/* HomeworkGrader Payment Website - Modern Clean Style */

/* CSS Variables */
:root {
    --primary-color: #1a73e8;
    --primary-dark: #1557b0;
    --secondary-color: #5f6368;
    --success-color: #34a853;
    --warning-color: #ea8600;
    --error-color: #d93025;
    --background-color: #f8f9fa;
    --surface-color: #ffffff;
    --border-color: #dadce0;
    --text-primary: #202124;
    --text-secondary: #5f6368;
    --text-light: #80868b;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.1);
    --shadow-md: 0 2px 8px rgba(0,0,0,0.1);
    --shadow-lg: 0 4px 16px rgba(0,0,0,0.12);
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --transition: all 0.2s ease;
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

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

img {
    max-width: 100%;
    height: auto;
}

/* Layout */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.main-content {
    flex: 1;
    padding: 40px 0;
}

/* Header */
.header {
    background-color: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.logo:hover {
    color: var(--text-primary);
}

.nav {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-link {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    font-weight: 500;
    padding: 8px 0;
    border-bottom: 2px solid transparent;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

/* Mobile Menu */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    padding: 8px;
    cursor: pointer;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--text-primary);
    margin: 5px 0;
    transition: var(--transition);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 24px;
    font-size: 0.9375rem;
    font-weight: 500;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
    white-space: nowrap;
}

.btn-primary {
    background-color: var(--primary-color);
    color: #ffffff;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    color: #ffffff;
}

.btn-secondary {
    background-color: var(--surface-color);
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

.btn-secondary:hover {
    background-color: #e8f0fe;
}

.btn-outline {
    background-color: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.btn-outline:hover {
    background-color: var(--background-color);
    color: var(--text-primary);
}

.btn-success {
    background-color: var(--success-color);
    color: #ffffff;
}

.btn-warning {
    background-color: var(--warning-color);
    color: #ffffff;
}

.btn-large {
    padding: 14px 32px;
    font-size: 1rem;
}

.btn-small {
    padding: 6px 16px;
    font-size: 0.875rem;
}

.btn-block {
    display: flex;
    width: 100%;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* Cards */
.card {
    background-color: var(--surface-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: var(--transition);
}

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

.card-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
}

.card-body {
    padding: 24px;
}

.card-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--border-color);
    background-color: var(--background-color);
}

/* Forms */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-primary);
}

.form-control {
    width: 100%;
    padding: 12px 16px;
    font-size: 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background-color: var(--surface-color);
    color: var(--text-primary);
    transition: var(--transition);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.1);
}

.form-control::placeholder {
    color: var(--text-light);
}

.form-control:disabled,
.form-control[readonly] {
    background-color: var(--background-color);
    cursor: not-allowed;
}

.form-hint {
    margin-top: 6px;
    font-size: 0.875rem;
    color: var(--text-light);
}

.form-error {
    margin-top: 6px;
    font-size: 0.875rem;
    color: var(--error-color);
}

select.form-control {
    appearance: none;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='%235f6368'%3e%3cpath d='M7 10l5 5 5-5z'/%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 20px;
    padding-right: 40px;
}

/* Radio & Checkbox Cards */
.option-card {
    position: relative;
    display: block;
    padding: 20px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.option-card:hover {
    border-color: var(--primary-color);
    background-color: #f8fbff;
}

.option-card input {
    position: absolute;
    opacity: 0;
}

.option-card input:checked + .option-content {
    color: var(--primary-color);
}

.option-card:has(input:checked) {
    border-color: var(--primary-color);
    background-color: #e8f0fe;
}

.option-card .badge {
    position: absolute;
    top: -10px;
    right: 16px;
}

/* Pricing Cards */
.pricing-card {
    position: relative;
    padding: 32px 24px;
    text-align: center;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

.pricing-card:hover {
    border-color: var(--primary-color);
}

.pricing-card.recommended {
    border-color: var(--primary-color);
}

.pricing-card .plan-name {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.pricing-card .plan-price {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.pricing-card .plan-price .currency {
    font-size: 1.25rem;
    font-weight: 500;
}

.pricing-card .original-price {
    font-size: 1rem;
    color: var(--text-light);
    text-decoration: line-through;
    margin-bottom: 16px;
}

.pricing-card .plan-desc {
    color: var(--text-secondary);
    margin-bottom: 24px;
}

/* Badges */
.badge {
    display: inline-block;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 100px;
    text-transform: uppercase;
}

.badge-primary {
    background-color: var(--primary-color);
    color: #ffffff;
}

.badge-success {
    background-color: var(--success-color);
    color: #ffffff;
}

.badge-warning {
    background-color: var(--warning-color);
    color: #ffffff;
}

.badge-error {
    background-color: var(--error-color);
    color: #ffffff;
}

.badge-outline {
    background-color: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

/* Alerts */
.alert {
    padding: 16px 20px;
    border-radius: var(--radius-md);
    margin-bottom: 20px;
    border: 1px solid;
}

.alert-success {
    background-color: #e6f4ea;
    border-color: #34a853;
    color: #137333;
}

