/**
 * RailBud - Animations & Transitions
 * Smooth, buttery animations for delightful UX
 */

/* ========================================
   KEYFRAME ANIMATIONS
   ======================================== */

/* Fade In */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* Fade Out */
@keyframes fadeOut {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
    }
}

/* Slide Up */
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(1rem);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Slide Down */
@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-1rem);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Scale In */
@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* Spin */
@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

/* Pulse */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

/* Bounce */
@keyframes bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-4px);
    }
}

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

/* Train Move */
@keyframes trainMove {
    0%, 100% {
        transform: translateX(-20px);
    }
    50% {
        transform: translateX(20px);
    }
}

/* Track Scroll */
@keyframes trackScroll {
    from {
        transform: translateX(0);
    }
    to {
        transform: translateX(-50%);
    }
}

/* Toast In */
@keyframes toastIn {
    from {
        opacity: 0;
        transform: translateY(-100%);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Toast Out */
@keyframes toastOut {
    from {
        opacity: 1;
        transform: translateX(0);
    }
    to {
        opacity: 0;
        transform: translateX(100%);
    }
}

/* Modal Slide Up */
@keyframes modalSlideUp {
    from {
        opacity: 0;
        transform: translateY(100%);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* App Loader Fade */
@keyframes loaderFade {
    from {
        opacity: 1;
        visibility: visible;
    }
    to {
        opacity: 0;
        visibility: hidden;
    }
}

/* Progress Bar */
@keyframes progressBar {
    from {
        width: 0%;
    }
    to {
        width: 100%;
    }
}

/* ========================================
   ANIMATION CLASSES
   ======================================== */

.animate-fadeIn {
    animation: fadeIn var(--duration-normal) var(--ease-out);
}

.animate-slideUp {
    animation: slideUp var(--duration-normal) var(--ease-out);
}

.animate-slideDown {
    animation: slideDown var(--duration-normal) var(--ease-out);
}

.animate-scaleIn {
    animation: scaleIn var(--duration-normal) var(--ease-out);
}

.spin {
    animation: spin 1s linear infinite;
}

.pulse {
    animation: pulse 2s ease-in-out infinite;
}

.bounce {
    animation: bounce 1s ease-in-out infinite;
}

/* ========================================
   APP LOADER
   ======================================== */
.app-loader {
    position: fixed;
    inset: 0;
    background: var(--bg-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: var(--z-loader);
    transition: opacity var(--duration-slow) var(--ease-out),
                visibility var(--duration-slow) var(--ease-out);
}

.app-loader.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.loader-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-6);
}

.loader-icon {
    width: 3rem;
    height: 3rem;
    color: var(--color-primary-500);
    animation: bounce 1s ease-in-out infinite;
}

.loader-icon .train-icon {
    width: 100%;
    height: 100%;
}

.loader-track {
    width: 8rem;
    height: 4px;
    background: var(--surface-secondary);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.loader-progress {
    height: 100%;
    background: linear-gradient(90deg, var(--color-primary-500), var(--color-primary-400), var(--color-primary-500));
    background-size: 200% 100%;
    border-radius: var(--radius-full);
    animation: progressBar 1.5s ease-in-out infinite, shimmer 1.5s ease-in-out infinite;
}

/* ========================================
   LOADING STATE (Search Results)
   ======================================== */
.loading-visual {
    position: relative;
    height: 4rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-4);
}

.loading-train {
    position: relative;
    z-index: 2;
    color: var(--color-primary-500);
    animation: trainMove 2s ease-in-out infinite;
}

.loading-train [data-lucide] {
    width: 2.5rem;
    height: 2.5rem;
}

.loading-track {
    position: absolute;
    bottom: 0.5rem;
    left: 10%;
    right: 10%;
    height: 3px;
    background: repeating-linear-gradient(
        90deg,
        var(--border-primary) 0px,
        var(--border-primary) 10px,
        transparent 10px,
        transparent 20px
    );
    border-radius: var(--radius-full);
}

/* ========================================
   SKELETON LOADING
   ======================================== */
.skeleton-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    width: 100%;
    max-width: 20rem;
}

.skeleton-card {
    height: 5rem;
    background: linear-gradient(
        90deg,
        var(--skeleton-base) 0%,
        var(--skeleton-shine) 50%,
        var(--skeleton-base) 100%
    );
    background-size: 200% 100%;
    border-radius: var(--radius-lg);
    animation: shimmer 1.5s ease-in-out infinite;
}

.skeleton-card:nth-child(2) {
    animation-delay: 0.2s;
}

.skeleton-card:nth-child(3) {
    animation-delay: 0.4s;
}

/* ========================================
   STATE ICONS ANIMATION
   ======================================== */
.state-icon {
    width: 4rem;
    height: 4rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--surface-secondary);
    border-radius: var(--radius-full);
    margin-bottom: var(--space-4);
}

