/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px; /* Base font size for rem units */
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: var(--bg-primary);
    background-attachment: fixed;
    background-repeat: no-repeat;
    min-height: 100vh;
    position: relative;
}

/* Theme Variables */
:root {
    --bg-primary: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    --bg-card: #f7fafc;
    --text-primary: #2d3748;
    --text-secondary: #4A5568; /* Adjusted for better contrast in light mode */
    --border-color: #e2e8f0;
    --shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    --accent: #48bb78;
    --nav-link-hover: #ffffff; /* White for better contrast on green */
    --btn-secondary-bg: #a0aec0; /* For Cancel button */
    --btn-secondary-hover-bg: #718096; /* For Cancel button hover */
    --quote-text-color: #555; /* Adjusted for better visibility in light mode */
}

[data-theme="dark"] {
    --bg-primary: linear-gradient(135deg, #2d3748 0%, #1a202c 100%);
    --bg-card: #2d3748;
    --text-primary: #edf2f7;
    --text-secondary: #cbd5e0; /* Good contrast on dark background */
    --border-color: #4a5568;
    --shadow: 0 8px 24px rgba(0, 0, 0, 0.25);
    --accent: #68d391;
    --nav-link-hover: #68d391; /* Dark mode accent for hover */
    --btn-secondary-bg: #4a5568; /* Dark mode secondary button */
    --btn-secondary-hover-bg: #2d3748; /* Dark mode secondary button hover */
    --quote-text-color: #a0aec0; /* Lighter color for quote on dark primary background */
}

[data-theme="dark"] body {
    background: var(--bg-primary);
    color: var(--text-primary);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Preloader */
.preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    transition: opacity 0.5s ease;
}

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

.spinner {
    width: 3rem;
    height: 3rem;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid var(--accent);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.preloader p {
    color: var(--text-primary);
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    margin-top: 1rem;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Navigation Bar */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap; /* Allow wrapping on smaller screens */
    padding-bottom: 1rem; /* Add some padding at the bottom */
}

.nav-link {
    color: var(--text-primary); /* Uses theme variable */
    text-decoration: none;
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    font-weight: 500;
    transition: color 0.3s ease;
}
.nav-link:hover,
.nav-link:focus,
.nav-link.active {
    color: var(--nav-link-hover); /* Uses new hover color variable for better contrast */
    outline: none;
}

.nav-brand h1 {
    font-size: clamp(1.5rem, 4vw, 1.75rem);
    color: var(--text-primary);
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.hamburger {
    display: block;
    width: 1.5rem;
    height: 0.2rem;
    background: var(--text-primary);
    position: relative;
    transition: all 0.3s ease;
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    width: 1.5rem;
    height: 0.2rem;
    background: var(--text-primary);
    transition: all 0.3s ease;
}

.hamburger::before {
    top: -0.5rem;
}

.hamburger::after {
    top: 0.5rem;
}

.nav-toggle[aria-expanded="true"] .hamburger {
    background: transparent;
}

.nav-toggle[aria-expanded="true"] .hamburger::before {
    transform: rotate(45deg) translate(0.35rem, 0.35rem);
}

.nav-toggle[aria-expanded="true"] .hamburger::after {
    transform: rotate(-45deg) translate(0.35rem, -0.35rem);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 1.5rem;
    margin-top: 1rem;
}

/* Theme Toggle */
.theme-toggle {
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    padding: 0.5rem 0.75rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.25rem;
    font-size: 1.5rem;
}

.theme-toggle:hover, .theme-toggle:focus {
    background: rgba(255, 255, 255, 0.25);
    transform: scale(1.05);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

[data-theme="dark"] .theme-toggle .sun {
    opacity: 0.5;
}

[data-theme="light"] .theme-toggle .moon {
    opacity: 0.5;
}

/* Header Styles */
.header {
    text-align: center;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 12px;
    padding: 1.25rem;
    margin-bottom: 1.25rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
}
.header p {
    color: #fff; /* Uses theme variable */
    font-size: clamp(1rem, 3vw, 1.125rem);
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
}

