/* ============================================
   Frontalier Malin — Shared Styles & Animations
   ============================================ */

/* --- Scroll Animations --- */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1),
                transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}

.animate-on-scroll.is-visible {
    opacity: 1;
    transform: translateY(0);
}

.animate-fade-left {
    opacity: 0;
    transform: translateX(-30px);
    transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1),
                transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}

.animate-fade-left.is-visible {
    opacity: 1;
    transform: translateX(0);
}

.animate-fade-right {
    opacity: 0;
    transform: translateX(30px);
    transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1),
                transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}

.animate-fade-right.is-visible {
    opacity: 1;
    transform: translateX(0);
}

.animate-scale {
    opacity: 0;
    transform: scale(0.92);
    transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1),
                transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}

.animate-scale.is-visible {
    opacity: 1;
    transform: scale(1);
}

/* Stagger children */
.stagger-children > *:nth-child(1) { transition-delay: 0ms; }
.stagger-children > *:nth-child(2) { transition-delay: 100ms; }
.stagger-children > *:nth-child(3) { transition-delay: 200ms; }
.stagger-children > *:nth-child(4) { transition-delay: 300ms; }
.stagger-children > *:nth-child(5) { transition-delay: 400ms; }
.stagger-children > *:nth-child(6) { transition-delay: 500ms; }
.stagger-children > *:nth-child(7) { transition-delay: 600ms; }
.stagger-children > *:nth-child(8) { transition-delay: 700ms; }
.stagger-children > *:nth-child(9) { transition-delay: 800ms; }

/* --- Nav Active Indicator --- */
.nav-links a {
    position: relative;
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -6px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--accent-green);
    border-radius: 1px;
}

@media (max-width: 768px) {
    .nav-links a.active::after {
        display: none;
    }
    .nav-links a.active {
        border-left: 3px solid var(--accent-green);
        padding-left: 1rem;
    }
}

/* --- Hero Decoration (gradient orbs) --- */
.hero-decoration {
    position: relative;
    overflow: hidden;
}

.hero-decoration::before {
    content: '';
    position: absolute;
    top: -180px;
    left: -100px;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(34, 197, 94, 0.07) 0%, transparent 70%);
    border-radius: 50%;
    animation: heroFloat 12s ease-in-out infinite;
    pointer-events: none;
}

.hero-decoration::after {
    content: '';
    position: absolute;
    bottom: -200px;
    right: -80px;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(34, 197, 94, 0.04) 0%, transparent 70%);
    border-radius: 50%;
    animation: heroFloat 16s ease-in-out infinite reverse;
    pointer-events: none;
}

@keyframes heroFloat {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -25px) scale(1.05); }
    66% { transform: translate(-15px, 15px) scale(0.98); }
}

/* --- Card Icon Container --- */
.card-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: var(--glow-green);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card-icon svg {
    width: 24px;
    height: 24px;
    stroke: var(--accent-green);
    fill: none;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.article-card:hover .card-icon {
    transform: scale(1.1) rotate(-3deg);
    box-shadow: 0 0 20px rgba(34, 197, 94, 0.2);
}

/* Bitcoin variant */
.card-icon.bitcoin {
    background: rgba(247, 147, 26, 0.12);
}

.card-icon.bitcoin svg {
    stroke: #f7931a;
}

/* Orange variant */
.card-icon.orange {
    background: rgba(249, 115, 22, 0.12);
}

.card-icon.orange svg {
    stroke: #f97316;
}

/* Blue variant */
.card-icon.blue {
    background: rgba(59, 130, 246, 0.12);
}

.card-icon.blue svg {
    stroke: #3b82f6;
}

/* --- Improved Article Card Top Bar --- */
.article-card {
    position: relative;
    overflow: hidden;
}

.article-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-green-dim));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.5s cubic-bezier(0.22, 1, 0.36, 1);
}

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

/* --- Reading Progress Bar --- */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-green-dim));
    z-index: 999;
    width: 0%;
    transition: width 0.05s linear;
}

/* --- Back to Top Button --- */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 44px;
    height: 44px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all 0.3s ease;
    z-index: 50;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--accent-green);
    border-color: var(--accent-green);
    transform: translateY(-3px);
}

.back-to-top svg {
    width: 20px;
    height: 20px;
    stroke: var(--text-secondary);
    fill: none;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    transition: stroke 0.3s;
}

.back-to-top:hover svg {
    stroke: var(--bg-primary);
}

/* --- Section Divider --- */
.section-divider {
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-green), transparent);
    margin: 3rem auto;
    border: none;
    border-radius: 2px;
}

/* --- Value Item Icon (About page) --- */
.value-item .icon-svg {
    width: 40px;
    height: 40px;
    margin: 0 auto 0.75rem;
    border-radius: 10px;
    background: var(--glow-green);
    display: flex;
    align-items: center;
    justify-content: center;
}

.value-item .icon-svg svg {
    width: 22px;
    height: 22px;
    stroke: var(--accent-green);
    fill: none;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.value-item {
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.value-item:hover {
    transform: translateY(-4px);
    border-color: var(--accent-green);
}

/* --- CTA Box Enhancement --- */
.cta-box {
    position: relative;
    overflow: hidden;
}

.cta-box::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(34, 197, 94, 0.06) 0%, transparent 50%);
    pointer-events: none;
    animation: ctaGlow 8s ease-in-out infinite;
}

@keyframes ctaGlow {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(5%, -5%); }
}

/* --- Combined Result Enhancement --- */
.combined-result {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.combined-result:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 40px rgba(34, 197, 94, 0.15);
}

/* --- Tooltip for Guide TOC --- */
.toc a {
    transition: color 0.2s, padding-left 0.3s;
}

.toc a:hover {
    padding-left: 0.5rem;
}

/* --- Smooth Highlight Box entrance --- */
.highlight-box,
.warning-box,
.example-box {
    transition: border-color 0.3s ease;
}

.highlight-box:hover {
    border-color: var(--accent-green);
}

.warning-box:hover {
    border-color: #f97316;
}

/* --- Article Meta Enhancement --- */
.article-meta span {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

/* --- Footer Enhancement --- */
.footer-enhanced {
    position: relative;
}

.footer-enhanced::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent-green), transparent);
}

/* --- Prefers reduced motion --- */
@media (prefers-reduced-motion: reduce) {
    .animate-on-scroll,
    .animate-fade-left,
    .animate-fade-right,
    .animate-scale {
        opacity: 1;
        transform: none;
        transition: none;
    }

    .hero-decoration::before,
    .hero-decoration::after {
        animation: none;
    }

    .cta-box::before {
        animation: none;
    }

    @keyframes heroFloat {
        0%, 100% { transform: none; }
    }
}