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

body {
    font-family: 'Inter', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #333;
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 600px;
}

.feedback-card {
    background: white;
    border-radius: 16px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.header {
    background: linear-gradient(90deg, #4f46e5 0%, #7c3aed 100%);
    color: white;
    padding: 30px;
    text-align: center;
}

.header h1 {
    font-weight: 700;
    font-size: 28px;
    margin-bottom: 8px;
}

.header p {
    opacity: 0.9;
    font-weight: 300;
}

.feedback-form {
    padding: 30px;
}

.form-group {
    margin-bottom: 24px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #374151;
}

input[type="text"],
input[type="email"],
textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-family: inherit;
    font-size: 16px;
    transition: border-color 0.2s;
}

input[type="text"]:focus,
input[type="email"]:focus,
textarea:focus {
    outline: none;
    border-color: #4f46e5;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

textarea {
    resize: vertical;
    min-height: 120px;
}

.file-upload {
    position: relative;
    margin-top: 8px;
}

input[type="file"] {
    position: absolute;
    left: -9999px;
}

.file-upload-label {
    display: inline-flex;
    align-items: center;
    padding: 12px 20px;
    background: #f3f4f6;
    border: 1px dashed #d1d5db;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.file-upload-label:hover {
    background: #e5e7eb;
    border-color: #9ca3af;
}

.file-upload-label i {
    margin-right: 8px;
    color: #4f46e5;
}

.file-name {
    margin-top: 8px;
    font-size: 14px;
    color: #6b7280;
}

small {
    color: #6b7280;
    font-size: 14px;
}

.submit-btn {
    width: 100%;
    padding: 14px 20px;
    background: linear-gradient(90deg, #4f46e5 0%, #7c3aed 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(79, 70, 229, 0.3);
}

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

.alert {
    padding: 16px;
    margin: 20px 30px;
    border-radius: 8px;
    display: flex;
    align-items: center;
}

.alert i {
    margin-right: 10px;
    font-size: 20px;
}

.alert.success {
    background: #ecfdf5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.alert.error {
    background: #fef2f2;
    color: #b91c1c;
    border: 1px solid #fecaca;
}

@media (max-width: 640px) {
    .header, .feedback-form {
        padding: 20px;
    }
    
    .header h1 {
        font-size: 24px;
    }
}