/* =====================================================
   Well Testing Community Platform - Main Styles
   Professional engineering-style design
   ===================================================== */

/* CSS Variables */
:root {
    --primary-color: #3b82f6;
    --primary-dark: #2563eb;
    --secondary-color: #1e293b;
    --dark-bg: #0f172a;
    --darker-bg: #020617;
    --card-bg: #1e293b;
    --border-color: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --hover-bg: #334155;
    --white: #ffffff;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--dark-bg);
    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: color 0.3s ease;
}

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

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

/* Navigation */
.navbar {
    background-color: var(--secondary-color);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
}

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

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
    font-size: 1.5rem;
    color: var(--white);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.nav-link {
    color: var(--text-secondary);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    transition: all 0.3s ease;
    border: none;
    background: transparent;
    cursor: pointer;
    font-size: 0.95rem;
}

.nav-link:hover {
    color: var(--text-primary);
    background-color: var(--hover-bg);
}

.nav-link.active {
    color: var(--primary-color);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* Mobile Menu Overlay */
.mobile-menu-overlay {
    position: fixed;
    top: 0;
    right: -100%;
    width: 100%;
    height: 100vh;
    background-color: var(--secondary-color);
    z-index: 2000;
    transition: right 0.3s ease;
    overflow-y: auto;
}

.mobile-menu-overlay.active {
    right: 0;
}

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

.close-btn {
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 2.5rem;
    cursor: pointer;
    line-height: 1;
    padding: 0;
    width: 40px;
    height: 40px;
}

.mobile-menu-search {
    padding: 1rem;
}

.mobile-menu-search input {
    width: 100%;
    padding: 12px 16px;
    background-color: var(--dark-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
}

.mobile-menu-content {
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.mobile-menu-item {
    padding: 1rem;
    color: var(--text-primary);
    background-color: transparent;
    border: none;
    border-radius: 8px;
    text-align: left;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.mobile-menu-item:hover {
    background-color: var(--hover-bg);
}

.mobile-menu-item.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.mobile-menu-item.text-danger {
    color: var(--danger-color);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--secondary-color), var(--darker-bg));
    padding: 4rem 0;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 700px;
    margin: 0 auto 2rem;
    line-height: 1.7;
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2rem 0;
}

/* Search and Filter Bar */
.search-bar {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.search-input {
    flex: 1;
    min-width: 250px;
    padding: 12px 16px;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.filter-select {
    padding: 12px 16px;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
    cursor: pointer;
}

/* Section Title */
.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

/* Questions List */
.questions-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.question-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 1.5rem;
    transition: all 0.3s ease;
}

.question-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.1);
}

.question-card-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.question-card-title a {
    color: var(--text-primary);
}

.question-card-title a:hover {
    color: var(--primary-color);
}

.question-card-description {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.question-card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.question-meta {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.meta-item {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.meta-item strong {
    color: var(--text-secondary);
}

.answers-badge {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

/* Question Detail Page */
.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.back-link:hover {
    color: var(--primary-color);
}

.question-detail {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 2rem;
    margin-bottom: 2rem;
}

.question-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 1rem;
}

.question-detail-title {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    flex: 1;
}

.question-detail-body {
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: 1.05rem;
    margin-top: 1.5rem;
    white-space: pre-wrap;
}

/* Answers Section */
.answers-section {
    margin-bottom: 2rem;
}

.answers-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.answer-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 1.5rem;
    position: relative;
}

.answer-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.answer-actions {
    display: flex;
    gap: 0.5rem;
}

.answer-content {
    color: var(--text-secondary);
    line-height: 1.7;
    white-space: pre-wrap;
}

.like-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 6px 12px;
    background-color: transparent;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.875rem;
}

.like-btn:hover {
    background-color: var(--hover-bg);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.like-btn.liked {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    color: var(--white);
}

/* Answer Form */
.answer-form-section {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 2rem;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.form-input,
.form-textarea {
    width: 100%;
    padding: 12px 16px;
    background-color: var(--dark-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-textarea {
    resize: vertical;
    min-height: 100px;
}

.form-hint {
    display: block;
    margin-top: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-muted);
}

