:root {
    --ivory: #f5f5f5;
    --paper: #f5f5f5;
    --charcoal: #0C2C55;
    --slate: #296374;
    --red-accent: #296374;
    --blue-accent: #0C2C55;
    --gold-accent: #629FAD;
    --olive: #296374;
    --warm-shadow: rgba(41, 99, 116, 0.12);
    --cool-shadow: rgba(12, 44, 85, 0.08);
    --font-heading: 'Epilogue', sans-serif;
    --font-body: 'Lora', serif;
    --easing: cubic-bezier(0.22, 1, 0.36, 1);
}

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

body {
    font-family: var(--font-body);
    background: var(--ivory);
    color: var(--charcoal);
    line-height: 1.75;
    overflow-x: hidden;
    position: relative;
    font-size: 17px;
    min-height: 100vh;
    animation: pageLoad 0.8s var(--easing);
}

@keyframes pageLoad {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* Selection styling */
::selection {
    background: var(--slate);
    color: white;
}

::-moz-selection {
    background: var(--slate);
    color: white;
}

/* Custom scrollbar */
::-webkit-scrollbar {
    width: 12px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--slate);
    border: 3px solid var(--paper);
}

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

/* Textured paper background with geometric overlay */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 30%, rgba(98, 159, 173, 0.04) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(12, 44, 85, 0.03) 0%, transparent 50%),
        repeating-linear-gradient(90deg, transparent, transparent 1px, rgba(12, 44, 85, 0.015) 1px, rgba(12, 44, 85, 0.015) 2px);
    z-index: -1;
    animation: subtleShift 40s ease-in-out infinite;
}

@keyframes subtleShift {
    0%, 100% { 
        transform: translateX(0) translateY(0); 
        opacity: 1;
    }
    50% { 
        transform: translateX(10px) translateY(-10px); 
        opacity: 0.9;
    }
}

/* Bauhaus-inspired geometric elements */
.geo-shape {
    position: fixed;
    opacity: 0.08;
    animation: constructivistFloat 25s ease-in-out infinite;
    z-index: 0;
    pointer-events: none;
}

.geo-shape:nth-child(1) {
    width: 220px;
    height: 4px;
    background: var(--slate);
    top: 15%;
    right: -110px;
    animation-delay: 0s;
    transform-origin: left center;
}

.geo-shape:nth-child(2) {
    width: 140px;
    height: 140px;
    border: 6px solid var(--blue-accent);
    border-radius: 50%;
    bottom: 20%;
    left: -70px;
    animation-delay: 5s;
    animation-duration: 30s;
}

.geo-shape:nth-child(3) {
    width: 0;
    height: 0;
    border-left: 90px solid transparent;
    border-right: 90px solid transparent;
    border-bottom: 156px solid var(--gold-accent);
    top: 50%;
    right: 5%;
    animation-delay: 10s;
    animation-duration: 35s;
}

@keyframes constructivistFloat {
    0%, 100% {
        transform: translate(0, 0) rotate(0deg);
        opacity: 0.08;
    }
    25% {
        transform: translate(40px, -20px) rotate(5deg);
        opacity: 0.12;
    }
    50% {
        transform: translate(80px, 0) rotate(10deg);
        opacity: 0.06;
    }
    75% {
        transform: translate(40px, 20px) rotate(5deg);
        opacity: 0.10;
    }
}

/* Reading progress indicator */
.scanline {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--slate) 0%, var(--blue-accent) 50%, var(--gold-accent) 100%);
    transform-origin: left;
    transform: scaleX(0);
    z-index: 1000;
    transition: transform 0.1s ease-out;
    pointer-events: none;
}

/* Header */
header {
    background: var(--paper);
    border-bottom: 3px solid var(--charcoal);
    padding: 3.5rem 2rem 2.5rem;
    text-align: center;
    position: relative;
    overflow: hidden;
    animation: slideDown 1s var(--easing);
}

header::after {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 0;
    width: 0;
    height: 3px;
    background: var(--slate);
    animation: underlineGrow 2s var(--easing) 0.5s forwards;
}

@keyframes underlineGrow {
    to {
        width: 35%;
    }
}

@keyframes slideDown {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    z-index: 10;
}

