/* ============================================
   Debt Optimizer - Enhanced Styles
   ============================================ */

/* --- CSS Variables & Theming --- */
:root {
    --primary: #4361ee;
    --primary-dark: #3a56d4;
    --primary-light: #eef0ff;
    --secondary: #7209b7;
    --success: #06d6a0;
    --success-dark: #05b88a;
    --danger: #ef476f;
    --warning: #ffd166;
    --info: #118ab2;
    --bg: #f4f6fb;
    --bg-card: #ffffff;
    --text: #2b2d42;
    --text-muted: #8d99ae;
    --border: #e2e8f0;
    --shadow: 0 4px 24px rgba(43, 45, 66, 0.08);
    --shadow-lg: 0 8px 40px rgba(43, 45, 66, 0.12);
    --shadow-hover: 0 8px 32px rgba(67, 97, 238, 0.15);
    --radius: 16px;
    --radius-sm: 10px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --navbar-gradient: linear-gradient(135deg, #4361ee 0%, #7209b7 100%);
    --btn-gradient: linear-gradient(135deg, #4361ee 0%, #3a56d4 100%);
}

[data-theme="dark"] {
    --bg: #1a1a2e;
    --bg-card: #16213e;
    --text: #edf2f4;
    --text-muted: #8d99ae;
    --border: #2d3561;
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.4);
    --shadow-hover: 0 8px 32px rgba(67, 97, 238, 0.25);
    --primary-light: #1e2a4a;
}

/* --- Base --- */
* {
    box-sizing: border-box;
}

body {
    background-color: var(--bg);
    color: var(--text);
    font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
    transition: background-color 0.3s ease, color 0.3s ease;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

body > .container.py-3 {
    flex: 1;
}

a {
    color: var(--primary);
    transition: var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

/* --- Navbar --- */
.navbar {
    background: var(--navbar-gradient) !important;
    padding: 0.75rem 0;
    border: none;
    box-shadow: 0 2px 20px rgba(67, 97, 238, 0.3);
}

.navbar-brand {
    font-size: 1.3rem;
    letter-spacing: -0.5px;
}

.navbar .nav-link {
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    font-size: 0.9rem;
}

.navbar .nav-link:hover,
.navbar .nav-link.active {
    background: rgba(255, 255, 255, 0.15);
}

/* --- Cards --- */
.card {
    border: 1px solid var(--border);
    background: var(--bg-card);
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-radius: var(--radius) !important;
}

.card:hover {
    box-shadow: var(--shadow-hover);
}

/* --- Buttons --- */
.btn-primary {
    background: var(--btn-gradient);
    border: none;
    font-weight: 600;
    letter-spacing: 0.3px;
    padding: 0.6rem 1.5rem;
    transition: var(--transition);
}

.btn-primary:hover {
    background: linear-gradient(135deg, #3a56d4 0%, #2d46b9 100%);
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(67, 97, 238, 0.35);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-outline-primary {
    color: var(--primary);
    border-color: var(--primary);
    font-weight: 500;
}

.btn-outline-primary:hover {
    background: var(--primary);
    border-color: var(--primary);
    transform: translateY(-1px);
}

.btn-outline-secondary {
    border-style: dashed;
    border-width: 2px;
    font-weight: 500;
    color: var(--text-muted);
    transition: var(--transition);
}

.btn-outline-secondary:hover {
    border-style: solid;
    background: var(--primary-light);
    border-color: var(--primary);
    color: var(--primary);
}

/* --- Form Controls --- */
.form-control,
.input-group-text {
    border-color: var(--border);
    transition: var(--transition);
}

[data-theme="dark"] .form-control,
[data-theme="dark"] .input-group-text {
    background-color: #1a1a2e;
    border-color: var(--border);
    color: var(--text);
}

.form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.15);
}

[data-theme="dark"] .form-control:focus {
    background-color: #1a1a2e;
    color: var(--text);
}

.form-label {
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text);
    margin-bottom: 0.4rem;
}

.form-text {
    color: var(--text-muted);
    font-size: 0.8rem;
}

/* --- Tables --- */
.table {
    --bs-table-bg: transparent;
    --bs-table-color: var(--text);
}

.table th {
    font-weight: 700;
    text-transform: uppercase;
    font-size: 0.7rem;
    letter-spacing: 1.2px;
    color: var(--text-muted);
    border-bottom-width: 2px;
    padding: 0.75rem;
}

