/* 
   triangle-loader.css
   -------------------
   Beautiful three-triangle orbiting loader
   Based on three_triangle_loader.html design
   
   Features:
   - Three triangles in different sizes and shades of blue
   - Smooth orbiting animation
   - Elegant and modern
   - Minimal and professional
   
   Author: Karin Hershko and Afik Dadon
   Date: November 2025
*/

:root {
    --triangle-size-large: 120px;
    --triangle-size-medium: 80px;
    --triangle-size-small: 48px;
    
    --triangle-color-large: #bfe3ff;  /* lightest blue */
    --triangle-color-medium: #4da6ff; /* medium blue */
    --triangle-color-small: #005ebb;  /* darkest blue */
    
    --orbit-duration: 1.8s;
}

/* Loading Overlay - Dark Gradient Background (default for page loads) */
.triangle-loader-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, rgba(15, 23, 36, 0.96) 0%, rgba(7, 16, 36, 0.96) 100%);
    backdrop-filter: blur(4px);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    opacity: 1;
    transition: opacity 0.3s ease-out;
    will-change: opacity;
}

/* No background variant - for inline operations like answering questions */
.triangle-loader-overlay.no-background {
    background: transparent;
    backdrop-filter: none;
    pointer-events: none;
}

.triangle-loader-overlay.fade-out {
    opacity: 0;
    pointer-events: none;
}

/* Main Loader Container */
.triangle-loader-container {
    position: relative;
    width: calc(var(--triangle-size-large) * 1.6);
    height: calc(var(--triangle-size-large) * 1.6);
    display: flex;
    align-items: center;
    justify-content: center;
    transform: translateZ(0) rotate(0deg);
    filter: drop-shadow(0 6px 14px rgba(0, 0, 0, 0.6));
    animation: slow-rotate 8s linear infinite;
    will-change: transform;
}

/* Enhanced shadow for no-background mode */
.triangle-loader-overlay.no-background .triangle-loader-container {
    filter: drop-shadow(0 8px 20px rgba(0, 0, 0, 0.5));
    pointer-events: auto;
}

/* Base Triangle Style */
.triangle-loader {
    position: absolute;
    clip-path: polygon(50% 0%, 0% 100%, 100% 100%);
    transform-origin: 50% 50%;
    will-change: transform, opacity;
    border-radius: 6px;
    opacity: 0.98;
    mix-blend-mode: screen;
}

/* Large Triangle */
.triangle-loader.tri-large {
    width: var(--triangle-size-large);
    height: var(--triangle-size-large);
    background: var(--triangle-color-large);
    animation: orbit var(--orbit-duration) linear infinite;
    animation-delay: 0s;
    transform-origin: 50% calc(100% + 10px);
}

/* Medium Triangle */
.triangle-loader.tri-medium {
    width: var(--triangle-size-medium);
    height: var(--triangle-size-medium);
    background: var(--triangle-color-medium);
    animation: orbit var(--orbit-duration) linear infinite reverse;
    animation-delay: calc(var(--orbit-duration) / 6);
    transform-origin: 50% calc(100% + 6px);
}

/* Small Triangle */
.triangle-loader.tri-small {
    width: var(--triangle-size-small);
    height: var(--triangle-size-small);
    background: var(--triangle-color-small);
    animation: orbit var(--orbit-duration) linear infinite;
    animation-delay: calc(var(--orbit-duration) / 3);
    transform-origin: 50% calc(100% + 4px);
}

/* Orbit Animation - Triangles rotating around center */
@keyframes orbit {
    0% { 
        transform: rotate(0deg) translateY(-6px) scale(1); 
    }
    25% { 
        transform: rotate(90deg) translateY(-2px) scale(1.04); 
    }
    50% { 
        transform: rotate(180deg) translateY(0) scale(0.98); 
    }
    75% { 
        transform: rotate(270deg) translateY(-2px) scale(1.02); 
    }
    100% { 
        transform: rotate(360deg) translateY(-6px) scale(1); 
    }
}

/* Slow Rotation of Entire Loader */
@keyframes slow-rotate {
    0% { 
        transform: rotate(0deg); 
    }
    100% { 
        transform: rotate(360deg); 
    }
}

/* Loading Text */
.triangle-loader-text {
    position: absolute;
    bottom: -60px;
    width: 300px;
    text-align: center;
    color: #ffffff;
    font-size: 16px;
    font-weight: 500;
    letter-spacing: 1px;
    font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    opacity: 0.9;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.4);
}

/* Text styling for no-background mode */
.triangle-loader-overlay.no-background .triangle-loader-text {
    color: #4a90e2;
    font-weight: 600;
    text-shadow: 0 2px 4px rgba(255, 255, 255, 0.8), 
                 0 0 20px rgba(255, 255, 255, 0.6);
    pointer-events: auto;
}

/* Screen Reader Only */
.sr-only {
    position: absolute !important;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Responsive Design - Mobile */
@media (max-width: 768px) {
    :root {
        --triangle-size-large: 100px;
        --triangle-size-medium: 66px;
        --triangle-size-small: 40px;
    }
    
    .triangle-loader-text {
        font-size: 15px;
        width: 250px;
        bottom: -55px;
    }
}

@media (max-width: 420px) {
    :root {
        --triangle-size-large: 88px;
        --triangle-size-medium: 56px;
        --triangle-size-small: 36px;
    }
    
    .triangle-loader-text {
        font-size: 14px;
        width: 220px;
        bottom: -50px;
    }
}

/* Reduced Motion - Accessibility */
@media (prefers-reduced-motion: reduce) {
    .triangle-loader-container,
    .triangle-loader {
        animation: none;
    }
    
    .triangle-loader-container {
        animation: slow-rotate 16s linear infinite;
    }
}