.system-status {
    font-family: var(--font-heading);
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.25em;
    color: var(--slate);
    opacity: 0.9;
    display: block;
    margin-bottom: 1.5rem;
    text-transform: uppercase;
}

h1 {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 8vw, 4.5rem);
    line-height: 1.1;
    margin: 0;
    font-weight: 900;
    letter-spacing: -0.03em;
    color: var(--charcoal);
    position: relative;
}

h1::before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    top: -15px;
    width: 8px;
    height: 8px;
    background: var(--slate);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

h1::after {
    content: '';
    position: absolute;
    bottom: -12px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--gold-accent);
    animation: titleUnderline 1.5s var(--easing) 0.8s forwards;
}

@keyframes titleUnderline {
    to {
        width: 40%;
    }
}

@keyframes pulse {
    0%, 100% {
        transform: translateX(-50%) scale(1);
        opacity: 1;
    }
    50% {
        transform: translateX(-50%) scale(1.4);
        opacity: 0.7;
    }
}

h1 .highlight {
    display: block;
    color: var(--slate);
    margin-top: 0.3rem;
}

.subtitle {
    font-family: var(--font-body);
    font-size: 1.05rem;
    color: var(--slate);
    margin-top: 2rem;
    letter-spacing: 0.02em;
    font-style: italic;
}

/* Search Section */
.search-section {
    padding: 4rem 2rem;
    display: flex;
    justify-content: center;
    animation: fadeInUp 1s var(--easing) 0.3s both;
    position: relative;
    z-index: 1;
}

@keyframes fadeInUp {
    from {
        transform: translateY(40px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.search-wrapper {
    position: relative;
    width: 100%;
    max-width: 800px;
}

.search-icon {
    position: absolute;
    left: 1.5rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--slate);
    font-weight: 700;
    font-family: var(--font-heading);
    font-size: 1.2rem;
}

#search-bar {
    width: 100%;
    background: white;
    border: 2px solid var(--charcoal);
    border-radius: 0;
    padding: 1.1rem 1.5rem 1.1rem 4rem;
    font-family: var(--font-body);
    font-size: 1rem;
    color: var(--charcoal);
    transition: all 0.2s var(--easing);
    letter-spacing: 0.01em;
    box-shadow: 4px 4px 0 rgba(41, 99, 116, 0.15);
}

#search-bar:focus {
    outline: none;
    border-color: var(--slate);
    box-shadow: 6px 6px 0 rgba(41, 99, 116, 0.25);
    transform: translate(-2px, -2px);
}

#search-bar::placeholder {
    color: var(--slate);
    font-family: var(--font-body);
    opacity: 0.6;
}

/* Grid */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem 5rem;
}

.presentations-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 2.5rem;
}

/* Cards */
.presentation-card {
    background: white;
    border: 2px solid var(--charcoal);
    border-radius: 0;
    position: relative;
    overflow: hidden;
    transition: all 0.2s var(--easing);
    opacity: 0;
    animation: cardFadeIn 1s var(--easing) forwards;
    box-shadow: 8px 8px 0 rgba(43, 45, 47, 0.06);
}

@keyframes cardFadeIn {
    from {
        opacity: 0;
        transform: translateY(40px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.presentation-card::before {
    content: '';
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    height: 6px;
    background: linear-gradient(90deg, var(--slate) 0%, var(--gold-accent) 50%, var(--blue-accent) 100%);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.6s var(--easing);
}

.presentation-card::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 0 0 40px 40px;
    border-color: transparent transparent var(--paper) transparent;
    transition: all 0.5s var(--easing);
    opacity: 0;
}

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

.presentation-card:hover::after {
    opacity: 1;
    border-width: 0 0 60px 60px;
}

.presentation-card:hover {
    transform: translate(-4px, -4px);
    box-shadow: 12px 12px 0 rgba(41, 99, 116, 0.2);
}

.image-container {
    width: 100%;
    height: 240px;
    overflow: hidden;
    position: relative;
    background: var(--paper);
    border-bottom: 2px solid var(--charcoal);
}

.image-container::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, transparent 0%, rgba(245, 245, 245, 0.3) 100%);
    pointer-events: none;
}

.presentation-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: grayscale(0%) contrast(1.05) brightness(0.95);
    transition: all 0.5s var(--easing);
}