.table td {
    padding: 0.75rem;
    vertical-align: middle;
    font-size: 0.9rem;
    border-color: var(--border);
}

.table-hover tbody tr:hover {
    background-color: var(--primary-light);
}

[data-theme="dark"] .table-light {
    --bs-table-bg: var(--bg-card);
    --bs-table-color: var(--text);
}

/* --- Stat Cards (Results page) --- */
.stat-card {
    border: none;
    border-radius: var(--radius) !important;
    overflow: hidden;
    position: relative;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.1) 0%, transparent 100%);
    pointer-events: none;
}

.stat-card .stat-value {
    font-size: 2.2rem;
    font-weight: 800;
    letter-spacing: -1px;
    line-height: 1.2;
}

.stat-card .stat-label {
    font-size: 0.85rem;
    font-weight: 500;
    opacity: 0.85;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.stat-card .stat-icon {
    font-size: 3rem;
    opacity: 0.15;
    position: absolute;
    top: 15px;
    right: 20px;
}

/* --- Excel Table Styles --- */
.excel-table {
    border-collapse: collapse;
    width: 100%;
    margin-bottom: 0;
}

.excel-table th {
    background-color: var(--bg);
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 700;
    padding: 0.75rem;
    border: 1px solid var(--border);
    vertical-align: middle;
    text-align: center;
    letter-spacing: 1px;
}

[data-theme="dark"] .excel-table th {
    background-color: var(--bg-card);
    border-color: var(--border);
}

.excel-table td {
    padding: 0;
    border: 1px solid var(--border);
    position: relative;
    vertical-align: middle;
}

.excel-input,
.excel-input-group .form-control {
    border: none !important;
    border-radius: 0 !important;
    background-color: transparent !important;
    box-shadow: none !important;
    padding: 0.6rem 0.6rem !important;
    height: 100%;
    width: 100%;
}

.excel-input:focus,
.excel-input-group:focus-within {
    outline: 2px solid var(--primary) !important;
    outline-offset: -2px;
    background-color: var(--bg-card) !important;
    z-index: 2;
    position: relative;
}

[data-theme="dark"] .excel-input:focus,
[data-theme="dark"] .excel-input-group:focus-within {
    background-color: var(--bg-card) !important;
}

.excel-input-group {
    height: 100%;
    display: flex;
    align-items: center;
}

.excel-input-group .input-group-text {
    border: none !important;
    background-color: transparent !important;
    padding: 0 0.2rem 0 0.5rem;
    color: var(--text-muted);
}

/* --- Debt Rows --- */
.debt-row {
    animation: slideIn 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    background: var(--bg-card);
    transition: var(--transition);
}

.debt-row:hover {
    background-color: var(--primary-light) !important;
}

[data-theme="dark"] .debt-row:hover {
    background-color: rgba(67, 97, 238, 0.15) !important;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* --- Alerts --- */
.alert {
    border: none;
    border-radius: var(--radius-sm);
    font-weight: 500;
}

/* --- Dark Mode Toggle --- */
.theme-toggle {
    background: rgba(255, 255, 255, 0.15);
    border: none;
    color: white;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    font-size: 1rem;
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: rotate(20deg);
}

/* --- Footer --- */
.site-footer {
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    padding: 1.5rem 0;
    margin-top: auto;
    color: var(--text-muted);
    font-size: 0.85rem;
}

[data-theme="dark"] .site-footer {
    background: #16213e;
}

/* --- Page Header --- */
.page-header {
    margin-bottom: 2rem;
}

.page-header h2 {
    font-weight: 800;
    letter-spacing: -0.5px;
    color: var(--text);
}

.page-header p {
    color: var(--text-muted);
    font-size: 1.05rem;
    max-width: 600px;
    margin: 0 auto;
}

/* --- Method Badge --- */
.method-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    background: var(--primary-light);
    color: var(--primary);
    padding: 0.4rem 0.9rem;
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.5px;
}

/* --- Progress Bar --- */
.payoff-progress {
    height: 8px;
    border-radius: 4px;
    background: var(--border);
    overflow: hidden;
}

.payoff-progress .progress-fill {
    height: 100%;
    border-radius: 4px;
    background: var(--btn-gradient);
    transition: width 1s cubic-bezier(0.4, 0, 0.2, 1);
}

