:root {
    --bg-color: #0b0f19;
    --card-bg: rgba(20, 26, 40, 0.7);
    --border-color: rgba(255, 255, 255, 0.1);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --error-bg: rgba(239, 68, 68, 0.1);
    --error-text: #ef4444;
}

* {
    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(59, 130, 246, 0.15), transparent 25%),
        radial-gradient(circle at 85% 30%, rgba(139, 92, 246, 0.15), transparent 25%);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.login-container {
    width: 100%;
    max-width: 400px;
    padding: 20px;
    animation: fadeIn 0.8s ease-out;
}

.login-card {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.login-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 30px 60px -15px rgba(0, 0, 0, 0.6);
}

.brand {
    text-align: center;
    margin-bottom: 40px;
}

.logo-icon {
    width: 48px;
    height: 48px;
    margin: 0 auto 16px;
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    border-radius: 12px;
    position: relative;
    box-shadow: 0 0 20px rgba(59, 130, 246, 0.4);
}

.logo-icon::after {
    content: '';
    position: absolute;
    inset: 2px;
    background: var(--card-bg);
    border-radius: 10px;
    z-index: 1;
}

.logo-icon::before {
    content: '';
    position: absolute;
    inset: 12px;
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    border-radius: 4px;
    z-index: 2;
    animation: pulse 2s infinite ease-in-out;
}

h1 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 8px;
    letter-spacing: -0.5px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 14px;
}

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

label {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
}

input {
    width: 100%;
    padding: 12px 16px;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    color: var(--text-primary);
    font-size: 15px;
    font-family: inherit;
    transition: all 0.2s ease;
}

input:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
    background: rgba(0, 0, 0, 0.3);
}

input::placeholder {
    color: rgba(148, 163, 184, 0.5);
}

.submit-btn {
    width: 100%;
    padding: 14px;
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.submit-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

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

.btn-loader {
    display: none;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
}

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

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

.error-message {
    display: none;
    background: var(--error-bg);
    color: var(--error-text);
    padding: 12px;
    border-radius: 8px;
    font-size: 14px;
    margin-bottom: 20px;
    text-align: center;
    border: 1px solid rgba(239, 68, 68, 0.2);
    animation: slideDown 0.3s ease-out;
}

.shake {
    animation: shake 0.5s cubic-bezier(.36,.07,.19,.97) both;
}

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

@keyframes pulse {
    0% { transform: scale(1); opacity: 0.8; }
    50% { transform: scale(1.1); opacity: 1; }
    100% { transform: scale(1); opacity: 0.8; }
}

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

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes shake {
    10%, 90% { transform: translate3d(-1px, 0, 0); }
    20%, 80% { transform: translate3d(2px, 0, 0); }
    30%, 50%, 70% { transform: translate3d(-4px, 0, 0); }
    40%, 60% { transform: translate3d(4px, 0, 0); }
}