/* ============================================
   SCROLL PROGRESS BAR
   ============================================ */
#scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    width: 0%;
    background: linear-gradient(to right, #3b82f6, #10b981);
    z-index: 9999;
    transition: width 0.1s linear;
    box-shadow: 0 0 8px rgba(59, 130, 246, 0.7);
}

/* ============================================
   HERO SECTION — PARTICLE CANVAS
   ============================================ */
#particle-canvas {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* ============================================
   HERO BACKGROUND ORB
   ============================================ */
.background-orb {
    position: absolute;
    width: 700px;
    height: 700px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.18) 0%, rgba(15, 23, 42, 0) 70%);
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 1;
    animation: float 10s ease-in-out infinite;
    pointer-events: none;
}

@keyframes float {
    0%   { transform: translate(-50%, -50%) scale(1); }
    50%  { transform: translate(-50%, -60%) scale(1.12); }
    100% { transform: translate(-50%, -50%) scale(1); }
}

/* ============================================
   HERO TITLE — SLIDE IN FROM LEFT
   ============================================ */
.hero-title {
    animation: slideInLeft 0.9s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.hero-subtitle {
    animation: slideInLeft 0.9s 0.2s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.hero-section .btn {
    animation: slideInLeft 0.9s 0.4s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-40px); }
    to   { opacity: 1; transform: translateX(0); }
}

/* ============================================
   TYPEWRITER BLINKING CURSOR
   ============================================ */
.cursor-blink {
    display: inline-block;
    color: var(--primary-color);
    font-weight: 300;
    animation: blink 0.8s step-end infinite;
    margin-left: 2px;
}

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

/* ============================================
   HERO CTA BUTTON — PULSE GLOW
   ============================================ */
.btn-primary {
    animation: pulse-glow 2.5s 1.5s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% { box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4); }
    50%       { box-shadow: 0 4px 30px rgba(59, 130, 246, 0.8), 0 0 0 6px rgba(59, 130, 246, 0.15); }
}

/* ============================================
   NAVBAR — ACTIVE LINK
   ============================================ */
.nav-links a.active {
    color: var(--primary-color);
    position: relative;
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(to right, #3b82f6, #10b981);
    border-radius: 2px;
    animation: slideInWidth 0.3s ease forwards;
}

@keyframes slideInWidth {
    from { width: 0; }
    to   { width: 100%; }
}

/* ============================================
   NAVBAR — SHRINK ON SCROLL
   ============================================ */
.navbar.scrolled {
    padding: 0.5rem 5%;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    transition: padding 0.3s ease, box-shadow 0.3s ease;
}

/* ============================================
   SCROLL FADE IN (triggered by JS)
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in.appear {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   SECTION TITLES — UNDERLINE GROW ON APPEAR
   ============================================ */
.section-title {
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 3px;
    background: linear-gradient(to right, #3b82f6, #10b981);
    border-radius: 2px;
    transition: width 0.6s ease;
}

.section.appear .section-title::after,
.dark-bg.appear .section-title::after {
    width: 60px;
}

/* ============================================
   SKILL CARDS — FLIP ON HOVER
   ============================================ */
.skill-card {
    perspective: 600px;
}

.skill-card:hover .skill-icon {
    animation: iconSpin 0.5s ease;
}

@keyframes iconSpin {
    0%   { transform: rotateY(0deg) scale(1); }
    50%  { transform: rotateY(90deg) scale(1.2); }
    100% { transform: rotateY(0deg) scale(1); }
}

/* ============================================
   PROJECT CARDS — 3D TILT (enhanced by JS)
   ============================================ */
.project-card {
    transform-style: preserve-3d;
    will-change: transform;
}

/* ============================================
   LOGO — COLOR SHIMMER
   ============================================ */
.logo {
    background: linear-gradient(90deg, #f8fafc, #3b82f6, #10b981, #f8fafc);
    background-size: 300%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: shimmer 4s linear infinite;
}

@keyframes shimmer {
    0%   { background-position: 0% center; }
    100% { background-position: 300% center; }
}

/* ============================================
   SECTION ENTRY — SLIDE UP (staggered children)
   ============================================ */
@keyframes slideUp {
    from { opacity: 0; transform: translateY(50px); }
    to   { opacity: 1; transform: translateY(0); }
}