.presentation-card:hover img {
    filter: grayscale(0%) contrast(1) brightness(1);
    transform: scale(1.05);
}

.card-content {
    padding: 1.8rem;
}

.card-number {
    font-family: var(--font-heading);
    color: var(--slate);
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    margin-bottom: 0.8rem;
    display: block;
    text-transform: uppercase;
}

.presentation-card h2 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    margin: 0 0 1rem;
    color: var(--charcoal);
    font-weight: 700;
    letter-spacing: -0.02em;
}

.presentation-card p {
    font-family: var(--font-body);
    color: var(--slate);
    font-size: 0.95rem;
    line-height: 1.75;
    margin-bottom: 1.5rem;
}

.card-action {
    display: flex;
    justify-content: flex-end;
}

.btn-glitch {
    position: relative;
    padding: 0.75rem 1.8rem;
    background: var(--slate);
    border: 2px solid var(--slate);
    border-radius: 0;
    color: white;
    text-decoration: none;
    font-family: var(--font-heading);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    transition: all 0.2s var(--easing);
    overflow: hidden;
    box-shadow: 4px 4px 0 rgba(41, 99, 116, 0.25);
}

.btn-glitch::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: var(--blue-accent);
    transition: left 0.2s var(--easing);
    z-index: -1;
}

.btn-glitch:hover::before {
    left: 0;
}

.btn-glitch:hover {
    transform: translate(-2px, -2px);
    box-shadow: 6px 6px 0 rgba(41, 99, 116, 0.35);
    border-color: var(--blue-accent);
}

/* Footer */
footer {
    background: var(--paper);
    border-top: 3px solid var(--charcoal);
    padding: 3rem 2rem;
    text-align: center;
    margin-top: 4rem;
    position: relative;
}

footer::before {
    content: '';
    position: absolute;
    top: -3px;
    left: 0;
    width: 40%;
    height: 3px;
    background: var(--gold-accent);
    animation: footerLine 2s var(--easing) 0.5s backwards;
}

@keyframes footerLine {
    from {
        width: 0;
    }
    to {
        width: 40%;
    }
}

footer::after {
    content: '';
    position: absolute;
    bottom: 0;
    right: 0;
    width: 60px;
    height: 60px;
    border-left: 3px solid var(--slate);
    border-top: 3px solid var(--slate);
    opacity: 0.3;
}

footer p {
    font-family: var(--font-heading);
    color: var(--slate);
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.02em;
    margin: 0;
}

@media (max-width: 768px) {
    body {
        font-size: 16px;
    }

    header {
        padding: 2.5rem 1.5rem 2rem;
    }

    h1 {
        font-size: 2.2rem;
    }

    h1::before {
        width: 6px;
        height: 6px;
        top: -12px;
    }

    h1::after {
        bottom: -10px;
    }

    .subtitle {
        font-size: 1rem;
        margin-top: 1.5rem;
    }

    .search-section {
        padding: 3rem 1.5rem;
    }

    .search-icon {
        left: 1rem;
        font-size: 1rem;
    }

    #search-bar {
        padding: 1rem 1rem 1rem 3rem;
        font-size: 0.95rem;
        box-shadow: 3px 3px 0 rgba(41, 99, 116, 0.15);
    }

    #search-bar:focus {
        box-shadow: 4px 4px 0 rgba(41, 99, 116, 0.25);
    }

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

    .container {
        padding: 0 1.5rem 3rem;
    }

    .presentation-card {
        box-shadow: 6px 6px 0 rgba(43, 45, 47, 0.06);
    }

    .presentation-card:hover {
        box-shadow: 8px 8px 0 rgba(41, 99, 116, 0.2);
    }

    .card-content {
        padding: 1.5rem;
    }

    .btn-glitch {
        padding: 0.7rem 1.5rem;
        font-size: 0.75rem;
        box-shadow: 3px 3px 0 rgba(41, 99, 116, 0.25);
    }

    .btn-glitch:hover {
        box-shadow: 4px 4px 0 rgba(41, 99, 116, 0.35);
    }

    footer {
        padding: 2rem 1.5rem;
    }

    footer::after {
        width: 50px;
        height: 50px;
    }
}