.header h1 {
    font-size: clamp(1.75rem, 5vw, 2rem);
    color: var(--text-primary);
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
}

/* Quote Container */
.quote-container {
    margin-top: 1rem; /* Added margin-top to separate from budget info */
    font-style: italic;
    color: var(--quote-text-color); /* Uses new quote text color variable */
    font-size: clamp(0.9rem, 2.5vw, 1.1rem);
    padding: 0.75rem 1rem; /* Adjusted padding */
    border-radius: 8px;
    background: rgba(0, 0, 0, 0.05); /* Slightly darker background for quote */
    text-align: center; /* Center the quote text */
    display: none; /* Hidden by default, shown on larger screens */
}

/* Main Content */
.main {
    flex: 1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
}

/* Form Section */
.expense-form-section {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 1.25rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.expense-form-section h2 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: clamp(1.5rem, 4vw, 1.75rem);
    border-bottom: 2px solid var(--accent);
    padding-bottom: 0.5rem;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.375rem;
    font-weight: 600;
    color: var(--text-secondary);
    font-size: clamp(1rem, 2.5vw, 1.125rem);
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 0.625rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    transition: all 0.3s ease;
    background: var(--bg-card);
    color: var(--text-primary);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(72, 187, 120, 0.2);
}

/* Button Styles */
.btn {
    padding: 0.625rem;
    border: none;
    border-radius: 6px;
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    width: 100%;
}

.btn:focus {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.btn-primary {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(72, 187, 120, 0.3);
}

.btn-danger {
    background: linear-gradient(135deg, #f56565 0%, #e53e3e 100%);
    color: white;
}

.btn-danger:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(245, 101, 101, 0.3);
}

.btn-secondary { /* New style for secondary button (e.g., Cancel) */
    background: var(--btn-secondary-bg);
    color: white;
}

.btn-secondary:hover {
    background: var(--btn-secondary-hover-bg);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

/* Summary Section */
.summary-section {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 1.25rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.summary-card {
    text-align: center;
}

.summary-card h3 {
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    font-size: clamp(1.25rem, 3.5vw, 1.5rem);
}

.total-amount {
    font-size: clamp(2rem, 6vw, 2.5rem);
    font-weight: bold;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.expense-count {
    color: var(--text-secondary);
    font-size: clamp(1rem, 2.5vw, 1.125rem);
}

.budget-info {
    margin-top: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.625rem;
}

#budget-input {
    padding: 0.625rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    background: var(--bg-card);
    color: var(--text-primary);
}

#budget-input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(72, 187, 120, 0.2);
}

#budget-status {
    color: var(--text-secondary);
    font-size: clamp(1rem, 2.5vw, 1.125rem);
}

/* Filter Section */
.filter-section {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 1.25rem;
    box-shadow: var(--shadow);
    grid-column: span 2;
    border: 1px solid var(--border-color);
}

.filter-section h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: clamp(1.25rem, 3.5vw, 1.5rem);
}

.filter-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    align-items: center;
}

.filter-controls input,
.filter-controls select,
.filter-controls button {
    flex: 1;
    min-width: 120px;
    padding: 0.625rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    background: var(--bg-card);
    color: var(--text-primary);
}

.filter-controls input:focus,
.filter-controls select:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(72, 187, 120, 0.2);
}

/* Analytics Section */
.analytics-section {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 1.25rem;
    box-shadow: var(--shadow);
    grid-column: span 2;
    border: 1px solid var(--border-color);
}

.analytics-section h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: clamp(1.5rem, 4vw, 1.75rem);
    border-bottom: 2px solid var(--accent);
    padding-bottom: 0.5rem;
}

