* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    text-align: center;
    padding: 40px 20px;
    color: white;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 15px;
}

.logo-icon {
    font-size: 48px;
}

.logo h1 {
    font-size: 48px;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.tagline {
    font-size: 18px;
    opacity: 0.9;
}

.main-content {
    flex: 1;
    padding: 20px 0;
}

.feature-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    margin-bottom: 30px;
}

.feature-card {
    background: white;
    border-radius: 16px;
    padding: 35px 30px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

.feature-icon {
    font-size: 56px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 24px;
    color: #333;
    margin-bottom: 12px;
}

.feature-card p {
    color: #666;
    font-size: 15px;
    line-height: 1.6;
}

.tool-section {
    background: white;
    border-radius: 16px;
    padding: 35px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid #f0f0f0;
}

.section-header h2 {
    font-size: 26px;
    color: #333;
}

.back-btn {
    background: #f5f5f5;
    color: #666;
    border: none;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.2s;
}

.back-btn:hover {
    background: #e0e0e0;
}

.input-group {
    margin-bottom: 25px;
}

.input-group label {
    display: block;
    font-size: 15px;
    font-weight: 600;
    color: #333;
    margin-bottom: 10px;
}

.input-group input[type="text"],
.input-group textarea {
    width: 100%;
    padding: 14px 18px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 15px;
    transition: border-color 0.2s;
    font-family: inherit;
}

.input-group input[type="text"]:focus,
.input-group textarea:focus {
    outline: none;
    border-color: #667eea;
}

.input-group textarea {
    resize: vertical;
    min-height: 150px;
}

.difficulty-options {
    display: flex;
    gap: 20px;
}

.radio-label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    font-size: 15px;
}

.radio-label input[type="radio"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.submit-btn {
    width: 100%;
    padding: 16px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 17px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

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

.result-box {
    margin-top: 30px;
    padding: 25px;
    background: #f8f9ff;
    border-radius: 12px;
    border-left: 4px solid #667eea;
}

.result-box h3 {
    font-size: 18px;
    color: #333;
    margin-bottom: 15px;
}

.suggestions-content {
    font-size: 15px;
    line-height: 1.8;
    color: #444;
}

.suggestions-content h4 {
    color: #667eea;
    margin: 15px 0 8px;
}

.interview-setup {
    max-width: 600px;
    margin: 0 auto;
}

.interview-active {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 300px);
    min-height: 500px;
}

.interview-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    background: #f5f5f5;
    border-radius: 10px;
    margin-bottom: 20px;
}

#current-position {
    font-weight: 600;
    color: #333;
}

.phase-badge {
    background: #667eea;
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 13px;
}

.interview-messages {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    background: #fafafa;
    border-radius: 12px;
    margin-bottom: 20px;
    max-height: 400px;
}

.message {
    margin-bottom: 20px;
    padding: 15px 20px;
    border-radius: 12px;
    max-width: 85%;
    line-height: 1.6;
    font-size: 15px;
}

.message.interviewer {
    background: #667eea;
    color: white;
    margin-right: auto;
}

.message.candidate {
    background: #e8f5e9;
    color: #333;
    margin-left: auto;
}

.message.feedback {
    background: #fff3e0;
    color: #333;
    border-left: 4px solid #ff9800;
    margin: 20px 0;
}

.interview-input-area {
    margin-bottom: 15px;
}

.interview-input-area textarea {
    width: 100%;
    padding: 14px 18px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 15px;
    resize: none;
    font-family: inherit;
}

.interview-input-area textarea:focus {
    outline: none;
    border-color: #667eea;
}

.input-actions {
    display: flex;
    gap: 15px;
    margin-top: 12px;
}

.action-btn {
    flex: 1;
    padding: 14px;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.action-btn.primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.action-btn.secondary {
    background: #f5f5f5;
    color: #666;
}

.action-btn:hover {
    transform: translateY(-2px);
}

.interview-controls {
    text-align: center;
}

.control-btn {
    background: #ff6b6b;
    color: white;
    border: none;
    padding: 12px 30px;
    border-radius: 8px;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
}

.control-btn:hover {
    background: #ee5a5a;
}

.interview-feedback {
    padding: 25px;
    background: #f8f9ff;
    border-radius: 12px;
}

.interview-feedback h3 {
    font-size: 22px;
    color: #333;
    margin-bottom: 20px;
}

.feedback-content {
    font-size: 15px;
    line-height: 1.8;
    color: #444;
    margin-bottom: 25px;
}

.chat-container {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 350px);
    min-height: 400px;
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    background: #fafafa;
    border-radius: 12px;
    margin-bottom: 20px;
}

.chat-message {
    margin-bottom: 15px;
    padding: 12px 18px;
    border-radius: 12px;
    max-width: 85%;
    line-height: 1.6;
    font-size: 15px;
}

.chat-message.assistant {
    background: #e3f2fd;
    color: #333;
    margin-right: auto;
}

.chat-message.user {
    background: #f3e5f5;
    color: #333;
    margin-left: auto;
}

.chat-input-area {
    display: flex;
    gap: 15px;
}

.chat-input-area input {
    flex: 1;
    padding: 14px 18px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 15px;
}

.chat-input-area input:focus {
    outline: none;
    border-color: #667eea;
}

.send-btn {
    padding: 14px 28px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.send-btn:hover {
    transform: translateY(-2px);
}

.footer {
    text-align: center;
    padding: 25px;
    color: rgba(255,255,255,0.8);
    font-size: 14px;
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

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

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

.loading-overlay p {
    color: white;
    margin-top: 15px;
    font-size: 15px;
}

@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .header {
        padding: 30px 15px;
    }
    
    .logo h1 {
        font-size: 36px;
    }
    
    .feature-section {
        grid-template-columns: 1fr;
    }
    
    .tool-section {
        padding: 25px 20px;
    }
    
    .difficulty-options {
        flex-direction: column;
        gap: 12px;
    }
    
    .message {
        max-width: 95%;
    }
    
    .input-actions {
        flex-direction: column;
    }
}