/**
 * Portfolio - Animation System
 * Modern scroll-triggered animations, section entrances, hover effects
 * CSS-only where possible, lightweight and performant
 * Load after style.css
 */

/* ========== Section Entrance Variants ========== */
/* Extends base anim-fade-up in style.css. Add: slide-left, slide-right, scale-in */

.anim-slide-left {
    opacity: 0;
    transform: translateX(60px);
    transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1), transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.anim-slide-left.anim-visible {
    opacity: 1;
    transform: translateX(0);
}

.anim-slide-right {
    opacity: 0;
    transform: translateX(-60px);
    transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1), transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.anim-slide-right.anim-visible {
    opacity: 1;
    transform: translateX(0);
}

.anim-scale-in {
    opacity: 0;
    transform: scale(0.9);
    transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1), transform 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.anim-scale-in.anim-visible {
    opacity: 1;
    transform: scale(1);
}

/* Stagger delays */
.anim-delay-1 { transition-delay: 0.1s; }
.anim-delay-2 { transition-delay: 0.2s; }
.anim-delay-3 { transition-delay: 0.3s; }
.anim-delay-4 { transition-delay: 0.4s; }
.anim-delay-5 { transition-delay: 0.5s; }

/* ========== Gradient Animated Text ========== */
.gradient-text {
    background: linear-gradient(90deg, var(--accent, #2563eb), var(--accent-green, #22c55e), var(--accent, #2563eb));
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 6s ease-in-out infinite;
}
@keyframes gradientShift {
    0%, 100% { background-position: 0% center; }
    50% { background-position: 100% center; }
}

/* ========== Word-by-Word Reveal (utility) ========== */
.word-reveal span {
    display: inline-block;
    opacity: 0;
    transform: translateY(12px);
    animation: wordReveal 0.5s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.word-reveal span:nth-child(1) { animation-delay: 0.1s; }
.word-reveal span:nth-child(2) { animation-delay: 0.15s; }
.word-reveal span:nth-child(3) { animation-delay: 0.2s; }
.word-reveal span:nth-child(4) { animation-delay: 0.25s; }
.word-reveal span:nth-child(5) { animation-delay: 0.3s; }
.word-reveal span:nth-child(6) { animation-delay: 0.35s; }
.word-reveal span:nth-child(7) { animation-delay: 0.4s; }
.word-reveal span:nth-child(8) { animation-delay: 0.45s; }
.word-reveal span:nth-child(9) { animation-delay: 0.5s; }
.word-reveal span:nth-child(10) { animation-delay: 0.55s; }
@keyframes wordReveal {
    to { opacity: 1; transform: translateY(0); }
}

/* ========== Typewriter Cursor ========== */
.typewriter-cursor {
    display: inline-block;
    width: 3px;
    height: 1em;
    background: var(--accent, #2563eb);
    margin-left: 2px;
    vertical-align: text-bottom;
    animation: blink 0.8s step-end infinite;
}
@keyframes blink {
    50% { opacity: 0; }
}

/* ========== Image Hover: 3D Tilt ========== */
.img-tilt-wrap {
    perspective: 1000px;
}
.img-tilt {
    transform-style: preserve-3d;
    transition: transform 0.4s cubic-bezier(0.23, 1, 0.32, 1);
}
.img-tilt:hover {
    transform: perspective(1000px) rotateX(2deg) rotateY(-4deg) scale(1.02);
}

/* ========== Image Hover: Overlay with Details ========== */
.img-overlay-wrap {
    position: relative;
    overflow: hidden;
}
.img-overlay-wrap .img-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(30, 41, 59, 0.9) 0%, rgba(30, 41, 59, 0.4) 50%, transparent);
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 1.5rem;
    opacity: 0;
    transition: opacity 0.4s ease;
}
.img-overlay-wrap:hover .img-overlay {
    opacity: 1;
}
.img-overlay-wrap .img-overlay * {
    color: #fff;
    transform: translateY(12px);
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.img-overlay-wrap:hover .img-overlay * {
    transform: translateY(0);
}
.project-overlay-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}
.project-overlay-link {
    font-weight: 600;
    opacity: 0.9;
    text-decoration: underline;
    transition: opacity 0.2s ease;
}
.project-overlay-link:hover {
    opacity: 1;
}

/* ========== Animated Border (gradient border effect) ========== */
.border-animated {
    position: relative;
    border-radius: var(--radius-lg, 12px);
}
.border-animated::before {
    content: '';
    position: absolute;
    inset: -2px;
    border-radius: inherit;
    padding: 2px;
    background: linear-gradient(135deg, var(--accent), var(--accent-green), var(--accent));
    background-size: 200% 200%;
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    opacity: 0;
    transition: opacity 0.4s ease;
    animation: borderGradient 3s ease infinite;
}
.border-animated:hover::before {
    opacity: 1;
}
@keyframes borderGradient {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

/* ========== Card Glow on Hover ========== */
.card-glow {
    position: relative;
}
.card-glow::after {
    content: '';
    position: absolute;
    inset: -1px;
    border-radius: inherit;
    background: radial-gradient(circle at 50% 50%, rgba(37, 99, 235, 0.15), transparent 70%);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.4s ease;
}
.card-glow:hover::after {
    opacity: 1;
}

/* ========== Button Ripple Container ========== */
.btn-ripple {
    position: relative;
    overflow: hidden;
}
.btn-ripple .ripple {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.4);
    transform: scale(0);
    animation: rippleAnim 0.6s ease-out;
    pointer-events: none;
}
@keyframes rippleAnim {
    to {
        transform: scale(4);
        opacity: 0;
    }
}

/* ========== Touch: Disable 3D tilt on mobile (performance) ========== */
@media (hover: none) {
    .img-tilt:hover { transform: none; }
}

/* ========== Button Gradient Hover ========== */
.btn-gradient {
    background: linear-gradient(135deg, var(--accent), #1d4ed8);
    background-size: 200% 200%;
    transition: background-position 0.4s ease, transform 0.3s ease, box-shadow 0.3s ease;
}
.btn-gradient:hover {
    background-position: 100% 0;
    box-shadow: 0 8px 32px rgba(37, 99, 235, 0.4);
    transform: translateY(-2px);
}