.analytics-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.tab-btn {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    background: transparent;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    color: var(--text-secondary);
    font-size: clamp(1rem, 2.5vw, 1.125rem);
}

.tab-btn:hover, .tab-btn:focus {
    border-color: var(--accent);
    transform: translateY(-1px);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

.tab-btn.active {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
}

.analytics-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 1rem;
    margin-bottom: 1.25rem;
}

.analytics-card {
    background: rgba(72, 187, 120, 0.1);
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border-color);
}

.analytics-card h4 {
    color: var(--text-secondary);
    font-size: clamp(0.875rem, 2.5vw, 1rem);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
}

.category-info {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.category-name {
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.category-amount {
    font-size: clamp(1.25rem, 3.5vw, 1.5rem);
    font-weight: bold;
    color: var(--accent);
}

.daily-avg, .period-total {
    font-size: clamp(1.25rem, 3.5vw, 1.5rem);
    font-weight: bold;
    color: var(--accent);
}

.chart-container {
    background: rgba(72, 187, 120, 0.05);
    border-radius: 8px;
    padding: 1rem;
    text-align: center;
    max-width: 400px;
    margin: 0 auto;
    height: 300px; /* Set a default height for the container */
    position: relative; /* Added for message positioning */
}

.chart-container canvas {
    width: 100% !important;
    height: 100% !important; /* Make canvas take full height of its container */
}

.chart-container .no-data-message { /* Added for no data state */
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: var(--text-secondary);
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    text-align: center;
    padding: 1rem;
    background: var(--bg-card);
    border-radius: 8px;
    box-shadow: var(--shadow);
    display: none; /* Hidden by default */
}


/* Expenses List */
.expenses-list-section {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 1.25rem;
    box-shadow: var(--shadow);
    grid-column: span 2;
    border: 1px solid var(--border-color);
}

.expenses-list-section h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: clamp(1.5rem, 4vw, 1.75rem);
    border-bottom: 2px solid var(--accent);
    padding-bottom: 0.5rem;
}

.expenses-list {
    max-height: 400px;
    overflow-y: auto;
    padding-right: 0.5rem;
}

.expense-item {
    background: rgba(72, 187, 120, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem;
    margin-bottom: 0.75rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: all 0.3s ease;
}

.expense-item:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-color: var(--accent);
}

.expense-details {
    flex: 1;
}

.expense-description {
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.expense-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: clamp(0.875rem, 2.5vw, 1rem);
}

.expense-category {
    background: var(--accent);
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 16px;
    font-size: clamp(0.875rem, 2vw, 1rem);
}

.expense-amount {
    font-size: clamp(1.125rem, 3vw, 1.25rem);
    font-weight: bold;
    color: #e53e3e;
}

.expense-actions {
    margin-left: 0.75rem;
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.edit-btn, .delete-btn {
    padding: 0.5rem 0.75rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: clamp(0.875rem, 2.5vw, 1rem);
    transition: all 0.3s ease;
}

.edit-btn {
    background: #2b6cb0;
    color: white;
}

.edit-btn:hover, .edit-btn:focus {
    background: #2c5282;
    transform: scale(1.05);
    outline: 2px solid var(--accent);
}

.delete-btn {
    background: #f56565;
    color: white;
}

.delete-btn:hover, .delete-btn:focus {
    background: #e53e3e;
    transform: scale(1.05);
    outline: 2px solid var(--accent);
}

/* No Expenses State */
.no-expenses {
    text-align: center;
    padding: 1.5rem;
    color: var(--text-secondary);
}

.no-expenses p {
    margin-bottom: 0.5rem;
    font-size: clamp(1rem, 2.5vw, 1.125rem);
}

