@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

:root {
    --bg-color: #0d1117;
    --card-bg: rgba(22, 27, 34, 0.7);
    --border-color: rgba(255, 255, 255, 0.1);
    --text-primary: #f0f6fc;
    --text-secondary: #8b949e;
    --accent: #58a6ff;
    --accent-hover: #3182ce;
    --accent-glow: rgba(88, 166, 255, 0.4);
    --danger: #f85149;
    --success: #238636;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    background-image: 
        radial-gradient(circle at 15% 50%, rgba(88, 166, 255, 0.15), transparent 25%),
        radial-gradient(circle at 85% 30%, rgba(163, 113, 247, 0.15), transparent 25%);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 500px;
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 24px;
    padding: 40px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
    animation: fadeUp 0.6s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes fadeUp {
    0% {
        opacity: 0;
        transform: translateY(20px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
    }
}

.header {
    text-align: center;
    margin-bottom: 30px;
}

.header h1 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 8px;
    background: linear-gradient(135deg, #58a6ff, #a371f7);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.header p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
}

.upload-area {
    position: relative;
    border: 2px dashed var(--border-color);
    border-radius: 16px;
    padding: 40px 20px;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    background: rgba(255, 255, 255, 0.02);
    margin-bottom: 24px;
}

.upload-area:hover, .upload-area.dragover {
    border-color: var(--accent);
    background: rgba(88, 166, 255, 0.05);
    box-shadow: 0 0 20px var(--accent-glow);
}

.upload-icon {
    font-size: 48px;
    color: var(--accent);
    margin-bottom: 16px;
    transition: transform 0.3s ease;
}

.upload-area:hover .upload-icon {
    transform: translateY(-5px);
}

.upload-text {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: 8px;
}

.upload-hint {
    font-size: 12px;
    color: var(--text-secondary);
}

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

.file-name {
    margin-top: 12px;
    font-size: 14px;
    color: var(--accent);
    font-weight: 500;
    word-break: break-all;
}

.btn-submit {
    width: 100%;
    padding: 14px;
    border: none;
    border-radius: 12px;
    background: linear-gradient(to right, #58a6ff, #a371f7);
    color: white;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(88, 166, 255, 0.3);
}

.btn-submit:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(88, 166, 255, 0.5);
}

.btn-submit:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    background: var(--text-secondary);
    box-shadow: none;
}

.flash-messages {
    margin-bottom: 20px;
}

.flash {
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 14px;
    margin-bottom: 10px;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.flash.error {
    background-color: rgba(248, 81, 73, 0.1);
    border: 1px solid var(--danger);
    color: #ff7b72;
}

.flash.success {
    background-color: rgba(35, 134, 54, 0.1);
    border: 1px solid var(--success);
    color: #3fb950;
}

.loader {
    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 ease-in-out infinite;
    margin: 0 auto;
}

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

.btn-submit.loading .btn-text {
    display: none;
}

.btn-submit.loading .loader {
    display: block;
}