.alert-warning {
    background-color: #fef7e0;
    border-color: #ea8600;
    color: #b06000;
}

.alert-error {
    background-color: #fce8e6;
    border-color: #d93025;
    color: #c5221f;
}

.alert-info {
    background-color: #e8f0fe;
    border-color: #1a73e8;
    color: #1967d2;
}

/* Tables */
.table-container {
    overflow-x: auto;
}

.table {
    width: 100%;
    border-collapse: collapse;
}

.table th,
.table td {
    padding: 14px 16px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.table th {
    font-weight: 600;
    color: var(--text-secondary);
    background-color: var(--background-color);
}

.table tr:hover td {
    background-color: var(--background-color);
}

/* Product Grid */
.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
}

.product-card {
    display: flex;
    flex-direction: column;
}

.product-card .card-body {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.product-card .product-name {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.product-card .product-desc {
    color: var(--text-secondary);
    margin-bottom: 16px;
    flex: 1;
}

.product-card .product-price {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-color);
}

.product-card .price-suffix {
    font-size: 0.875rem;
    color: var(--text-light);
    font-weight: normal;
}

/* Pricing Grid */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
    margin: 40px 0;
}

/* Feature List */
.feature-list {
    list-style: none;
    padding: 0;
}

.feature-list li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 8px 0;
}

.feature-list li::before {
    content: "";
    width: 20px;
    height: 20px;
    background-color: var(--success-color);
    border-radius: 50%;
    flex-shrink: 0;
    margin-top: 2px;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='white'%3e%3cpath d='M9 16.17L4.83 12l-1.42 1.41L9 19 21 7l-1.41-1.41z'/%3e%3c/svg%3e");
    background-size: 14px;
    background-position: center;
    background-repeat: no-repeat;
}

/* Page Header */
.page-header {
    margin-bottom: 40px;
}

.page-title {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.page-subtitle {
    color: var(--text-secondary);
    font-size: 1.125rem;
}

/* Hero Section */
.hero {
    padding: 80px 0;
    text-align: center;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 32px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

/* Section */
.section {
    padding: 60px 0;
}

.section-title {
    font-size: 1.75rem;
    font-weight: 600;
    margin-bottom: 16px;
    text-align: center;
}

.section-subtitle {
    color: var(--text-secondary);
    text-align: center;
    max-width: 600px;
    margin: 0 auto 40px;
}

/* Activation Code Display */
.activation-code {
    background-color: var(--background-color);
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    text-align: center;
    margin: 24px 0;
}

.activation-code code {
    display: block;
    font-family: "SF Mono", Monaco, "Courier New", monospace;
    font-size: 1rem;
    word-break: break-all;
    color: var(--text-primary);
    margin-bottom: 16px;
    line-height: 1.8;
}

/* Footer */
.footer {
    background-color: var(--surface-color);
    border-top: 1px solid var(--border-color);
    padding: 40px 0;
    margin-top: auto;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-text {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.footer-links {
    display: flex;
    gap: 24px;
}

.footer-links a {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.footer-links a:hover {
    color: var(--primary-color);
}

/* Order Status */
.order-status {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.status-pending .status-dot {
    background-color: var(--warning-color);
}

.status-paid .status-dot {
    background-color: var(--success-color);
}

.status-failed .status-dot {
    background-color: var(--error-color);
}

/* Payment Method Selection */
.payment-methods {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin: 24px 0;
}

.payment-method {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.payment-method:hover {
    border-color: var(--primary-color);
}

.payment-method input {
    display: none;
}

.payment-method:has(input:checked) {
    border-color: var(--primary-color);
    background-color: #e8f0fe;
}

.payment-method .method-icon {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--background-color);
    border-radius: var(--radius-sm);
}

.payment-method .method-name {
    font-weight: 500;
}

/* Loading */
.loading {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
}

.spinner {
    width: 32px;
    height: 32px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Utilities */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-muted { color: var(--text-secondary); }
.text-small { font-size: 0.875rem; }
.text-large { font-size: 1.125rem; }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mt-4 { margin-top: 32px; }
.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.mb-4 { margin-bottom: 32px; }

.d-flex { display: flex; }
.align-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 8px; }
.gap-2 { gap: 16px; }
.gap-3 { gap: 24px; }

/* Responsive */
@media (max-width: 768px) {
    .nav {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background-color: var(--surface-color);
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--border-color);
        gap: 0;
    }

    .nav.active {
        display: flex;
    }

    .nav-link {
        padding: 12px 0;
        border-bottom: none;
    }

    .menu-toggle {
        display: block;
    }

    .hero {
        padding: 40px 0;
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .page-title {
        font-size: 1.5rem;
    }

    .section {
        padding: 40px 0;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .pricing-card .plan-price {
        font-size: 2rem;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .table th,
    .table td {
        padding: 10px 12px;
        font-size: 0.875rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .card-body {
        padding: 16px;
    }

    .btn {
        padding: 10px 16px;
    }

    .pricing-grid {
        grid-template-columns: 1fr;
    }

    .product-grid {
        grid-template-columns: 1fr;
    }
}