/* ========================================
   ADVANCED ANIMATION SYSTEM
   Modern web design patterns
   ======================================== */

/* ========================================
   1. INITIAL STATE & PRELOADER
   ======================================== */

/* Prevent scroll during load */
html.no-scroll {
    overflow: hidden !important;
    height: 100vh;
}

html.loading body {
    overflow: hidden;
}

/* Ensure scroll works after loading */
html.loaded {
    overflow: auto !important;
    height: auto;
}

html.loaded body {
    overflow: auto;
}

/* Preloader */
#page-preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    z-index: 99999;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 32px;
    opacity: 1;
    transition: opacity 0.8s cubic-bezier(0.4, 0.0, 0.2, 1);
}

#page-preloader.hidden {
    opacity: 0;
    pointer-events: none;
}

.preloader-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
}

.preloader-logo {
    width: 80px;
    height: 80px;
    position: relative;
    animation: pulse 2s cubic-bezier(0.4, 0.0, 0.2, 1) infinite;
}

.preloader-logo img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.preloader-text {
    font-size: 14px;
    font-weight: 500;
    color: rgba(0, 0, 0, 0.6);
    letter-spacing: 0.5px;
    animation: fadeInOut 2s ease-in-out infinite;
}

.preloader-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid rgba(0, 0, 0, 0.1);
    border-top-color: rgba(0, 0, 0, 0.6);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        opacity: 1;
    }
    50% {
        transform: scale(1.05);
        opacity: 0.8;
    }
}

@keyframes fadeInOut {
    0%, 100% {
        opacity: 0.4;
    }
    50% {
        opacity: 1;
    }
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* ========================================
   2. TEXT REVEAL ANIMATIONS
   ======================================== */

/* Text masking technique */
.text-reveal {
    display: inline-block;
    overflow: hidden;
}

.text-reveal-inner {
    display: inline-block;
    transform: translateY(120%);
    transition: transform 0.8s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.revealed .text-reveal-inner {
    transform: translateY(0);
}

/* Character by character reveal */
.char-reveal {
    display: inline-block;
    transform: translateY(100%);
    opacity: 0;
}

/* ========================================
   3. ELEMENT REVEAL SYSTEM
   ======================================== */

/* Base reveal state */
[data-reveal] {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s cubic-bezier(0.4, 0.0, 0.2, 1),
                transform 0.8s cubic-bezier(0.4, 0.0, 0.2, 1);
}

[data-reveal].revealed {
    opacity: 1;
    transform: translateY(0);
}

/* Reveal from bottom */
[data-reveal="bottom"] {
    opacity: 0;
    transform: translateY(60px);
}

[data-reveal="bottom"].revealed {
    opacity: 1;
    transform: translateY(0);
}

/* Reveal from top */
[data-reveal="top"] {
    opacity: 0;
    transform: translateY(-40px);
}

[data-reveal="top"].revealed {
    opacity: 1;
    transform: translateY(0);
}

/* Reveal fade only */
[data-reveal="fade"] {
    opacity: 0;
    transform: none;
}

[data-reveal="fade"].revealed {
    opacity: 1;
}

/* Reveal scale */
[data-reveal="scale"] {
    opacity: 0;
    transform: scale(0.95);
}

[data-reveal="scale"].revealed {
    opacity: 1;
    transform: scale(1);
}

/* ========================================
   4. SECTION ANIMATIONS
   ======================================== */

.main_page {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 1s cubic-bezier(0.4, 0.0, 0.2, 1),
                transform 1s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.main_page.revealed {
    opacity: 1;
    transform: translateY(0);
}

/* ========================================
   5. HEADER ANIMATIONS
   ======================================== */

.header {
    opacity: 1;
}

.header_icon,
.nav_item {
    transform: translateY(0);
    transition: all 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.nav_item:hover {
    transform: translateY(-2px);
    opacity: 0.7;
}

/* ========================================
   6. PAGE INDICATOR
   ======================================== */

.page-indicator {
    opacity: 0;
    transform: translateX(20px);
    transition: all 0.8s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.page-indicator.revealed {
    opacity: 1;
    transform: translateX(0);
}

/* ========================================
   7. PAGE TRANSITION OVERLAY
   ======================================== */

html.page-transitioning::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    z-index: 99998;
    opacity: 0;
    animation: transitionIn 0.6s cubic-bezier(0.4, 0.0, 0.2, 1) forwards;
    pointer-events: none;
}