.form-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
    margin-top: 1.5rem;
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

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

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

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

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

.btn-danger {
    background-color: var(--danger-color);
    color: var(--white);
}

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-block {
    width: 100%;
}

.btn-lg {
    padding: 14px 28px;
    font-size: 1.125rem;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 0.875rem;
}

.btn-spinner {
    width: 16px;
    height: 16px;
    border: 2px solid var(--white);
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

/* Loading Indicators */
.loading-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem 0;
    gap: 1rem;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

.loading-indicator-small {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem 0;
}

.spinner-small {
    width: 30px;
    height: 30px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* Empty States */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.empty-state h3 {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.empty-state p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.empty-state-small {
    text-align: center;
    padding: 2rem 1rem;
    color: var(--text-secondary);
}

/* Messages */
.error-message,
.success-message,
.warning-message {
    padding: 12px 16px;
    border-radius: 8px;
    margin-bottom: 1rem;
}

.error-message {
    background-color: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--danger-color);
    color: #fca5a5;
}

.success-message {
    background-color: rgba(16, 185, 129, 0.1);
    border: 1px solid var(--success-color);
    color: #6ee7b7;
}

.warning-message {
    background-color: rgba(245, 158, 11, 0.1);
    border: 1px solid var(--warning-color);
    color: #fcd34d;
}

/* Auth Pages */
.auth-container {
    min-height: calc(100vh - 200px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem 20px;
}

.auth-box {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2.5rem;
    max-width: 450px;
    width: 100%;
}

.auth-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    text-align: center;
    color: var(--text-primary);
}

.auth-subtitle {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.auth-form {
    margin-bottom: 1.5rem;
}

.auth-divider {
    text-align: center;
    margin: 1.5rem 0;
    position: relative;
}

.auth-divider::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    width: 100%;
    height: 1px;
    background-color: var(--border-color);
}

.auth-divider span {
    background-color: var(--card-bg);
    padding: 0 1rem;
    position: relative;
    color: var(--text-muted);
    font-size: 0.875rem;
}

.google-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
}

.auth-switch {
    text-align: center;
    color: var(--text-secondary);
    margin-top: 1.5rem;
}

/* Ask Question Page */
.ask-container {
    max-width: 800px;
    margin: 0 auto;
}

.page-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.page-subtitle {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.ask-form {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 2rem;
}

/* Profile Page */
.profile-header {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 2rem;
    display: flex;
    align-items: center;
    gap: 2rem;
    margin-bottom: 2rem;
}

.profile-avatar {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--white);
}

.profile-info {
    flex: 1;
}

.profile-name {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.profile-email {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.profile-role {
    display: inline-block;
    padding: 4px 12px;
    background-color: var(--primary-color);
    color: var(--white);
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

.profile-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 1.5rem;
    text-align: center;
}

.stat-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.25rem;
}

.stat-label {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.profile-tabs {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    border-bottom: 1px solid var(--border-color);
}

.tab-btn {
    padding: 1rem 1.5rem;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-weight: 600;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: all 0.3s ease;
}

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

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.profile-items {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

/* Footer */
.footer {
    background-color: var(--secondary-color);
    border-top: 1px solid var(--border-color);
    padding: 2rem 0;
    margin-top: auto;
    text-align: center;
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .hero-title {
        font-size: 1.875rem;
    }

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

    .search-bar {
        flex-direction: column;
    }

    .search-input {
        min-width: 100%;
    }

    .question-card {
        padding: 1rem;
    }

    .question-detail {
        padding: 1.5rem;
    }

    .question-detail-title {
        font-size: 1.5rem;
    }

    .profile-header {
        flex-direction: column;
        text-align: center;
    }

    .profile-name {
        font-size: 1.5rem;
    }

    .auth-box {
        padding: 1.5rem;
    }

    .form-actions {
        flex-direction: column;
    }

    .form-actions .btn {
        width: 100%;
    }

    .question-header {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero {
        padding: 2.5rem 0;
    }

    .profile-tabs {
        overflow-x: auto;
    }

    .tab-btn {
        white-space: nowrap;
    }
}