/* Message Styles (for success/error pop-ups) */
.message {
    position: fixed;
    top: 1rem;
    right: 1rem;
    padding: 0.75rem 1.25rem;
    border-radius: 6px;
    color: white;
    font-weight: 600;
    font-size: clamp(1rem, 2.5vw, 1.125rem);
    z-index: 1000;
    transform: translateX(100%);
    opacity: 0; /* Changed to opacity for smoother hide */
    visibility: hidden; /* Ensure it's not clickable when hidden */
    transition: transform 0.3s ease-out, opacity 0.3s ease-out, visibility 0.3s ease-out;
}

.message.show {
    transform: translateX(0);
    opacity: 1;
    visibility: visible;
}

.message.success {
    background: #38a169;
}

.message.error {
    background: #e53e3e;
}

.hidden {
    display: none;
}

/* Footer */
.footer {
    text-align: center;
    padding: 1rem;
    color: #f7fafc;
    margin-top: auto;
    font-size: clamp(0.875rem, 2.5vw, 1rem);
}

.social-links {
    margin-top: 0.5rem;
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.social-icon {
    width: 1.5rem;
    height: 1.5rem;
    transition: transform 0.3s ease;
    vertical-align: middle; /* Align SVG icons properly */
    fill: white; /* Explicitly set fill color to white */
}

.social-icon:hover {
    transform: scale(1.1);
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: var(--bg-card);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: var(--accent);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
    background: #38a169;
}

/* Custom Confirmation Modal Styles */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6); /* Semi-transparent black overlay */
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000; /* Above everything else */
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

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

.modal-content {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    text-align: center;
    max-width: 400px;
    width: 90%;
    transform: translateY(-20px); /* Initial state for animation */
    transition: transform 0.3s ease-out;
}

.modal-overlay.visible .modal-content {
    transform: translateY(0); /* Final state for animation */
}

.modal-content p {
    font-size: clamp(1.125rem, 3vw, 1.25rem);
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.modal-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.modal-actions .btn {
    width: auto; /* Allow buttons to size naturally */
    flex: 1; /* Distribute space evenly */
    padding: 0.75rem 1.5rem;
}


/* Responsive Design */
@media (min-width: 769px) { /* Show quote only on desktop and larger */
    .quote-container {
        display: block;
    }
}

@media (max-width: 768px) {
    .main {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .filter-section, .analytics-section, .expenses-list-section {
        grid-column: span 1;
    }

    .filter-controls {
        flex-direction: column;
        align-items: stretch;
    }

    .header-top {
        flex-direction: column;
        align-items: center;
        gap: 0.625rem;
    }

    .expense-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }

    .expense-actions {
        margin-left: 0;
        align-self: flex-end;
        width: 100%;
        justify-content: flex-end;
    }

    .analytics-cards {
        grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); /* Adjusted minmax for smaller screens */
        gap: 0.75rem; /* Slightly smaller gap */
    }

    .chart-container {
        max-width: 100%;
    }

    .chart-container canvas {
        height: 250px !important; /* Retained !important for mobile to ensure height */
    }

    /* Navigation Bar for Tablet/Mobile */
    .nav-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        flex-direction: column;
        gap: 0.5rem;
        margin-top: 0;
        background: rgba(255, 255, 255, 0.1);
        padding: 1rem;
        border-radius: 8px;
    }

    .nav-menu.active {
        display: flex;
    }

    .navbar {
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0.75rem;
    }

    .header {
        padding: 1rem;
    }

    .expense-form-section,
    .summary-section,
    .filter-section,
    .analytics-section,
    .expenses-list-section {
        padding: 1rem;
    }

    .btn {
        padding: 0.5rem;
        font-size: clamp(0.875rem, 2.5vw, 1rem);
    }

    .tab-btn {
        padding: 0.375rem 0.75rem;
        font-size: clamp(0.875rem, 2vw, 1rem);
    }

    .analytics-tabs {
        justify-content: center;
    }

    .analytics-cards {
        grid-template-columns: 1fr; /* Stack cards on very small screens */
    }

    .chart-container canvas {
        height: 200px !important; /* Retained !important for mobile to ensure height */
    }
}