rem 0.85rem;
    border-radius: var(--radius-md);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-size: 0.85rem;
    font-weight: 600;
    font-family: var(--font-mono);
    transition: all var(--transition-fast);
}

.skill-badge:hover {
    background-color: var(--surface-hover);
    border-color: var(--text-primary);
}

/* --- Education Timeline --- */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    left: 20px;
    width: 2px;
    background-color: var(--border-color);
}

.timeline-item {
    position: relative;
    padding-left: 54px;
    margin-bottom: 2.5rem;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-marker {
    position: absolute;
    top: 4px;
    left: 11px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: var(--bg-page);
    border: 3px solid var(--accent);
    z-index: 2;
}

.timeline-card {
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.75rem;
    box-shadow: var(--shadow-sm);
}

.timeline-date {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 700;
    font-family: var(--font-mono);
    color: var(--accent);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
}

.timeline-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.timeline-subtitle {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.timeline-description {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.timeline-coursework {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px dashed var(--border-color);
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* --- Case Study Page --- */
.case-study-hero {
    padding: 4rem 0 3rem;
    border-bottom: 1px solid var(--border-color);
}

.case-study-meta-bar {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1.5rem;
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    margin: 2.5rem 0;
}

.case-meta-item .meta-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 700;
    color: var(--text-muted);
    margin-bottom: 0.25rem;
}

.case-meta-item .meta-val {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.case-study-body {
    padding: 3rem 0;
}

.case-study-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3.5rem;
}

.case-section {
    margin-bottom: 3rem;
}

.case-section-title {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.01em;
    color: var(--text-primary);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.case-text {
    font-size: 1.05rem;
    line-height: 1.75;
    color: var(--text-secondary);
    white-space: pre-line;
}

.case-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.gallery-thumbnail {
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--border-color);
    aspect-ratio: 16 / 10;
    cursor: pointer;
    background-color: var(--surface-subtle);
}

.gallery-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-fast);
}

.gallery-thumbnail:hover img {
    transform: scale(1.05);
}

/* --- Forms & Inputs --- */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.form-label .required {
    color: var(--danger);
}

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-size: 0.95rem;
    outline: none;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-control:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-subtle);
}

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

.form-hint {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 0.35rem;
}

/* --- Flash Messages & Alerts --- */
.alert {
    padding: 1rem 1.25rem;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    border: 1px solid transparent;
}

.alert-success {
    background-color: var(--success-bg);
    color: var(--success);
    border-color: var(--success);
}

.alert-error, .alert-danger {
    background-color: var(--danger-bg);
    color: var(--danger);
    border-color: var(--danger);
}

/* --- Pagination --- */
.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 3rem;
}

.page-item {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 0.5rem;
    border-radius: var(--radius-md);
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.page-item:hover, .page-item.active {
    background-color: var(--btn-primary-bg);
    color: var(--btn-primary-text);
    border-color: var(--btn-primary-bg);
}

.page-item.disabled {
    opacity: 0.4;
    pointer-events: none;
}

/* --- Footer --- */
.site-footer {
    margin-top: auto;
    background-color: var(--bg-page);
    border-top: 1px solid var(--border-color);
    padding: 3.5rem 0 2rem;
    transition: background-color var(--transition-base), border-color var(--transition-base);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 2.5rem;
}

.footer-brand .brand-logo {
    margin-bottom: 0.75rem;
}

.footer-desc {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
    max-width: 380px;
}

.footer-heading {
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.footer-link {
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* --- Page Components & Responsive Layout Grids --- */
.contact-layout-grid {
    display: grid;
    grid-template-columns: 1fr 1.6fr;
    gap: 2.5rem;
    align-items: flex-start;
}

.contact-info-card,
.contact-form-card {
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2.25rem;
    box-sizing: border-box;
}

.about-layout-grid {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
    align-items: flex-start;
    margin-bottom: 3.5rem;
}

.resume-banner-card {
    background-color: var(--surface-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2.25rem;
    box-shadow: var(--shadow-md);
    margin-bottom: 2.5rem;
    box-sizing: border-box;
}

.resume-preview-card {
    background-color: var(--surface-subtle);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-sizing: border-box;
}