@keyframes transitionIn {
    to {
        opacity: 1;
    }
}

/* ========================================
   8. MICRO-INTERACTIONS
   ======================================== */

/* Slideshow dots */
.slideshow-dot {
    transition: all 0.4s cubic-bezier(0.4, 0.0, 0.2, 1);
    cursor: pointer;
    position: relative;
}

.slideshow-dot::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transition: all 0.4s cubic-bezier(0.4, 0.0, 0.2, 1);
    z-index: -1;
}

.slideshow-dot:hover::before {
    transform: translate(-50%, -50%) scale(1);
}

.slideshow-dot:hover {
    transform: scale(1.4);
}

.slideshow-dot:active {
    transform: scale(0.9);
}

/* Smooth hover effects */
.hover_dim {
    transition: opacity 0.3s cubic-bezier(0.4, 0.0, 0.2, 1),
                transform 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
}

.hover_dim:hover {
    opacity: 0.7;
}

/* ========================================
   9. IMAGE LOADING STATES
   ======================================== */

img:not([src]) {
    background: linear-gradient(
        90deg,
        rgba(0, 0, 0, 0.05) 0%,
        rgba(0, 0, 0, 0.08) 50%,
        rgba(0, 0, 0, 0.05) 100%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s ease-in-out infinite;
}

@keyframes shimmer {
    0% {
        background-position: -200% 0;
    }
    100% {
        background-position: 200% 0;
    }
}

/* ========================================
   10. SMOOTH SCROLLING
   ======================================== */

html {
    scroll-behavior: smooth;
}

/* Custom scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.02);
}

::-webkit-scrollbar-thumb {
    background: rgba(0, 0, 0, 0.15);
    border-radius: 4px;
    transition: background 0.3s ease;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(0, 0, 0, 0.25);
}

/* ========================================
   11. FOCUS STATES
   ======================================== */

a:focus-visible,
button:focus-visible {
    outline: 2px solid rgba(0, 0, 0, 0.3);
    outline-offset: 4px;
    border-radius: 4px;
}

/* ========================================
   12. PERFORMANCE OPTIMIZATIONS
   ======================================== */

.will-animate {
    will-change: transform, opacity;
}

/* Remove will-change after animation */
.revealed {
    will-change: auto;
}

/* ========================================
   13. REDUCED MOTION
   ======================================== */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    [data-reveal],
    .main_page,
    .text-reveal-inner {
        opacity: 1 !important;
        transform: none !important;
    }
}

/* ========================================
   14. RESPONSIVE ANIMATIONS
   ======================================== */

@media (max-width: 768px) {
    [data-reveal] {
        transform: translateY(20px);
    }
    
    .main_page {
        transform: translateY(15px);
    }
}

/* ========================================
   15. PUBLICATIONS YEAR NAVIGATION
   ======================================== */

.active-year {
    color: #3b82f6 !important; /* Blue highlight */
    font-weight: 700 !important;
    transform: scale(1.15);
    transition: all 0.4s cubic-bezier(0.4, 0.0, 0.2, 1);
}

/* Smooth transition for non-active years */
[id^="year_"] {
    transition: all 0.4s cubic-bezier(0.4, 0.0, 0.2, 1);
}

/* ========================================
   16. NAVIGATION HOVER EFFECTS
   ======================================== */

.nav_item {
    position: relative;
    padding-bottom: 4px;
    transition: all 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
}

/* Expanding bar underneath */
.nav_item::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0%;
    height: 2px;
    background: linear-gradient(90deg, #3b82f6, #60a5fa);
    transform: translateX(-50%);
    transition: width 0.4s cubic-bezier(0.4, 0.0, 0.2, 1);
    opacity: 0;
}

/* Hover state */
.nav_item:hover {
    color: #3b82f6 !important;
    transform: translateY(-2px);
}

.nav_item:hover::after {
    width: 100%;
    opacity: 1;
}

/* Active page indicator */
.nav_item.active {
    color: #3b82f6 !important;
}

.nav_item.active::after {
    width: 100%;
    opacity: 1;
}

/* Smooth color transition */
.nav_item,
.nav_item i {
    transition: all 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
}

/* Icon hover effect */
.nav_item:hover i {
    color: #3b82f6;
    transform: scale(1.1);
}