.state-icon [data-lucide] {
    width: 2rem;
    height: 2rem;
    color: var(--text-muted);
}

.state-icon-error {
    background: var(--color-error-50);
}

.state-icon-error [data-lucide] {
    color: var(--color-error-500);
}

.state-icon-warning {
    background: var(--color-warning-50);
}

.state-icon-warning [data-lucide] {
    color: var(--color-warning-500);
}

/* ========================================
   STATUS DOT
   ======================================== */
.status-dot {
    width: 6px;
    height: 6px;
    border-radius: var(--radius-full);
    background: var(--text-muted);
    transition: background var(--duration-normal);
}

.status-dot.online {
    background: var(--color-success-500);
    animation: pulse 2s ease-in-out infinite;
}

.status-dot.offline {
    background: var(--color-error-500);
}

.status-dot.checking {
    background: var(--color-warning-500);
    animation: pulse 1s ease-in-out infinite;
}

/* ========================================
   MODAL ANIMATIONS
   ======================================== */
.modal-overlay {
    animation: fadeIn var(--duration-normal) var(--ease-out);
}

.modal-overlay.hidden {
    animation: none;
}

.modal {
    animation: modalSlideUp var(--duration-slow) var(--ease-out);
}

/* ========================================
   ROUTE CARDS STAGGER
   ======================================== */
.route-list .route-card,
.route-list .alternate-card {
    animation: slideUp var(--duration-normal) var(--ease-out) both;
}

.route-list > :nth-child(1) { animation-delay: 0ms; }
.route-list > :nth-child(2) { animation-delay: 50ms; }
.route-list > :nth-child(3) { animation-delay: 100ms; }
.route-list > :nth-child(4) { animation-delay: 150ms; }
.route-list > :nth-child(5) { animation-delay: 200ms; }
.route-list > :nth-child(n+6) { animation-delay: 250ms; }

/* ========================================
   BUTTON RIPPLE EFFECT
   ======================================== */
.btn {
    position: relative;
    overflow: hidden;
}

.btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle, rgba(255,255,255,0.3) 0%, transparent 70%);
    transform: scale(0);
    opacity: 0;
    transition: transform 0.5s, opacity 0.3s;
}

.btn:active::after {
    transform: scale(2.5);
    opacity: 1;
    transition: transform 0s, opacity 0s;
}

/* ========================================
   INPUT FOCUS GLOW
   ======================================== */
.form-input {
    transition: border-color var(--duration-fast) var(--ease-default),
                box-shadow var(--duration-fast) var(--ease-default);
}

.form-input:focus {
    animation: none;
}

/* ========================================
   SWAP BUTTON ANIMATION
   ======================================== */
.swap-btn {
    transition: transform var(--duration-normal) var(--ease-bounce),
                background-color var(--duration-fast) var(--ease-default),
                box-shadow var(--duration-fast) var(--ease-default);
}

/* ========================================
   SMOOTH SECTION TRANSITIONS
   ======================================== */
.search-section,
.results-section,
.state-section {
    transition: opacity var(--duration-normal) var(--ease-default);
}

.state-section:not(.hidden) {
    animation: fadeIn var(--duration-normal) var(--ease-out);
}

/* ========================================
   TAB CONTENT TRANSITION
   ======================================== */
.tab-panel {
    opacity: 0;
    transform: translateY(8px);
    transition: opacity var(--duration-fast) var(--ease-out),
                transform var(--duration-fast) var(--ease-out);
}

.tab-panel.active {
    opacity: 1;
    transform: translateY(0);
}

/* ========================================
   SUGGESTIONS DROPDOWN ANIMATION
   ======================================== */
.suggestions {
    transition: opacity var(--duration-fast) var(--ease-out),
                transform var(--duration-fast) var(--ease-out),
                visibility var(--duration-fast);
}

.suggestion-item {
    transition: background-color var(--duration-fast) var(--ease-default);
}

/* ========================================
   REDUCED MOTION
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .spin {
        animation: none;
    }
    
    .pulse {
        animation: none;
    }
    
    .bounce {
        animation: none;
    }
}

/* ========================================
   CREDIT LINK HOVER
   ======================================== */
.credit-link {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    color: var(--text-link);
    font-weight: var(--font-medium);
    transition: color var(--duration-fast);
}

.credit-link::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    bottom: -2px;
    height: 1px;
    background: currentColor;
    transform: scaleX(0);
    transform-origin: right;
    transition: transform var(--duration-normal) var(--ease-out);
}

.credit-link:hover::after {
    transform: scaleX(1);
    transform-origin: left;
}

.credit-link [data-lucide] {
    width: 0.875rem;
    height: 0.875rem;
}