:root {
    --bg-gradient: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-primary: #ffffff;
    --text-secondary: #b3b3b3;
    --accent-color: #00f2fe;
    --accent-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --danger-color: #ff4b2b;
    --card-hover-bg: rgba(255, 255, 255, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background: var(--bg-gradient);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    overflow-x: hidden;
}

.app-container {
    width: 100%;
    max-width: 1200px;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--glass-border);
}

header h1 {
    font-size: 2.5rem;
    font-weight: 600;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.primary-btn {
    background: var(--accent-gradient);
    color: #fff;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 242, 254, 0.3);
}

.secondary-btn {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--text-secondary);
    padding: 0.8rem 1.5rem;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.secondary-btn:hover {
    color: #fff;
    border-color: #fff;
    background: rgba(255, 255, 255, 0.1);
}

.notes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.note-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 1.5rem;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    display: flex;
    flex-direction: column;
    gap: 1rem;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    animation: fadeIn 0.5s ease forwards;
}

.note-card:hover {
    transform: translateY(-5px);
    background: var(--card-hover-bg);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.note-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
}

.note-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: #fff;
    word-break: break-word;
}

.note-date {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-top: 0.2rem;
}

.note-desc {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.5;
    word-break: break-word;
    flex-grow: 1;
}

.note-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
    margin-top: auto;
}

.icon-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.2rem;
    cursor: pointer;
    transition: color 0.3s ease;
    padding: 0.5rem;
}

.icon-btn.delete:hover {
    color: var(--danger-color);
}

/* Modal Styles */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(5px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.glass-effect {
    background: rgba(30, 40, 50, 0.8);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 2.5rem;
    width: 90%;
    max-width: 500px;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
    transform: scale(0.9);
    transition: transform 0.3s ease;
}

.modal-overlay.active .glass-effect {
    transform: scale(1);
}

#modal-title {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: #fff;
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group input,
.input-group textarea {
    width: 100%;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 1rem;
    color: #fff;
    font-size: 1rem;
    transition: border-color 0.3s ease, background 0.3s ease;
    outline: none;
}

.input-group input:focus,
.input-group textarea:focus {
    border-color: var(--accent-color);
    background: rgba(255, 255, 255, 0.1);
}

.input-group textarea {
    resize: vertical;
    min-height: 120px;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 1rem;
    margin-top: 2rem;
}

@media (max-width: 600px) {
    header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .primary-btn {
        width: 100%;
        justify-content: center;
    }
}