/* --- Responsive Media Queries --- */
@media (max-width: 1024px) {
    .hero-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }

    .hero-intro {
        margin-left: auto;
        margin-right: auto;
    }

    .hero-ctas {
        justify-content: center;
    }

    .hero-meta-strip {
        justify-content: center;
    }

    .case-study-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .profile-avatar-frame {
        max-width: 380px;
    }

    .profile-avatar-img {
        max-height: 500px;
        transform: none;
    }

    .about-layout-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}

@media (max-width: 768px) {
    .container,
    .container.section {
        padding-left: 1.25rem;
        padding-right: 1.25rem;
    }

    .section {
        padding-top: 1.75rem;
        padding-bottom: 2.25rem;
    }

    .section-header {
        margin-bottom: 1.5rem;
    }

    .section-label {
        font-size: 0.8rem;
        margin-bottom: 0.35rem;
    }

    .section-title {
        font-size: clamp(1.6rem, 5vw, 2.1rem);
        line-height: 1.2;
    }

    .section-subtitle {
        font-size: 0.95rem;
        line-height: 1.55;
        margin-top: 0.35rem;
    }

    .nav-links {
        display: none;
    }

    .mobile-menu-btn {
        display: inline-flex;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .projects-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .filter-bar {
        flex-direction: column;
        align-items: stretch;
        gap: 1rem;
    }

    .search-form {
        width: 100%;
    }

    .contact-layout-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .contact-info-card,
    .contact-form-card {
        padding: 1.5rem;
    }

    .case-study-hero {
        padding: 2rem 0 1.5rem;
    }

    .case-study-meta-bar {
        grid-template-columns: 1fr 1fr;
        gap: 1rem;
        padding: 1rem;
        margin: 1.75rem 0;
    }

    .timeline::before {
        left: 12px;
    }

    .timeline-item {
        padding-left: 36px;
        margin-bottom: 1.75rem;
    }

    .timeline-marker {
        left: 3px;
        width: 18px;
        height: 18px;
        top: 5px;
        border-width: 2.5px;
    }

    .timeline-card {
        padding: 1.35rem 1.15rem;
        border-radius: var(--radius-md);
        width: 100%;
        box-sizing: border-box;
    }
}

@media (max-width: 640px) {
    .resume-banner-card {
        padding: 1.5rem 1.25rem;
    }

    .resume-preview-card {
        padding: 1.25rem;
    }

    .skill-category-card {
        padding: 1.25rem 1rem;
    }
}

@media (max-width: 480px) {
    .container,
    .container.section {
        padding-left: 1rem;
        padding-right: 1rem;
    }

    .section {
        padding-top: 1.25rem;
        padding-bottom: 1.75rem;
    }

    .section-header {
        margin-bottom: 1.25rem;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .section-subtitle {
        font-size: 0.9rem;
    }

    .hero-title {
        font-size: 2.1rem;
    }

    .btn {
        width: 100%;
    }

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

    .profile-avatar-frame {
        max-width: 280px;
    }

    .profile-avatar-img {
        max-height: 400px;
    }

    .timeline::before {
        left: 9px;
    }

    .timeline-item {
        padding-left: 28px;
        margin-bottom: 1.25rem;
    }

    .timeline-marker {
        left: 2px;
        width: 16px;
        height: 16px;
        top: 5px;
        border-width: 2.5px;
    }

    .timeline-card {
        padding: 1.15rem 0.9rem;
        border-radius: var(--radius-md);
    }

    .timeline-title {
        font-size: 1.15rem;
    }

    .timeline-subtitle {
        font-size: 0.92rem;
    }

    .timeline-date {
        font-size: 0.75rem;
    }

    .timeline-description {
        font-size: 0.88rem;
    }

    .timeline-coursework {
        font-size: 0.82rem;
        margin-top: 0.75rem;
        padding-top: 0.75rem;
    }

    .contact-info-card,
    .contact-form-card {
        padding: 1.25rem 1rem;
    }

    .case-study-hero {
        padding: 1.25rem 0 1rem;
    }

    .case-study-meta-bar {
        grid-template-columns: 1fr;
        padding: 0.85rem;
    }
}

/* Accessibility: Reduced Motion */
@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;
    }
}