/* --- Auth Pages --- */
.auth-icon {
    width: 70px;
    height: 70px;
    border-radius: 50%;
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 1.8rem;
    color: var(--primary);
}

/* --- Profile Avatar --- */
.profile-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: var(--btn-gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
    font-size: 2rem;
    color: white;
    box-shadow: 0 4px 16px rgba(67, 97, 238, 0.3);
}

/* --- Tooltip Styles --- */
.info-tooltip {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--text-muted);
    color: white;
    font-size: 0.65rem;
    font-weight: 700;
    cursor: help;
    margin-left: 0.35rem;
    vertical-align: middle;
}

/* --- Summary Insight Cards --- */
.insight-card {
    background: var(--primary-light);
    border-radius: var(--radius-sm);
    padding: 1rem 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.insight-card .insight-icon {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    flex-shrink: 0;
}

/* --- Live Preview Badge --- */
.live-badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    background: #d1fae5;
    color: #065f46;
    padding: 2px 8px;
    border-radius: 50px;
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 0.3px;
}

[data-theme="dark"] .live-badge {
    background: #064e3b;
    color: #6ee7b7;
}

.live-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: #10b981;
    animation: pulse-dot 1.5s infinite;
    display: inline-block;
    flex-shrink: 0;
}

@keyframes pulse-dot {
    0%, 100% { opacity: 1; transform: scale(1); }
    50%       { opacity: 0.5; transform: scale(0.7); }
}

/* Tighter cells for spreadsheet table */
.excel-table td {
    padding: 0 !important;
}

.excel-table .excel-input {
    padding: 0.45rem 0.5rem !important;
    font-size: 0.83rem !important;
}

/* --- Responsive Tweaks --- */
@media (max-width: 768px) {
    .stat-card .stat-value {
        font-size: 1.6rem;
    }

    .stat-card .stat-icon {
        font-size: 2rem;
    }

    .card-body.p-5 {
        padding: 1.5rem !important;
    }

    .debt-row .row {
        gap: 0.25rem;
    }

    .navbar-brand {
        font-size: 1.1rem;
    }
}

/* --- Loading Spinner --- */
.spinner-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.85);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    backdrop-filter: blur(4px);
}

[data-theme="dark"] .spinner-overlay {
    background: rgba(26, 26, 46, 0.85);
}

.spinner-overlay.active {
    display: flex;
}

.spinner-dots {
    display: flex;
    gap: 6px;
}

.spinner-dots span {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--primary);
    animation: bounce 1.4s infinite ease-in-out both;
}

.spinner-dots span:nth-child(1) { animation-delay: -0.32s; }
.spinner-dots span:nth-child(2) { animation-delay: -0.16s; }

@keyframes bounce {
    0%, 80%, 100% { transform: scale(0); }
    40% { transform: scale(1); }
}

/* --- Scrollbar (Webkit) --- */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg);
}

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary);
}

/* --- Dark mode Bootstrap overrides --- */
[data-theme="dark"] .bg-light {
    background-color: var(--bg) !important;
}

[data-theme="dark"] .text-primary {
    color: #6c8aff !important;
}

[data-theme="dark"] .text-muted {
    color: var(--text-muted) !important;
}

[data-theme="dark"] .card {
    background: var(--bg-card);
    border-color: var(--border);
}

[data-theme="dark"] .alert-danger {
    background: #3d1c28;
    color: #f8a4b8;
}

[data-theme="dark"] .alert-success {
    background: #1c3d2e;
    color: #a4f8d0;
}

[data-theme="dark"] .alert-info {
    background: #1c2e3d;
    color: #a4d8f8;
}

[data-theme="dark"] .btn-close {
    filter: invert(1);
}

/* --- Upload Dropzone --- */
.upload-dropzone {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    background: var(--bg);
}

.upload-dropzone:hover,
.upload-dropzone.dragover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.upload-dropzone .upload-icon {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto;
    font-size: 1.6rem;
    color: var(--primary);
    transition: var(--transition);
}

.upload-dropzone:hover .upload-icon,
.upload-dropzone.dragover .upload-icon {
    background: var(--primary);
    color: white;
    transform: translateY(-2px);
}

.upload-file-input {
    position: absolute;
    inset: 0;
    opacity: 0;
    cursor: pointer;
}

[data-theme="dark"] .upload-dropzone {
    background: var(--bg-card);
}