:root {
    --bg-gradient: linear-gradient(135deg, #009688 0%, #0d47a1 100%);
    --font-main: 'Segoe UI', system-ui, -apple-system, sans-serif;
    
    /* Tile Colors */
    --tile-yellow: #fcd757;
    --tile-green: #9ccc65;
    --tile-red-purple: linear-gradient(135deg, #ef5350, #ab47bc);
    --tile-yellow-alt: #ffca28;
    --tile-teal-yellow: linear-gradient(135deg, #26c6da, #ffee58);
    --tile-blue: linear-gradient(135deg, #42a5f5, #3f51b5);
    --tile-pink-purple: linear-gradient(135deg, #ba68c8, #f06292);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-main);
    background: var(--bg-gradient);
    min-height: 100vh;
    color: #fff;
}

/* Header */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 2rem 5%;
    flex-wrap: wrap;
    gap: 1rem;
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    letter-spacing: 2px;
}

.logo-icon {
    width: 40px;
    height: 45px;
    background-color: #fff;
    clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
    display: flex;
    justify-content: center;
    align-items: center;
}

.header-titles h2 {
    font-weight: 400;
    font-size: 1.8rem;
    line-height: 1.2;
}

.btn-admin {
    background: #ffca28;
    color: #333;
    padding: 10px 20px;
    text-decoration: none;
    font-weight: bold;
    border-radius: 20px;
    font-size: 0.9rem;
}

/* Grid Layout (Responsive) */
.grid-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    padding: 2rem 5%;
    max-width: 1200px;
    margin: 0 auto;
}

@media (min-width: 640px) {
    .grid-container { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1024px) {
    .grid-container { grid-template-columns: repeat(4, 1fr); }
}

/* Tiles */
.tile {
    border-radius: 16px;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: #1a1a1a;
    font-weight: 800;
    font-size: 1.2rem;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    min-height: 200px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.tile:hover {
    transform: scale(1.03);
    box-shadow: 0 10px 15px rgba(0,0,0,0.2);
}

.tile-icon { font-size: 3rem; margin-bottom: 1rem; }
.tile-yellow { background: var(--tile-yellow); grid-row: span 2; }
.tile-green { background: var(--tile-green); }
.tile-red-purple { background: var(--tile-red-purple); color: white; }
.tile-yellow-alt { background: var(--tile-yellow-alt); }
.tile-teal-yellow { background: var(--tile-teal-yellow); }
.tile-blue { background: var(--tile-blue); color: white; }
.tile-pink-purple { background: var(--tile-pink-purple); color: white; }

/* Modal SPA-like */
.modal-overlay {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.7);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 1;
    transition: opacity 0.3s ease;
}

.modal-overlay.hidden {
    opacity: 0;
    pointer-events: none;
}

.modal-content {
    background: white;
    color: #333;
    padding: 2.5rem;
    border-radius: 16px;
    width: 90%;
    max-width: 400px;
    position: relative;
    text-align: center;
    transform: translateY(0);
    transition: transform 0.3s ease;
}

.modal-overlay.hidden .modal-content { transform: translateY(-20px); }

.btn-close {
    position: absolute;
    top: 15px; right: 20px;
    font-size: 1.5rem;
    background: none;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: var(--bg-gradient);
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: bold;
    margin-top: 1.5rem;
    cursor: pointer;
    width: 100%;
}