:root {
    --primary-color: #ff3e3e; /* 山科SONICの情熱をイメージした赤 */
    --secondary-color: #2d3436;
    --accent-color: #fab1a0;
    --background-gradient: linear-gradient(135deg, #0f0c29, #302b63, #24243e);
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-color: #ffffff;
    --text-muted: #b2bec3;
    --input-bg: rgba(0, 0, 0, 0.2);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Inter', 'Noto Sans JP', sans-serif;
    background: var(--background-gradient);
    background-attachment: fixed;
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 600px;
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
    animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

h1 {
    font-size: 2rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: 10px;
    background: linear-gradient(to right, #fff, var(--primary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 30px;
}

.form-group {
    margin-bottom: 20px;
    position: relative;
}

label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--accent-color);
}

.label-hint {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: normal;
    margin-left: 5px;
}

input[type="text"],
input[type="email"],
input[type="tel"],
textarea {
    width: 100%;
    padding: 12px 16px;
    background: #ffffff;
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    color: #333333;
    font-size: 1rem;
    transition: var(--transition);
    outline: none;
}

input:focus,
textarea:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(255, 62, 62, 0.2);
    background: #ffffff;
}

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

.char-count {
    font-size: 0.75rem;
    text-align: right;
    color: var(--text-muted);
    margin-top: 5px;
}

.file-input-wrapper {
    position: relative;
    overflow: hidden;
    display: inline-block;
    width: 100%;
}

.file-input-label {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background: var(--input-bg);
    border: 2px dashed var(--glass-border);
    border-radius: 10px;
    padding: 30px;
    cursor: pointer;
    transition: var(--transition);
}

.file-input-label:hover {
    border-color: var(--primary-color);
    background: rgba(255, 62, 62, 0.05);
}

input[type="file"] {
    position: absolute;
    left: 0;
    top: 0;
    opacity: 0;
    cursor: pointer;
    width: 100%;
    height: 100%;
}

.preview-container {
    margin-top: 15px;
    display: none;
}

.preview-image {
    width: 100%;
    max-height: 200px;
    object-fit: cover;
    border-radius: 10px;
    border: 1px solid var(--glass-border);
}

.submit-btn {
    width: 100%;
    padding: 15px;
    background: var(--primary-color);
    border: none;
    border-radius: 12px;
    color: white;
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    margin-top: 20px;
    box-shadow: 0 4px 15px rgba(255, 62, 62, 0.3);
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 62, 62, 0.4);
    filter: brightness(1.1);
}

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

.submit-btn:disabled {
    background: var(--text-muted);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.loading-spinner {
    display: none;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

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

/* Response Message */
#message-display {
    margin-top: 20px;
    padding: 15px;
    border-radius: 10px;
    text-align: center;
    display: none;
}

.success {
    background: rgba(46, 204, 113, 0.2);
    border: 1px solid #2ecc71;
    color: #2ecc71;
}

.error {
    background: rgba(231, 76, 60, 0.2);
    border: 1px solid #e74c3c;
    color: #e74c3c;
}

@media (max-width: 480px) {
    .container {
        padding: 20px;
    }
    
    h1 {
        font-size: 1.5rem;
    }
}